What Is String Theory?
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M Theory As a Holographic Field Theory
hep-th/9712130 CALT-68-2152 M-Theory as a Holographic Field Theory Petr Hoˇrava California Institute of Technology, Pasadena, CA 91125, USA [email protected] We suggest that M-theory could be non-perturbatively equivalent to a local quantum field theory. More precisely, we present a “renormalizable” gauge theory in eleven dimensions, and show that it exhibits various properties expected of quantum M-theory, most no- tably the holographic principle of ’t Hooft and Susskind. The theory also satisfies Mach’s principle: A macroscopically large space-time (and the inertia of low-energy excitations) is generated by a large number of “partons” in the microscopic theory. We argue that at low energies in large eleven dimensions, the theory should be effectively described by arXiv:hep-th/9712130 v2 10 Nov 1998 eleven-dimensional supergravity. This effective description breaks down at much lower energies than naively expected, precisely when the system saturates the Bekenstein bound on energy density. We show that the number of partons scales like the area of the surface surrounding the system, and discuss how this holographic reduction of degrees of freedom affects the cosmological constant problem. We propose the holographic field theory as a candidate for a covariant, non-perturbative formulation of quantum M-theory. December 1997 1. Introduction M-theory has emerged from our understanding of non-perturbative string dynamics, as a hypothetical quantum theory which has eleven-dimensional supergravity [1] as its low- energy limit, and is related to string theory via various dualities [2-4] (for an introduction and references, see e.g. -
Census Taking
Current Logic of String Theory • Pick an asymptotically cold background. • Calculate the low energy S-matrix (or boundary correlators). • Find a semiclassical action that gives the same amplitudes. • Use the semiclassical action (perhaps non-perturbatively) to construct low energy bulk physics. Background Independence? Bundling different asymptotically cold backgrounds into a single quantum system (Hilbert Space) does not appear to make sense. This is a BIG problem: Real cosmology is NOT asymptotically cold. De Sitter space is asymptotically warm. Finite Hilbert space for every diamond. Banks, Fischler Quantum description ????????????????? Do we have a set of principles that we can rely on? No. Do we need them? Yes. Do we have a set of principles that we can rely on? No. Do we need them? Yes. The measure problem Solve equations of motion in freely falling frame and express A in terms of operators in the remote past. † Ain = U A U Ain Using the S-matrix we can run the operator to the remote future † Aout = S Ain S = (S U†) Ain (U S†) Aout is an operator in the outgoing space of states that has the same statistics as the behind-the-horizon operator A. That is the meaning of Black Hole Complementarity: Conjugation by (S U†). Transition to a “Hat” (supersymmetric bubble with Λ=0) Asymptotically cold at T Æ∞ but not as R Æ∞ Hat Complementarity? The CT’s backward light cone intersects each space- like hypersurface. The hypersurfaces are uniformly negatively curved spaces. Space-like hypersurface intersects the CT’s backward light-cone. In the limit tCT Æ∞ the CT’s Hilbert space becomes infinite. -
WILLY FISCHLER Born: May 30, 1949 Antwerp, Belgium Education
WILLY FISCHLER Born: May 30, 1949 Antwerp, Belgium Education: Universite Libre de Bruxelles Licence in Physics with \grande distinction", 1972 (Equivalent to the American Masters degree). Universite Libre de Bruxelles Ph.D., 1976 with \la plus grande distinction". Austin Community College Emergency Medical Services Professions EMT Paramedic Certificate, 2009. Nationally Certified Paramedic, 2009- Texas Department of State Health Services Licensed EMT-P, 2009- Present Position: University of Texas at Austin Jane and Roland Blumberg Centennial Professor in Physics 2000- Professor of Physics 1983-2000 Associate Director Theory Group 2003- Marble Falls Area EMS Licensed Paramedic 2009- Past Positions: CERN Geneva 1975-77 Postdoctoral Fellow Los Alamos Scientific Lab, 1977-1979 Postdoctoral Fellow University of Pennsylvania, 1979-1983 Assistant Professor Institute for Advanced Study, Princeton Official Visitor, September 1980 - May 1981 1 On leave - Belgian Army, June 1981 - May 1982 Awards: CERN Fellowship 1975-77 1979-1980 Recipient of Outstanding Junior Researcher Award, DOE 1987-88 Fellow to the Jane and Roland Blumberg Centennial Professorship in Physics Dean's Fellow, Fall 1997 2000{ Jane and Roland Blumberg Centennial Professor in Physics Volunteer: Children's Hospital PACU, 2005-7 Westlake Fire Department, EMT 2006- PUBLICATIONS 1. Gauge invariance in spontaneously broken symmetries: (with R. Brout) Phys. Rev. D11, 905 (1975). 2. Effective potential instabilities and bound-state formation: (with E. Gunzig, and R. Brout) Il Nuovo Cimento 29A, 504 (1975); 3. Effective potential, instabilities and bound state formation: (Adden- dum) (with E. Gunzig, and R. Brout) Il Nuovo Cimento 32A, 125 (1976). 4. Magnetic confinement in non-Abelian gauge field theory: (with F. -
