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Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
General Relativity as an Effective Field Theory
Sven Faller
Theoretical Physics 1
University of Siegen
Theory Seminar 18.12.2006
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
table of contents
1
Introduction
2
Quantum Gravity
3
Effective Field Theory of Gravity
4
Leading Quantum Corrections
5
Evaluation of the Vertex Corrections
6
Gravitational Potential
7
Potential Definitions
8
Summary
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation
all known field theories: quantum field theories
gravity quantization - Feynman´s Gedankenexperiment
gravity must be a quantum field theory
problem: consistent quantization method unknown
Quantum Gravity: De Witt, Feynman, ’t Hooft and Veltman
present energies, quantum gravity non-renormalizable
low-energy predictions independent of high-energy
influence
Donoghue:
possible solution Effective Field Theory of Gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation of Quantization
Feynman´s Gedankenexperiment: two-slit diffraction
experiment with gravity detector
characteristic for a quantum field ⇒ should be described
by an amplitude rather than a probability
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Motivation of Quantization
Feynman´s Gedankenexperiment: two-slit diffraction
experiment with gravity detector
characteristic for a quantum field ⇒ should be described
by an amplitude rather than a probability
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Laws (1687)
law of inertia
no external force : ddt~r = ~v = const.
⇒ inertial frame of reference (IS)
second law
force ∝ inertia mass mi
⇒
~ = mi · ~a.
F
third law
actio est reactio
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Laws (1687)
law of inertia
no external force : ddt~r = ~v = const.
⇒ inertial frame of reference (IS)
second law
force ∝ inertia mass mi
⇒
~ = mi · ~a.
F
third law
actio est reactio
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Laws (1687)
law of inertia
no external force : ddt~r = ~v = const.
⇒ inertial frame of reference (IS)
second law
force ∝ inertia mass mi
⇒
~ = mi · ~a.
F
third law
actio est reactio
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Relativity
three different masses: inertia mass mi , passive
gravitational mass mG and active gravitational mass MG
third law: passive and active gravitational mass equal
force of gravity
~ 12 (~r ) = −G m1 m2 ~r1 − ~r2
F
|~r1 − ~r2 |3
problem: equality of inertia and passive masses
experimental measurements: verification of equality,
bases for Einstein’s Principle of Equivalence
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Relativity
three different masses: inertia mass mi , passive
gravitational mass mG and active gravitational mass MG
third law: passive and active gravitational mass equal
force of gravity
~ 12 (~r ) = −G m1 m2 ~r1 − ~r2
F
|~r1 − ~r2 |3
problem: equality of inertia and passive masses
experimental measurements: verification of equality,
bases for Einstein’s Principle of Equivalence
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Relativity
three different masses: inertia mass mi , passive
gravitational mass mG and active gravitational mass MG
third law: passive and active gravitational mass equal
force of gravity
~ 12 (~r ) = −G m1 m2 ~r1 − ~r2
F
|~r1 − ~r2 |3
problem: equality of inertia and passive masses
experimental measurements: verification of equality,
bases for Einstein’s Principle of Equivalence
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Relativity
three different masses: inertia mass mi , passive
gravitational mass mG and active gravitational mass MG
third law: passive and active gravitational mass equal
force of gravity
~ 12 (~r ) = −G m1 m2 ~r1 − ~r2
F
|~r1 − ~r2 |3
problem: equality of inertia and passive masses
experimental measurements: verification of equality,
bases for Einstein’s Principle of Equivalence
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Newton’s Relativity
three different masses: inertia mass mi , passive
gravitational mass mG and active gravitational mass MG
third law: passive and active gravitational mass equal
force of gravity
~ 12 (~r ) = −G m1 m2 ~r1 − ~r2
F
|~r1 − ~r2 |3
problem: equality of inertia and passive masses
experimental measurements: verification of equality,
bases for Einstein’s Principle of Equivalence
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Einstein’s Special Relativity
Newton: Galilei transformations between IS
Einstein 1905: Newton’s Theory must be specialized by
universality of the velocity of light in all frames
x 7−→ x 0 = Λ x + a
(Lorentz transformation)
Postulate
general transformation for the line element must satisfy
ds2 = ηαβ dx µ dx ν = c2 dt 2 − d ~x 2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Einstein’s Special Relativity
Newton: Galilei transformations between IS
Einstein 1905: Newton’s Theory must be specialized by
universality of the velocity of light in all frames
x 7−→ x 0 = Λ x + a
(Lorentz transformation)
Postulate
general transformation for the line element must satisfy
ds2 = ηαβ dx µ dx ν = c2 dt 2 − d ~x 2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Einstein’s Special Relativity
Newton: Galilei transformations between IS
Einstein 1905: Newton’s Theory must be specialized by
universality of the velocity of light in all frames
x 7−→ x 0 = Λ x + a
(Lorentz transformation)
Postulate
general transformation for the line element must satisfy
ds2 = ηαβ dx µ dx ν = c2 dt 2 − d ~x 2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
General Relativity
Einstein (1916):
Die Grundlagen der allgemeinen Relativitätstheorie. Ann. d. Physik,
322(10):891-921
Newton: space R3 and parameter time Rt
Einstein : new relations between space-time and mass
⇒ curved space-time mannifold
curvature of space = measure for mass:
„matter tells space how to curve, and space tells matter
how to move“ (Miesner, 1973)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
General Relativity
Einstein (1916):
Die Grundlagen der allgemeinen Relativitätstheorie. Ann. d. Physik,
322(10):891-921
Newton: space R3 and parameter time Rt
Einstein : new relations between space-time and mass
⇒ curved space-time mannifold
curvature of space = measure for mass:
„matter tells space how to curve, and space tells matter
how to move“ (Miesner, 1973)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
General Relativity
Einstein (1916):
Die Grundlagen der allgemeinen Relativitätstheorie. Ann. d. Physik,
322(10):891-921
Newton: space R3 and parameter time Rt
Einstein : new relations between space-time and mass
⇒ curved space-time mannifold
curvature of space = measure for mass:
„matter tells space how to curve, and space tells matter
how to move“ (Miesner, 1973)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
General Relativity
Einstein (1916):
Die Grundlagen der allgemeinen Relativitätstheorie. Ann. d. Physik,
322(10):891-921
Newton: space R3 and parameter time Rt
Einstein : new relations between space-time and mass
⇒ curved space-time mannifold
curvature of space = measure for mass:
„matter tells space how to curve, and space tells matter
how to move“ (Miesner, 1973)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
General Relativity
Einstein (1916):
Die Grundlagen der allgemeinen Relativitätstheorie. Ann. d. Physik,
322(10):891-921
Newton: space R3 and parameter time Rt
Einstein : new relations between space-time and mass
⇒ curved space-time mannifold
curvature of space = measure for mass:
„matter tells space how to curve, and space tells matter
how to move“ (Miesner, 1973)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of Equivalence
„At every space-time point in an arbitrary gravitational field it is possible to
choose a „locally inertial coordinate system“ such that, within sufficiently
small region of the point in question, the laws of nature take the same form as
in unaccelerated Cartesian coordinate systems in absence of gravitation.“
relation between accelerated local IS x α and static frame
of reference x̄ µ described by metric tensor, which leaves
line element ds2 invariant:
gµν = ηαβ
Sven Faller
∂x α ∂x β
∂ x̄ µ ∂ x̄ ν
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of Equivalence
„At every space-time point in an arbitrary gravitational field it is possible to
choose a „locally inertial coordinate system“ such that, within sufficiently
small region of the point in question, the laws of nature take the same form as
in unaccelerated Cartesian coordinate systems in absence of gravitation.“
relation between accelerated local IS x α and static frame
of reference x̄ µ described by metric tensor, which leaves
line element ds2 invariant:
gµν = ηαβ
Sven Faller
∂x α ∂x β
∂ x̄ µ ∂ x̄ ν
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of Equivalence
„At every space-time point in an arbitrary gravitational field it is possible to
choose a „locally inertial coordinate system“ such that, within sufficiently
small region of the point in question, the laws of nature take the same form as
in unaccelerated Cartesian coordinate systems in absence of gravitation.“
relation between accelerated local IS x α and static frame
of reference x̄ µ described by metric tensor, which leaves
line element ds2 invariant:
gµν = ηαβ
Sven Faller
∂x α ∂x β
∂ x̄ µ ∂ x̄ ν
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of General Covariance
General laws of nature should be expressed in terms of
equations which are true in all frames of reference and
transform covariantly by arbitrary substitutions.
general coordinate transformation: x 7−→ x 0 = f (x)
Principle of General Covariance is not an invariance
principle like Principle of Galilean or Special Relativity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of General Covariance
General laws of nature should be expressed in terms of
equations which are true in all frames of reference and
transform covariantly by arbitrary substitutions.
general coordinate transformation: x 7−→ x 0 = f (x)
Principle of General Covariance is not an invariance
principle like Principle of Galilean or Special Relativity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Principle of General Covariance
General laws of nature should be expressed in terms of
equations which are true in all frames of reference and
transform covariantly by arbitrary substitutions.
general coordinate transformation: x 7−→ x 0 = f (x)
Principle of General Covariance is not an invariance
principle like Principle of Galilean or Special Relativity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Recall: Lorentz Invariance
global coordinate change: x µ 7−→ x 0µ = Λµν x ν
Minkowski metric ηµν invariant
fields transform as scalars, vectors, etc.
φ(x) 7−→ φ0 (x 0 ) = φ(x)
Aµ (x) 7−→ A0µ (x) = Λµν (x) Aν (x)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Recall: Lorentz Invariance
global coordinate change: x µ 7−→ x 0µ = Λµν x ν
Minkowski metric ηµν invariant
fields transform as scalars, vectors, etc.
φ(x) 7−→ φ0 (x 0 ) = φ(x)
Aµ (x) 7−→ A0µ (x) = Λµν (x) Aν (x)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Recall: Lorentz Invariance
global coordinate change: x µ 7−→ x 0µ = Λµν x ν
Minkowski metric ηµν invariant
fields transform as scalars, vectors, etc.
φ(x) 7−→ φ0 (x 0 ) = φ(x)
Aµ (x) 7−→ A0µ (x) = Λµν (x) Aν (x)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Covariant Derivative
local coordinate changes require covariant derivative:
Dµ Aν = ∂µ Aν + Γνµλ Aλ = Aν ,µ + Γνµλ Aλ ≡ Aν ;µ
affine connection Γλµν (geometric interpretation)
for scalar fields: Φ;µ ≡ Φ,µ = ∂µ Φ
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Covariant Derivative
local coordinate changes require covariant derivative:
Dµ Aν = ∂µ Aν + Γνµλ Aλ = Aν ,µ + Γνµλ Aλ ≡ Aν ;µ
affine connection Γλµν (geometric interpretation)
for scalar fields: Φ;µ ≡ Φ,µ = ∂µ Φ
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Covariant Derivative
local coordinate changes require covariant derivative:
Dµ Aν = ∂µ Aν + Γνµλ Aλ = Aν ,µ + Γνµλ Aλ ≡ Aν ;µ
affine connection Γλµν (geometric interpretation)
for scalar fields: Φ;µ ≡ Φ,µ = ∂µ Φ
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Fundamentals
General Relativity
Riemann Space (R4 )
metric definition: ds2 = gµν (x) dx µ dx ν
affine connection: Γλµν = 12 g λσ ∂µ gνσ + ∂ν gνσ − ∂σ gµν
λ
Ricci identity: Aµ;σν − Aµ;νσ ≡ Aλ Rµσν
Riemann curvature tensor:
R λµσν = Γλµν,σ − Γλµσ,ν + Γλτσ Γτµν − Γλτν Γτµσ
Ricci tensor: Rµν = R λµλν ≡ Rνµ
Ricci scalar: R = g µν Rµν
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
General relativity as a gauge theory (Sabbata 1985)
Poincaré group is non abelian
cf. Yang-Mills theory
1
1 a a µν
F
= − trF 2
Lgauge = − Fµν
4
2
gravity: introduction of vierbein- or tetrad fields eµλ̄
Lgauge = −
e µ ν
2 √
ω ) ≡ 2 −g R
e e R λ̄σ̄ (ω
2g λ̄ σ̄ µν
κ
with g = det[gµν ] and κ2 = 32πG.
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
General relativity as a gauge theory (Sabbata 1985)
Poincaré group is non abelian
cf. Yang-Mills theory
1
1 a a µν
F
= − trF 2
Lgauge = − Fµν
4
2
gravity: introduction of vierbein- or tetrad fields eµλ̄
Lgauge = −
e µ ν
2 √
ω ) ≡ 2 −g R
e e R λ̄σ̄ (ω
2g λ̄ σ̄ µν
κ
with g = det[gµν ] and κ2 = 32πG.
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
General relativity as a gauge theory (Sabbata 1985)
Poincaré group is non abelian
cf. Yang-Mills theory
1
1 a a µν
F
= − trF 2
Lgauge = − Fµν
4
2
gravity: introduction of vierbein- or tetrad fields eµλ̄
Lgauge = −
e µ ν
2 √
ω ) ≡ 2 −g R
e e R λ̄σ̄ (ω
2g λ̄ σ̄ µν
κ
with g = det[gµν ] and κ2 = 32πG.
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Background Field Method
introduced by ’t Hooft and Veltmann (1974)
gravitational field expanded about smooth background
metric ḡµν
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
classical equations of motion: ḡµν
quantum field hµν : all dynamical information
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Background Field Method
introduced by ’t Hooft and Veltmann (1974)
gravitational field expanded about smooth background
metric ḡµν
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
classical equations of motion: ḡµν
quantum field hµν : all dynamical information
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Background Field Method
introduced by ’t Hooft and Veltmann (1974)
gravitational field expanded about smooth background
metric ḡµν
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
classical equations of motion: ḡµν
quantum field hµν : all dynamical information
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Background Field Method
introduced by ’t Hooft and Veltmann (1974)
gravitational field expanded about smooth background
metric ḡµν
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
classical equations of motion: ḡµν
quantum field hµν : all dynamical information
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Gravitational Action
Einstein-Hilbert action Svac =
R
matter action Sm = d 4 x Lm
Sgr = Svac + Sm =
Z
R
4
d 4x
d x
√
√
−g
2
κ2
R
2
−g 2 R + Lm
κ
further gauge invariant terms
√
2
2
µν
L = −g λ + 2 R + c1 R + c2 Rµν R + . . . + Lm
κ
upper bound: constants c1 , c2 < 1074 (Stelle 1978)
λ ≡ −8πGΛ, cosmological constant Λ ≡ 0
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Expansion: Vacuum Lagrangian
metric expansion:

