Dark Matters, Gravational Force, Neutron Life-Time Anomaly And
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Kaluza-Klein Gravity, Concentrating on the General Rel- Ativity, Rather Than Particle Physics Side of the Subject
Kaluza-Klein Gravity J. M. Overduin Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, British Columbia, Canada, V8W 3P6 and P. S. Wesson Department of Physics, University of Waterloo, Ontario, Canada N2L 3G1 and Gravity Probe-B, Hansen Physics Laboratories, Stanford University, Stanford, California, U.S.A. 94305 Abstract We review higher-dimensional unified theories from the general relativity, rather than the particle physics side. Three distinct approaches to the subject are identi- fied and contrasted: compactified, projective and noncompactified. We discuss the cosmological and astrophysical implications of extra dimensions, and conclude that none of the three approaches can be ruled out on observational grounds at the present time. arXiv:gr-qc/9805018v1 7 May 1998 Preprint submitted to Elsevier Preprint 3 February 2008 1 Introduction Kaluza’s [1] achievement was to show that five-dimensional general relativity contains both Einstein’s four-dimensional theory of gravity and Maxwell’s the- ory of electromagnetism. He however imposed a somewhat artificial restriction (the cylinder condition) on the coordinates, essentially barring the fifth one a priori from making a direct appearance in the laws of physics. Klein’s [2] con- tribution was to make this restriction less artificial by suggesting a plausible physical basis for it in compactification of the fifth dimension. This idea was enthusiastically received by unified-field theorists, and when the time came to include the strong and weak forces by extending Kaluza’s mechanism to higher dimensions, it was assumed that these too would be compact. This line of thinking has led through eleven-dimensional supergravity theories in the 1980s to the current favorite contenders for a possible “theory of everything,” ten-dimensional superstrings. -
Spontaneous Breaking of Conformal Invariance and Trace Anomaly
Spontaneous Breaking of Conformal Invariance and Trace Anomaly Matching ∗ A. Schwimmera and S. Theisenb a Department of Physics of Complex Systems, Weizmann Institute, Rehovot 76100, Israel b Max-Planck-Institut f¨ur Gravitationsphysik, Albert-Einstein-Institut, 14476 Golm, Germany Abstract We argue that when conformal symmetry is spontaneously broken the trace anomalies in the broken and unbroken phases are matched. This puts strong constraints on the various couplings of the dilaton. Using the uniqueness of the effective action for the Goldstone supermultiplet for broken = 1 supercon- formal symmetry the dilaton effective action is calculated. N arXiv:1011.0696v1 [hep-th] 2 Nov 2010 November 2010 ∗ Partially supported by GIF, the German-Israeli Foundation for Scientific Research, the Minerva Foundation, DIP, the German-Israeli Project Cooperation and the Einstein Center of Weizmann Institute. 1. Introduction The matching of chiral anomalies of the ultraviolet and infrared theories related by a massive flow plays an important role in understanding the dynamics of these theories. In particular using the anomaly matching the spontaneous breaking of chiral symmetry in QCD like theories was proven [1]. For supersymmetric gauge theories chiral anomaly matching provides constraints when different theories are related by “non abelian” duality in the infrared NS. The matching involves the equality of a finite number of parameters, “the anomaly coefficients” defined as the values of certain Green’s function at a very special singular point in phase space. The Green’s function themselves have very different structure at the two ends of the flow. The massive flows relate by definition conformal theories in the ultraviolet and infrared but the trace anomalies of the two theories are not matched: rather the flow has the property that the a-trace anomaly coefficient decreases along it [2]. -
Masse Des Neutrinos Et Physique Au-Delà Du Modèle Standard
œa UNIVERSITE PARIS-SUD XI THESE Spécialité: PHYSIQUE THÉORIQUE Présentée pour obtenir le grade de Docteur de l'Université Paris XI par Pierre Hosteins Sujet: Masse des Neutrinos et Physique au-delà du Modèle Standard Soutenue le 10 Septembre 2007 devant la commission d'examen: MM. Asmaa Abada, Sacha Davidson, Emilian Dudas, rapporteur, Ulrich Ellwanger, président, Belen Gavela, Thomas Hambye, rapporteur, Stéphane Lavignac, directeur de thèse. 2 Remerciements : Un travail de thèse est un travail de longue haleine, au cours duquel se produisent inévitablement beaucoup de rencontres, de collaborations, d'échanges... Voila pourquoi, sans doute, il me semble que la liste des personnes a qui je suis redevable est devenue aussi longue ! Tâchons cependant de remercier chacun comme il le mérite. En relisant ce manuscrit je ne peux m'empêcher de penser a Stéphane Lavignac, que je me dois de remercier pour avoir accepté d'encadrer mon travail de thèse et qui m'a toujours apporté le soutien et les explications nécessaires, avec une patience admirable. Sa grande rigueur d'analyse et sa minutie m'offrent un exemple que je m'évertuerai à suivre avec la plus grande application. Ces travaux n'auraient pas pu voir le jour non plus sans mes autres collaborateurs que sont Carlos Savoy, Julien Welzel, Micaela Oertel, Aldo Deandrea, Asmâa Abada et François-Xavier Josse-Michaux, qui ont toujours été disponibles et avec qui j'ai eu un plaisir certain a travailler. C'est avec gratitude que je remercie Asmâa pour tous les conseils et recommandations qu'elle n'a cessé de me fournir tout au long de mes études au sein de l'Université Paris XL Au cours de ces trois années de travail dans le domaine de la Physique Au-delà de Modèle Standard, j'ai bénéficié du contact de toute la communauté des théoriciens de la région. -
A Note on the Chiral Anomaly in the Ads/CFT Correspondence and 1/N 2 Correction
NEIP-99-012 hep-th/9907106 A Note on the Chiral Anomaly in the AdS/CFT Correspondence and 1=N 2 Correction Adel Bilal and Chong-Sun Chu Institute of Physics, University of Neuch^atel, CH-2000 Neuch^atel, Switzerland [email protected] [email protected] Abstract According to the AdS/CFT correspondence, the d =4, =4SU(N) SYM is dual to 5 N the Type IIB string theory compactified on AdS5 S . A mechanism was proposed previously that the chiral anomaly of the gauge theory× is accounted for to the leading order in N by the Chern-Simons action in the AdS5 SUGRA. In this paper, we consider the SUGRA string action at one loop and determine the quantum corrections to the Chern-Simons\ action. While gluon loops do not modify the coefficient of the Chern- Simons action, spinor loops shift the coefficient by an integer. We find that for finite N, the quantum corrections from the complete tower of Kaluza-Klein states reproduce exactly the desired shift N 2 N 2 1 of the Chern-Simons coefficient, suggesting that this coefficient does not receive→ corrections− from the other states of the string theory. We discuss why this is plausible. 1 Introduction According to the AdS/CFT correspondence [1, 2, 3, 4], the =4SU(N) supersymmetric 2 N gauge theory considered in the ‘t Hooft limit with λ gYMNfixed is dual to the IIB string 5 ≡ theory compactified on AdS5 S . The parameters of the two theories are identified as 2 4 × 4 gYM =gs, λ=(R=ls) and hence 1=N = gs(ls=R) . -
GRAND UNIFIED THEORIES Paul Langacker Department of Physics
GRAND UNIFIED THEORIES Paul Langacker Department of Physics, University of Pennsylvania Philadelphia, Pennsylvania, 19104-3859, U.S.A. I. Introduction One of the most exciting advances in particle physics in recent years has been the develcpment of grand unified theories l of the strong, weak, and electro magnetic interactions. In this talk I discuss the present status of these theo 2 ries and of thei.r observational and experimenta1 implications. In section 11,1 briefly review the standard Su c x SU x U model of the 3 2 l strong and electroweak interactions. Although phenomenologically successful, the standard model leaves many questions unanswered. Some of these questions are ad dressed by grand unified theories, which are defined and discussed in Section III. 2 The Georgi-Glashow SU mode1 is described, as are theories based on larger groups 5 such as SOlO' E , or S016. It is emphasized that there are many possible grand 6 unified theories and that it is an experimental problem not onlv to test the basic ideas but to discriminate between models. Therefore, the experimental implications are described in Section IV. The topics discussed include: (a) the predictions for coupling constants, such as 2 sin sw, and for the neutral current strength parameter p. A large class of models involving an Su c x SU x U invariant desert are extremely successful in these 3 2 l predictions, while grand unified theories incorporating a low energy left-right symmetric weak interaction subgroup are most likely ruled out. (b) Predictions for baryon number violating processes, such as proton decay or neutron-antineutnon 3 oscillations. -
Conformal Anomaly Actions for Dilaton Interactions
EPJ Web of Conferences 80, 00015 (2014) DOI: 10.1051/epj conf/20140001580 C Owned by the authors, published by EDP Sciences, 2014 Conformal anomaly actions for dilaton interactions Luigi Delle Rose1,a, Carlo Marzo1,b, Mirko Serino1,c 1Dipartimento di Matematica e Fisica "Ennio De Giorgi" Universitá del Salento and INFN Lecce Via per Arnesano 73100 Lecce, Italy Abstract. We discuss, in conformally invariant field theories such as QCD with massless fermions, a possible link between the perturbative signature of the conformal anomaly, in the form of anomaly poles of the 1-particle irreducible effective action, and its descrip- tion in terms of Wess-Zumino actions with a dilaton. The two descriptions are expected to capture the UV and IR behaviour of the conformal anomaly, in terms of fundamental and effective degrees of freedom respectively, with the dilaton effective state appearing in a nonlinear realization. As in the chiral case, conformal anomalies seem to be related to the appearance of these effective interactions in the 1PI action in all the gauge-invariant sectors of the Standard Model. We show that, as a consequence of the underlying anoma- lous symmetry, the infinite hierarchy of recurrence relations involving self-interactions of the dilaton is entirely determined only by the first four of them. This relation can be generalized to any even space-time dimension. 1 Introduction Conformal anomalies play a significant role in theories which are classically scale invariant, such as QCD. This type of anomaly manifests as a non-vanishing trace of the vacuum expectation value (vev) of the energy momentum tensor in a metric (gμν) and gauge field (Aμ) background. -
THE STANDARD MODEL and BEYOND: a Descriptive Account of Fundamental Particles and the Quest for the Unification of Their Interactions
THE STANDARD MODEL AND BEYOND: A descriptive account of fundamental particles and the quest for the uni¯cation of their interactions. Mesgun Sebhatu ([email protected]) ¤ Department of Chemistry, Physics and Geology Winthrop University, Rock Hill SC 29733 Abstract fundamental interactions|gravity, electroweak, and the strong nuclear|into one. This will be In the last three decades, signi¯cant progress has equivalent to having a complete theory of every- been made in the identi¯cation of fundamental thing (TOE). Currently, a contender for a TOE particles and the uni¯cation of their interactions. is the so called superstring theory. The theoret- This remarkable result is summarized by what ical extensions of the Standard Model and the is con¯dently called the Standard Model (SM). experimental tests of their predictions is likely This paper presents a descriptive account of the to engage high energy physicists of the 21st cen- Standard Model and its possible extensions. Ac- tury. cording to SM, all matter in the universe is made up of a dozen fermions|six quarks and six lep- tons. The quarks and leptons interact by ex- 1 HISTORICAL INTRO- changing a dozen gauge (spin|one) bosons| DUCTION eight gluons and four electroweak bosons. The Standard Model provides a framework for the Our job in physics is to see things sim- uni¯cation of the electroweak and strong nu- ply, to understand a great many com- clear forces. A major de¯ciency of the Standard plicated phenomena in a uni¯ed way, in Model is its exclusion of gravity. The ultimate terms of a few simple principles. -
The Beryllium Anomaly and New Physics
THE BERYLLIUM ANOMALY AND NEW PHYSICS New Physics at the Intensity Frontier CERN-EPFL-Korea Theory Institute Jonathan Feng, University of California, Irvine 21 February 2017 21 Feb 2017 Feng 1 OUTLINE A. J. Krasznhorkay et al., “Observation of Anomalous Internal Pair Creation in 8Be: A Possible Indication of a Light, Neutral Boson,” 1504.01527 [nucl-ex], PRL 116, 042501 (2016) J. Feng et al., “Protophobic Fifth Force Interpretation of the Observed Anomaly in 8Be Nuclear Transitions,” 1604.07411 [hep-ph], PRL 117, 071803 (2016) J. Feng et al., “Particle Physics Models for the 17 MeV Anomaly in Beryllium Nuclear Decays,” 1608.03591 [hep-ph], PRD 95, 035017 (2017) Jonathan Bart Iftah Susan Jordan Tim Flip Feng Fornal Galon Gardner Smolinsky Tait Tanedo 21 Feb 2017 Feng 2 NEW PHYSICS AT THE INTENSITY FRONTIER • There are currently many outstanding puzzles: neutrino masses, gauge hierarchy, strong CP, flavor, dark matter, baryogenesis, dark energy,... • Some of these motivate searches for new particles and forces at high energies: the energy frontier • But some also motivate searches for new physics that is light, but weakly coupled: the intensity frontier • Of particular interest here are connections to dark matter 21 Feb 2017 Feng 3 DARK MATTER AT THE INTENSITY FRONTIER !!! 21 Feb 2017 Feng 4 DARK SECTORS • All evidence for dark matter is gravitational. Perhaps it’s in a hidden sector, composed of particles with no SM gauge interactions (electromagnetic, weak, strong) Visible Dark Sector Sector • The dark sector may have a rich structure with matter and forces of its own Lee, Yang (1956); Kobsarev, Okun, Pomeranchuk (1966); Blinnikov, Khlopov (1982); Foot, Lew, Volkas (1991); Hodges (1993); Berezhiani, Dolgov, Mohapatra (1995); Pospelov, Ritz, Voloshin (2007); Feng, Kumar (2008);.. -
Anomalous Supersymmetry George Katsianis STAG Research Centre, Mathematical Sciences, University of Southampton
Anomalous Supersymmetry George Katsianis STAG Research Centre, Mathematical Sciences, University of Southampton 1. Symmetries 3. Anomalies 6. Results (for the experts) A symmetry of a physical system is any set of transformations that Sometimes classical symmetries fail to survive the quantization We consider the free massless Wess-Zumino model leave some properties of that system invariant. A simple example is procedure. This means that the original symmetries of the classical Z 1 S = d4x −∂ φ∗∂µφ − (ψγ¯ µ∂ ψ) that of the reflection symmetry of a picture, where the left and theory are not actual symmetries of the full quantum theory. We µ 2 µ right sides look like mirror images of each other. call this phenomenon a quantum anomaly. Since the discovery of the axial anomaly by Adler, Bell and Jackiw in 1969, the anomalies which is invariant under supersymmetry transformations of the form played a central role in theoretical physics. In some cases the δψ ∼ φ , δφ ∼ ψ existence of (gauge) anomalies lead to inconsistencies, so their and U(1) field transformations. The corresponding conserved cancellation help us build viable physical models. In other cases currents are the supercurrent Sµ and the R-current Rµ. (global) anomalies are linked to observable effects and explain We compute the 4-point correlation function of two supercurrents experimental data, since they allow classically forbidden processes and two R-currents T (Sµ(x )S¯ν(x )Rκ (x ) Rλ (x )i. to occur. One such example is the pion decay into two photons. 1 2 3 4 The Feynman diagrams for the connected part of this correlation function have the following form: Source: wild.maths.org 4. -
Ads/CFT Correspondence and Differential Geometry Johanna
. AdS/CFT Correspondence and Differential Geometry Johanna Erdmenger Max Planck–Institut fur¨ Physik, Munchen¨ 1 Outline 1. Introduction: The AdS/CFT correspondence 2. Conformal Anomaly 3. AdS/CFT for field theories with = 1 Supersymmetry N 4. Example: Sasaki-Einstein manifolds 2 AdS/CFT Correspondence (Maldacena 1997, AdS: Anti de Sitter space, CFT: conformal field theory) Witten; Gubser, Klebanov, Polyakov Duality Quantum Field Theory Gravity Theory ⇔ Arises from String Theory in a particular low-energy limit Duality: Quantum field theory at strong coupling Gravity theory at weak coupling ⇔ Conformal field theory in four dimensions Supergravity Theory on AdS S5 ⇔ 5 × 3 Anti-de Sitter space Anti de Sitter space: Einstein space with constant negative curvature has a boundary which is the upper half of the Einstein static universe (locally this may be conformally mapped to four-dimensional Minkowski space ) Isometry group of AdS5: SO(4, 2) AdS/CFT: relates conformal field theory at the boundary of AdS5 to gravity theory on AdS S5 5 × Isometry group of S5: SO(6) ( SU(4)) ∼ 4 AdS/CFT correspondence Anti-de Sitter space: Einstein space with constant negative curvature AdS space has a boundary 2 2r/L µ ν 2 Metric: ds = e ηµνdx dx + dr Isometry group of (d + 1)-dimensional AdS space coincides with conformal group in d dimensions (SO(d, 2)). AdS/CFT correspondence provides dictionary between field theory opera- tors and supergravity fields 2 φ , ∆ = d + d + L2m2 O∆ ↔ m 2 4 ! Items in the same dictionary entry have the same quantum numbers under superconformal symmetry SU(2, 2 4). -
Green-Schwarz Anomaly Cancellation
Green-Schwarz anomaly cancellation Paolo Di Vecchia Niels Bohr Instituttet, Copenhagen and Nordita, Stockholm Collège de France, 05.03.10 Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 1 / 30 Plan of the talk 1 Introduction 2 A quick look at the abelian axial anomaly 3 Few words on forms 4 Anomaly cancellation in type IIB superstring theory 5 Anomaly cancellation in type I superstring 6 Conclusions Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 2 / 30 Introduction I The theory of general relativity for gravity was formulated by Einstein in 1915. I It is a four-dimensional theory that extends the theory of special relativity. I While special relativity is invariant under the transformations of the Lorentz group, general relativity is invariant under an arbitrary change of coordinates. I In the twenties it was proposed by Theodor Kaluza and Oskar Klein to unify electromagnetism with gravity by starting from general relativity in a five-dimensional space-time and compactify the extra-dimension on a small circle. I In this way one obtains general relativity in four dimensions, a vector gauge field satisfying the Maxwell equations and a scalar. I This idea of extra dimensions was not pursued in the years after. I In the sixties and seventies, when I started to work in the physics of the elementary particles, everybody was strictly working in four dimensions. Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 3 / 30 I Also the dual resonance model, being a model for hadrons, was obviously formulated in four dimensions. -
Physics Beyond the Standard Model
SM Generalities Symmetries Electroweak Yukawa Methodology BSM Unification SU(5) SO(10) Flavour Conclusions Physics beyond the Standard Model Ulrich Nierste Karlsruhe Institute of Technology KIT Center Elementary Particle and Astroparticle Physics LHCb Workshop Neckarzimmern 13-15 February 2013 SM Generalities Symmetries Electroweak Yukawa Methodology BSM Unification SU(5) SO(10) Flavour Conclusions Scope The lecture gives an introduction to physics beyond the Standard Model associated with new particles in the 100 GeV– 10 TeV range. The concept is bottom-up, starting from the Standard Model and its problems, with emphasis on the standard way beyond the Standard Model: Grand unification (and supersymmetry). SM Generalities Symmetries Electroweak Yukawa Methodology BSM Unification SU(5) SO(10) Flavour Conclusions Scope The lecture gives an introduction to physics beyond the Standard Model associated with new particles in the 100 GeV– 10 TeV range. The concept is bottom-up, starting from the Standard Model and its problems, with emphasis on the standard way beyond the Standard Model: Grand unification (and supersymmetry). Not covered: Search strategies for new particles at colliders, theories of gravitation, large extra dimensions, strongly interacting Higgs sectors, ... SM Generalities Symmetries Electroweak Yukawa Methodology BSM Unification SU(5) SO(10) Flavour Conclusions Contents Standard Model Generalities Symmetries Electroweak interaction Yukawa interaction Methodology of new physics searches Beyond the Standard Model Towards unification of forces SU(5) SO(10) Probing new physics with flavour Conclusions SM Generalities Symmetries Electroweak Yukawa Methodology BSM Unification SU(5) SO(10) Flavour Conclusions The theorist’s toolbox A theory’s particles and their interactions are encoded in the Lagrangian .