Effective Field Theories, Reductionism and Scientific Explanation
... which higher-order quantities that are still invariant under general coordinate transformations have to be added, to account for the physics at higher energies (Donoghue, 1994a,b). The resulting EFTs include quantum corrections to Einstein’s theory which are considered to be footprints of a quantum ...
... which higher-order quantities that are still invariant under general coordinate transformations have to be added, to account for the physics at higher energies (Donoghue, 1994a,b). The resulting EFTs include quantum corrections to Einstein’s theory which are considered to be footprints of a quantum ...
Y-Bias and Angularity
... these interactions to be robust, it must not only accommodate phenomena which are known to occur and all rigorously documented phenomena, predict phenomena which are as-yet undiscovered, and allow for the inclusion of all rigorously observed, impeccably documented, accurately reported data derived f ...
... these interactions to be robust, it must not only accommodate phenomena which are known to occur and all rigorously documented phenomena, predict phenomena which are as-yet undiscovered, and allow for the inclusion of all rigorously observed, impeccably documented, accurately reported data derived f ...
Quasiparticles in the Quantum Hall Effect Janik Kailasvuori Stockholm University
... the quantum Hall system. The main parts of the thesis is intended for quantum Hall physicists, but in this introductory chapter I will present the central ideas in a non-technical way. This very first section tries to convey to the general audience why this kind of research is interesting. The quant ...
... the quantum Hall system. The main parts of the thesis is intended for quantum Hall physicists, but in this introductory chapter I will present the central ideas in a non-technical way. This very first section tries to convey to the general audience why this kind of research is interesting. The quant ...
5. Chern-Simons Theories
... requirements. There’s still an infinite number of them but there’s a simple organising principle. Because we’re interested in small electric and magnetic fields, which vary only over long distances, the most important terms will be those with the fewest powers of A and the fewest derivatives. Our go ...
... requirements. There’s still an infinite number of them but there’s a simple organising principle. Because we’re interested in small electric and magnetic fields, which vary only over long distances, the most important terms will be those with the fewest powers of A and the fewest derivatives. Our go ...
The BEH Mechanism and its Scalar Boson by François Englert
... of the original symmetry is always a discontinuous event at the phase transition point, but the order parameters may set in continuously as a function of temperature. In the latter case the phase transition is second order. Symmetry breaking by a second order phase transition occurs in particular in ...
... of the original symmetry is always a discontinuous event at the phase transition point, but the order parameters may set in continuously as a function of temperature. In the latter case the phase transition is second order. Symmetry breaking by a second order phase transition occurs in particular in ...
Effective Field Theory, Past and Future
... was. But I am sure that many in this audience know more than I do about the applications of effective field theory to the strong interactions since 1979, so I will mention only some early applications to strong interactions and a few applications to other areas of physics. I will then describe how w ...
... was. But I am sure that many in this audience know more than I do about the applications of effective field theory to the strong interactions since 1979, so I will mention only some early applications to strong interactions and a few applications to other areas of physics. I will then describe how w ...
Educative Uncertainty: Heisenberg, Zizek and Hegel (1)
... However, this unknowability is protected from contingency by Kant through presuppositions that become the target of Hegel’s critique of Kant. In the Phenomenology of Spirit Hegel offers a very simple rejoinder here. Implicit in Kant is the presupposition that the thought of pure reason is the error ...
... However, this unknowability is protected from contingency by Kant through presuppositions that become the target of Hegel’s critique of Kant. In the Phenomenology of Spirit Hegel offers a very simple rejoinder here. Implicit in Kant is the presupposition that the thought of pure reason is the error ...
hep-th/9303127 PDF
... The purpose of these lectures is to present a short review of some recent developments of the lattice approach to the problem of the quantization of gravity. This approach goes back to the seminal paper by Regge (Regge (1961)), but many new and sometimes surprising results have been obtained during ...
... The purpose of these lectures is to present a short review of some recent developments of the lattice approach to the problem of the quantization of gravity. This approach goes back to the seminal paper by Regge (Regge (1961)), but many new and sometimes surprising results have been obtained during ...
Quantum Manipulation Using Light-Atom Interaction
... The obtainable spin squeezing improves with the quality of the resonator and the number of atoms. Fig. 4 shows the calculated spin squeezing for a typical atom number (N=2×104) and varying finesse of the resonator. Note that we obtain excellent agreement between the calculation [23] and the experime ...
... The obtainable spin squeezing improves with the quality of the resonator and the number of atoms. Fig. 4 shows the calculated spin squeezing for a typical atom number (N=2×104) and varying finesse of the resonator. Note that we obtain excellent agreement between the calculation [23] and the experime ...
Broken Symmetries
... [3] discovery of the theory of Special Relativity, also in 1905, in which Lorentz transformations also underlie mechanics. When quantum mechanics was discovered in the 1920s, it looked at first as if non-relativistic quantum mechanics would be enough to explain the spectrum of the hydrogen atom. The ...
... [3] discovery of the theory of Special Relativity, also in 1905, in which Lorentz transformations also underlie mechanics. When quantum mechanics was discovered in the 1920s, it looked at first as if non-relativistic quantum mechanics would be enough to explain the spectrum of the hydrogen atom. The ...
Quantum gravity
Quantum gravity (QG) is a field of theoretical physics that seeks to describe the force of gravity according to the principles of quantum mechanics.The current understanding of gravity is based on Albert Einstein's general theory of relativity, which is formulated within the framework of classical physics. On the other hand, the nongravitational forces are described within the framework of quantum mechanics, a radically different formalism for describing physical phenomena based on probability. The necessity of a quantum mechanical description of gravity follows from the fact that one cannot consistently couple a classical system to a quantum one.Although a quantum theory of gravity is needed in order to reconcile general relativity with the principles of quantum mechanics, difficulties arise when one attempts to apply the usual prescriptions of quantum field theory to the force of gravity. From a technical point of view, the problem is that the theory one gets in this way is not renormalizable and therefore cannot be used to make meaningful physical predictions. As a result, theorists have taken up more radical approaches to the problem of quantum gravity, the most popular approaches being string theory and loop quantum gravity. A recent development is the theory of causal fermion systems which gives quantum mechanics, general relativity, and quantum field theory as limiting cases.Strictly speaking, the aim of quantum gravity is only to describe the quantum behavior of the gravitational field and should not be confused with the objective of unifying all fundamental interactions into a single mathematical framework. While any substantial improvement into the present understanding of gravity would aid further work towards unification, study of quantum gravity is a field in it's own right with various branches having different approaches to unification. Although some quantum gravity theories, such as string theory, try to unify gravity with the other fundamental forces, others, such as loop quantum gravity, make no such attempt; instead, they make an effort to quantize the gravitational field while it is kept separate from the other forces. A theory of quantum gravity that is also a grand unification of all known interactions is sometimes referred to as a theory of everything (TOE).One of the difficulties of quantum gravity is that quantum gravitational effects are only expected to become apparent near the Planck scale, a scale far smaller in distance (equivalently, far larger in energy) than what is currently accessible at high energy particle accelerators. As a result, quantum gravity is a mainly theoretical enterprise, although there are speculations about how quantum gravity effects might be observed in existing experiments.