ff
p
p
κ α
κ2 α β
κ2 ` α ´2
−g = −ḡ 1 − hα
−
hβ hα +
hα + O(h3 )
2
4
8
Lagrangian expansion
»
–
p
2 p
2
(1)
(2)
−gR = −ḡ 2 R̄ + Lgr + Lgr + . . . ,
2
κ
κ
ˆ µν
˜
1
(1)
Lgr = hµν ḡ R̄ − 2R̄ µν ,
κ
1
1
(2)
Lgr = Dα hµν Dα hµν − Dα h Dα h + Dα h Dβ hαβ − Dα hµβ Dβ hµα
2
2
„
«
´
` λ
1 2
1
hνλ − h hµν .
+ R̄
h − hµν hµν + R̄ µν 2hµ
4
2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Expansion: Vacuum Lagrangian
metric expansion:

ff
p
p
κ α
κ2 α β
κ2 ` α ´2
−g = −ḡ 1 − hα
−
hβ hα +
hα + O(h3 )
2
4
8
Lagrangian expansion
»
–
p
2 p
2
(1)
(2)
−gR = −ḡ 2 R̄ + Lgr + Lgr + . . . ,
2
κ
κ
ˆ µν
˜
1
(1)
Lgr = hµν ḡ R̄ − 2R̄ µν ,
κ
1
1
(2)
Lgr = Dα hµν Dα hµν − Dα h Dα h + Dα h Dβ hαβ − Dα hµβ Dβ hµα
2
2
„
«
´
` λ
1 2
1
hνλ − h hµν .
+ R̄
h − hµν hµν + R̄ µν 2hµ
4
2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Expansion: Matter Lagrangian
e.g. scalar particle: Lm =
Lagrangian expansion:
√
−g
1
2g
µν ∂ φ∂ φ
µ
ν
− 12 m2 φ2
p
¯
˘ (0)
(1)
(2)
−ḡ Lm + Lm + Lm + . . .
´
1`
=
∂µ φ∂ µ φ − m2 φ2
2
κ
= − hµν T µν
2
`
´
1
≡ ∂µ φ∂ µ φ − ḡµν ∂λ φ∂ λ φ − m2 φ2
(energy-momentum-tensor)
2
„
«
„
«
2
ˆ
˜
1 µλ ν
1
κ
1
= κ2
h hλ − hhµν ∂µ φ∂ν φ −
hλσ hλσ − hh ∂µ φ ∂ µ φ − m2 φ2
2
4
8
2
Lm =
(0)
Lm
(1)
Lm
T µν
(2)
Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Expansion: Matter Lagrangian
e.g. scalar particle: Lm =
Lagrangian expansion:
√
−g
1
2g
µν ∂ φ∂ φ
µ
ν
− 12 m2 φ2
p
¯
˘ (0)
(1)
(2)
−ḡ Lm + Lm + Lm + . . .
´
1`
=
∂µ φ∂ µ φ − m2 φ2
2
κ
= − hµν T µν
2
`
´
1
≡ ∂µ φ∂ µ φ − ḡµν ∂λ φ∂ λ φ − m2 φ2
(energy-momentum-tensor)
2
„
«
„
«
2
ˆ
˜
1 µλ ν
1
κ
1
= κ2
h hλ − hhµν ∂µ φ∂ν φ −
hλσ hλσ − hh ∂µ φ ∂ µ φ − m2 φ2
2
4
8
2
Lm =
(0)
Lm
(1)
Lm
T µν
(2)
Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Einstein Equation
Rµν −
1
κ2
gµν R =
Tµν
2
4
ḡµν satisfies Einstein equation
Lagrangian terms linear in quantum field hµν vanish
one-loop order:

