BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Vincent Van Hemelryck (KU Leuven) DTSTART:20211110T150000Z DTEND:20211110T160000Z DTSTAMP:20260404T131150Z UID:AnLy/1 DESCRIPTION:Title: Scale-separated AdS4 vacua of IIA orientifolds and M-theory\nby Vi ncent Van Hemelryck (KU Leuven) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nObtaining string compactifications where the KK sc ale is much higher than the cosmological constant scale is quite challengi ng. Such a separation of scales is however necessary for the theory to be genuinely lower-dimensional. In massive type IIA string theory there are s uch scale-separated vacua\, e.g. the DGKT AdS4 solutions. It has been show n recently that the classical orientifold backreaction in these vacua can be tuned small. In this talk\, I show that massless IIA on the other hand allows both weakly and strongly coupled AdS4 vacua that exhibit scale sepa ration and for which the backreaction can be tuned small as well. I will g ive evidence that the strongly coupled solutions can be lifted to scale se parated and sourceless (but classically singular) geometries in 11D superg ravity.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Giuseppe Dibitetto (Padua U.) DTSTART:20211124T150000Z DTEND:20211124T160000Z DTSTAMP:20260404T131150Z UID:AnLy/2 DESCRIPTION:Title: Non-perturbative instability of mIIA on AdS_4 x S^6\nby Giuseppe D ibitetto (Padua U.) as part of AnLy Strings and Fields online seminars\n\n \nAbstract\nI will start by reviewing the physics of KK bubbles and their higher-dimensional generalizations. Secondly\, I will move to discussing s lightly more general situations where the shrinking modulus is the string coupling. Subsequently\, I will focus on cases where a Freund-Rubin flux i s present\, thus leading to the necessity of introducing a source. Finally \, I will discuss the case of massive IIA on a 6-sphere as an explicit rea lization of the aforementioned mechanism and provide an appropriate physic al interpretation.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Ivonne Zavala (Swansea U.) DTSTART:20211208T150000Z DTEND:20211208T160000Z DTSTAMP:20260404T131150Z UID:AnLy/3 DESCRIPTION:Title: Multifield inflation in string theory and supergravity\nby Ivonne Zavala (Swansea U.) as part of AnLy Strings and Fields online seminars\n\n \nAbstract\nMultifield inflation arises naturally in supergravity and stri ng theory models. When several scalars are active during inflation\, the e ta-problem may be circumvented\, while new trajectories with large turns c an arise\, with interesting observational consequences. I will discuss th e prospects of realising these features in supergravity and string theory models of inflation.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Edgar Shaghoulian (Cornell U.) DTSTART:20220112T150000Z DTEND:20220112T160000Z DTSTAMP:20260404T131150Z UID:AnLy/4 DESCRIPTION:Title: The central dogma and cosmological horizons\nby Edgar Shaghoulian (Cornell U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstr act\nThe central dogma of black hole physics – which says that from the outside a black hole can be described in terms of a quantum system with ex p(Area/4G) states evolving unitarily – has recently been supported by co mputations indicating that the interior of the black hole is encoded in th e Hawking radiation of the exterior. In this paper\, we probe whether such a dogma for cosmological horizons has any support from similar computatio ns. The fact that the de Sitter bifurcation surface is a minimax surface ( instead of a maximin surface) causes problems with this interpretation whe n trying to import calculations analogous to the AdS case. This suggests a nchoring extremal surfaces to the horizon itself\, where we formulate a tw o-sided extremization prescription and find answers consistent with genera l expectations for a quantum theory of de Sitter space: vanishing total en tropy\, an entropy of A/4G when restricting to a single static patch\, an entropy of a subregion of the horizon which grows with the region size and threatens the central dogma until an island-like transition at half the h orizon size when the entanglement wedge becomes the entire static patch in terior\, and a de Sitter version of the Hartman-Maldacena transition.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Francesc Cunillera (U. Nottingham) DTSTART:20220209T150000Z DTEND:20220209T160000Z DTSTAMP:20260404T131150Z UID:AnLy/5 DESCRIPTION:Title: Quintessence and the Swampland: tales of parametric and numerical cont rol\nby Francesc Cunillera (U. Nottingham) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nWe provide a detailed discussion of the main theoretical and phenomenological challenges of quintessence mode l building in any parametric or numerically controlled regime of the modul i space of string theory. We argue that a working quintessence model requi res a leading order non-supersymmetric (near) Minkowski vacuum with an axi onic flat direction away from the boundary of moduli space. This axion\, w hen lifted by subdominant non-perturbative effects\, could drive hilltop q uintessence only for very tuned initial conditions and a very low inflatio nary scale.\nOur analysis has a twofold implication: (1) Scenarios which a re in agreement with the swampland dS conjecture\, like AdS and supersymme tric Minkowski vacua\, as well as runaways\, cannot allow for phenomenolog ically viable quintessence with full computational control. This raises do ubts on the validity of the swampland dS conjecture since it would imply a strong tension between quantum gravity and observations. (2) If data will prefer dynamical dark energy\, axion models based on misalignment mechani sms look more promising than hilltop scenarios which are very contrived.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Daniel Junghans (Harvard U.) DTSTART:20220302T150000Z DTEND:20220302T160000Z DTSTAMP:20260404T131150Z UID:AnLy/6 DESCRIPTION:Title: (Cancelled) Corrections to the LARGE-Volume Scenario\nby Daniel Ju nghans (Harvard U.) as part of AnLy Strings and Fields online seminars\n\n \nAbstract\nWe argue that de Sitter vacua in the LARGE-volume scenario of type IIB string theory are vulnerable to various unsuppressed curvature\, warping and g_s corrections. We discuss how these corrections affect the m oduli vevs\, the vacuum energy and the moduli masses. Our analysis reveals that the corrections are parametrically larger in the relevant expression s than one might have guessed from their suppression in the off-shell pote ntial. Some corrections appear without any parametric suppression at all\, which makes them particularly dangerous for candidate de Sitter vacua. Ot her types of corrections can in principle be made small for appropriate pa rameter choices. However\, we show in an explicit model that this is never possible for all corrections at the same time when the vacuum energy is p ositive.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Marios Petropoulos (Ecole Polytechnique\, CPHT) DTSTART:20220330T140000Z DTEND:20220330T150000Z DTSTAMP:20260404T131150Z UID:AnLy/7 DESCRIPTION:Title: Carrollian fluids and Chthonian versus celestial holography\nby Ma rios Petropoulos (Ecole Polytechnique\, CPHT) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nThe usual approach of fluid/gravity correspondence coincides with solving Einstein's equations in a generalize d "incomplete Newman-Unti gauge". In this framework\, the asymptotic symme try group is bigger and accounts for the boundary-fluid hydrodynamic frame invariance. The latter pattern holds both for Einstein and Ricci-flat spa cetimes\, dual to relativistic and Carrollian fluids\, respectively. This is a concrete starting point for approaching flat holography and understan ding the role of the BMS group on the dual boundary theory. It suggests th at the latter might be non-local in order to account for the infinite Chth onian degrees of freedom\, as opposed to the celestial proposal.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Joseph Conlon (Oxford U.) DTSTART:20220316T151500Z DTEND:20220316T161500Z DTSTAMP:20260404T131150Z UID:AnLy/8 DESCRIPTION:Title: Holographic Questions About Moduli Stabilisation\nby Joseph Conlon (Oxford U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstr act\nModuli stabilisation is an important and fundamental question in stri ng theory as it is a precursor to constructing semi-realistic string vacua . I describe work over the last few years aiming at examining moduli stabi lised vacua from a holographic perspective\, studying in particular LVS in IIB and DGKT in IIA. In scale separated limits of large volumes and weak coupling\, the conformal dimensions of dual operators approach fixed value s that are independent of fluxes and many other microscopic aspects of the constructions. A further intriguing property is the existence of integer conformal dimensions for DGKT vacua\, although the origin of these integer s is mysterious.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/8/ END:VEVENT BEGIN:VEVENT SUMMARY:Gianguido Dall'Agata (Padua U.) DTSTART:20220413T140000Z DTEND:20220413T150000Z DTSTAMP:20260404T131150Z UID:AnLy/9 DESCRIPTION:Title: Supergravity and the weak gravity conjecture\nby Gianguido Dall'Ag ata (Padua U.) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nI will show how the weak gravity conjecture applied to 4-dimensiona l supergravity theories can be very powerful in constraining which models can be realistically obtained as low-energy effective theories of string t heory. In particular\, I will discuss how we can obtain rather general and strong constraints on scale separation between the lower and higher dimen sional theory and how most models with positive energy critical points can not have a consistent string theory origin.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/9/ END:VEVENT BEGIN:VEVENT SUMMARY:Erik Plauschinn (Utrecht U.) DTSTART:20220511T140000Z DTEND:20220511T150000Z DTSTAMP:20260404T131150Z UID:AnLy/10 DESCRIPTION:Title: The tadpole conjecture in asymptotic limits\nby Erik Plauschinn ( Utrecht U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstra ct\nSuperstring theory is defined in ten space-time dimensions. In order t o connect it to physics in four dimensions one typically has to compactify the theory and satisfy a number consistency conditions. One of them is th e tadpole cancellation condition. Recently\, Bena\, Blabäck\, Grana\, and Lüst made a "tadpole conjecture" which - if true - would imply that many naively-allowed (flux-)compactifications are inconsistent. \nIn the first part of the talk I will explain and illustrate the tadpole conjecture. In the second part I present arguments towards a proof of the conjecture in asymptotic limits using the framework of asymptotic Hodge theory.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/10/ END:VEVENT BEGIN:VEVENT SUMMARY:Romain Ruzziconi (TU Wien) DTSTART:20220525T140000Z DTEND:20220525T150000Z DTSTAMP:20260404T131150Z UID:AnLy/11 DESCRIPTION:Title: A Carrollian Perspective on Celestial Holography\nby Romain Ruzzi coni (TU Wien) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nI will present a holographic description of gravity in 4d asymptoti cally flat spacetime in terms of a 3d sourced conformal Carrollian field t heory. The external sources encode the leaks of gravitational radiation at null infinity. The Ward identities of this theory are shown to reproduce those of the 2d celestial CFT after relating Carrollian to celestial opera tors. This suggests a new set of interplays between gravity in asymptotica lly flat spacetime\, sourced conformal Carrollian field theory and celesti al CFT. \n\n\nBased on: https://arxiv.org/abs/2202.04702\n LOCATION:https://stable.researchseminars.org/talk/AnLy/11/ END:VEVENT BEGIN:VEVENT SUMMARY:Michela Petrini (LPTHE Paris) DTSTART:20220608T140000Z DTEND:20220608T150000Z DTSTAMP:20260404T131150Z UID:AnLy/12 DESCRIPTION:Title: A systematic approach to consistent truncations\nby Michela Petri ni (LPTHE Paris) as part of AnLy Strings and Fields online seminars\n\n\nA bstract\nIn this talk I will discuss how generalised geometry provides a s ystematic way to construct and classify consistent truncations to differen t dimensions and with different amount of supersymmetry. As an example I w ill apply this formalism to the classification of N=2 gauged supergravity in 5 five dimensions that can be obtained as consistent truncations of typ e IIB or M theory.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/12/ END:VEVENT BEGIN:VEVENT SUMMARY:Oscar Loaiza-Brito (Guanajuato U.) DTSTART:20220622T140000Z DTEND:20220622T150000Z DTSTAMP:20260404T131150Z UID:AnLy/13 DESCRIPTION:Title: AdS and dS vacua from torsion and non-BPS states\nby Oscar Loaiza -Brito (Guanajuato U.) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nWe look for minimal conditions to construct stable Anti de Sitter and de Sitter vacua from type IIB String theory compactification on Kähler manifolds with torsion in the presence of O3-planes. This allows contributions to the scalar potential from the five-form flux and from D5- branes wrapping torsional cycles -interpreted as non-BPS states carrying d iscrete Z_2 charge and classified by K-theory- which in turn leads to the construction of AdS and dS vacua respectively. We shall discuss some const raints on the configuration as well as possible sources of instabilities.\ n LOCATION:https://stable.researchseminars.org/talk/AnLy/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Claude Duhr (Bonn U.) DTSTART:20221005T140000Z DTEND:20221005T150000Z DTSTAMP:20260404T131150Z UID:AnLy/14 DESCRIPTION:Title: 2D fishnet integrals and Calabi-Yau geometries\nby Claude Duhr (B onn U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\n We argue that Yangian-invariant l-loop fishnet integrals in 2 dimensions a re closely related to a family of Calabi-Yau l-folds. This allows us to re duce the computation of these integrals to the computation of the Calabi-Y au periods. The periods are solutions of the Picard-Fuchs differential equ ations\, which in turn are determined by the Yangian symmetry. Finally\, we show that the values of these fishnet integrals admit a natural interpr etation as the quantum volume of the Calabi-Yau.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/14/ END:VEVENT BEGIN:VEVENT SUMMARY:Jean-Luc Lehners (Postdam\, MPI) DTSTART:20221019T140000Z DTEND:20221019T150000Z DTSTAMP:20260404T131150Z UID:AnLy/15 DESCRIPTION:Title: How to create universes with internal flux\nby Jean-Luc Lehners ( Postdam\, MPI) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nString compactifications typically require fluxes\, for example in order to stabilise moduli. Such fluxes\, when they thread internal dimensi ons\, are topological in nature and take on quantised values. This poses t he puzzle as to how they could arise in the early universe\, as they canno t be turned on incrementally. Working with string inspired models in 6 and 8 dimensions\, we show that there exist no-boundary solutions in which in ternal fluxes are present from the creation of the universe onwards. The n o-boundary proposal can thus explain the origin of fluxes in a Kaluza-Klei n context. In fact\, it acts as a selection principle since no-boundary so lutions are only found to exist when the fluxes have the right magnitude t o lead to an effective potential that is positive and flat enough for acce lerated expansion. Within the range of selected fluxes\, the no-boundary w ave function assigns higher probability to smaller values of flux. Our mod els illustrate how cosmology can act as a filter on a landscape of possibl e higher-dimensional solutions.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/15/ END:VEVENT BEGIN:VEVENT SUMMARY:Shai Chester (Weizmann Inst.) DTSTART:20221109T150000Z DTEND:20221109T160000Z DTSTAMP:20260404T131150Z UID:AnLy/16 DESCRIPTION:Title: Pure supergravity and the conformal bootstrap\nby Shai Chester (W eizmann Inst.) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nWe consider graviton scattering in maximal supergravity on Anti-de Sitter space (AdS) in d+1 dimensions for d=3\, 4\, and 6 with no extra com pact spacetime factor. Holography suggests that this theory is dual to an exotic maximally supersymmetric conformal field theory (CFT) in d dimensio ns whose only light single trace operator is the stress tensor. This contr asts with more standard cases like Type IIB string theory on AdS_5x S^5 du al to N=4 Super-Yang-Mills\, where the CFT has light single trace operator s for each Kaluza-Klein mode on S^5. We compute the 1-loop correction to t he pure AdS_{d+1} theory in a small Planck length expansion\, which is dua l to the large central charge expansion in the CFT. We find that this corr ection saturates the most general non-perturbative conformal bootstrap bou nds on this correlator in the large central charge regime for d=3\, 4\, 6. After imposing theory-specific constraints from localization in d=3\, 4\, the bootstrap constraints strengthen and are then saturated by the string /M-theory dual CFT data.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/16/ END:VEVENT BEGIN:VEVENT SUMMARY:Bruno Valeixo Bento (U. Liverpool (main)) DTSTART:20221123T150000Z DTEND:20221123T160000Z DTSTAMP:20260404T131150Z UID:AnLy/17 DESCRIPTION:Title: Gravity at the Tip of the Throat\nby Bruno Valeixo Bento (U. Live rpool (main)) as part of AnLy Strings and Fields online seminars\n\n\nAbst ract\nWarped throats have been used in countless works in the context of s tring theory compactifications\, in particular for their ability to suppre ss high energy scales. I will focus on the gravitational sector of the res ulting 4d EFT\, with its tower of Kaluza-Klein (KK) gravitons. By assuming that we live on a (3+1)-dimensional brane within the throat\, we can stud y how the warping influences the effects of this tower – in particular\, I will show how the tower corrects the Newtonian potential and discuss ho w gravitational experiments and observations may be used to test the possi bility that our Universe corresponds to a brane living in a warped throat. I will also briefly mention what this means for gravitational wave signa tures originating from different types of sources within this setup.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/17/ END:VEVENT BEGIN:VEVENT SUMMARY:Thomas Van Riet (Leuven U.) DTSTART:20221214T150000Z DTEND:20221214T160000Z DTSTAMP:20260404T131150Z UID:AnLy/18 DESCRIPTION:Title: A supergravity view on a possible AdS1/CFT0 correspondence\nby Th omas Van Riet (Leuven U.) as part of AnLy Strings and Fields online semina rs\n\n\nAbstract\nTop down holography relies on a decoupling limit of clos ed and open strings near the horizon of a stack of D branes. The simplest such horizon geometries are of the form of an AdS space times a sphere tim es a torus with the total product space being a 10 or 11-dimensional solut ion of supergravity. I will explain that this picture naturally leads one to consider an extreme case which would be AdS1 x S1 x T9 and it would ori ginate from a brane bound state given by the so-called D7 -D instanton sys tem\, which is not fully understood in supergravity. I will point out that the dual matrix model seems already written down in the literature before and it is an extension of the IKKT matrix model. I will attempt to be ped agogical and the talk will mostly reflect the supergravity side of the pro blem.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/18/ END:VEVENT BEGIN:VEVENT SUMMARY:Eduardo Gonzalo-Badia (Lehigh U.) DTSTART:20230111T150000Z DTEND:20230111T160000Z DTSTAMP:20260404T131150Z UID:AnLy/19 DESCRIPTION:Title: Type IIB flux compactifications with h^{1\,1} = 0\nby Eduardo Gon zalo-Badia (Lehigh U.) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nType IIB flux vacua based on Landau-Ginzburg models without Kähler deformations provide fully-controlled insights into the non-geome tric and strongly-coupled string landscape. We show here that supersymmetr ic flux configurations at the Fermat point of the 1^9 model\, which were f ound long-time ago to saturate the orientifold tadpole\, leave a number of massless fields\, which however are not all flat directions of the superp otential at higher order. More generally\, the rank of the Hessian of the superpotential is compatible with a suitably formulated tadpole conjecture for all fluxes that we found. Moreover\, we describe new infinite familie s of supersymmetric 4d N = 1 Minkowski and AdS vacua and confront them wit h several other swampland conjectures.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/19/ END:VEVENT BEGIN:VEVENT SUMMARY:Junho Hong (KU Leuven) DTSTART:20230125T150000Z DTEND:20230125T160000Z DTSTAMP:20260404T131150Z UID:AnLy/20 DESCRIPTION:Title: Large N partition functions\, holography\, and black holes\nby Ju nho Hong (KU Leuven) as part of AnLy Strings and Fields online seminars\n\ n\nAbstract\nIn this talk\, I will present a simple closed form expression for the topologically twisted index of the ABJM theory as a function of t he magnetic fluxes and complexified electric chemical potentials valid at fixed k and to all orders in the large N expansion. These results have imp ortant implications for holography and the microscopic entropy counting of supersymmetric static AdS4 black holes. I will also discuss the squashed sphere partition function and the superconformal index of the ABJM theory in a similar context. Finally\, I will briefly comment on the generalizati on to other N = 2 superconformal field theories.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/20/ END:VEVENT BEGIN:VEVENT SUMMARY:T. Grimm (Utrecht U.) DTSTART:20230222T150000Z DTEND:20230222T160000Z DTSTAMP:20260404T131150Z UID:AnLy/21 DESCRIPTION:Title: The Tameness of Quantum Field Theory\nby T. Grimm (Utrecht U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nIn this ta lk I will introduce a generalized notion of finiteness and argue that it a ppears in quantum field theories and in all well-understood string theory effective theories. The underlying mathematical foundation is described by the tame geometry that is built from o-minimal structures introduced in m athematical logic. For renormalizable quantum field theories\, I will give a general proof that amplitudes at each order in the loop expansion are t ame functions. I will discuss several exact non-perturbative results and s how that they are tame but only given constraints on the UV definition of the theory. I will present new evidence that tameness is linked to a consi stent coupling to quantum gravity. Motivated by these insights\, I will su ggest that sets of consistent physical theories and their observables can be used to define tame structures. I will make concrete conjectures how th is is implemented for conformal field theories and comment on some of the implications.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/21/ END:VEVENT BEGIN:VEVENT SUMMARY:Yixuan Li (Munich\, Max Planck Inst.) DTSTART:20230308T150000Z DTEND:20230308T160000Z DTSTAMP:20260404T131150Z UID:AnLy/22 DESCRIPTION:Title: Local supersymmetry enhancement and the entropy of three-charge black holes\nby Yixuan Li (Munich\, Max Planck Inst.) as part of AnLy Strin gs and Fields online seminars\n\n\nAbstract\nIn string theory\, black hole s can be realised as bound states of branes and strings. The branes and th e strings preserve a set of global supersymmetries\, which imposes the geo metry of the near-horizon region. However\, there exists a whole moduli sp ace of brane systems that preserve those same global supersymmetries\, but whose number of local supersymmetries is enhanced. Such brane configurati on should describe some microstates of the black hole\; but how much of th e black-hole entropy can these configurations account for? \n\nIn this tal k\, I will first present this formalism based on local supersymmetries tha t identifies the ingredients needed to describe the microstates of a super symmetric black hole.\nThen\, I will illustrate the local supersymmetry en hancement mechanism with the three-charge F1-NS5-P black hole in Type IIA. The black-hole entropy is accounted by the fractionation\, due to the pre sence of the five-branes\, of the fundamental strings into many ‘little strings’ which act as independent momentum carriers.\nI will apply the s upersymmetric enhancement mechanism to these brane systems\, and show it g ives rise to a new class of black-hole microstate solutions which preserve the rotational symmetry of the black-hole horizon. Finally\, I will expla in why one could expect their supergravity description to be horizonless i n the M-theory frame\, and how our results point towards a change of strat egy in the fuzzball programme in the endeavour of constructing horizonless black-hole microstates.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/22/ END:VEVENT BEGIN:VEVENT SUMMARY:Luca Ciambelli (Perimeter Institute) DTSTART:20230322T150000Z DTEND:20230322T160000Z DTSTAMP:20260404T131150Z UID:AnLy/23 DESCRIPTION:Title: Corner Symmetries in Gravity\nby Luca Ciambelli (Perimeter Instit ute) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nIn the last 7 years\, we have gathered a lot of results pointing toward an un derlying universal symmetry structure in gravity. I will give an overview of these recent results\, focussing in particular on two main features. Fi rst\, we will derive the universal corner symmetry algebra\, which can be regarded as the algebra of observables in classical gravity. Secondly\, we will propose an extension of the gravitational covariant phase space such that all diffeomorphism charges are integrable\, albeit the system is sti ll dissipative. These two ingredients are at the core of the corner propos al\, which is a bottom-up approach to quantum gravity\, based on symmetrie s. After enunciating and discussing this proposal\, time permitting\, I wi ll mention how the geometric degrees of freedom at cuts of null hypersurfa ces can be quantized\, and its far-reaching consequences for quantum gravi ty.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/23/ END:VEVENT BEGIN:VEVENT SUMMARY:Sebastian Mizera (Princeton\, Inst. Advanced Study) DTSTART:20230405T140000Z DTEND:20230405T150000Z DTSTAMP:20260404T131150Z UID:AnLy/24 DESCRIPTION:Title: Evaluating one-loop string amplitudes\nby Sebastian Mizera (Princ eton\, Inst. Advanced Study) as part of AnLy Strings and Fields online sem inars\n\n\nAbstract\nScattering amplitudes in string theory are written as formal integrals of correlations functions over the moduli space of punct ured Riemann surfaces. It's well-known\, albeit not often emphasized\, tha t this prescription is only approximately correct because of the ambiguiti es in defining the integration domain. In this talk\, we propose a resolut ion of this problem for one-loop open-string amplitudes and present their first evaluation at finite energy and scattering angle. Our method involve s a deformation of the integration contour over the modular parameter to a fractal contour introduced by Rademacher in the context of analytic numbe r theory. This procedure leads to explicit and practical formulas for the one-loop planar and non-planar type-I superstring four-point amplitudes\, amenable to numerical evaluation. We plot the amplitudes as a function of the Mandelstam invariants and directly verify long-standing conjectures ab out their behavior at high energies.