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Non-Thermal Behavior in Conformal Boundary States
Prepared for submission to JHEP Non-Thermal Behavior in Conformal Boundary States Kevin Kuns and Donald Marolf Department of Physics, University of California, Santa Barbara, CA 93106, U.S.A. E-mail: [email protected], [email protected] Abstract: Cardy has recently observed that certain carefully tuned states of 1+1 CFTs on a timelike strip are periodic with period set by the light-crossing time. The states in question are defined by Euclidean time evolution of conformal boundary states associated with the particular boundary conditions imposed on the edges of the strip. We explain this behavior, and the associated lack of thermalization, by showing that such states are Lorentz-signature conformal transformations of the strip ground state. Taking the long- strip limit implies that states used to model thermalization on the Minkowski plane admit non-thermal conformal extensions beyond future infinity of the Minkowski plane, and thus retain some notion of non-thermal behavior at late times. We also comment on the holo- graphic description of these states. arXiv:1406.4926v2 [cond-mat.stat-mech] 6 Oct 2014 Contents 1 Introduction1 2 Periodicity and Tuned Rectangle States2 2.1 Tuned Rectangle States from Conformal Transformations2 2.2 One-Point Functions5 3 Conformal Transformations to the Thermal Minkowski Plane9 4 Discussion 12 A Holographic Description 13 1 Introduction The rapid change in a quantum system from a Hamiltonian H0 to a Hamiltonian H is known as a quantum quench. Quantum quenches are of experimental interest since they can be studied in laboratory systems involving ultracold atoms. They are also of theoretical interest as examples of out of equilibrium quantum systems whose thermalization, or lack thereof, can be used as a first step towards understanding thermalization in more general quantum systems. -
Lectures and Seminars, Trinity Term 2015
WEDNESDay 22 april 2015 • SUpplEMENT (2) TO NO 5092 • VOl 145 Gazette Supplement Lectures and Seminars, Trinity term 2015 Romanes Lecture 462 Experimental psychology Buddhist Studies Orthopaedics, rheumatology and COMPAS Musculoskeletal Sciences Hebrew and Jewish Studies University Administration pathology Hindu Studies and Services 462 pharmacology Museum of the History of Science Disability Lecture physiology, anatomy and Genetics islamic Studies population Health reuters institute for the Study of Humanities 462 psychiatry Journalism Foundation for law, Justice and Society TOrCH | The Oxford research Centre in Social Sciences 470 the Humanities learning institute Maison Française rothermere american institute interdisciplinary research Methods Oxford Martin School Classics Sanjaya lall Memorial Trust population ageing English language and literature anthropology and Museum Ethnography ian ramsey Centre History Saïd Business School linguistics, philology and phonetics Economics Colleges, Halls and Societies 482 Medieval and Modern languages Education Music interdisciplinary area Studies all Souls Oriental Studies international Development (Queen Balliol philosophy Elizabeth House) Green Templeton Theology and religion Oxford internet institute Keble Law lady Margaret Hall Mathematical, Physical and politics and international relations linacre Life Sciences 466 Social policy and intervention lincoln Socio-legal Studies Chemistry Magdalen Sociology Computer Science Mansfield Nuffield Earth Sciences Department for Continuing Queen’s Engineering -
A First Law of Entanglement Rates from Holography
A First Law of Entanglement Rates from Holography Andy O'Bannon,1, ∗ Jonas Probst,2, y Ronnie Rodgers,1, z and Christoph F. Uhlemann3, 4, x 1STAG Research Centre, Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ, U. K. 2Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, U. K. 3Department of Physics, University of Washington, Seattle, WA 98195-1560, USA 4Mani L. Bhaumik Institute for Theoretical Physics, Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA For a perturbation of the state of a Conformal Field Theory (CFT), the response of the entanglement entropy is governed by the so-called “first law" of entanglement entropy, in which the change in entanglement entropy is proportional to the change in energy. Whether such a first law holds for other types of perturbations, such as a change to the CFT La- grangian, remains an open question. We use holography to study the evolution in time t of entanglement entropy for a CFT driven by a t-linear source for a conserved U(1) current or marginal scalar operator. We find that although the usual first law of entanglement entropy may be violated, a first law for the rates of change of entanglement entropy and energy still holds. More generally, we prove that this first law for rates holds in holography for any asymptotically (d + 1)-dimensional Anti-de Sitter metric perturbation whose t dependence first appears at order zd in the Fefferman-Graham expansion about the boundary at z = 0. -
Reading in Fall 2003'S Inside Physics
