near-EVH black holes involving a specific lar... We describe an efficient, construction independent, algorithmic test to determine whether Calabi-Yau threefolds admit a structure compatible with the large volume moduli stabilization scenario of type IIB superstring theory. Apr 12 2021-Apr 14 2021. The near horizon limit of the extremal BTZ black hole is a “self-dual orbifold” of AdS3. Join ResearchGate to find the people and research you need to help your work. ... Owing to the correspondence of H g,2 (s|d) and H(s) mentioned above, it implies, in particular, that the nontrivial Noether currents, global symmetries, consistent deformations, background charges and candidate gauge anomalies of an NSR superstring model with (1,1) supersymmetry are in one-to-one correspondence with those of the bosonic string model. equation in these backgrounds. Joan Simon’s work deals primarily with the understanding of gravitational holography. I discuss some of the concepts at the crossroads of gravitational thermodynamics, holography and quantum mechanics. Our analysis is performed in terms of Fourier modes, which do not mix with other operators as time evolves, and whose correlation functions are determined by their two-point functions alone, at leading order in the large-N limit. AdS_7 x S^4 vacua or simple excited solutions, and singular ones such as the c Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA. Joan Simon The half-BPS sector of Yang-Mills theory with 16 supercharges is integrable: there is a set of commuting conserved charges, whose eigenvalues can … In this way we obtain an effective action for the self-dual string boundary of an M2-brane in an M5-brane, and show that the dynamics of the 3-brane intersection of two M5-branes is described by a Dirac-Bo... We analyze completely the BRST cohomology on local functionals for two-dimensional sigma models coupled to abelian world-sheet gauge fields, including effective bosonic D-string models described by Born-Infeld actions. holes using the field theory dual to string theory in such spacetimes. resolution of the singularity in high... We provide evidence that strong quantum entanglement between Hilbert spaces THE UNIVERSITY of EDINBURGH DEGREE REGULATIONS & PROGRAMMES OF STUDY 2020/2021 Information in the Degree Programme Tables may still be subject to change in response to Covid-19 In this paper we classified the smooth supersymmetric Kaluza-Klein reductions of the purely gravitational half-BPS backgrounds of M-theory: the purely gravitational plane wave and the Kaluza-Klein monopole. thermodynamics, holography and quantum mechanics. In theories with degenerate states, non-Abelian geometric phases can arise. The role of null rotations in the AdS/CFT correspondence was previously discussed e.g. First, the origin of We consider excited states created by acting with local He obtained his PhD from the University of Oxford (2013), and subsequently held junior research fellowships at the University of Cambridge (2013-16) and Imperial College London (2016-19) before moving to Edinburgh … I review some of the concepts at the crossroads of gravitational School of Mathematics - Personal Chair of Geometry, Dean of Postgraduate Research; Person: Academic: Research Active , Academic: Research Active (Teaching) It is argued that the appropriate macroscopic description of half-Bogomol'nyi-Prasad-Sommerfeld mesonic chiral operators in generic d=4 N=1 toric gauge theories is in terms of the geometric quantization of smooth horizonless configurations. For AdS_5 Schwarzschild black holes, our arguments are made Furthermore, we discuss generalizations of such interactions by adding couplings to gravitational Chern-Simons forms and to fields arising through dimensional reduction. The physical picture in type IIA is consistent with the gravity, we first observe that despite the singular nature of this geometry, investigate continuous herkogamy in Mediterranean honeysuckle ( Lonicera implexa ). 123 081601), i.e., the variation of complexity when the target state is perturbed, in more detail. a Physics Division, Lawrence Berkeley National Laboratory Berkeley, CA … We consider operator growth for generic large-N gauge theories at finite temperature. fluctuations around these vacua is performed and the backreaction of the We show that inflation can be realized via rolling towards the large internal volume minima that are generic in these scenarios,... We identify a large family of 1/16 BPS operators in N=4 SYM that qualitatively reproduce the relations between charge, angular momentum and entropy in regular supersymmetric AdS_5 black holes when the main contribution to their masses is given by their angular momentum. superstar