2018 APS Prize and Award Recipients
APS Announces 2018 Prize and Award Recipients The APS would like to congratulate the recipients of these APS prizes and awards. They will be presented during APS award ceremonies throughout the year. Both March and April meeting award ceremonies are open to all APS members and their guests. At the March Meeting, the APS Prizes and Awards Ceremony will be held Monday, March 5, 5:45 - 6:45 p.m. at the Los Angeles Convention Center (LACC) in Los Angeles, CA. At the April Meeting, the APS Prizes and Awards Ceremony will be held Sunday, April 15, 5:30 - 6:30 p.m. at the Greater Columbus Convention Center in Columbus, OH. In addition to the award ceremonies, most prize and award recipients will give invited talks during the meeting. Some recipients of prizes, awards are recognized at APS unit meetings. For the schedule of APS meetings, please visit http://www.aps.org/meetings/calendar.cfm. Nominations are open for most 2019 prizes and awards. We encourage members to nominate their highly-qualified peers, and to consider broadening the diversity and depth of the nomination pool from which honorees are selected. For nomination submission instructions, please visit the APS web site (http://www.aps.org/programs/honors/index.cfm). Prizes 2018 APS MEDAL FOR EXCELLENCE IN PHYSICS 2018 PRIZE FOR A FACULTY MEMBER FOR RESEARCH IN AN UNDERGRADUATE INSTITUTION Eugene N. Parker University of Chicago Warren F. Rogers In recognition of many fundamental contributions to space physics, Indiana Wesleyan University plasma physics, solar physics and astrophysics for over 60 years. -
Black Hole Production and Graviton Emission in Models with Large Extra Dimensions
Black hole production and graviton emission in models with large extra dimensions Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften vorgelegt beim Fachbereich Physik der Johann Wolfgang Goethe–Universit¨at in Frankfurt am Main von Benjamin Koch aus N¨ordlingen Frankfurt am Main 2007 (D 30) vom Fachbereich Physik der Johann Wolfgang Goethe–Universit¨at als Dissertation angenommen Dekan ........................................ Gutachter ........................................ Datum der Disputation ................................ ........ Zusammenfassung In dieser Arbeit wird die m¨ogliche Produktion von mikroskopisch kleinen Schwarzen L¨ochern und die Emission von Gravitationsstrahlung in Modellen mit großen Extra-Dimensionen untersucht. Zun¨achst werden der theoretisch-physikalische Hintergrund und die speziel- len Modelle des behandelten Themas skizziert. Anschließend wird auf die durchgefuhrten¨ Untersuchungen zur Erzeugung und zum Zerfall mikrosko- pisch kleiner Schwarzer L¨ocher in modernen Beschleunigerexperimenten ein- gegangen und die wichtigsten Ergebnisse zusammengefasst. Im Anschluss daran wird die Produktion von Gravitationsstrahlung durch Teilchenkollisio- nen diskutiert. Die daraus resultierenden analytischen Ergebnisse werden auf hochenergetische kosmische Strahlung angewandt. Die Suche nach einer einheitlichen Theorie der Naturkr¨afte Eines der großen Ziele der theoretischen Physik seit Einstein ist es, eine einheitliche und m¨oglichst einfache Theorie zu entwickeln, die alle bekannten Naturkr¨afte beschreibt. -
TASI Lectures on Emergence of Supersymmetry, Gauge Theory And
TASI Lectures on Emergence of Supersymmetry, Gauge Theory and String in Condensed Matter Systems Sung-Sik Lee1,2 1Department of Physics & Astronomy, McMaster University, 1280 Main St. W., Hamilton ON L8S4M1, Canada 2Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo ON N2L2Y5, Canada Abstract The lecture note consists of four parts. In the first part, we review a 2+1 dimen- sional lattice model which realizes emergent supersymmetry at a quantum critical point. The second part is devoted to a phenomenon called fractionalization where gauge boson and fractionalized particles emerge as low energy excitations as a result of strong interactions between gauge neutral particles. In the third part, we discuss about stability and low energy effective theory of a critical spin liquid state where stringy excitations emerge in a large N limit. In the last part, we discuss about an attempt to come up with a prescription to derive holographic theory for general quantum field theory. arXiv:1009.5127v2 [hep-th] 16 Dec 2010 Contents 1 Introduction 1 2 Emergent supersymmetry 2 2.1 Emergence of (bosonic) space-time symmetry . .... 3 2.2 Emergentsupersymmetry . .. .. 4 2.2.1 Model ................................... 5 2.2.2 RGflow .................................. 7 3 Emergent gauge theory 10 3.1 Model ....................................... 10 3.2 Slave-particletheory ............................... 10 3.3 Worldlinepicture................................. 12 4 Critical spin liquid with Fermi surface 14 4.1 Fromspinmodeltogaugetheory . 14 4.1.1 Slave-particle approach to spin-liquid states . 14 4.1.2 Stability of deconfinement phase in the presence of Fermi surface... 16 4.2 Lowenergyeffectivetheory . .. .. 17 4.2.1 Failure of a perturbative 1/N expansion ............... -
