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The Niels Bohr Institute Dynamical Electroweak Breaking @ LHC Francesco Sannino MC-Workshop Frascati - 2006 Low Energy Effective Theory SM ….is not so standard • Origin of Mass of weak gauge bosons, quarks and leptons is unknown. • Strong Interactions are not fully understood/explored. • Unnaturally small Neutron Electric Dipole Moment Strong CP problem: New Challenges from Cosmology. • Dark Energy/Matter Focus on two..and aspects of the SM Beyond New as Origin of Mass for the weak gauge bosons, quarks … Understanding Strong Dynamics Let there be Mass Electroweak Precision Measurements We can already test New Physics! Kennedy,Lynn, Peskin-Takeuchi, Altarelli-Barbieri, Bertolini-Sirlin, Marciano-Rosner,..: Present Data mH=150 GeV hep-ex/0509008 Now: Dutta, Hagiwara and Yan ph/0603038.Weaken constraints S = 0.07±0.10 The Higgs Mechanism in Nature Superconductivity Macroscopic-Screening Non-Relativistic SM-Screening Relativistic Meissner-Mass Static Vector Potential Hidden structure Weak-GB-Mass ???? Elementary Higgs: Trivial and Non-natural Natural Scalars Exact Super Symmetry: Fermions ↔ Bosons Fermion’s custodial symmetry protects the Bosons Observe: susy partners Composite Scalar: Recall Superconductivity Substructure resolved at scale ΛS Observe: New Bound States Quasi Goldstone Boson: Protected by spontaneously broken global symmetries. Near Continuous Quantum Phase Transition Zero-temperature Bose – Einstein Condensation Lorentz symmetry is broken. Chiral Phase Transition at zero temperature. Lorentz symmetry is intact. Electroweak Symmetry Breaking @ LHC Electroweak Symmetry Breaking Technicolor SUSY Extra Dim. Curved Flat Technicolor New Strong Interactions at ~ 250 GeV [Weinberg, Susskind] Natural to use QCD-like dynamics. Problems with the Old Models • S-parameter: too large • Large Flavor Changing Neutral Currents (FCNC) • Limited knowledge of strong dynamics! Fermion masses versus FCNC SM-Fermion Masses PNG Masses ETC FCNC Operators should be sufficiently larger than TC 250GeV to reduce FCNC. Progress: Appelquist, Christensen, Piai, Shrok Near Conformal Properties α α non-conformal near-conformal ΛETC = 100-1000 ΛTC ΛTC ΛTC q ΛETC q β Holdom Appelquist Miransky, Yamawaki Cohen and Georgi… αc α* α Why the walking can help ? QCD-Like ~ Near the conformal window ~ Critical Number of techniflavors For fermions in the fundamental representation near conformal means: The number of techndoublets is Still too large S-parameter The S-parameter for fermions in the fundamental is Appelquist - Sannino Near conformal for N=2 means Nf/2=4 which yields: Experimentally S = 0.07±0.10 The New Model Near conformal for, Nf 2 Small FCNC + Top mass OK with precision data. Light Composite Higgs Dark Matter Sannino-Tuominen, hep-ph/0405209 Hong, Hsu, Sannino, hep-ph/0406200 Dietrich, Sannino and Tuominen, hep-ph/0505059, hep-ph/0510217 Evans-Sannino, hep-ph/0512080 Gudnason, Kouvaris and Sannino, hep-ph/0603014 The Model: The generalized S-Theory Inspired by progress in Strong Interactions `t Hooft - Large N Ryttov and F.S. `05 Corrigan and Ramond `79 Larks Kiritsis and Papavassiliou `90. Helpful for MC ??? Relation with Super Yang-Mills S-type A-type Armoni-Shifman-Veneziano SYM A-type: QCD vacuum properties, spectrum and confinement/chiral symmetry, finite temperature and density. Armoni-Shifman-Veneziano, Sannino-Shifman, Sannino, (Finite Temperature. Chiral Symmetry vs Confinement) Frandsen-Kouvaris-Sannino (Finite matter density) Sannino-Schechter (..in progress) N=1 Supersymmetric-Spectrum Merlatti-Sannino Feo-Merlatti-Sannino S-type: Composite Higgs from Higher Representations Sannino Not ruled out, LCH and DM Dietrich-Tuominen-Sannino, Hong-Hsu-Sannino, Sannino-Tuominen Evans-Sannino Gudnason, Kouvaris and Sannino Phase Diagram for the S-Theory Phase diagram as function of Nf and N. [Sannino-Tuominen] For N=2,3,4,5 we have that Nf= 2 Nf=2 & N=2: Minimal-Walking-Theory Universal critical number of flavors in the adjoint: Nfc=2.075 S-parameter • δ ~ 0.013 due to near conformal dynamics [Sundrum-Hsu, Appelquist-Sannino]. • The estimate for S in the S-type model is: Model versus EWPData 150 GeV 68% contour 4th Lepton Family Electron (m2) and Neutrino (m1) Dirac masses. Standard Hypercharge Assignment A natural LCH* • Via trace anomaly and the behavior of the underlying beta function near the chiral/conformal phase transition we show: Phenomenology of a LCH Associate Higgs production Zerwekh 05 Spectrum Techni-Mesons Techni-Baryons Electric Charge An Effective Theory Some Scenarios Dark Side of the 5th Force Nussinov Barr, Chivukula and Farhi Technibaryon, DD Universe Charge Neutrality. Chemical Equilibrium Taking care of the Sphaleron Processes Gudnason, Kouvaris, F.S. ph -0603014 Predictions and Outlook • MH ~ light • Fourth Family of Leptons around the Z mass. • 6 light scalars will be observed. • Electroweak baryongenesis. Possible Strongly First order phase transition. • Lattice Simulations are possible • DM candidate-component • Unification, Holography…. LHC SUSY TC ED Spectrum and Effective Theory I Spectrum and Effective Theory II Naturality Small parameters stay small under radiative corrections. The electron Mass If set to zero the U(1)L× U(1)R forbids its regeneration Naturalness begs an explanation of the origin of mass. No conflict with any small value of the electron mass Is the Higgs Natural? No custodial symmetry protecting a scalar mass. A mass appears even if ab initio is set to zero! Hierarchy between the EW scale and the Planck Scale. No!