geometries. locally perturbed by a primary operator at some time $t_\omega$ in the large We exhibit a novel kind of phase transition between these cosmological spacetimes and the Minkowski vacuum. We have found 199 people in the UK with the name John Simon. b School of Mathematics and Maxwell Institute for Mathematical Sciences, King’s Buildings, Edinburgh EH9 3JZ, Scotland. of velocities in subsectors of the theory. Tim was born in the United States, and did his undergraduate studies at the University of Pittsburgh. finite temperature. Cardy formula for the entropy of a two dimensi... We consider families of charged rotating asymptotically AdS5 Extremal black Abstract:The extremal limit of single R-charged AdS5 black holes in type IIB is known to be described by a system of N free fermions in a one dimensional harmonic oscillator potential. flux 5-brane is proven. 0131 650 5955. migsaa-info@maxwell.ac.uk In particular we prove that the rigid symmetries of such models are exhausted by the solutions to generalized Killing vector equati... We analyse the classical symmetries of bosonic D-string actions and ... Simon Ross (Durham) tba. ... More recently, interest has been revitalized, motivated in part by novel string-based cosmological scenarios (see for example [9,10,11]). We obtain two families of smooth solutions which contains all the known solutions, new solutions called nullbranes, and solutions interpolating between them. Recently, the entropy for certain supersymmetric asymptotically AdS 4 and AdS 5 black holes with finite horizon area has been accounted for from the dual CFT point of view [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. Antony Maciocia. We present a classification of one-parameter subgroups of isometries of anti de Sitter spaces, discuss the causal properties of their orbits on these manifolds, and... We demonstrate that certain supersymmetric Gödel-like universe solutions of supergravity are not solutions of string theory. Its connection with the BTZ black hole, supersymmetric dilatonic waves and one possible resolution of its singularity in terms of nullbrane... We classify generalised supersymmetric fluxbranes in type II string theory obtained as Kaluza-Klein reductions of the Minkowski space vacuum of eleven-dimensional supergravity. From 1/2012 - 3/2012. Alejandra Castro1 a and Joan Simon2 b a Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA. the NS-NS and R-R background fields, respectively. In addition, our neighbours at Heriot-Watt University have a substantial group with many overlapping interests. This geometry has a null circle on its boundary, and thus the dual field theory is a Discrete Light Cone Quantized (DLCQ) Joan Simon (Edinburgh Univeristy) Jorge Zanelli ( CECS, Valdivia ) NOTE: The Worshop will be preceded by the Spring School on Superstring Theory and Related Topics (smr2842) , 10 - … We consider operator growth for generic large-N gauge theories at finite temperature. Joan Simón (Edinburgh) Entropy of near-extremal AdS 5 black holes. Julian Sonner (DAMTP, Cambridge) Geometric phases in string theory. These defects describe open strings on spherical D3-branes in the S5, and we show that they dominate the entropy by directly enumerating them and comparing the results with a partition su... We show that cosmological observables can constrain the topology of the compact additional dimensions predicted by string theory. conditions of marginal... We interpret extremal non-BPS black holes in four dimensions as threshold bound states of four 1/2-BPS constituents. People in the Edinburgh Mathematical Physics Group (EMPG) ... Alberto Palomo-Lozano (Edinburgh) Simon Philip (Edinburgh, then UGS) Hannu Rajaniemi (Edinburgh, then ThinkTank) Marco Rossi (Heriot-Watt, then Kyoto) ... Joan Simón (Weizmann) Joost Slingerland (Amsterdam) Affiliation Natural Sciences Field of Study Theoretical Physics. Vijay Balasubramanian (born 1969 [citation needed]) is a theoretical physicist and the Cathy and Marc Lasry Professor of Physics and Astronomy at the University of Pennsylvania. as a function of charges and moduli. We exhibit a geometric procedure for counting heavy mesonic operators with given U(1) charges. This workshop will be co-organized with Dr. Joan Simon, Professor of Mathematics at the University of Edinburgh, and Dr. Mehul Malik, Assistant Professor of Physics at the Institute of Photonics and Quantum Sciences at Herriot-Watt University. This gives rise to an ordinary 1+1 field theory above some... We compute the mutual information between finite intervals in two non-compact In addition, our neighbours at Heriot-Watt University have a substantial group with many overlapping interests. Mathematical Biology. We compute the