Round Table Talk: Conversation with Nathan Seiberg
Round Table Talk: Conversation with Nathan Seiberg Nathan Seiberg Professor, the School of Natural Sciences, The Institute for Advanced Study Hirosi Ooguri Kavli IPMU Principal Investigator Yuji Tachikawa Kavli IPMU Professor Ooguri: Over the past few decades, there have been remarkable developments in quantum eld theory and string theory, and you have made signicant contributions to them. There are many ideas and techniques that have been named Hirosi Ooguri Nathan Seiberg Yuji Tachikawa after you, such as the Seiberg duality in 4d N=1 theories, the two of you, the Director, the rest of about supersymmetry. You started Seiberg-Witten solutions to 4d N=2 the faculty and postdocs, and the to work on supersymmetry almost theories, the Seiberg-Witten map administrative staff have gone out immediately or maybe a year after of noncommutative gauge theories, of their way to help me and to make you went to the Institute, is that right? the Seiberg bound in the Liouville the visit successful and productive – Seiberg: Almost immediately. I theory, the Moore-Seiberg equations it is quite amazing. I don’t remember remember studying supersymmetry in conformal eld theory, the Afeck- being treated like this, so I’m very during the 1982/83 Christmas break. Dine-Seiberg superpotential, the thankful and embarrassed. Ooguri: So, you changed the direction Intriligator-Seiberg-Shih metastable Ooguri: Thank you for your kind of your research completely after supersymmetry breaking, and many words. arriving the Institute. I understand more. Each one of them has marked You received your Ph.D. at the that, at the Weizmann, you were important steps in our progress. -
An Introduction to Effective Field Theory
An Introduction to Effective Field Theory Thinking Effectively About Hierarchies of Scale c C.P. BURGESS i Preface It is an everyday fact of life that Nature comes to us with a variety of scales: from quarks, nuclei and atoms through planets, stars and galaxies up to the overall Universal large-scale structure. Science progresses because we can understand each of these on its own terms, and need not understand all scales at once. This is possible because of a basic fact of Nature: most of the details of small distance physics are irrelevant for the description of longer-distance phenomena. Our description of Nature’s laws use quantum field theories, which share this property that short distances mostly decouple from larger ones. E↵ective Field Theories (EFTs) are the tools developed over the years to show why it does. These tools have immense practical value: knowing which scales are important and why the rest decouple allows hierarchies of scale to be used to simplify the description of many systems. This book provides an introduction to these tools, and to emphasize their great generality illustrates them using applications from many parts of physics: relativistic and nonrelativistic; few- body and many-body. The book is broadly appropriate for an introductory graduate course, though some topics could be done in an upper-level course for advanced undergraduates. It should interest physicists interested in learning these techniques for practical purposes as well as those who enjoy the beauty of the unified picture of physics that emerges. It is to emphasize this unity that a broad selection of applications is examined, although this also means no one topic is explored in as much depth as it deserves. -
Soft Gravitons and the Flat Space Limit of Anti-Desitter Space
RUNHETC-2016-15, UTTG-18-16 Soft Gravitons and the Flat Space Limit of Anti-deSitter Space Tom Banks Department of Physics and NHETC Rutgers University, Piscataway, NJ 08854 E-mail: [email protected] Willy Fischler Department of Physics and Texas Cosmology Center University of Texas, Austin, TX 78712 E-mail: fi[email protected] Abstract We argue that flat space amplitudes for the process 2 n gravitons at center of mass → energies √s much less than the Planck scale, will coincide approximately with amplitudes calculated from correlators of a boundary CFT for AdS space of radius R LP , only ≫ when n < R/LP . For larger values of n in AdS space, insisting that all the incoming energy enters “the arena”[20] , implies the production of black holes, whereas there is no black hole production in the flat space amplitudes. We also argue, from unitarity, that flat space amplitudes for all n are necessary to reconstruct the complicated singularity arXiv:1611.05906v3 [hep-th] 8 Apr 2017 at zero momentum in the 2 2 amplitude, which can therefore not be reproduced as → the limit of an AdS calculation. Applying similar reasoning to amplitudes for real black hole production in flat space, we argue that unitarity of the flat space S-matrix cannot be assessed or inferred from properties of CFT correlators. 1 Introduction The study of the flat space limit of correlation functions in AdS/CFT was initiated by the work of Polchinski and Susskind[20] and continued in a host of other papers. Most of those papers agree with the contention, that the limit of Witten diagrams for CFT correlators smeared with appropriate test functions, for operators carrying vanishing angular momentum on the compact 1 space,1 converge to flat space S-matrix elements between states in Fock space. -
