DOCSLIB.ORG

THEORETICAL PHYSICS Scientific Activities Ii 1982

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
THEORETICAL PHYSICS Scientific Activities Ii 1982 IAEA-TECDOC-293 INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS Scientific Activities ii 1982 A TECHNICAL DOCUMENT ISSUEE TH Y DB INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1983 INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS: SCIENTIFIC ACTIVITIES IN 1982 IAEA, VIENNA, 1983 IAEA-TECDOC-293 Printe IAEe th AustriAn y i d b a August 1983 PLEAS AWARE EB E THAT MISSINE TH AL F LO G PAGE THIN SI S DOCUMENT WERE ORIGINALLY BLANK IAEe Th A doe t maintaisno n stock f reportso thin si s series. However, microfiche copie f thesso e reportobtainee b n sca d from INIS Clearinghouse International Atomic Energy Agency Wagramerstrasse5 0 10 P.Ox Bo . A-1400 Vienna, Austria Orders should be accompanied by prepayment of Austrian Schillings 60.00 in the form of a cheque or in the form of IAEA microfiche service coupons orderee whicb y hdma separatel ClearinghouseS I y N froI e mth . FOREWORD The poverty from which the developing countries suffer is not just material, it is intellectual also. And the first of these evils can never be eradicated unti e seconth l effectivels i d y relieved. a uniqu n I e attemp o fight t t intellectual deprivatio e Thirth n di n World, and to foster contact between physicists of all countries, the International Centr r Theoreticafo e l Physics (ICTP s establishewa ) n 156i d 4 e Internationaundeth e aegith rf o s l Atomic Energy Agency e CentrTh . e organizes research sessions, workshops, and extended courses on advanced topics in the physical and mathematical sciences and encourages scientists, especially froe developinth m g countries o visi t ,e ICTr extendeth fo tP d periods. It forms an international meeting point for scientists from all countrie d providean s s visitorsit s , principally those from developing countries, with facilities to conduct original research at the highest international standards of excellence. To extend the reach of its influence beyon e necessarilth d y limited numbe f visitoro r e Centrth sn entertaica e n i n s organizea yearha t i , n Associateshia d p procramm a networ d an ef Federate o k d Institutes which maintain extensive and fruitful links between the ICTP and the world's scientific community. Situated mainly in developing countries, there are over 70 Federated Institutes whose main proble s i scientifim c o isolatiocanwh y b ,d an n arrangement, send scientists to the Centre for between 40 and 120 man-days each year. The ICTP has 2^0 Associates, distinguished scientists living and working in developing countries, who can, t.nree times in six years, speno between six weeks and three months at the Centre, researching and discussing research in a creative environment that may not obtain in their own scientifically isolated institL.es e CentrTh s .alsi e o fostering young scientists from developing countries by appointing Junior Associates who gain acces o booksst , journals d scientifi,an c articles throug ICTPe th h . Thanks to the generosity of -the Italian Government, ana of the regional community, the Centre was established with its own premises in Miramare, just outside Trieste, Italy. The Italian Government also makes a substantial annual grant to the Centre. In 1970 UNESCO joined the IAEA in financing the Centre. Since 196e Centrth 4s welcomeha e 0 dscientist 00 ove- 14 r s fro5 11 m Member States of the IAEA and UNESCO. TABLE OF CONTENUS 7 REVIEA W PAR: I T Calenda2 1 Scientifif ro c Activities 1982 - Statistical summar Participatiof yo Researce th n d ni han 3 1 Traimng-for-Research Activities Tabl Participationf eo Geographiy ,"b c Area, numbe visf ro - itors and man/months 14 Tabl Participationn eo Long-tery ,b Short-terd man m activitie5 1 s 7 1 SCIENTIFIE TH C PAS : PROGRAMMTII E - Physic Energd san y - Winter Colleg Nuclean eo r Physic Reactorsd san : Par: tI Cours Advancen eo Nuclean si r Theor Nuclead yan r Datr afo Reactor Applications 17 - Part II: Course on Reactor Physics Aspects of Safety Analysis 18 - Topical Meetin0 2 Nuclean go r Fluid Dynamics Third Seminar in Solar Energy (in French) 22 Nuclear Physics Pre-Prints in 1982 23 - Physic Frontierd san Knowledgf so e Elementary Particle Physic Fundamentad san l Theory Researc4 2 h Summer Workshop in Particle Physics 25 - September School on Supergravity & Supersymmetry 27 