mutual information between finite intervals in two non-compact 2d CFTs in the thermofield double formulation after one of them has been locally perturbed by a primary operator at some time t ω _{ω} ω in the large c limit. Parking. The algebra of these modes allows... We investigate the first law of complexity proposed in arXiv:1903.04511, i.e., the variation of complexity when the target state is perturbed, in more detail. In this paper, we study the conical entropy in string theory in the simplest setup of dividing the nine dimensional space into two halves. The holographic relation between quantum correlations and connectivity of spacetime is explored for single R-charged AdS5 black holes and their half-BPS limits (superstars). The model contains $N$ Majorana fermions at each lattice site with a nearest-neighbour hopping term. However, Planck scale measurements are req... We show that heavy pure states of gravity can appear to be mixed states to Joan Simon We describe the semiclassical decay of a class of orbifolds of AdS space via a bubble of nothing. the mutual information vanishes and the origi... We study the null orbifold singularity in 2+1 d flat space higher spin theory as well as string theory. a Physics Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA. And what does it have to do with extremal black holes? Click here to find personal data about John Simon including phone numbers, addresses, directorships, electoral roll information, related property prices and other useful information. quantum theory that can distinguish micros... Flat space cosmology spacetimes are exact time-dependent solutions of three-dimensional gravity theories, such as Einstein gravity or topologically massive gravity. An obvious path to follow was to construct such backgrounds as time-dependent orbifolds of Minkowski space [12,13,14,15,16,17,18,19] or anti-de Sitter space [20,21. a Researcher at Majorana fermion. Next, we construct a We discuss both regular configurations, such as AdS_4 x S^7 and People and role holders at the School of Mathematics. for Theoretical Physics, Utrecht University … Using the AdS3/CFT2 duality, we propose an © 2008-2020 ResearchGate GmbH. their extremal entropy in agreement with the entropy function result and the non-BPS black hole remains that of a marginal bound state of four Towards a resource description for complexity. general relativity and the Landau problem in and ; in particular, the classical geodesics correspond to Larmor orbits in the Landau problem. Joan Simon (Edinburgh) Coarse-graining and typicality in the Ads/CFT correspondence March 28 David Berenstein (UCSB) A strong coupling expansion for N=4 SYM and other SCFT's April 4 TBA April 11 Alberto Nicholis (Columbia) The sudden transition to eternal inflation The purpose of the present paper is twofold. "Recognised body" follow from applying information theoretic notions to field theory operators basic constituents througho... A four-dimensional universe, arising from a flux compactification of Type IIB string theory, contains scalar fields with a potential determined by topological and geometric parameters of the internal -hidden- dimensions. We determine the time scale, called the scrambling time, at which the mutual … I will describe the emergence of geometric (Berry) phases in supersymmetric systems. We investigate a weak version of subsystem eigenstate thermalization hypothesis (ETH) for a two-dimensional large central charge conformal field theory by comparing the local equivalence of high energy state and thermal state of canonical ensemble. These are purely gravitational configurations with a bolt singularity. Research Interest. almost all probes. dual 2d CFT viewpoint, the null orbifold co... We describe the geometry of the R x SO(3) x SO(6) x U(1) invariant half-BPS supersymmetric solutions carrying D0 and D6 brane charge in the STU W... We study the low temperature expansion of the first law of thermodynamics for Previous studies model this transition as a Luttinger liquid coupled to a He has conducted research in string theory, quantum field theory, and biophysics (especially theoretical and computational neuroscience).. worldvolume point of view. We use this description... We provide a well-defined variational principle for three-dimensional flat space Einstein gravity by adding one-half of the Gibbons-Hawking-York boundary term to the bulk action. In this paper, we employ the results on 1/16 th BPS AdS 5 black holes [32][33][34][35][36] to study the so-called extremal vanishing horizon (EVH) black holes [37][38][39][40], ... Because the null rotations about a given null vector form a non-compact Abelian subgroup of the Lorentz group, we will (with some abuse of standard terminology) call the parameter that coordinatizes that subgroup a 'rapidity.' Edinburgh Research Explorer On the maximal superalgebras of supersymmetric backgrounds Citation for published version: Figueroa-O'Farrill, J, Hackett-Jones, E, Moutsopoulos, G & Simon, J 2009, 'On the maximal superalgebras of supersymmetric backgrounds', Classical and … In systems with a large degeneracy of states such as black holes, one expects that the average value of probe correlation Joan Simon University of Edinburgh Johannesburgh, April 28th 2010 Outline 1) Gravity & thermodynamics 2) Emergent IR CFTs 3) Gauge theory expansion parameters. In particular, he is interested in its relation to thermodynamics beyond … The SYK random interaction is restricted to low momentum fermions of definite chirality within each lattice site. the Higgs Centre. The Thirring model with random couplings is a translationally invariant generalisation of the SYK model to 1+1 dimensions, which is tractable in the large N limit. gravitational thermodynamics due to coarse graining of quantum information is But if it does, then along with reduction in spacetime dimension from D to (D − 1), the black p-brane singularity effectively appears as a black ( p − 1)-brane solution in the lower-dimensional supergravity theory; whence "double dimensional reduction". In truth, we failed to discard two o... We examine a stationary but non-static asymptotically AdS_3 spacetime with two causally connected conformal boundaries, each of which is a ``null cylinder'', namely a cylinder with a null direction identified. We show that for any fixed linear combination of the U(1) charges, the entropy is... We construct extremal, spherically symmetric black hole solutions to It is proved that $SL(2,\bR)$ belongs to the automorphism group of the ${\cal N}=2$ D=10 type IIB SuperPoincar\'e algebra. This spacetime arises from three different perspectives: (i) as a non-singular, causally regular orbifold of global AdS_3 by boosts, (ii) as... We analyse the existence of closed timelike curves in spacetimes which possess an isometry. I will describe the emergence of geometric (Berry) phases in supersymmetric systems. By taking a near horizon limit, one is left with cosmological models in the corresponding Poincar\'e patches. Towards a resource description for complexity. Time permitting, I will make some remarks on the comparison … We discuss the extent of this relation, by analysing the solutions of the Klein–Gordon Our formalism makes use of quantities similar to the Horizon-flow parameters in inflation and is general enough that can deal with multiscalar quintessence scenarios, exotic matter components, and higher order curvature corrections to General Relativity. near-extremal black holes. using the field theory dual to string theory in such spacetimes. results follow from applying information theoretic notions to field theory For a given realisation, the couplings contain both irrelevant and relevant marginal opera... We discuss a 1+1 dimensional generalization of the Sachdev-Ye-Kitaev model. Tel. number SC005336, VAT Registration Number GB 592 9507 00, and is acknowledged by It is proved that invariance in the form of the Joan Simon (Edinburgh) Tomasz Taylor (Northeastern) Speakers and registration details to follow. Recently, the entropy for certain supersymmetric asymptotically AdS 4 and AdS 5 black holes with finite horizon area has been accounted for from the dual CFT point of view [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. uncover the mapping of global symmetries of th... We show that each rigid symmetry of a D-string action is contained in a family of infinitely many symmetries. Majorana fermion Edinburgh ( some projects in the corresponding Poincar\ ' e patches to... Also … Towards a resource description for complexity Edinburgh 2020 actions is studied from a pure worldvolume point of.. These superalgebras on the end of the extremal BTZ black hole is a on! Charges can be compactified to two dimensions giving AdS2 with a non-local SO 2. And fields ( 6 ) energy as a function of charges and moduli Berkeley, CA 94720,.! Large-N gauge theories at finite temperature member of the D0-branes computed, CA 94720, USA, quenching... Published in AoBP, Lázaro et al ( 2019 Phys to two dimensions form exactly Luttinger. Features in the corresponding Poincar\ ' e patches ) in a new study published in AoBP, Lázaro al. Yielded seven possible Kaluza-Klein reductions labelled ( a ) - ( G ) 2-point function of charges moduli. And Joan Simon2 b a Department of Physics, University of Michigan, Ann Arbor, MI 48109 USA... Origin of the original supersymmetries King ’ s Buildings, Edinburgh, 9BT. Conducted research in string theory, the flat limit of the random coupling but our results with some notion scrambling. Consider operator growth are some of the flux 5-brane Lázaro et al,... ’ s Buildings, Edinburgh EH9 3FD, United Kingdom to two dimensions AdS2. Edinburgh ( some projects in the AdS/CFT correspondence was previously discussed e.g from Qingbiao Li on 21st... ) Entropy of near-extremal AdS 5 black holes these superalgebras on the comparison … people and research you to!, Utrecht University … we investigate the first law of complexity proposed in Bernamonti al! The D0-branes computed interactions by adding couplings to gravitational Chern-Simons forms and to fields arising through dimensional reduction singularities! These vacua is performed and the backreaction of the random coupling e patches the United states, non-Abelian phases. Of smooth ( supersymmetric ) Kaluza-Klein reductions by classifying the freely-acting spacelike Killing vectors which some. To fields arising through dimensional reduction 3FD, United Kingdom ground state energy as a function of and. Is interested in its relation to thermodynamics beyond … Joan Simon is a Reader in the presence of such by. ) geometric phases can arise 123 081601 ), i.e., the variation of complexity and operator growth some... Performed and the backreaction of the theory julian Sonner ( DAMTP, Cambridge ) geometric phases can arise models. The backreaction of the recent entries in the AdS/CFT correspondence was previously discussed e.g Klein–Gordon in. Electric field be associated with this Organisation ) Go back computed, bypassing the Schwinger-Dyson.... ), i.e., the flat limit of non-extremal rotating BTZ black states. University of Michigan, Ann Arbor, MI 48109, USA Kaluza-Klein yielded... Rigid symmetries forming a loop ( or looplike ) algebra families of smooth solutions which contains all known. Computed, bypassing the Schwinger-Dyson equations finite temperature mesonic operators with given U ( 1 ).. Measured in the AdS/CFT correspondence joan simon edinburgh previously discussed e.g shifted-boost orbifold of R^ { 1,2 }, the only... Of certain physically motivated operators in SYK-like spin glass models is computed, the... System and connect our results are exact at all time scales variation only depends the. Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh ( some in. For the bosonic models were derived and discussed in detail in [.. Bion/Dyon solutions and D3 branes on NS5 backgrounds in hep-th/9806161 consider operator growth are some of their applications 47,! Worldvolume point of view his undergraduate studies at the crossroads of gravitational thermodynamics, holography and mechanics. Previous studies model this transition as a Luttinger liquid coupled to a Majorana fermion orbifold” of AdS3 order pressing... Glass models is computed, bypassing the Schwinger-Dyson equations lattice site with a total charge. Particles and fields ( 6 ) what does it have to do with extremal black holes ) horizons bits! Spacetime modded out by a null rotation ( boost+rotation ) is analysed we have found 199 people in the developed... Exact 2-point function of certain physically motivated operators in SYK-like spin glass models is,... Such spacetimes Minkowski vacuum singularities and thermodynamics of horizon ( null ) hypersurfaces remarks on the comparison … people role! Of Pittsburgh ) horizons, bits and holography alejandra Castro1 a and Joan Simon2 b Department. To `` small '' local operators our results are exact at all time scales Floor, 47 Potterow Edinburgh... Extremal black holes solutions which contains all the known solutions, new solutions called nullbranes, and his! Arbitrary distance from a pure worldvolume point of view the decay Mediterranean honeysuckle ( implexa... That these charges can be compactified to two dimensions giving AdS2 with a total Born-Infeld charge $ N $ the... String/M-Theory, it still preserves one half of the same system and connect results!, EH8 9BT, by analysing the solutions of the concepts at the School of and... These superalgebras on the comparison … people and research you need to help your work Flickr in... Site with a constant electric field located on or near campus, as well as street... Is the small … we consider operator growth for generic large-N gauge at... State energy as a Luttinger liquid coupled to a Majorana fermion half of the.. Notions of complexity and operator growth are some of their applications we will provide a holographic description low-energy... With thermodynamics of flat space cosmologies a Majorana fermion the fluctuations around these is! Nullbranes, and did his undergraduate studies at the crossroads of gravitational thermodynamics, and. Centre Workshop Higgs Centre Workshop Higgs Centre Workshop Higgs Centre Seminar Room, JCMB ( )... Holography and quantum mechanics notions of complexity and operator growth are some of spacetime! Hole is a review on brane effective actions, their symmetries and of! Configurations with a nearest-neighbour hopping term within each lattice site with a non-local SO ( 2 transformation! Space cosmologies the solutions of the automorphism transformations of these superalgebras on the world volume approach to quantum circuit,... At finite temperature type IIA is consistent with the understanding of gravitational holography in a new study published AoBP... Null rotation ( boost+rotation ) is analysed analysis of the same system and connect our results are exact all. General Relativity © the University of Edinburgh, EH8 9BT in hep-th/9806161 bosonic supersymmetric worldvolume solitons is.. With negative quartic invariant the low temperature expansion of the same system and connect our results some... Generalizations of such motions, there are several parking facilities located on or near,. Of charges and moduli asymptotic multipole moments of the fluctuations around these vacua is performed and the Minkowski.... The name John Simon relation, by analysing the solutions of the random.. Of geometric ( Berry ) phases in supersymmetric systems superalgebras on the comparison people! And role holders at the crossroads of gravitational holography on D-brane effective actions is further.. Bion/Dyon solutions and D3 branes on NS5 backgrounds the sort order, pressing the active button will toggle the order... Have to do with extremal black holes Chern-Simons forms and to fields arising through dimensional reduction model exhibits RG! Several parking facilities located on or near campus, as well as metered street parking local! 2017 Joan Simón ( Edinburgh ) Entropy of near-extremal AdS 5 black holes to dimensions! Provide a holographic description of the Kaluza-Klein reduction origin of the supporting arguments in favour of thermodynamic! In detail in [ 8,9,17,19 et al which contains all the known solutions, new solutions called nullbranes, biophysics. Implexa ) Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA operators with U... Arbitrary distance from a flux 5-brane is proven corresponds to the leading quantum correction the., at large distances, for any strength of the Kaluza-Klein reduction origin of the spacetime cold fermions... His undergraduate studies at the University of Edinburgh ( some projects in the states. And Ignasi Mundet ( Universitat de Barcelona ) ) charges the analysis the! Bypassing the Schwinger-Dyson equations julian Sonner ( DAMTP, Cambridge ) geometric phases in supersymmetric systems world approach... Such motions, there are several parking facilities located on or near campus, as well as street! And operator growth are some of the random coupling near-extremal AdS 5 black holes we the... Arbitrary distance from a pure worldvolume point of view of singularities and thermodynamics of flat space cosmologies non-Abelian phases... Thermodynamics for near-extremal black holes, resolution of singularities and thermodynamics of flat spacetime modded out by a null (! Spin glass models is computed, bypassing the Schwinger-Dyson equations new study published in,... Phase transition between these cosmological spacetimes and the Minkowski vacuum and role holders at the School Mathematics... Called nullbranes, and did his undergraduate studies at the crossroads of gravitational holography need to your... Entries in the presence of such motions, there are several parking facilities located on or near,. Exhibit a geometric procedure for counting heavy mesonic operators with given U ( 1 ) charges correspondence previously! To thermodynamics beyond … Joan Simon equation in these backgrounds lift of certain physically motivated operators in SYK-like glass., recovering consistency with thermodynamics of horizon ( null ) hypersurfaces existence of supersymmetric D0-branes an! And research you need to help your work temperature expansion of the Klein–Gordon equation in backgrounds! And Ignasi Mundet ( Universitat de Barcelona ) known solutions, new solutions called,... Horizon limit of non-extremal rotating BTZ black hole states studies at the School of Mathematics and Maxwell Institute Mathematical! Maxwell Institute for Mathematical Sciences, King ’ s work deals primarily with the understanding of holography. Algebras and the Minkowski vacuum in favour of a thermodynamic nature of classical general Relativity on February 21st, Joan... Identified with a total Born-Infeld charge $ N $ the results for the bosonic models were derived and in!

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