FFromrom thethe ChairChair available in the fall of 2001. Visits elcome to the first edition of our by prospective students nearly newsletter, created to keep us in doubled the number for the newsletter, created to keep us in previous year, and 33 new Wclose touch with our alumni and graduate students appeared in the friends. We’d like to hear your reaction: fall of 2001. We were especially friends. We’d like to hear your reaction: pleased that 30% of the entering what’s satisfying, what’s not, what’s class were women. I hope this is missing. Please let us know. no “fluke” and that we continue missing. Please let us know. to increase the participation of women in physics. The applica- tions for the fall of 2002 number Jim Allen over 500 and we look forward to Department Chair enrolling another strong class. OUR FUTURE Three new faculty joined our als. And Walter himself, the EXCITING TIMES ranks: Crystal Martin, an observa- founding director of the Institute “You can dismiss one Nobel Prize tional astrophysicist from Caltech; for Theoretical Physics, received as a statistical fluke,” Walter Kohn David Stuart, a high energy the 1998 prize in chemistry. remarked, “but a spate of three experimental physicist from Fermi signals something important and Lab; and Dik Bouwmeester from exciting happening at UCSB.” ENDOWED CHAIR Oxford, who works on quantum We are delighted that a chair in The three Nobels reflect UCSB’s optics and experimental quantum experimental physics has been longstanding commitment to information science. We continue endowed by Bruce and Susan excellence in science and engi- to search for new faculty in Worster. -
Quantum Quenches: a Probe of Many-Body Quantum Mechanics
Tata Institute of Fundamental Research Hyderabad Colloquium John Cardy University of California, Berkeley Professor John Cardy is well known for his application of quantum field theory and the renormalization group to condensed matter, especially to critical phenomena in both pure and disordered equilibrium and non-equilibrium systems. In the 1980s he helped develop the theory of conformal invariance and its applications to these problems, ideas which also had an impact in string theory and the physics of black holes. In the 1990s he used conformal invariance to derive many exact results in percolation and related probabilistic problems. More recently Professor Cardy has worked on questions of quantum entanglement and non-equilibrium dynamics in many-body systems. He is a Fellow of the Royal Society, a recipient of the 2000 Dirac Medal of the Institute of Physics, of the 2004 Lars Onsager Prize of the American Physical Society, of the 2010 Boltzmann Medal of the International Union of Pure and Applied Physics, and of the 2011 Dirac Medal and Prize of the International Centre for Theoretical Physics. Professor Cardy has a long-standing association with TIFR, and visited our Mumbai campus in 2007-08 as the Homi Bhabha Chair Professor. Quantum Quenches: a probe of many-body quantum mechanics In a quantum quench, a system is prepared in some state (typically the ground state of an initial hamiltonian) and then evolved coherently with a different hamiltonian, e.g. by instantaneously changing a parameter. Such protocols in many-body systems have recently become experimentally achievable with ultracold atoms. I shall discuss some of the theoretical approaches to this problem, and in particular discuss whether, and in what sense, such systems thermalize. -
Beyond the Boson Graphene's 3D Counterparts Superconductivity
Autumn 2014, Number 5 Department of Physics Newsletter Beyond the boson The next steps for particle physics Superconductivity: Strike while the iron is hot Oxford researchers synthesise new iron based high temperature superconductor Graphene’s 3D counterparts Oxford researchers have discovered a new series of materials that are a 3D version of graphene ALUMNI STORIES EVENTS MOSELEY & X-RAYS PEOPLE Jean Chu (Holmes) reflects Alumni day at the Clarendon Part II of Prof Derek Stacey’s Five minutes with David Lloyd; on life as a female physics Laboratory; Bonn in Oxford; remarkable story celebrating Comings, Goings and Awards student at St Hugh’s, 1956–59 Alumni experience the LHC Henry Moseley’s work www.physics.ox.ac.uk SCIENCE NEWS SCIENCE NEWS www.physics.ox.ac.uk/research www.physics.ox.ac.uk/research in research labs, to steering oxides were shown to exhibit superconductivity the beams around particle at temperatures well above 100 Kelvin (a accelerators (such as the phenomenon which is still far from understood). SUPERCONDUCTIVITY: Large Hadron Collider at CERN) and confining the EXPLORING NEW PHYSICS STRIKE WHILE THE IRON IS HOT plasma in a fusion reactor. But perhaps their most Here in Oxford our current focus is on the newly important application has A little over a century after the discovery of quantum coherent state, a concept also applicable to discovered materials that contain iron. Some been in magnetic resonance superconductivity we are still missing some vital superfluids and Bose-Einstein condensates of cold of these have transition temperatures above imaging (MRI), the clues in understanding how and why the effect atoms. -
Parliamentary Debates (Hansard)
Thursday Volume 566 18 July 2013 No. 39 HOUSE OF COMMONS OFFICIAL REPORT PARLIAMENTARY DEBATES (HANSARD) Thursday 18 July 2013 £5·00 © Parliamentary Copyright House of Commons 2013 This publication may be reproduced under the terms of the Open Parliament licence, which is published at www.parliament.uk/site-information/copyright/. 1295 18 JULY 2013 1296 Vince Cable: The hon. Gentleman is correct to say House of Commons that our overall export performance would improve considerably if more British companies were exporting. The big contrast with Germany is that roughly twice as Thursday 18 July 2013 many of its small and medium-sized enterprises are involved in exporting. UKTI has been substantially The House met at half-past Nine o’clock reformed in the past couple of years, and it now has a much more small and medium-sized company focus. It has activities around the country, and we have a lot of PRAYERS evidence that its outreach is substantially improving. I hope that it will reach the companies in the hon. Gentleman’s constituency too. [MR SPEAKER in the Chair] Mr Iain Wright (Hartlepool) (Lab): At the last Business, Innovation and Skills questions, the Secretary of State Oral Answers to Questions admitted: “The figures on exports are not great”.—[Official Report, 13 June 2013; Vol. 564, c. 470.] Since then, the UK trade deficit has widened to the BUSINESS, INNOVATION AND SKILLS point at which it is now the largest trade gap in the European Union, and the widest it has been since 1989. Following on from the question from my hon. -
Extracting Cosmology from High Resolution CMB Data *Focused on ACT and SO
Extracting cosmology from high resolution CMB data *focused on ACT and SO Jo Dunkley, Princeton University May 23, 2018 Jo Dunkley Cosmic Microwave Background T=2.7K ∆T/T ~0.00001 Also polarization: Rep.Two-point statistics: Prog. Phys. 81 (2018) 044901 Report on Progress TxT TxE BxB ExE Staggs, JD, Page 2018 review Figure 3. Example of recent CMB power spectra from [50–54]. Left. TT (top) and EE (bottom) data and power spectra plotted with logarithmic y axes. The TT and EE oscillations are out of phase by ∼π/2 as expected for acoustic oscillations (see section 1.4) since TT and EE trace density and velocity, respectively. The TT spectrum at low ℓ, corresponding to superhorizon scales at decoupling (see section 2.1), has post-decoupling contributions from gravitational redshifting of the photons as they pass through evolving potential wells, known as the integrated Sachs-Wolfe (ISW) effect [55, 56]. The EE spectrum peaks at higher ℓ than TT both because it lacks the ISW effect, and because the acoustic oscillation velocity gradients sourcing the polarization grow with k and thus with ℓ. The spectra are suppressed at large ℓ due to photon diffusion from smaller regions of space, also called Silk damping [57], and to geometric effects from compressing the 3d structure to 2d spectra. Right. TE with linear y axis. Since the ISW effect does not change the polarization, the negative peak at ℓ = 150 in TE confrmed that some of the largest scale features in the CMB are primordial, and not just late-time effects [58–60]. -
Neutrino Cosmology and Large Scale Structure
Neutrino cosmology and large scale structure Christiane Stefanie Lorenz Pembroke College and Sub-Department of Astrophysics University of Oxford A thesis submitted for the degree of Doctor of Philosophy Trinity 2019 Neutrino cosmology and large scale structure Christiane Stefanie Lorenz Pembroke College and Sub-Department of Astrophysics University of Oxford A thesis submitted for the degree of Doctor of Philosophy Trinity 2019 The topic of this thesis is neutrino cosmology and large scale structure. First, we introduce the concepts needed for the presentation in the following chapters. We describe the role that neutrinos play in particle physics and cosmology, and the current status of the field. We also explain the cosmological observations that are commonly used to measure properties of neutrino particles. Next, we present studies of the model-dependence of cosmological neutrino mass constraints. In particular, we focus on two phenomenological parameterisations of time-varying dark energy (early dark energy and barotropic dark energy) that can exhibit degeneracies with the cosmic neutrino background over extended periods of cosmic time. We show how the combination of multiple probes across cosmic time can help to distinguish between the two components. Moreover, we discuss how neutrino mass constraints can change when neutrino masses are generated late in the Universe, and how current tensions between low- and high-redshift cosmological data might be affected from this. Then we discuss whether lensing magnification and other relativistic effects that affect the galaxy distribution contain additional information about dark energy and neutrino parameters, and how much parameter constraints can be biased when these effects are neglected. -
Review of the Year 2009/10