SUSY, Landscape and the Higgs
SUSY, Landscape and the Higgs Michael Dine Department of Physics University of California, Santa Cruz Workshop: Nature Guiding Theory, Fermilab 2014 Michael Dine SUSY, Landscape and the Higgs A tension between naturalness and simplicity There have been lots of good arguments to expect that some dramatic new phenomena should appear at the TeV scale to account for electroweak symmetry breaking. But given the exquisite successes of the Model, the simplest possibility has always been the appearance of a single Higgs particle, with a mass not much above the LEP exclusions. In Quantum Field Theory, simple has a precise meaning: a single Higgs doublet is the minimal set of additional (previously unobserved) degrees of freedom which can account for the elementary particle masses. Michael Dine SUSY, Landscape and the Higgs Higgs Discovery; LHC Exclusions So far, simplicity appears to be winning. Single light higgs, with couplings which seem consistent with the minimal Standard Model. Exclusion of a variety of new phenomena; supersymmetry ruled out into the TeV range over much of the parameter space. Tunings at the part in 100 1000 level. − Most other ideas (technicolor, composite Higgs,...) in comparable or more severe trouble. At least an elementary Higgs is an expectation of supersymmetry. But in MSSM, requires a large mass for stops. Michael Dine SUSY, Landscape and the Higgs Top quark/squark loop corrections to observed physical Higgs mass (A 0; tan β > 20) ≈ In MSSM, without additional degrees of freedom: 126 L 124 GeV H h m 122 120 4000 6000 8000 10 000 12 000 14 000 HMSUSYGeVL Michael Dine SUSY, Landscape and the Higgs 6y 2 δm2 = t m~ 2 log(Λ2=m2 ) H −16π2 t susy So if 8 TeV, correction to Higgs mass-squred parameter in effective action easily 1000 times the observed Higgs mass-squared. -
Collective Coordinates for D-Branes 1 Introduction
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server UTTG-01-96 Collective Co ordinates for D-branes Willy Fischler, Sonia Paban and Moshe Rozali Theory Group, Department of Physics University of Texas, Austin, Texas 78712 Abstract We develop a formalism for the scattering o D-branes that includes collective co- ordinates. This allows a systematic expansion in the string coupling constant for such pro cesses, including a worldsheet calculation for the D-brane's mass. 1 Intro duction In the recent developments of string theory, solitons play a central role. For example, in the case of duality among various string theories, solitons of a weakly coupled string theory b ecome elementary excitations of the dual theory [1]. Another example, among many others, is the role of solitons in resolving singularities in compacti ed geometries, as they b ecome light[2]. In order to gain more insight in the various asp ects of these recent developments, it is imp ortant to understand the dynamics of solitons in the context of string theory.In this quest one of the to ols at our disp osal is the use of scattering involving these solitons. This includes the scattering of elementary string states o these solitons as well as the scattering among solitons. An imp ortant class of solitons that have emerged are D-branes [4]. In an in uential pap er [3]itwas shown that these D-branes carry R R charges, and are therefore a central ingredient in the aforementioned dualities. -
King's Research Portal
King’s Research Portal DOI: 10.1088/1742-6596/631/1/012089 Document Version Publisher's PDF, also known as Version of record Link to publication record in King's Research Portal Citation for published version (APA): Sarkar, S. (2015). String theory backgrounds with torsion in the presence of fermions and implications for leptogenesis. Journal of Physics: Conference Series, 631(1), [012089]. 10.1088/1742-6596/631/1/012089 Citing this paper Please note that where the full-text provided on King's Research Portal is the Author Accepted Manuscript or Post-Print version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version for pagination, volume/issue, and date of publication details. And where the final published version is provided on the Research Portal, if citing you are again advised to check the publisher's website for any subsequent corrections. General rights Copyright and moral rights for the publications made accessible in the Research Portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognize and abide by the legal requirements associated with these rights. •Users may download and print one copy of any publication from the Research Portal for the purpose of private study or research. •You may not further distribute the material or use it for any profit-making activity or commercial gain •You may freely distribute the URL identifying the publication in the Research Portal Take down policy If you believe that this document breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim.