BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Large N Qudit Complexity and Symmetry Resolution in AdS3 DTSTART;VALUE=DATE-TIME:20230523T143000Z DTEND;VALUE=DATE-TIME:20230523T153000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-244@indico.ift.uam-csic.es DESCRIPTION:Speakers: René Meyer ()\nThe fact black holes carry statistic al entropy proportional to their horizon area implies that quantum informa tion concepts are geometrized in gravity. This idea obtains a particular m anifestation in the AdS/CFT correspondence\, where it is believed that the quantum information content in the dual field theory state can be used to reconstruct the bulk space-time geometry. The calculation of entanglement entropy from geodesics in the bulk space-time has clarified this idea to some extent.\n\nIn this talk\, I will consider two aspects of quantum info rmation theory in relation to holography:\n\nFirst\, I will discuss the la rge N limit of Nielsen's operator complexity on the SU(N) manifold\, with a particular choice of cost function based on the Laplacian on the Lie alg ebra\, which leads to a polynomial (instead of exponential) penalty factor s. I will first present numerical results that hint at the existence of ch aotic and hence ergodic geodesic motion on the group manifold\, as well sh ow the existence of conjugate points. I will then discuss a mapping betwee n the Euler-Arnold equation which governs the geodesic evolution\, to the Euler equation of two-dimensional idea hydrodynamics\, in the strict large N limit.\n\nSecond\, I will discuss a refinement of entanglement entropy for systems with conserved charges\, the so-called symmetry-resolved entan glement. It measures the entanglement in a sector of fixed charge. I will present how to calculate the symmetry-resolved entanglement in two-dimensi onal conformal field theories with Kac-Moody symmetry\, and also within W_ 3 higher spin theory. I will also discuss the geometric realization in the dual AdS space-time\, as well as recent results including the full expans ion in the UV cutoff. I will close with some comments on how symmetry reso lution could be applied to quantum computational complexity.\n\nhttps://in dico.ift.uam-csic.es/event/18/contributions/244/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/244/ END:VEVENT BEGIN:VEVENT SUMMARY:A bulk manifestation of Krylov complexity DTSTART;VALUE=DATE-TIME:20230523T083000Z DTEND;VALUE=DATE-TIME:20230523T093000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-241@indico.ift.uam-csic.es DESCRIPTION:Speakers: Adrián Sánchez Garrido ()\nThe double-scaled SYK ( DSSYK) model provides an analytically tractable instance of low-dimensiona l holography in which the existence of an expansion in terms of chord diag rams allows for an explicit construction of both the bulk Hilbert space an d the Hamiltonian of JT gravity from the boundary theory. In this talk\, I will present recent results that build up on this framework and propose a precise entry for Krylov complexity in the holographic dictionary. I will show that the eigenstates of the Krylov complexity operator are identifie d with the fixed chord number states that build up the effective Hilbert s pace of DSSYK\, therefore providing bulk length eigenstates once they are subject to the bulk/boundary map. This allows to compute the profile of bu lk length as a function of time in terms of the boundary K-complexity. For the sake of completeness\, a concise review on the necessary notions of K -complexity will also be provided.\n\nhttps://indico.ift.uam-csic.es/event /18/contributions/241/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/241/ END:VEVENT BEGIN:VEVENT SUMMARY:Holographic entanglement entropy and complexity in the context of braneworld models DTSTART;VALUE=DATE-TIME:20230524T143000Z DTEND;VALUE=DATE-TIME:20230524T153000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-248@indico.ift.uam-csic.es DESCRIPTION:Speakers: Juan Hernandez ()\nWe overview some lessons about en tanglement entropy and holographic complexity in various braneworld models . In particular\, we focus on the easy island model\, interpreting the lea ding contribution of the entanglement entropy and complexity in the island phase. We also look at black holes with end-of-the world branes behind th e horizon\, and consider consequences of the Lloyd bound on complexity as well as the entanglement velocity bound in these models.\n\nhttps://indico .ift.uam-csic.es/event/18/contributions/248/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/248/ END:VEVENT BEGIN:VEVENT SUMMARY:Spacetime as a quantum circuit? DTSTART;VALUE=DATE-TIME:20230522T130000Z DTEND;VALUE=DATE-TIME:20230522T140000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-237@indico.ift.uam-csic.es DESCRIPTION:Speakers: Mario Flory ()\nWe propose finite cutoff regions of holographic spacetimes as mapping between boundary states at different tim es and Wilsonian cutoffs. If the complexity of those quantum circuits is g iven by the gravitational action\, we are led to equations of motion for t he cutoff surface that obtain a particular geometric form\, where solution s are given in terms of surfaces with constant scalar curvature. This in t urn suggests a connection to the kinematic space program.\n\nhttps://indic o.ift.uam-csic.es/event/18/contributions/237/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/237/ END:VEVENT BEGIN:VEVENT SUMMARY:Lorentzian threads for generalized complexity DTSTART;VALUE=DATE-TIME:20230524T130000Z DTEND;VALUE=DATE-TIME:20230524T140000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-247@indico.ift.uam-csic.es DESCRIPTION:Speakers: Elena Cáceres ()\nIt was recently shown that the ma ximal-volume prescription for calculating holographic complexity (CV) is j ust one out of an infinite class of observables that display the required behavior to be the gravitational duals of complexity. This approach\, late r extended to include complexity-action\, has enlarged and changed our und erstanding of holographic complexity. Many questions arise in this new fra mework. In this talk\, I will present work in progress to understand how t his new class of generalized complexities is realized in the language of L orentzian threads.\n\nhttps://indico.ift.uam-csic.es/event/18/contribution s/247/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/247/ END:VEVENT BEGIN:VEVENT SUMMARY:Gravitation from optimized computation DTSTART;VALUE=DATE-TIME:20230524T100000Z DTEND;VALUE=DATE-TIME:20230524T110000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-246@indico.ift.uam-csic.es DESCRIPTION:Speakers: Andrew Svesko ()\nInspired by the universality of co mputation\, I advocate for a notion of spacetime complexity\, where gravit y arises as a consequence of spacetime optimizing the computational cost o f its own quantum dynamics. This principle is realized in the context of h olography\, where complexity is understood in terms of state preparation v ia Euclidean path integrals\, and the linearized equations of motion for a ny theory of gravity emerge from the first law of complexity. This suggest s gravity has a computational origin. When semi-classical bulk quantum cor rections are included\, the holographic first law is modified by an additi onal term which could be interpreted as `bulk complexity’. This leads to a derivation of semi-classical gravitational equations of motion.\n\nhttp s://indico.ift.uam-csic.es/event/18/contributions/246/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/246/ END:VEVENT BEGIN:VEVENT SUMMARY:Holographic Complexity Beyond Proposals and AdS Holography DTSTART;VALUE=DATE-TIME:20230524T083000Z DTEND;VALUE=DATE-TIME:20230524T093000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-245@indico.ift.uam-csic.es DESCRIPTION:Speakers: Michal Heller ()\nhttps://indico.ift.uam-csic.es/eve nt/18/contributions/245/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/245/ END:VEVENT BEGIN:VEVENT SUMMARY:Volume complexity of dS bubbles DTSTART;VALUE=DATE-TIME:20230523T130000Z DTEND;VALUE=DATE-TIME:20230523T140000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-243@indico.ift.uam-csic.es DESCRIPTION:Speakers: Roberto Auzzi ()\nHolographic volume complexity grow th in dS stretched horizon holography has a hyperfast behaviour\, which le ads to a divergence in a finite time. This is very different from AdS\, wh ere the complexity rate approaches a constant value. I'll discuss holograp hic volume complexity in a class of asymptotically AdS geometries with dS bubbles in their interior. With the exception of the static bubble case\, the complexity obtained from the volume of the smooth extremal surfaces wh ich are anchored just to the AdS boundary has a similar behaviour to the A dS case\, because it asymptotically grows linearly with time. The static b ubble configuration has a zero complexity rate and corresponds to a discon tinuous behaviour\, which resembles a first order phase transition. If ins tead we consider extremal surfaces which are anchored at both the AdS boun dary and the de Sitter stretched horizon\, we find that complexity growth is hyperfast\, as in the dS case.\n\nhttps://indico.ift.uam-csic.es/event/ 18/contributions/243/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/243/ END:VEVENT BEGIN:VEVENT SUMMARY:State dependence of Krylov complexity in 2d CFT DTSTART;VALUE=DATE-TIME:20230523T100000Z DTEND;VALUE=DATE-TIME:20230523T110000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-242@indico.ift.uam-csic.es DESCRIPTION:Speakers: Arnab Kundu ()\nWe compute the Krylov Complexity of a light operator O_L in an eigenstate of a 2d CFT at large central charge. The eigenstate corresponds to a primary operator O_H under the state-oper ator correspondence. We observe that the behaviour of K-complexity is diff erent (either bounded or exponential) depending on whether the scaling dim ension of O_H is below or above the critical dimension h_H=c/24\, marked b y the 1st order Hawking-Page phase transition point in the dual AdS_3 geom etry. Based on this feature\, we hypothesize that the notions of operator growth and K-complexity for primary operators in 2d CFTs are closely relat ed to the underlying entanglement structure of the state in which they are computed\, thereby demonstrating explicitly their state-dependent nature. To provide further evidence for our hypothesis\, we perform an analogous computation of K-complexity in a model of free massless scalar field theor y in 2d\, and in the integrable 2d Ising CFT\, where there is no such tran sition in the spectrum of states. We will also offer brief comments on ong oing works based on the above study.\n\nhttps://indico.ift.uam-csic.es/eve nt/18/contributions/242/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/242/ END:VEVENT BEGIN:VEVENT SUMMARY:Cost of holographic path integrals DTSTART;VALUE=DATE-TIME:20230522T143000Z DTEND;VALUE=DATE-TIME:20230522T153000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-238@indico.ift.uam-csic.es DESCRIPTION:Speakers: Andrew Rolph ()\nIn this talk\, I will introduce hol ographic proposals for computational cost. If complexity is the length of the shortest path between two states\, then cost is the length of a genera l\, not-necessarily-shortest path. To highlight the differences from the h olographic state complexity programme: (1) the boundary dual is cost\, the "off-shell" version of complexity\, (2) we consider all functions on all bulk subregions of any co-dimension (which satisfy the physical properties of cost)\, and (3) the proposals are by construction UV-finite. Lastly\, I will explain how the path integrals\, which we are proposing the cost of \, fit within the framework of holographic $T\\bar T$.\n\nhttps://indico.i ft.uam-csic.es/event/18/contributions/238/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/238/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantum Black Holes and Holographic Complexity DTSTART;VALUE=DATE-TIME:20230522T100000Z DTEND;VALUE=DATE-TIME:20230522T110000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-236@indico.ift.uam-csic.es DESCRIPTION:Speakers: Antonia Frassino ()\nIn this talk\, I will explore h ow quantum effects impact certain black holes and take into account their gravitational backreaction. Specifically\, I will delve into the descripti on of a quantum BTZ black hole (quBTZ). My discussion will include an anal ysis of the thermodynamic properties of these black holes. Additionally\, I will examine the various complexity proposals for the quBTZ and reveal t hat Action Complexity fails to account for the supplementary quantum contr ibutions and does not result in the correct classical limit. Conversely\, Volume Complexity allows for a consistent quantum expansion and aligns wit h established boundaries.\n\nhttps://indico.ift.uam-csic.es/event/18/contr ibutions/236/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/236/ END:VEVENT BEGIN:VEVENT SUMMARY:Integrability and complexity in quantum spin chains DTSTART;VALUE=DATE-TIME:20230522T083000Z DTEND;VALUE=DATE-TIME:20230522T093000Z DTSTAMP;VALUE=DATE-TIME:20260311T123932Z UID:indico-contribution-18-235@indico.ift.uam-csic.es DESCRIPTION:Speakers: Ben Craps ()\nThere is a widespread perception that dynamical evolution of integrable systems should be simpler in a quantifia ble sense than the evolution of generic systems\, though demonstrating thi s relation between integrability and reduced complexity in practice has re mained elusive. We provide a connection of this sort by constructing a spe cific matrix in terms of the eigenvectors of a given quantum Hamiltonian. The null eigenvalues of this matrix are in one-to-one correspondence with conserved quantities that have simple locality properties (a hallmark of i ntegrability). The typical magnitude of the eigenvalues\, on the other han d\, controls an explicit bound on Nielsen's complexity of the quantum evol ution operator\, defined in terms of the same locality specifications. We demonstrate how this connection works in a few concrete examples of quantu m spin chains that possess diverse arrays of highly structured conservatio n laws mandated by integrability.\n\nhttps://indico.ift.uam-csic.es/event/ 18/contributions/235/ LOCATION: URL:https://indico.ift.uam-csic.es/event/18/contributions/235/ END:VEVENT END:VCALENDAR