2 R̄
(0)
+ Lm
κ2
ff
L0 =
p
−ḡ
Lquad =
p
˘ (2)
(2) ¯
−ḡ Lg + Lgf + Lghost + Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Einstein Equation
Rµν −
1
κ2
gµν R =
Tµν
2
4
ḡµν satisfies Einstein equation
Lagrangian terms linear in quantum field hµν vanish
one-loop order:

2 R̄
(0)
+ Lm
κ2
ff
L0 =
p
−ḡ
Lquad =
p
˘ (2)
(2) ¯
−ḡ Lg + Lgf + Lghost + Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Einstein Equation
Rµν −
1
κ2
gµν R =
Tµν
2
4
ḡµν satisfies Einstein equation
Lagrangian terms linear in quantum field hµν vanish
one-loop order:

2 R̄
(0)
+ Lm
κ2
ff
L0 =
p
−ḡ
Lquad =
p
˘ (2)
(2) ¯
−ḡ Lg + Lgf + Lghost + Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Einstein Equation
Rµν −
1
κ2
gµν R =
Tµν
2
4
ḡµν satisfies Einstein equation
Lagrangian terms linear in quantum field hµν vanish
one-loop order:

2 R̄
(0)
+ Lm
κ2
ff
L0 =
p
−ḡ
Lquad =
p
˘ (2)
(2) ¯
−ḡ Lg + Lgf + Lghost + Lm
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Quantization Problems
field equations non linear
coupling constant κ has mass dimension
coupling grows with energy
possible solution: Effective Field Theory
separate high enery fluctuations from small quantum
fluctuations at ordinary energies
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Quantization Problems
field equations non linear
coupling constant κ has mass dimension
coupling grows with energy
possible solution: Effective Field Theory
separate high enery fluctuations from small quantum
fluctuations at ordinary energies
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Quantization Problems
field equations non linear
coupling constant κ has mass dimension
coupling grows with energy
possible solution: Effective Field Theory
separate high enery fluctuations from small quantum
fluctuations at ordinary energies
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Quantization
Quantization Problems
field equations non linear
coupling constant κ has mass dimension
coupling grows with energy
possible solution: Effective Field Theory
separate high enery fluctuations from small quantum
fluctuations at ordinary energies
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Introduction
Effective Lagrangian
low-energy d.o.f.: hµν + ghost fields + matter fields
Z
Z[J] =
[dφ][dhµν ]eiSeff (φ,ḡ,h,J)
p
R
Seff = d 4 x −ḡ Leff , Leff = Lgr + Lm
effective Lagrangian = expansion in powers of hµν
(0)
(2)
(0)
(2)
(4)
Lgr = Lgr + Lgr + Lgr + . . .
Lm = Lm + Lm + . . .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Introduction
Effective Lagrangian
low-energy d.o.f.: hµν + ghost fields + matter fields
Z
Z[J] =
[dφ][dhµν ]eiSeff (φ,ḡ,h,J)
p
R
Seff = d 4 x −ḡ Leff , Leff = Lgr + Lm
effective Lagrangian = expansion in powers of hµν
(0)
(2)
(0)
(2)
(4)
Lgr = Lgr + Lgr + Lgr + . . .
Lm = Lm + Lm + . . .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Introduction
Effective Lagrangian
low-energy d.o.f.: hµν + ghost fields + matter fields
Z
Z[J] =
[dφ][dhµν ]eiSeff (φ,ḡ,h,J)
p
R
Seff = d 4 x −ḡ Leff , Leff = Lgr + Lm
effective Lagrangian = expansion in powers of hµν
(0)
(2)
(0)
(2)
(4)
Lgr = Lgr + Lgr + Lgr + . . .
Lm = Lm + Lm + . . .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Graviton Progpagator
second order Lagrangian Lgr
harmonic gauge → gauge fixing Lagrangian Lgf
γδ
1 αβ
quantum field hµν bilinear Lagrangian Lfree
∆−1
gr = − 2 h
αβγδ h
graviton propagator in harmonic gauge
αβ
q
µν
=
1
i
η αµ η βν + η αν η βµ − η αβ η µν
2
2 q + i
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Graviton Progpagator
second order Lagrangian Lgr
harmonic gauge → gauge fixing Lagrangian Lgf
γδ
1 αβ
quantum field hµν bilinear Lagrangian Lfree
∆−1
gr = − 2 h
αβγδ h
graviton propagator in harmonic gauge
αβ
q
µν
=
1
i
η αµ η βν + η αν η βµ − η αβ η µν
2
2 q + i
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Graviton Progpagator
second order Lagrangian Lgr
harmonic gauge → gauge fixing Lagrangian Lgf
γδ
1 αβ
quantum field hµν bilinear Lagrangian Lfree
∆−1
gr = − 2 h
αβγδ h
graviton propagator in harmonic gauge
αβ
q
µν
=
1
i
η αµ η βν + η αν η βµ − η αβ η µν
2
2 q + i
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Graviton Progpagator
second order Lagrangian Lgr
harmonic gauge → gauge fixing Lagrangian Lgf
γδ
1 αβ
quantum field hµν bilinear Lagrangian Lfree
∆−1
gr = − 2 h
αβγδ h
graviton propagator in harmonic gauge
αβ
q
µν
=
1
i
η αµ η βν + η αν η βµ − η αβ η µν
2
2 q + i
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Vertex Factors
vertex factors at one-loop order
q
−→
p0
`-
p0
p
`0 %
p
Sven Faller
k
−→
%`
&q
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Scalar-Graviton-Vertex
vertexZfactor
τµν = i
0
∂
∂
∂
d 4 x d 4 x1 d 4 x2 d 4 x3 ei(px1 −p x2 +qx3 ) ·
∂φ(x1 ) ∂φ(x2 ) ∂hµν (x3 )

»
–ff
`
κ αβ
1
γ
2
2´
· − h · ∂α φ(x)∂β φ(x) − ηαβ ∂γ φ(x)∂ φ(x) − m φ(x)
2
scalar-graviton-vertex
q
p0
iκ
0
0
0
2
µν = −
pµ pν + pν pµ − ηµν p · p − m
2
−→
p
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Scalar-Graviton-Vertex
vertexZfactor
τµν = i
0
∂
∂
∂
d 4 x d 4 x1 d 4 x2 d 4 x3 ei(px1 −p x2 +qx3 ) ·
∂φ(x1 ) ∂φ(x2 ) ∂hµν (x3 )

»
–ff
`
κ αβ
1
γ
2
2´
· − h · ∂α φ(x)∂β φ(x) − ηαβ ∂γ φ(x)∂ φ(x) − m φ(x)
2
scalar-graviton-vertex
q
p0
iκ
0
0
0
2
µν = −
pµ pν + pν pµ − ηµν p · p − m
2
−→
p
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
S-Matrix
Feynman diagrams → invariant matrix element iM
long range interaction:
Mfull = Aq 2 (1 + ακ2 q 2 + βκ2 q 2 ln(−q 2 ) + γκ2 q 2 √m
−q 2
+. . . )
R-matrix: R = S − 1
p, pT incoming, pT0 , p0 outgoing momentum:
hp0 |R|pi = (2π)4 δ 4 (p0 + pT0 − p − pT ) iM
Born approximation: nonrelativistic limit position-space potential
V (~r ) = −
1
1
2m1 2m2
Sven Faller
Z
d 3~q i ~q ·~r
e
M
(2π)3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
S-Matrix
Feynman diagrams → invariant matrix element iM
long range interaction:
Mfull = Aq 2 (1 + ακ2 q 2 + βκ2 q 2 ln(−q 2 ) + γκ2 q 2 √m
−q 2
+. . . )
R-matrix: R = S − 1
p, pT incoming, pT0 , p0 outgoing momentum:
hp0 |R|pi = (2π)4 δ 4 (p0 + pT0 − p − pT ) iM
Born approximation: nonrelativistic limit position-space potential
V (~r ) = −
1
1
2m1 2m2
Sven Faller
Z
d 3~q i ~q ·~r
e
M
(2π)3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
S-Matrix
Feynman diagrams → invariant matrix element iM
long range interaction:
Mfull = Aq 2 (1 + ακ2 q 2 + βκ2 q 2 ln(−q 2 ) + γκ2 q 2 √m
−q 2
+. . . )
R-matrix: R = S − 1
p, pT incoming, pT0 , p0 outgoing momentum:
hp0 |R|pi = (2π)4 δ 4 (p0 + pT0 − p − pT ) iM
Born approximation: nonrelativistic limit position-space potential
V (~r ) = −
1
1
2m1 2m2
Sven Faller
Z
d 3~q i ~q ·~r
e
M
(2π)3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
S-Matrix
Feynman diagrams → invariant matrix element iM
long range interaction:
Mfull = Aq 2 (1 + ακ2 q 2 + βκ2 q 2 ln(−q 2 ) + γκ2 q 2 √m
−q 2
+. . . )
R-matrix: R = S − 1
p, pT incoming, pT0 , p0 outgoing momentum:
hp0 |R|pi = (2π)4 δ 4 (p0 + pT0 − p − pT ) iM
Born approximation: nonrelativistic limit position-space potential
V (~r ) = −
1
1
2m1 2m2
Sven Faller
Z
d 3~q i ~q ·~r
e
M
(2π)3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
S-Matrix
Feynman diagrams → invariant matrix element iM
long range interaction:
Mfull = Aq 2 (1 + ακ2 q 2 + βκ2 q 2 ln(−q 2 ) + γκ2 q 2 √m
−q 2
+. . . )
R-matrix: R = S − 1
p, pT incoming, pT0 , p0 outgoing momentum:
hp0 |R|pi = (2π)4 δ 4 (p0 + pT0 − p − pT ) iM
Born approximation: nonrelativistic limit position-space potential
V (~r ) = −
1
1
2m1 2m2
Sven Faller
Z
d 3~q i ~q ·~r
e
M
(2π)3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Expansion: Gravitational Potential
lowest order: V (r ) = −G m1r·m2 (Newton)
higher order effects: O(v 2 /c 2 ), O(Gm/rc 2 )
general form:
G(m1 + m2 )
G m 1 m2
V (r ) = −
1+a·
.
.
.
r
r c2
dimensional analysis: loop diagrams → extra power of
κ2 ∼ G, factor ~
gravitational potential: general form
Gm1 m2
G(m1 + m2 )
G~
V (r ) = −
1+α
+ β 2 3 + ...
r
rc 2
r c
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Expansion: Gravitational Potential
lowest order: V (r ) = −G m1r·m2 (Newton)
higher order effects: O(v 2 /c 2 ), O(Gm/rc 2 )
general form:
G(m1 + m2 )
G m 1 m2
V (r ) = −
1+a·
.
.
.
r
r c2
dimensional analysis: loop diagrams → extra power of
κ2 ∼ G, factor ~
gravitational potential: general form
Gm1 m2
G(m1 + m2 )
G~
V (r ) = −
1+α
+ β 2 3 + ...
r
rc 2
r c
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Expansion: Gravitational Potential
lowest order: V (r ) = −G m1r·m2 (Newton)
higher order effects: O(v 2 /c 2 ), O(Gm/rc 2 )
general form:
G(m1 + m2 )
G m 1 m2
V (r ) = −
1+a·
.
.
.
r
r c2
dimensional analysis: loop diagrams → extra power of
κ2 ∼ G, factor ~
gravitational potential: general form
Gm1 m2
G(m1 + m2 )
G~
V (r ) = −
1+α
+ β 2 3 + ...
r
rc 2
r c
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Expansion: Gravitational Potential
lowest order: V (r ) = −G m1r·m2 (Newton)
higher order effects: O(v 2 /c 2 ), O(Gm/rc 2 )
general form:
G(m1 + m2 )
G m 1 m2
V (r ) = −
1+a·
.
.
.
r
r c2
dimensional analysis: loop diagrams → extra power of
κ2 ∼ G, factor ~
gravitational potential: general form
Gm1 m2
G(m1 + m2 )
G~
V (r ) = −
1+α
+ β 2 3 + ...
r
rc 2
r c
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Expansion: Gravitational Potential
lowest order: V (r ) = −G m1r·m2 (Newton)
higher order effects: O(v 2 /c 2 ), O(Gm/rc 2 )
general form:
G(m1 + m2 )
G m 1 m2
V (r ) = −
1+a·
.
.
.
r
r c2
dimensional analysis: loop diagrams → extra power of
κ2 ∼ G, factor ~
gravitational potential: general form
Gm1 m2
G(m1 + m2 )
G~
V (r ) = −
1+α
+ β 2 3 + ...
r
rc 2
r c
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Tree Level
p
k0
q
iM =
m1
m2
k
= ταβ (k , k 0 ) ·
iP αβγδ
q 2 + i
· τγδ (p, p0 )
p0
nonrelativitstic position space potential
Z
κ2
d 3~q i ~q ·~r 1
κ2
1
V (~r ) = − m1 m2
e
=
−
m1 m2
~q 2
8
8
4πr
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Tree Level
p
k0
q
iM =
m1
m2
k
= ταβ (k , k 0 ) ·
iP αβγδ
q 2 + i
· τγδ (p, p0 )
p0
nonrelativitstic position space potential
Z
κ2
d 3~q i ~q ·~r 1
κ2
1
V (~r ) = − m1 m2
e
=
−
m1 m2
~q 2
8
8
4πr
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Vertex Corrections - Overview
(a)
(b)
=
(c)
+
+
+
(d)
+
(e)
Sven Faller
+
(f)
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
General Form
QED: Ward identiy ⇔ vertex: energy conservation
∂µ T µν = 0
momentum conservation: qµ V µν ≡ 0
general vertex form
k2
q
k1
V µν = h k2 | T µν | k1 i
1 2 µν
µ ν
2
ν µ
= F1 (q ) k1 k2 + k1 k2 + q g
2
µ ν
2
µν 2
+ F2 (q ) q q − g q .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
General Form
QED: Ward identiy ⇔ vertex: energy conservation
∂µ T µν = 0
momentum conservation: qµ V µν ≡ 0
general vertex form
k2
q
k1
V µν = h k2 | T µν | k1 i
1 2 µν
µ ν
2
ν µ
= F1 (q ) k1 k2 + k1 k2 + q g
2
µ ν
2
µν 2
+ F2 (q ) q q − g q .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
General Form
QED: Ward identiy ⇔ vertex: energy conservation
∂µ T µν = 0
momentum conservation: qµ V µν ≡ 0
general vertex form
k2
q
k1
V µν = h k2 | T µν | k1 i
1 2 µν
µ ν
2
ν µ
= F1 (q ) k1 k2 + k1 k2 + q g
2
µ ν
2
µν 2
+ F2 (q ) q q − g q .
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Form Factors
tree-level limit
−−−−−−−−→
normalization condition: F1 ≡ 0
F2 no normalization condition
form factors dimensionless
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Form Factors
tree-level limit
−−−−−−−−→
normalization condition: F1 ≡ 0
F2 no normalization condition
form factors dimensionless
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Form Factors
tree-level limit
−−−−−−−−→
normalization condition: F1 ≡ 0
F2 no normalization condition
form factors dimensionless
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Feynman Rules
Scattering
Potential
Vertex Corrections
Form Factors
tree-level limit
−−−−−−−−→
normalization condition: F1 ≡ 0
F2 no normalization condition
form factors dimensionless
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
First Loop Diagram
k2
q
←−
x
`
µν
m
k1
d 4`
1
(2π)4 `2 (` − q)2 [(` − k2 )2 − m2 ]
µν
· τρσ (k2 − `, k2 , m) τλκ (k1 , k2 − `, m) ταβγδ
(`, q) .
= iP
σραβ
iP
γδλκ
Z
i
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Results
form factor F1 (q 2 )
result from
our
Donoghue
Akhundov et al.
ln(−q 2 )
- 3/4
- 3/4
- 5/4
2
π
√
m
−q 2
1/16
1/16
- 1/16
form factor F2 (q 2 )
result from
our
Donoghue
Akhundov et al.
Sven Faller
ln(−q 2 )
7/3
3
-7/3
2
π
√
m
−q 2
7/8
7/8
- 7/8
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Results
form factor F1 (q 2 )
result from
our
Donoghue
Akhundov et al.
ln(−q 2 )
- 3/4
- 3/4
- 5/4
2
π
√
m
−q 2
1/16
1/16
- 1/16
form factor F2 (q 2 )
result from
our
Donoghue
Akhundov et al.
Sven Faller
ln(−q 2 )
7/3
3
-7/3
2
π
√
m
−q 2
7/8
7/8
- 7/8
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Second Loop Diagram
x
µν
`
k2
m
k1
= iP
αβλκ
iP
γδρσ
Z
Vαβγδ
Sven Faller
µν
d 4 ` τλκρσ (`, q)
(2π)4 `2 (` − q)2
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Results
form factor F1 (q 2 )
result from
our
Donoghue
Akhundov et al.
ln(−q 2 )
0
0
0
2
π
√
m
−q 2
0
0
0
form factor F2 (q 2 )
result from
our
Donoghue
Akhundov et al.
Sven Faller
ln(−q 2 )
-13/3
-13/3
7/3
2
π
√
m
−q 2
0
0
0
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Results
form factor F1 (q 2 )
result from
our
Donoghue
Akhundov et al.
ln(−q 2 )
0
0
0
2
π
√
m
−q 2
0
0
0
form factor F2 (q 2 )
result from
our
Donoghue
Akhundov et al.
Sven Faller
ln(−q 2 )
-13/3
-13/3
7/3
2
π
√
m
−q 2
0
0
0
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Result: Vertex Correction
form factors
»
–
3
1 π2 m
κ2 q 2
2
p
−
ln(−q
)
+
,
32π 2
4
16
−q 2
–
»
κ2 m2
7 π2 m
2
p
.
F2 (q 2 ) =
−2
ln(−q
)
+
32π 2
8
−q 2
F1 (q 2 ) = 1 +
tree-level normalized → factor κ/2i
V µν = −
«–„
»
„
«
κ2 q 2
3
iκ
1 π2 m
1 2 µν
µ ν
2
ν µ
p
1+
−
ln(−q
)
+
k
k
+
k
k
+
q
η
1 2
1 2
2
32π 2
4
16
2
−q 2
»
–
„
«
2m
7
π
1
κ3 m2
−
−2 ln(−q 2 ) + p
q µ q ν − q 2 η µν .
64π 2
8
2
−q 2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Result: Vertex Correction
form factors
»
–
3
1 π2 m
κ2 q 2
2
p
−
ln(−q
)
+
,
32π 2
4
16
−q 2
–
»
κ2 m2
7 π2 m
2
p
.
F2 (q 2 ) =
−2
ln(−q
)
+
32π 2
8
−q 2
F1 (q 2 ) = 1 +
tree-level normalized → factor κ/2i
V µν = −
«–„
»
„
«
κ2 q 2
3
iκ
1 π2 m
1 2 µν
µ ν
2
ν µ
p
1+
−
ln(−q
)
+
k
k
+
k
k
+
q
η
1 2
1 2
2
32π 2
4
16
2
−q 2
»
–
„
«
2m
7
π
1
κ3 m2
−
−2 ln(−q 2 ) + p
q µ q ν − q 2 η µν .
64π 2
8
2
−q 2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Vacuum Polarisation - Diagrams
=
+
(a)
+
(b)
(c)
vacuum polarisation tensor Παβγδ → graviton propagator
correction
∆αβγδ + ∆αβµν iΠµνρσ ∆ρσγδ
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Vacuum Polarization
counter-term, graviton self energy and ghost
→ Veltman and ’t Hooft (1974)
matter loop
»
´`
´
´
i κ2
−1 ` α β
1 ` α γ
q q − q 2 η αβ q γ q δ − q 2 η γδ −
q q − q 2 η αγ
32π 2 4
5
30
–
`
´
´`
´
1 ` α δ
· q β q δ − q 2 η βδ −
q q − q 2 η αδ q β q γ − q 2 η βγ − 2m34 η αβ η γδ
30
ff
´ 2
`
´
2 2 αβ ` γδ 2
− m3 η
η q − q γ q δ − m32 η γδ η αβ q 2 − q α q β
ln(−q 2 )
3
3
Π̃αβγδ =
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Vacuum Polarization
counter-term, graviton self energy and ghost
→ Veltman and ’t Hooft (1974)
matter loop
»
´`
´
´
i κ2
−1 ` α β
1 ` α γ
q q − q 2 η αβ q γ q δ − q 2 η γδ −
q q − q 2 η αγ
32π 2 4
5
30
–
`
´
´`
´
1 ` α δ
· q β q δ − q 2 η βδ −
q q − q 2 η αδ q β q γ − q 2 η βγ − 2m34 η αβ η γδ
30
ff
´ 2
`
´
2 2 αβ ` γδ 2
− m3 η
η q − q γ q δ − m32 η γδ η αβ q 2 − q α q β
ln(−q 2 )
3
3
Π̃αβγδ =
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
One Particle Irreduzible Diagrams
k2
q
k10
=
k1
+
k20
q
+
Sven Faller
+
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Gravitational Potential
1PI-diagrams → S-matrix contributions
ˆ
˜
4µναβ iΠαβγδ 4 γδρσ V2ρσ (k10 , k20 , −q, m)
iM = V1µν (k1 , k2 , q, m1 ) 4 µνρσ +4
position space gravitational potential
G m1 m2
G(m1 + m2 ) 167 G ~
V (r ) = −
1−
−
r
30π r 2 c3
r c2
include massless Neutrino-loop
gravitational potential
G m1 m2
G(m1 + m2 )
167
Nν
G~
V (r ) = −
1−
−
+
r
30π 40π r 2 c3
r c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Gravitational Potential
1PI-diagrams → S-matrix contributions
ˆ
˜
4µναβ iΠαβγδ 4 γδρσ V2ρσ (k10 , k20 , −q, m)
iM = V1µν (k1 , k2 , q, m1 ) 4 µνρσ +4
position space gravitational potential
G m1 m2
G(m1 + m2 ) 167 G ~
V (r ) = −
1−
−
r
30π r 2 c3
r c2
include massless Neutrino-loop
gravitational potential
G m1 m2
G(m1 + m2 )
167
Nν
G~
V (r ) = −
1−
−
+
r
30π 40π r 2 c3
r c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Gravitational Potential
1PI-diagrams → S-matrix contributions
ˆ
˜
4µναβ iΠαβγδ 4 γδρσ V2ρσ (k10 , k20 , −q, m)
iM = V1µν (k1 , k2 , q, m1 ) 4 µνρσ +4
position space gravitational potential
G m1 m2
G(m1 + m2 ) 167 G ~
V (r ) = −
1−
−
r
30π r 2 c3
r c2
include massless Neutrino-loop
gravitational potential
G m1 m2
G(m1 + m2 )
167
Nν
G~
V (r ) = −
1−
−
+
r
30π 40π r 2 c3
r c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Gravitational Potential (so far)
our result:
V (r ) = −
167
G m1 m2
G(m1 + m2 )
Nν
G~
−
1−
+
r
30π 40π r 2 c3
r c2
Donoghue
G m1 m2
G(m1 + m2 ) (135 + 2Nν ) G ~
V (r ) = −
1−
−
.
r
r c2
30π 2
r c3
Akhundov et al.
G m1 m2
G(m1 + m2 )
107 G ~
V (r ) = −
1+
−
r
r c2
30π 2 r 2 c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Further Potential Definition
Hamber and Liu (1995)
m1
q
m2
m1
Sven Faller
m2
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Further Contributions
double-seagull diagramm:
V4
G m1 m2 2G(m1 + m2 ) 14 G ~
=−
−
r
π r 2 c3
r c2
triangle diagrams:
Vi◦h
Sven Faller
G m1 m2 11 G ~
=−
r
2π r 2 c3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Further Contributions
double-seagull diagramm:
V4
G m1 m2 2G(m1 + m2 ) 14 G ~
=−
−
r
π r 2 c3
r c2
triangle diagrams:
Vi◦h
Sven Faller
G m1 m2 11 G ~
=−
r
2π r 2 c3
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Further Contributions
cross-boxed diagramms (Bjerrum-Bohr 2003)
+
V (r ) = −
47 m1 m2 G2
.
3
π r3
Gravitational Potential
G m1 m2
G(m1 + m2 ) 64 + Nν G ~
V (r ) = −
1+
−
r
40π r 2 c3
r c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Further Contributions
cross-boxed diagramms (Bjerrum-Bohr 2003)
+
V (r ) = −
47 m1 m2 G2
.
3
π r3
Gravitational Potential
G m1 m2
G(m1 + m2 ) 64 + Nν G ~
V (r ) = −
1+
−
r
40π r 2 c3
r c2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Summary
full theory of quantum gravity unknown
effective field theory of gravity
low energy effects separated from high-energy effects
one-loop order quantum predictions
evaluate leading quantum corrections → effective potential
and Schwarzschild-metric
understanding quantum nature of gravity
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Thanks
supervisor: Prof. Dr. T. Mannel
second supervisor: Dr. A. Khodjamirian
for usefull tips and discussions
Dr. Th. Feldmann
Dr. E. Bjerrum-Bohr
Prof. Dr. F. Donoghue
Dipl.-Phys. M. Jung
Dipl.-Phys. N. Offen
Dipl.-Phys. K. Grybel
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion - Affine Connection
background field method: metric expansion
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
affine connection: Γλµν = Γ̄λµν + −Γλµν + =Γλµν
with
1
Γ̄λµν = ḡ λσ ∂µ ḡσν + ∂ν ḡσµ − ∂σ ḡµν
2
κ λσ
λ
ḡ
D
h
+
D
h
−
D
h
Γ
=
µ
σν
ν
σµ
σ
µν
µν
−
2
κ2 λγ
λ
Γ
=
−
h Dµ hγν + Dν hµγ − Dγ hµν
µν
=
2
Sven Faller
(O(h0 )) ,
(O(h1 )) ,
(O(h2 )) .
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion - Affine Connection
background field method: metric expansion
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
affine connection: Γλµν = Γ̄λµν + −Γλµν + =Γλµν
with
1
Γ̄λµν = ḡ λσ ∂µ ḡσν + ∂ν ḡσµ − ∂σ ḡµν
2
κ λσ
λ
ḡ
D
h
+
D
h
−
D
h
Γ
=
µ
σν
ν
σµ
σ
µν
µν
−
2
κ2 λγ
λ
Γ
=
−
h Dµ hγν + Dν hµγ − Dγ hµν
µν
=
2
Sven Faller
(O(h0 )) ,
(O(h1 )) ,
(O(h2 )) .
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion - Affine Connection
background field method: metric expansion
gµν = ḡµν + κhµν
g µν = ḡ µν − κhµν + κ2 hλµ hλν + . . .
affine connection: Γλµν = Γ̄λµν + −Γλµν + =Γλµν
with
1
Γ̄λµν = ḡ λσ ∂µ ḡσν + ∂ν ḡσµ − ∂σ ḡµν
2
κ λσ
λ
ḡ
D
h
+
D
h
−
D
h
Γ
=
µ
σν
ν
σµ
σ
µν
µν
−
2
κ2 λγ
λ
Γ
=
−
h Dµ hγν + Dν hµγ − Dγ hµν
µν
=
2
Sven Faller
(O(h0 )) ,
(O(h1 )) ,
(O(h2 )) .
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion: Curvature
Riemann curvature tensor:
β
β
β
β
β
λ
β
λ
R βαµν = Dµ Γβ
αν − Dν Γαµ + Γαν Γλµ − Γαµ Γλν ≡ R̄ αµν + R αµν + R
= αµν
−
Ricci scalar:
R = ḡ αµ R
− κhαµ Rαµ + κ2 hγα hγµ R̄αµ
= αµ
−

´˜
1 ` β µ γ´ 1 ˆ β`
µ
2
= κ − Dµ hγ D hβ + Dβ hν 2Dµ hνµ − Dν hµ
2
2
´`
´
1`
ν
ν
+
Dµ hβ
+ Dβ hµ
− Dν hµβ Dµ hνβ + Dν hβµ − Dβ hνµ
4
´
1`
1
β
β
µ
−
2Dµ hνµ − Dν hµ
Dν hβ
− hαµ Dµ Dα hβ
4
2
ff
´
1 µ ` α β
α
β α µ
+ hα
Dβ D hµ + Dµ hβα − Dβ hµ
+ κ2 hµ
hβ R̄α
2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion: Curvature
Riemann curvature tensor:
β
β
β
β
β
λ
β
λ
R βαµν = Dµ Γβ
αν − Dν Γαµ + Γαν Γλµ − Γαµ Γλν ≡ R̄ αµν + R αµν + R
= αµν
−
Ricci scalar:
R = ḡ αµ R
− κhαµ Rαµ + κ2 hγα hγµ R̄αµ
= αµ
−

´˜
1 ` β µ γ´ 1 ˆ β`
µ
2
= κ − Dµ hγ D hβ + Dβ hν 2Dµ hνµ − Dν hµ
2
2
´`
´
1`
ν
ν
+
Dµ hβ
+ Dβ hµ
− Dν hµβ Dµ hνβ + Dν hβµ − Dβ hνµ
4
´
1`
1
β
β
µ
−
2Dµ hνµ − Dν hµ
Dν hβ
− hαµ Dµ Dα hβ
4
2
ff
´
1 µ ` α β
α
β α µ
+ hα
Dβ D hµ + Dµ hβα − Dβ hµ
+ κ2 hµ
hβ R̄α
2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Gauge Fixing and Ghost Field
Yang-Mills field theory
gauge fixing
introduce Fadeev-Popov ghost fields
gauge fixing Lagrangian (’t Hoof and Veltman 1974)
p
1
1 µ
ν
µλ
Lgf = −ḡ
D hµν − Dµ h Dλ h − D h
2
2
ghost field Lagrangian (ebd.)
p
Lghost = −ḡ η ?µ Dλ Dλ ḡµν − R̄µν η ν
complex ghostfield η: only contribution from vacuum
polarization to the graviton propagator
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Field Theories - Overview
renormalizabel and non-renormalizable field theories
general form of the Lagrangian
L = L(c1 , c2 , . . . , cn )
low energy structure determined by finite parameters
c1 , c2 , . . . cn
two different typs of quantum field theories
asympotically free theories - ultraviolet stable theories
ultraviolet unstable theories
ultraviolet unstable theories low energy limit of
fundamental theory - no difference between renormalizable
and effective non-renormalizable theory
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Field Theory
two different types of effecive field theories
decoupling effective field theories
heavy degrees of freedom integrated out
effective level no light particles
Lagrangian general form
X 1 X
giD OiD
Leff = LD≤4 +
ΛD−4
D>4
iD
non-decoupling effective field theories
fundamental to effective level by phase transistion
spontaneously broken symmetry → light pseudo-Goldstone
bosons
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective General Relativity
quantization process: first order curvature
renormalization higher order needed
one-loop Feynman rules → higher order curvature no
contribution
gravitational action
S = Svac + Sm + Sgf + Sghost
Z
2R
4 √
= d x −g
+ Lm + Lgf + Lghost
κ2
quantum degrees of freedom: gravitation field hµν ,
ghostfields ηµ , ηµ∗
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective General Relativity
quantization process: first order curvature
renormalization higher order needed
one-loop Feynman rules → higher order curvature no
contribution
gravitational action
S = Svac + Sm + Sgf + Sghost
Z
2R
4 √
= d x −g
+ Lm + Lgf + Lghost
κ2
quantum degrees of freedom: gravitation field hµν ,
ghostfields ηµ , ηµ∗
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective General Relativity
quantization process: first order curvature
renormalization higher order needed
one-loop Feynman rules → higher order curvature no
contribution
gravitational action
S = Svac + Sm + Sgf + Sghost
Z
2R
4 √
= d x −g
+ Lm + Lgf + Lghost
κ2
quantum degrees of freedom: gravitation field hµν ,
ghostfields ηµ , ηµ∗
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective General Relativity
quantization process: first order curvature
renormalization higher order needed
one-loop Feynman rules → higher order curvature no
contribution
gravitational action
S = Svac + Sm + Sgf + Sghost
Z
2R
4 √
= d x −g
+ Lm + Lgf + Lghost
κ2
quantum degrees of freedom: gravitation field hµν ,
ghostfields ηµ , ηµ∗
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective General Relativity
quantization process: first order curvature
renormalization higher order needed
one-loop Feynman rules → higher order curvature no
contribution
gravitational action
S = Svac + Sm + Sgf + Sghost
Z
2R
4 √
= d x −g
+ Lm + Lgf + Lghost
κ2
quantum degrees of freedom: gravitation field hµν ,
ghostfields ηµ , ηµ∗
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Effective Quantum Gravity
R
√ Sgrav = d 4 x −g κ22 R + c1 R 2 + c2 Rµν R µν + · · · + Lm
parameter ci
finite number
values unknown
free parameters
low-energy limit: effective quantum gravity
Z
2
4 √
2
µν
Sgrav = d x −g 2 R + c1 R + c2 Rµν R + Lm
κ
higher energy: theory renormalization
value of c1 , c2 shifted → renormalization effects absorbed
by parameters
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Contributions
gravitational contributions
(0)
(2)
Lgr (Λ) ,
Lgr (R) ,
(4)
Lgr (R 2 )
matter field
scalar matter field:
(0)
Lm (φ, m) ,
(2)
Lm (φ, m, R)
massless matter field:
(0)
L̄m = 0 ,
(2)
L̄m (φ, R) ,
Sven Faller
(0)
L̄m (φ, R, R 2 )
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Contributions
gravitational contributions
(0)
(2)
Lgr (Λ) ,
Lgr (R) ,
(4)
Lgr (R 2 )
matter field
scalar matter field:
(0)
Lm (φ, m) ,
(2)
Lm (φ, m, R)
massless matter field:
(0)
L̄m = 0 ,
(2)
L̄m (φ, R) ,
Sven Faller
(0)
L̄m (φ, R, R 2 )
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Contributions
gravitational contributions
(0)
(2)
Lgr (Λ) ,
Lgr (R) ,
(4)
Lgr (R 2 )
matter field
scalar matter field:
(0)
Lm (φ, m) ,
(2)
Lm (φ, m, R)
massless matter field:
(0)
L̄m = 0 ,
(2)
L̄m (φ, R) ,
Sven Faller
(0)
L̄m (φ, R, R 2 )
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Contributions
gravitational contributions
(0)
(2)
Lgr (Λ) ,
Lgr (R) ,
(4)
Lgr (R 2 )
matter field
scalar matter field:
(0)
Lm (φ, m) ,
(2)
Lm (φ, m, R)
massless matter field:
(0)
L̄m = 0 ,
(2)
L̄m (φ, R) ,
Sven Faller
(0)
L̄m (φ, R, R 2 )
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Counter Terms
loop-diagrams → UV-divergencies
UV-divergencies separated non-divergent parts by
constant ci and di regulation
one-loop order: Veltman and ’t Hoof (1974)
(1)
LM
p
ff

−ḡ
1
7
2
µν
=
R̄ +
R̄µν R̄
8π 2 120
20
with
=4−D
MS-scheme
(r )
c1 = c1 +
1
960π 2 and
(r )
c2 = c2 +
7
160π 2 two-loop order
(2)
LM =
209κ
1p
−ḡ R αβγδ R γδρσ R ρσαβ
2
2
2880(16π ) Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Counter Terms
loop-diagrams → UV-divergencies
UV-divergencies separated non-divergent parts by
constant ci and di regulation
one-loop order: Veltman and ’t Hoof (1974)
(1)
LM
p
ff

−ḡ
1
7
2
µν
=
R̄ +
R̄µν R̄
8π 2 120
20
with
=4−D
MS-scheme
(r )
c1 = c1 +
1
960π 2 and
(r )
c2 = c2 +
7
160π 2 two-loop order
(2)
LM =
209κ
1p
−ḡ R αβγδ R γδρσ R ρσαβ
2
2
2880(16π ) Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Counter Terms
loop-diagrams → UV-divergencies
UV-divergencies separated non-divergent parts by
constant ci and di regulation
one-loop order: Veltman and ’t Hoof (1974)
(1)
LM
p
ff

−ḡ
1
7
2
µν
=
R̄ +
R̄µν R̄
8π 2 120
20
with
=4−D
MS-scheme
(r )
c1 = c1 +
1
960π 2 and
(r )
c2 = c2 +
7
160π 2 two-loop order
(2)
LM =
209κ
1p
−ḡ R αβγδ R γδρσ R ρσαβ
2
2
2880(16π ) Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Counter Terms
loop-diagrams → UV-divergencies
UV-divergencies separated non-divergent parts by
constant ci and di regulation
one-loop order: Veltman and ’t Hoof (1974)
(1)
LM
p
ff

−ḡ
1
7
2
µν
=
R̄ +
R̄µν R̄
8π 2 120
20
with
=4−D
MS-scheme
(r )
c1 = c1 +
1
960π 2 and
(r )
c2 = c2 +
7
160π 2 two-loop order
(2)
LM =
209κ
1p
−ḡ R αβγδ R γδρσ R ρσαβ
2
2
2880(16π ) Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Counter Terms
loop-diagrams → UV-divergencies
UV-divergencies separated non-divergent parts by
constant ci and di regulation
one-loop order: Veltman and ’t Hoof (1974)
(1)
LM
p
ff

−ḡ
1
7
2
µν
=
R̄ +
R̄µν R̄
8π 2 120
20
with
=4−D
MS-scheme
(r )
c1 = c1 +
1
960π 2 and
(r )
c2 = c2 +
7
160π 2 two-loop order
(2)
LM =
209κ
1p
−ḡ R αβγδ R γδρσ R ρσαβ
2
2
2880(16π ) Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Evaluation Vertex Factors
momentum space vertex factors
Z
Vµ1 ν1 ,...,µm νn = +i
d 4 x d 4 x1 . . . d 4 xn d 4 y1 . . . d 4 ym ei(p1 x1 +···+pn xn +q1 y1 +···+qm ym )
δ
δ
δ
δ
· ... ·
· ... ·
·
µm νm
δJ1 (x1 )
δJn (xn ) δH1ν1 µ1 (y1 )
δHm
(ym )
´
`
· Lint φ1 , . . . , φn , H1 , . . . Hm (x)
·
sources of gravity: J1 , . . . , Jn
µm νm
external and internal gravity field: H1µ1 ν1 , . . . , Hm
incoming p1 , . . . , pn , outgoing q1 , . . . qm momentum
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Evaluation Vertex Factors
momentum space vertex factors
Z
Vµ1 ν1 ,...,µm νn = +i
d 4 x d 4 x1 . . . d 4 xn d 4 y1 . . . d 4 ym ei(p1 x1 +···+pn xn +q1 y1 +···+qm ym )
δ
δ
δ
δ
· ... ·
· ... ·
·
µm νm
δJ1 (x1 )
δJn (xn ) δH1ν1 µ1 (y1 )
δHm
(ym )
´
`
· Lint φ1 , . . . , φn , H1 , . . . Hm (x)
·
sources of gravity: J1 , . . . , Jn
µm νm
external and internal gravity field: H1µ1 ν1 , . . . , Hm
incoming p1 , . . . , pn , outgoing q1 , . . . qm momentum
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Evaluation Vertex Factors
momentum space vertex factors
Z
Vµ1 ν1 ,...,µm νn = +i
d 4 x d 4 x1 . . . d 4 xn d 4 y1 . . . d 4 ym ei(p1 x1 +···+pn xn +q1 y1 +···+qm ym )
δ
δ
δ
δ
· ... ·
· ... ·
·
µm νm
δJ1 (x1 )
δJn (xn ) δH1ν1 µ1 (y1 )
δHm
(ym )
´
`
· Lint φ1 , . . . , φn , H1 , . . . Hm (x)
·
sources of gravity: J1 , . . . , Jn
µm νm
external and internal gravity field: H1µ1 ν1 , . . . , Hm
incoming p1 , . . . , pn , outgoing q1 , . . . qm momentum
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Evaluation Vertex Factors
momentum space vertex factors
Z
Vµ1 ν1 ,...,µm νn = +i
d 4 x d 4 x1 . . . d 4 xn d 4 y1 . . . d 4 ym ei(p1 x1 +···+pn xn +q1 y1 +···+qm ym )
δ
δ
δ
δ
· ... ·
· ... ·
·
µm νm
δJ1 (x1 )
δJn (xn ) δH1ν1 µ1 (y1 )
δHm
(ym )
´
`
· Lint φ1 , . . . , φn , H1 , . . . Hm (x)
·
sources of gravity: J1 , . . . , Jn
µm νm
external and internal gravity field: H1µ1 ν1 , . . . , Hm
incoming p1 , . . . , pn , outgoing q1 , . . . qm momentum
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Graviton-Graviton-Scalar-Vertex
Lagrangian O(h2 )
(2)
Lm = κ2
„
1 µν ν
1
h h λ− hhµν
2
4
«
∂µ φ∂ν φ−
vertex factor
Z
Vηλρσ = +i
„
«
ˆ
˜
1
κ2
hλσ hλσ − hh ∂µ φ∂ µ φ−m2 φ2
8
2
d 4 x d 4 x1 d 4 x2 d 4 x3 d 4 x4 ei(px1 −p
0
x2 +kx3 −kx4 )
∂
∂
∂
∂
·
·
·
∂φ(x1 ) ∂φ(x2 ) ∂hηλ (x3 ) ∂hρσ (x4 )
»
–
´ α
κ2 ηλ
1`
δ
·
h
1ηλαδ 1ρσβ −
ηηλ 1ρσαβ + ηρσ 1ηλαβ ∂ φ(x)∂ β φ(x)
2
4
„
«
ff
˜
ˆ
1
1
1
−
1ηλρσ − ηηλ − ηηλ ηρσ ∂ γ φ(x)∂γ φ(x) − m2 φ(x)2 hρσ
4
2
2
·
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Graviton-Graviton-Scalar-Vertex
Lagrangian O(h2 )
(2)
Lm = κ2
„
1 µν ν
1
h h λ− hhµν
2
4
«
∂µ φ∂ν φ−
vertex factor
Z
Vηλρσ = +i
„
«
ˆ
˜
1
κ2
hλσ hλσ − hh ∂µ φ∂ µ φ−m2 φ2
8
2
d 4 x d 4 x1 d 4 x2 d 4 x3 d 4 x4 ei(px1 −p
0
x2 +kx3 −kx4 )
∂
∂
∂
∂
·
·
·
∂φ(x1 ) ∂φ(x2 ) ∂hηλ (x3 ) ∂hρσ (x4 )
»
–
´ α
κ2 ηλ
1`
δ
·
h
1ηλαδ 1ρσβ −
ηηλ 1ρσαβ + ηρσ 1ηλαβ ∂ φ(x)∂ β φ(x)
2
4
„
«
ff
˜
ˆ
1
1
1
−
1ηλρσ − ηηλ − ηηλ ηρσ ∂ γ φ(x)∂γ φ(x) − m2 φ(x)2 hρσ
4
2
2
·
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Graviton-Graviton-Scalar-Vertex
ηλ
`0
-
p0
`%
p
ρσ
»
–
´ ` α 0β
´
1`
iκ2
1ηλαδ 1ρσβ δ −
ηηλ 1ρσαβ + ηρσ 1ηλαβ
p p + pβ p0α
2
4
»
–
ff
`
´
1
1
−
1ηλρσ − ηηλ ηρσ (p · p0 ) − m2
2
2
Vηλρσ =
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Three-Graviton-Vertex
µν
ταβγδ (k , q) = −
iκ
2
–

»
3 µν 2
µ ν
µ
ν
µ ν
Pαβγδ k k + (k − q) (k − q) + q q + η q
2
ˆ
σλ
µν
σλ
µν
µσ
νλ
µσ
νλ ˜
+ 2qλ qσ 1αβ
1γδ
+ 1γδ
1αβ
− 1αβ
1γδ
− 1γδ
1αβ
ˆ
µλ
µλ ´
νλ
νλ ´
ν`
µ`
+ qλ q ηαβ 1γδ
+ ηγδ 1αβ
+ ηγδ 1αβ
+ qλ q ηαβ 1γδ
`
µν
µν ´
σλ
σλ ´˜
2`
µν
+ ηγδ 1αβ
− q ηαβ 1γδ
+ ηγδ 1αβ
− η qλ qσ ηαβ 1γδ
ˆ
˘
λσ
ν
λσ
µ
µ
ν
+ 2qλ 1αβ
1γδσ (k − q) + 1αβ
1γδσ (k − q)
λσ
ν µ
λσ
µ ν¯
1αβσ k − 1γδ
1αβσ k
− 1γδ
` λρ
σ
λρ
σ ´˜
µ
νσ
νσ
µ´
µν
2`
+ η qσ qλ 1αβ 1γδρ + 1γδ 1αβρ
+ 1αβ 1γδσ
+ q 1αβσ 1γδ

»
–
1 µν
` 2
´
µσ
ν
νσ
µ
+
k + (k − q) 1αβ
1γδσ + 1γδ 1αβσ − η Pαβγδ
2
ff
ffff
`
µν
µν
2
2´
− 1γδ ηαβ k − 1αβ ηγδ (k − q)
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Born approximation
p
covariant normalized: hp0 |pi = 2Ep δ 3 (~p − ~p0 ), Ep = m2 + ~p2
Born approximation: hp0 |pi = −i Ṽ (~q )(2π)δ(E~p0 − E~p )
nonrelativistic limit: interaction potential
Z 3
d ~pT 3 0
1
1
~
−Ṽ (q ) = M
δ (~p + ~p)
2m1 2m2
(2π)3
nonrelativistic limit: Ṽ (~q ) = − 2m11·2m2 M
Fourier transformation to position-space:
nonrelativistic limit: position-space potential
Z
1
1
d 3~q i ~q ·~r
V (~r ) = −
e
M
2m1 2m2
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Born approximation
p
covariant normalized: hp0 |pi = 2Ep δ 3 (~p − ~p0 ), Ep = m2 + ~p2
Born approximation: hp0 |pi = −i Ṽ (~q )(2π)δ(E~p0 − E~p )
nonrelativistic limit: interaction potential
Z 3
d ~pT 3 0
1
1
~
−Ṽ (q ) = M
δ (~p + ~p)
2m1 2m2
(2π)3
nonrelativistic limit: Ṽ (~q ) = − 2m11·2m2 M
Fourier transformation to position-space:
nonrelativistic limit: position-space potential
Z
1
1
d 3~q i ~q ·~r
V (~r ) = −
e
M
2m1 2m2
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Born approximation
p
covariant normalized: hp0 |pi = 2Ep δ 3 (~p − ~p0 ), Ep = m2 + ~p2
Born approximation: hp0 |pi = −i Ṽ (~q )(2π)δ(E~p0 − E~p )
nonrelativistic limit: interaction potential
Z 3
d ~pT 3 0
1
1
~
−Ṽ (q ) = M
δ (~p + ~p)
2m1 2m2
(2π)3
nonrelativistic limit: Ṽ (~q ) = − 2m11·2m2 M
Fourier transformation to position-space:
nonrelativistic limit: position-space potential
Z
1
1
d 3~q i ~q ·~r
V (~r ) = −
e
M
2m1 2m2
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Born approximation
p
covariant normalized: hp0 |pi = 2Ep δ 3 (~p − ~p0 ), Ep = m2 + ~p2
Born approximation: hp0 |pi = −i Ṽ (~q )(2π)δ(E~p0 − E~p )
nonrelativistic limit: interaction potential
Z 3
d ~pT 3 0
1
1
~
−Ṽ (q ) = M
δ (~p + ~p)
2m1 2m2
(2π)3
nonrelativistic limit: Ṽ (~q ) = − 2m11·2m2 M
Fourier transformation to position-space:
nonrelativistic limit: position-space potential
Z
1
1
d 3~q i ~q ·~r
V (~r ) = −
e
M
2m1 2m2
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Born approximation
p
covariant normalized: hp0 |pi = 2Ep δ 3 (~p − ~p0 ), Ep = m2 + ~p2
Born approximation: hp0 |pi = −i Ṽ (~q )(2π)δ(E~p0 − E~p )
nonrelativistic limit: interaction potential
Z 3
d ~pT 3 0
1
1
~
−Ṽ (q ) = M
δ (~p + ~p)
2m1 2m2
(2π)3
nonrelativistic limit: Ṽ (~q ) = − 2m11·2m2 M
Fourier transformation to position-space:
nonrelativistic limit: position-space potential
Z
1
1
d 3~q i ~q ·~r
V (~r ) = −
e
M
2m1 2m2
(2π)3
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Expansion Form Factors
dimensionless combinations: κ2 m2 , κ2 q 2
expansion:
s
«
(−q 2 )
m2
F1 (q ) = 1 + d1 q + κ q l1 + l2 ln
+
l
+
.
.
.
,
3
µ2
−q 2
s
„
«
(−q 2 )
m2
2
2
2 2
F2 (q ) = −4(d2 − d3 )m + κ m l4 + l5 ln
+ l6
+ ...
µ2
−q 2
2
2
2 2
„
(2)
di : Lm contributions
li : one-loop contributions
l1 , l4 : divergent high enery contributions
l2 , l3 , l5 , l6 : finite non-analytic low energy contributions
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Renormalization
combination l1 , l4 and di → renormalized values
d1 (r) (µ2 ) = d1 + κ2 l1
d2 (r) (µ2 ) + d3 (r) (µ2 ) = d2 + d3 − κ2
l4
4
experiments: measure renormalized values
di(r) (µ2 ) → measured values depend on µ2 choice in
logarithms but all physics independent of µ2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Renormalization
combination l1 , l4 and di → renormalized values
d1 (r) (µ2 ) = d1 + κ2 l1
d2 (r) (µ2 ) + d3 (r) (µ2 ) = d2 + d3 − κ2
l4
4
experiments: measure renormalized values
di(r) (µ2 ) → measured values depend on µ2 choice in
logarithms but all physics independent of µ2
Sven Faller
General Relativity as an Effective Field Theory
Introduction
Quantum Gravity
Effective Field Theory of Gravity
Leading Quantum Corrections
Evaluation of the Vertex Corrections
Gravitational Potential
Potential Definitions
Summary
Effective Gravity
Renormalization
combination l1 , l4 and di → renormalized values
d1 (r) (µ2 ) = d1 + κ2 l1
d2 (r) (µ2 ) + d3 (r) (µ2 ) = d2 + d3 − κ2
l4
4
experiments: measure renormalized values
di(r) (µ2 ) → measured values depend on µ2 choice in
logarithms but all physics independent of µ2
Sven Faller
General Relativity as an Effective Field Theory