Invest in future scientific leaders and in innovation Review of the year 2009/10 1 Celebrating 350 years Review of the year 2009/10 02 Review of the year 2009/10 President’s foreword Executive Secretary’s report Review of the year 2009/10 03 Contents President’s foreword ..............................................................02 Inspire an interest in the joy, wonder Executive Secretary’s report ..................................................03 and excitement of scientific discovery ..................................16 Invest in future scientific leaders and in innovation ..............04 Seeing further: the Royal Society celebrates 350 years .......20 Influence policymaking with the best scientific advice ........08 Summarised financial statements .........................................22 Invigorate science and mathematics education ...................10 Income and expenditure statement ......................................23 Increase access to the best science internationally ..............12 Fundraising and support ........................................................24 List of donors ..........................................................................25 President’s Executive foreword Secretary’s report This year we have focused on the excellent This has been a remarkable year for the Society, our opportunity afforded by our 350th anniversary 350th, and we have mounted a major programme not only to promote the work of the Society to inspire minds, young and old alike, with the but to raise the profile of science -
Parliamentary Debates House of Commons Official Report General Committees
PARLIAMENTARY DEBATES HOUSE OF COMMONS OFFICIAL REPORT GENERAL COMMITTEES Public Bill Committee ENTERPRISE AND REGULATORY REFORM BILL Third Sitting Thursday 21 June 2012 CONTENTS Written evidence reported to the House. Examination of witnesses. Adjourned till Tuesday 26 June at half-past ten o’clock. PUBLISHED BY AUTHORITY OF THE HOUSE OF COMMONS LONDON – THE STATIONERY OFFICE LIMITED £5·00 PBC (Bill 007) 2012 - 2013 Members who wish to have copies of the Official Report of Proceedings in General Committees sent to them are requested to give notice to that effect at the Vote Office. No proofs can be supplied. Corrigenda slips may be published with Bound Volume editions. Corrigenda that Members suggest should be clearly marked in a copy of the report—not telephoned—and must be received in the Editor’s Room, House of Commons, not later than Monday 25 June 2012 STRICT ADHERENCE TO THIS ARRANGEMENT WILL GREATLY FACILITATE THE PROMPT PUBLICATION OF THE BOUND VOLUMES OF PROCEEDINGS IN GENERAL COMMITTEES © Parliamentary Copyright House of Commons 2012 This publication may be reproduced under the terms of the Parliamentary Click-Use Licence, available online through The National Archives website at www.nationalarchives.gov.uk/information-management/our-services/parliamentary-licence-information.htm Enquiries to The National Archives, Kew, Richmond, Surrey TW9 4DU; e-mail: [email protected] Public Bill Committee21 JUNE 2012 Enterprise and Regulatory Reform Bill The Committee consisted of the following Members: Chairs: HUGH BAYLEY,†MR -
Parliamentary Debates (Hansard)
Monday Volume 552 5 November 2012 No. 63 HOUSE OF COMMONS OFFICIAL REPORT PARLIAMENTARY DEBATES (HANSARD) Monday 5 November 2012 £5·00 © Parliamentary Copyright House of Commons 2012 This publication may be reproduced under the terms of the Open Parliament licence, which is published at www.parliament.uk/site-information/copyright/. 571 5 NOVEMBER 2012 572 compensation. Does my hon. Friend agree that the House of Commons position is unfair and should be reviewed by HMRC? Monday 5 November 2012 Steve Webb: I am grateful to my hon. Friend for raising that case. I have corresponded with Treasury The House met at half-past Two o’clock colleagues about the issue, and, subject to their consent, I shall be happy to share with him the reply that I have PRAYERS just received. [MR SPEAKER in the Chair] Disability Strategy 2. Stuart Andrew (Pudsey) (Con): What progress he Oral Answers to Questions has made on the Government’s disability strategy. [126299] WORK AND PENSIONS The Parliamentary Under-Secretary of State for Work and Pensions (Esther McVey): Fulfilling Potential, our The Secretary of State was asked— disability strategy, is being co-produced with disabled people. We published “Fulfilling Potential—The Discussions UK Pension-holders So Far” and “Fulfilling Potential—Next Steps” on 17 September. Our key themes, which we intend to 1. Dan Jarvis (Barnsley Central) (Lab): What steps he make a real difference, are early intervention, choice is taking to ensure that foreign conglomerates carry out and control, and inclusive communities. their responsibilities to UK pension-holders. [126298] The Minister of State, Department for Work and Stuart Andrew: Can the Minister explain what the Pensions (Steve Webb): As this is the first session of role of the disabled people’s user-led organisations will DWP questions since the announcement of the untimely be in the strategy? death of Malcolm Wicks, I hope that you will allow me, Mr.