Worksho Non-Perturbativn po 8 2 e Field D TheorQC d yan - HE Pre-Prints in 1982 29 - PhysicLivine th f gso State - Summer College in Biophysics 33 International Conferenc Applicationn eo Physicf so o st Medicine and Biology 34 - Physics and Technology Spring College on Amorphous Solids and the Liquid State 36 - Researc Condensen hi d Matter Physicd san Research Worksho Condensen pi 8 3 d Matter Physics - Working Party on the Mechanical Behaviour of Solids 40 2nd Trieste International Symposium on Statistical Mechanics 1 4 of Adsorption Trieste-IUPAd 2n - P Semiconductor Symposium "Surface sInter& - 2 4 faces: Physic Electronicsd san " Solid State Pre-Prints in 1982 44 - Applicable Mathematics and Planning Models - Summer Worksho7 4 Fibrn po e Bundle Geometrd san y Autum8 4 n Cours Mathematican eo l Ecology 0 5 - Math Pre-Print 198n si 2 - Physic Oceansf so « Atmosphere Doserte th d s,an - Autumn Course on Geomagnetism, the Ionosphere and Magneto- shpere 51 Activities Outside the Scheduled Programme - Miscellaneous Research 52 Miscellaneous Pre-Prints in 1982 53 - Hosted Activitie Co-sponsored san d Regional4 5 Activities - Regional Activities Organize Centre th y edb Colleg Theorn eo Condensef yo d Matte5 5 Accrar- , Ghana Workshop on Monsson Dynamics - Dacca, Bangladesh 56 Latin-Americat 1s - nInternationad Schoo3r d lan l Symposiun mo Non-Conventional Energy - Bogota,Colombia 57 PART I. THE CENTR ES ACHIEVEMENT' N I S A Review The main fields of research and training-for-research, divided into their programme components Internationae th t ,a l Centr Theoreticar fo e l Physics in 1^82 were: Physic Energd san y Nuclear physics; Solar energy Physics and Frontiers of Knowledge Elementary particles and fundamental theory; Physic livine th f sgo state Physic Technologd san y Condensed matter physics Applicable Mathematic Plannind san g Models Applicable mathematics; Mathematical ecology Physic Environmene th f Naturaf so o d tan l Resources Geomagnetism; Ionospheri magned can t ospheric physics; Atmospheric physics Physics and Development Physics and Energy Centre Th e maintaine higda h leve activitf o l thin i y s component yeae ,th r commencing with the Winter College on Nuclear Physics and Reactors. This activity divides wa d intpartso coursa firsotw e s th :Advancen twa eo Nuclean si r Theory d Nucleaan r Dat Reactor afo r Applications, held fro Januar5 2 m l'o yt y February attended an 2 scientistJ? y db fro1 7 sm- developing Member States e seconTh . d pardedicates twa Reactoo dt r Physics Aspect Safetf so y Analysi tood san k place from 22 February to 1^ March. Altogether ix4 scientists participated in this second phase of the Winter College; 73 of these represented developing countries. Both courses were organize closn di e collaboration witIAEAe hth topicaA . l meeting on Nuclear Fluid Dynamics took place from 11 to 15 October, bringing together 65 scientists working in this field. Other activities in the energy compon- ent included the III Séminaire su l'Energie Solaire (French Solar Energy course), which brought togethe French-speakin1 r7 g physicists, engineer techniciansd san ; collaboratio d contributionnan s receive variouy db s Ministrie d Commissionsan f so the French Government for the course are gratefully acknowledged. For the first time, the Centre, in collaboration with the Asociaciôn Centro Internacional de Flsic Bogotae ad , organize activitn d a fiel e th solaf do n yi r energa n yi developing region InternationaI II .e th Thi s swa l Symposiu Latin-Americad man n Schoo Non-Conventionan o l l Energy, whic hels Colombihn wa i d July0 3 ao .t fro 3 m1 The School attracte visitors9 d11 onlt ,no y from Sout d Centrahan l America frot ,bu m other far-distant developing countries as well. Physic Frontiera san Knowledgf so e The research group in elementary particle physics and fundamental theory paste th n ,i continuins a , is activits git y throughou yeare tth ; scientisto wh s participated in the research of the group during 1^/82 were 200; 106 of them were from developing countries activitiee Th . s stregthening project thin si s field were a summer workshop in Particle Physics, held from 21 June until 31 July and attended Toy 77 scientists, and the September School and Workshop on Supergravity and Super- symmetry, which took place from 6 to 18 September and attracted another 167 scientists. In mid-December a workshop on non-perturbative field theory and quantum gauge theor s helywa d wit participatioe hth ^,f no Q scientists. LivinPhysice th d gs an Stat e In the field of physics of the living state, as well, activity was high: 217 visitors attended the conference on Applications of Physics to Medicine and Biology held fro Marc0 April2 m3 o ht . Thi followes workshoe swa th y db p Europeae ofth n Molecular Biology Organization, dedicate Functionao dt l Inte- gration of Cell Surface and Cytoskeleton Control Systems, organized by the International Schoo Advancer lfo d Studies (SISSA hosteCentree d )th an y n db I . addition, from 2 to 27 August, a summer college in Biophysics was held, bringing together another 152 scientists, the majority (117) representing developing countries. Physio Technologd san y The permanent condensed matter physics research group carried out its activity throughout the year; and some 33 scientists, 28 of whom were from developing countries, researce joineth n di h project groupe th f .so Scheduled activit fiele th dn yi als o continued bienniae ,th l college being dedicated this yea Amorphouo rt s Solids Liquiane dth d State collegee Th .
Load more

Recommended publications
  • Arxiv:1911.13166V1 [Hep-Th] 29 Nov 2019
    Composite Gravitons from Metric-Independent Quantum Field Theories∗ Christopher D. Caroney High Energy Theory Group, Department of Physics, William & Mary, Williamsburg, VA 23187-8795 (Dated: December 2, 2019) Abstract We review some recent work by Carone, Erlich and Vaman on composite gravitons in metric- independent quantum field theories, with the aim of clarifying a number of basic issues. Focusing on a theory of scalar fields presented previously in the literature, we clarify the meaning of the tunings required to obtain a massless graviton. We argue that this formulation can be interpreted as the massless limit of a theory of massive composite gravitons in which the graviton mass term is not of Pauli-Fierz form. We then suggest closely related theories that can be defined without such a limiting procedure (and hence without worry about possible ghosts). Finally, we comment on the importance of finding a compelling ultraviolet completion for models of this type, and discuss some possibilities. arXiv:1911.13166v1 [hep-th] 29 Nov 2019 ∗ Invited Brief Review for Modern Physics Letters A. [email protected] 1 I. INTRODUCTION A quantum field may represent a fundamental degree of freedom, or a composite state described within the context of an effective theory that is applicable in a low-energy regime. The idea that the gauge fields of the standard model may not be fundamental has appeared periodically in the literature over the past 50 years [1{3]. Such models must have a gauge invariance even when no gauge fields are included ab initio. Of particular interest to us here are models like those described in Ref.
    [Show full text]
  • Einstein's Geometrical Versus Feynman's Quantum
    universe Review Einstein’s Geometrical versus Feynman’s Quantum-Field Approaches to Gravity Physics: Testing by Modern Multimessenger Astronomy Yurij Baryshev Astronomy Department, Mathematics & Mechanics Faculty, Saint Petersburg State University, 28 Universitetskiy Prospekt, 198504 St. Petersburg, Russia; [email protected] or [email protected] Received: 17 August 2020; Accepted: 7 November 2020; Published: 18 November 2020 Abstract: Modern multimessenger astronomy delivers unique opportunity for performing crucial observations that allow for testing the physics of the gravitational interaction. These tests include detection of gravitational waves by advanced LIGO-Virgo antennas, Event Horizon Telescope observations of central relativistic compact objects (RCO) in active galactic nuclei (AGN), X-ray spectroscopic observations of Fe Ka line in AGN, Galactic X-ray sources measurement of masses and radiuses of neutron stars, quark stars, and other RCO. A very important task of observational cosmology is to perform large surveys of galactic distances independent on cosmological redshifts for testing the nature of the Hubble law and peculiar velocities. Forthcoming multimessenger astronomy, while using such facilities as advanced LIGO-Virgo, Event Horizon Telescope (EHT), ALMA, WALLABY, JWST, EUCLID, and THESEUS, can elucidate the relation between Einstein’s geometrical and Feynman’s quantum-field approaches to gravity physics and deliver a new possibilities for unification of gravitation with other fundamental quantum physical interactions.
    [Show full text]
  • Soft Collinear Effective Theory for Gravity
    Soft collinear effective theory for gravity Takemichi Okui and Arash Yunesi Department of Physics, Florida State University, 77 Chieftain Way, Tallahassee, FL 32306, USA Abstract We present how to construct a Soft Collinear Effective Theory (SCET) for gravity at the leading and next-to-leading powers from the ground up. The soft graviton theorem and decou- pling of collinear gravitons at the leading power are manifest from the outset in the effective symmetries of the theory. At the next-to-leading power, certain simple structures of amplitudes, which are completely obscure in Feynman diagrams of the full theory, are also revealed, which greatly simplifies calculations. The effective lagrangian is highly constrained by effectively mul- tiple copies of diffeomorphism invariance that are inevitably present in gravity SCET due to mode separation, an essential ingredient of any SCET. Further explorations of effective theories of gravity with mode separation may shed light on lagrangian-level understandings of some of the surprising properties of gravitational scattering amplitudes. A gravity SCET with an ap- arXiv:1710.07685v3 [hep-th] 16 Feb 2018 propriate inclusion of Glauber modes may serve as a powerful tool for studying gravitational scattering in the Regge limit. Contents 1 Introduction 2 2 Building up gravity SCET 3 2.1 Fundamentals . .3 2.1.1 The target phase space . .3 2.1.2 Manifest power counting . .4 2.1.3 Other underlying assumptions . .5 2.2 The collinear lightcone coordinates . .5 2.3 Mode separation and scaling . .6 2.3.1 The collinear momentum scaling . .6 2.3.2 The cross-collinear scaling and reparametrization invariance (RPI) .
    [Show full text]
  • Composite Gravity from a Metric-Independent Theory of Fermions
    Composite gravity from a metric-independent theory of fermions Christopher D. Carone∗ and Joshua Erlichy High Energy Theory Group, Department of Physics, College of William and Mary, Williamsburg, VA 23187-8795 Diana Vamanz Department of Physics, University of Virginia, Box 400714, Charlottesville, VA 22904, USA (Dated: April 5, 2019) Abstract We present a metric-independent, diffeomorphism-invariant model with interacting fermions that contains a massless composite graviton in its spectrum. The model is motivated by the supersym- metric D-brane action, modulated by a fermion potential. The gravitational coupling is related to new physics at the cutoff scale that regularizes UV divergences. We also speculate on possible extensions of the model. ∗[email protected] [email protected] [email protected] 1 I. INTRODUCTION In Refs. [1, 2], we presented a generally covariant model of scalar fields in which gravity appears as an emergent phenomenon in the infrared. The theory requires a physical cutoff that regularizes ultraviolet divergences, and the Planck scale is then related to the cutoff scale. The existence of a massless graviton pole in a two-into-two scattering amplitude was demonstrated nonperturbatively by a resummation of diagrams, that was made possible by working in the limit of a large number of physical scalar fields φa, for a = 1 :::N. Although that work assumed a particular organizing principle, namely that the theory could be obtained from a different starting point where an auxiliary metric field is eliminated by imposing a constraint that the energy-momentum tensor of the theory vanishes, one could have just as easily started directly with the resulting non-polynomial action D v ! 2 −1 N D−1 ! Z D − 1 u D 2 u X a a X I J S = d x t det @µφ @νφ + @µX @νX ηIJ ; (1.1) V (φa) a=1 I;J=0 where D is the number of spacetime dimensions and V (φa) is the scalar potential.
    [Show full text]
  • Abstract a Natural Extension of Standard Warped Higher
    ABSTRACT Title of dissertation: A NATURAL EXTENSION OF STANDARD WARPED HIGHER-DIMENSIONAL COMPACTIFICATIONS: THEORY AND PHENOMENOLOGY Sungwoo Hong, Doctor of Philosophy, 2017 Dissertation directed by: Professor Kaustubh Agashe Department of Physics Warped higher-dimensional compactifications with \bulk" standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and par- tial compositeness, offer an elegant approach to resolving the electroweak hierar- chy problem as well as the origins of flavor structure. However, low-energy elec- troweak/flavor/CP constraints and the absence of non-standard physics at LHC Run 1 suggest that a \little hierarchy problem" remains, and that the new physics underlying naturalness may lie out of LHC reach. Assuming this to be the case, we show that there is a simple and natural extension of the minimal warped model in the Randall-Sundrum framework, in which matter, gauge and gravitational fields propagate modestly different degrees into the IR of the warped dimension, resulting in rich and striking consequences for the LHC (and beyond). The LHC-accessible part of the new physics is AdS/CFT dual to the mecha- nism of \vectorlike confinement", with TeV-scale Kaluza-Klein excitations of the gauge and gravitational fields dual to spin-0,1,2 composites. Unlike the mini- mal warped model, these low-lying excitations have predominantly flavor-blind and flavor/CP-safe interactions with the standard model. In addition, the usual leading decay modes of the lightest KK gauge bosons into top and Higgs bosons are sup- pressed. This effect permits erstwhile subdominant channels to become significant.
    [Show full text]
  • Arxiv:2101.09203V1 [Gr-Qc] 22 Jan 2021 a Powerful Selection Principle Can Be Implemented by Mation Behavior (Sec.III)
    Coordinate conditions and field equations for pure composite gravity Hans Christian Ottinger¨ ∗ ETH Z¨urich,Department of Materials, CH-8093 Z¨urich,Switzerland (Dated: January 25, 2021) Whenever an alternative theory of gravity is formulated in a background Minkowski space, the conditions characterizing admissible coordinate systems, in which the alternative theory of gravity may be applied, play an important role. We here propose Lorentz covariant coordinate condi- tions for the composite theory of pure gravity developed from the Yang-Mills theory based on the Lorentz group, thereby completing this previously proposed higher derivative theory of gravity. The physically relevant static isotropic solutions are determined by various methods, the high-precision predictions of general relativity are reproduced, and an exact black-hole solution with mildly singular behavior is found. I. INTRODUCTION As the composite theory of gravity [9], just like the underlying Yang-Mills theory, is formulated in a back- Only two years after the discovery of Yang-Mills theo- ground Minkowski space, the question arises how to char- ries [1], it has been recognized that that there is a strik- acterize the \good" coordinate systems in which the the- ing formal relationship between the Riemann curvature ory may be applied. This characterization should be tensor of general relativity and the field tensor of the Lorentz invariant, but not invariant under more general Yang-Mills theory based on the Lorentz group [2]. How- coordinate transformations, that is, it shares the formal ever, developing this particular Yang-Mills theory into a properties of coordinate conditions in general relativity. consistent and convincing theory of gravity is not at all However, the unique solutions obtained from Einstein's straightforward.
    [Show full text]
  • INTERNATIONAL CENTRE for THEORETICAL PHYSICS V
    •' ••'••'** \. IC/82/18U INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS v CCMPOSITE GRAVITY MD COMPOSITE SUPERGRAVITY Jerzy Lukierski INTERNATIONAL ATOMIC ENERGY AGENCY UNITED NATIONS EDUCATIONAL, SCIENTIFIC AND CULTURAL ORGANIZATION 1982MIRAMARE-TRIESTE IC/82/1&U International Atomic Energy Agency and United nations Educational Scientific and Cultural Organization INTERNATIOHAL CESTKE FOR THEORETICAL PHYSICS COMPOSITE GRAVITY. AHD COMPOSITE SUPERGHAVITY * Jeray Lukierski *• International Centre for Theoretical Physics, Trieste, Italy. - TRIESTE September 1982 • Talk given at XIth International Colloquium on Group-Theoretic Methods in Physics, Istanbul, Turkey, 23-28 August 1982. •* Permanent address: Institute for Theoretical Physics, University of Wroclaw, ul. Cybulskiego 36, Wroclav, Poland. The known examples of such a construction are the composite U(n) ( 3) 5 potentials obtained from lj(n" "^jn,) o-fields " >, sp(l) « SU{3) ABSTRACT composite gauge fields in HP(n) a-raodels °>'T\ or eo(8) gauge fields constructed from ^Trhrr o-fields describing scalar sector of N = 8 It is known that the composite YM K-t;aui;e theory can supergravity be constructed from a-flelds taking values in a sym- metric Riemannian space — . We extend such a frame- h 2. Such a scheme can be supersymmetrized in three ways . The first work to graded o-fields taking values in supercosets. already known way is obtained by supersymmetric extension of the space- We show that from supereoset a-fields one can con- time co-ordinates, i.e. by the replacement of o-fields by a-superfields. struct composite gravity, and from supercoset a- In such a formulation the composite gauge superfields are defined 1 superfields the composite- supergravity models.
    [Show full text]
  • Mathematical Structure and Physical Content of Composite Gravity in Weak-Field Approximation
    Research Collection Journal Article Mathematical structure and physical content of composite gravity in weak-field approximation Author(s): Öttinger, Hans Christian Publication Date: 2020-09-15 Permanent Link: https://doi.org/10.3929/ethz-b-000441983 Originally published in: Physical Review D 102(6), http://doi.org/10.1103/PhysRevD.102.064024 Rights / License: Creative Commons Attribution 4.0 International This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library PHYSICAL REVIEW D 102, 064024 (2020) Mathematical structure and physical content of composite gravity in weak-field approximation Hans Christian Öttinger * ETH Zürich, Department of Materials, CH-8093 Zürich, Switzerland (Received 29 May 2020; accepted 17 August 2020; published 9 September 2020) The natural constraints for the weak-field approximation to composite gravity, which is obtained by expressing the gauge vector fields of the Yang-Mills theory based on the Lorentz group in terms of tetrad variables and their derivatives, are analyzed in detail within a canonical Hamiltonian approach. Although this higher derivative theory involves a large number of fields, only a few degrees of freedom are left, which are recognized as selected stable solutions of the underlying Yang-Mills theory. The constraint structure suggests a consistent double coupling of matter to both Yang-Mills and tetrad fields, which results in a selection among the solutions of the Yang-Mills theory in the presence of properly chosen conserved currents. Scalar and tensorial coupling mechanisms are proposed, where the latter mechanism essentially reproduces linearized general relativity. In the weak-field approximation, geodesic particle motion in static isotropic gravitational fields is found for both coupling mechanisms.
    [Show full text]
  • Background-Independent Composite Gravity
    Background-Independent Composite Gravity Austin Batz,1, ∗ Joshua Erlich,1, y and Luke Mrini1, z 1High Energy Theory Group, Department of Physics, William & Mary, Williamsburg, VA 23187-8795, USA (Dated: November 12, 2020) Abstract We explore a background-independent theory of composite gravity. The vacuum expectation value of the composite metric satisfies Einstein's equations (with corrections) as a consistency condition, and selects the vacuum spacetime. A gravitational interaction then emerges in vacuum correlation functions. The action remains diffeomorphism invariant even as perturbation theory is organized about the dynamically selected vacuum spacetime. We discuss the role of nondynamical clock and rod fields in the analysis, the identification of physical observables, and the generalization to other theories including the standard model. arXiv:2011.06541v1 [gr-qc] 12 Nov 2020 ∗[email protected] [email protected] [email protected] 1 I. INTRODUCTION Diffeomorphism invariance is responsible for a number of conceptual and technical chal- lenges for quantum gravity. The Hamiltonian in diffeomorphism-invariant theories vanishes in the absence of a spacetime boundary, and is replaced by a constraint. In canonical quan- tum gravity [1], the functional Schr¨odingerequation is replaced by the Wheeler-DeWitt equation, which imposes the Hamiltonian constraint on states. The absence of an a priori notion of time evolution in such a description suggests a relational approach to dynamics in which a clock is identified from within the system under investigation [2]. The challenge of identifying a clock with which to describe dynamics in quantum gravity is the well-known problem of time [3]. Also related to diffeomorphism invariance is the puzzle of identifying observables.
    [Show full text]
  • Emergent Gravity from Hidden Sectors and TT Deformations
    Preprint typeset in JHEP style - HYPER VERSION CCTP-2020-11 ITCP-2020/11 DCPT-20/15 Emergent gravity from hidden sectors and TT deformations ♮ ♭,♮ ♭, P. Betzios , E. Kiritsis , V. Niarchos † ♮ APC, AstroParticule et Cosmologie, Universit´eParis Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cit´e, 10, rue Alice Domon et L´eonie Duquet, 75205 Paris Cedex 13, France. ♭ Crete Center for Theoretical Physics, Institute for Theoretical and Computational Physics, Department of Physics University of Crete, Heraklion, Greece † Department of Mathematical Sciences and Centre for Particle Theory, Durham University, Durham DH1 3LE, UK Abstract: We investigate emergent gravity extending the paradigm of the AdS/CFT correspondence. The emergent graviton is associated to the (dynamical) expectation value of the energy-momentum tensor. We derive the general effective description of such dynamics, and apply it to the case where a hidden theory gen- erates gravity that is coupled to the Standard Model. In the linearized description, generically, such gravity is massive with the presence of an extra scalar degree of arXiv:2010.04729v2 [hep-th] 3 Nov 2020 freedom. The propagators of both the spin-two and spin-zero modes are positive and well defined. The associated emergent gravitational theory is a bi-gravity theory, as is (secretly) the case in holography. The background metric on which the QFTs are defined, plays the role of dark energy and the emergent theory has always as a solution the original background metric. In the case where the hidden theory is holographic, the overall description yields a higher-dimensional bulk theory coupled to a brane.
    [Show full text]
  • Mathematical Structure and Physical Content of Composite Gravity in Weak-Field Approximation
    PHYSICAL REVIEW D 102, 064024 (2020) Mathematical structure and physical content of composite gravity in weak-field approximation Hans Christian Öttinger * ETH Zürich, Department of Materials, CH-8093 Zürich, Switzerland (Received 29 May 2020; accepted 17 August 2020; published 9 September 2020) The natural constraints for the weak-field approximation to composite gravity, which is obtained by expressing the gauge vector fields of the Yang-Mills theory based on the Lorentz group in terms of tetrad variables and their derivatives, are analyzed in detail within a canonical Hamiltonian approach. Although this higher derivative theory involves a large number of fields, only a few degrees of freedom are left, which are recognized as selected stable solutions of the underlying Yang-Mills theory. The constraint structure suggests a consistent double coupling of matter to both Yang-Mills and tetrad fields, which results in a selection among the solutions of the Yang-Mills theory in the presence of properly chosen conserved currents. Scalar and tensorial coupling mechanisms are proposed, where the latter mechanism essentially reproduces linearized general relativity. In the weak-field approximation, geodesic particle motion in static isotropic gravitational fields is found for both coupling mechanisms. An important issue is the proper Lorentz covariant criterion for choosing a background Minkowski system for the composite theory of gravity. DOI: 10.1103/PhysRevD.102.064024 I. INTRODUCTION composition rule expresses the corresponding gauge vector fields in terms of the tetrad or vierbein variables providing Einstein’s general theory of relativity may not be the a Cholesky-type decomposition of a metric. As a conse- final word on gravity.
    [Show full text]
  • The Fundamental Process of Energy a Qualitative Unification of Energy, Mass, and Gravity
    The Fundamental Process of Energy A Qualitative Unification of Energy, Mass, and Gravity Conrad Ranzan 2013 www.CellularUniverse.org Reprint of the article published in two parts in Infinite Energy Magazine issue #113 (Jan/Feb 2014) and issue #114 (Mar/Apr 2014) (www.infinite-energy.com) [I]f the ultimate model of physics is to be as simple as possible, then one should expect that all the features of our universe must at some level emerge purely from properties of space. –Stephen Wolfram, A New Kind of Science 1 [T]here must be, at the bottom of it all, not an equation, but an utterly simple idea. –John A. Wheeler Abstract: The Universe is built upon a two-faceted Primary-Cause process, which serves as the key to the fundamental process of energy. Positive and negative energy processes are defined and used to resolve the cause-of-mass question, the cause-of-gravitation mystery, the dark matter problem, the vacuum energy confusion, the energy-balance misunderstanding, and the source-energy enigma. “The Fundamental Process of Energy” presents a qualitative understanding and conceptual unification of energy, mass, and gravity. Keywords: energy; energy process; positive energy; negative energy; radiation; mass; gravitation; vacuum energy; dark energy; dark matter; source energy; cosmology; DSSU theory. Grasp the significance of the key process, understand In the ninth year following the discovery of its universality, and your view of energy will never be the A the DSSU another piece of the cosmic puzzle fell into same. place —the challenge of conceptual unification of energy was resolved. As a scientific term, energy is defined simply as the 1.
    [Show full text]