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/24/ END:VEVENT BEGIN:VEVENT SUMMARY:Max Wiesner (Harvard U.\, CMSA) DTSTART:20230503T140000Z DTEND:20230503T150000Z DTSTAMP:20260404T131150Z UID:AnLy/25 DESCRIPTION:Title: Bounds on Species Scale and the Distance Conjecture\nby Max Wiesn er (Harvard U.\, CMSA) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nThe species scale serves as a UV cutoff in the gravitationa l sector of an EFT and can depend on the moduli of the theory as the spect rum of the theory varies. We argue that the slope of the species scale as a function of massless (or light) modes is bounded by an O(1) coefficient. This bound is true at all points in moduli space including also its inter ior. The argument is based on the idea that the short distance contributio n of massless modes to gravitational terms in the EFT cannot dramatically affect the black hole entropy. Based on string theory arguments we expect the O(1) constant in this bound to be equal to 1/d-2 as we approach the bo undary of the moduli space. However\, we find that the slope of the specie s scale can approach its asymptotic value from above as we go from interio r points to the boundaries\, thereby implying that the constant in the bou nd must be larger than 1/d-2. The bound on the variation of the species sc ale also implies that the mass of towers of light modes cannot go to zero faster than exponential in field distance in accordance with the Distance Conjecture.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/25/ END:VEVENT BEGIN:VEVENT SUMMARY:Lorenz Eberhardt (IAS\, Princeton) DTSTART:20230531T140000Z DTEND:20230531T150000Z DTSTAMP:20260404T131150Z UID:AnLy/26 DESCRIPTION:Title: Solving 3d Gravity with Virasoro TQFT\nby Lorenz Eberhardt (IAS\, Princeton) as part of AnLy Strings and Fields online seminars\n\n\nAbstra ct\nI will explain a proposal which relates three-dimensional quantum grav ity in AdS3 to a particular 3d TQFT that we refer to as ``Virasoro TQFT''. This relation gives a precise meaning to the standard folklore that pure 3d gravity is related to two copies of SL(2\,R) Chern-Simons theory. I wil l discuss that replacing SL(2\,R) Chern-Simons theory by Virasoro TQFT sol ves several known problems in the correspondence. The relation provides a computationally useful tool to study partition functions of 3d gravity. Th e talk is based o\n LOCATION:https://stable.researchseminars.org/talk/AnLy/26/ END:VEVENT BEGIN:VEVENT SUMMARY:Gerben Venken (University of Heidelberg\, ITP) DTSTART:20230517T140000Z DTEND:20230517T150000Z DTSTAMP:20260404T131150Z UID:AnLy/27 DESCRIPTION:Title: The impact of alpha' corrections on de Sitter uplifts and warped thro ats\nby Gerben Venken (University of Heidelberg\, ITP) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nOne of the most often-u sed proposals for constructing a de Sitter vacuum in string theory is by u plifting using a puffed-up anti-D3 brane in a warped throat as done in KKL T and LVS. In recent years there has been much discussion about the validi ty and control of such constructions\; more broadly\, the question of whet her one can obtain controlled de Sitter vacua at all in string theory has come under close scrutiny. In this talk I will consider puffed-up antibran es in a warped throat and discuss the impact of alpha' corrections to the puffed-up brane worldvolume theory on the dynamics of the brane (specific ally the KPV process)\, what control one has over such corrections and whe ther such correction pose an obstruction to a de Sitter uplift or are actu ally a blessing in disguise. Based on arXiv:2212.07437.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/27/ END:VEVENT BEGIN:VEVENT SUMMARY:Manki Kim (MIT\, Cambridge\, CTP) DTSTART:20230628T140000Z DTEND:20230628T150000Z DTSTAMP:20260404T131150Z UID:AnLy/28 DESCRIPTION:Title: Towards string loop corrections in Calabi-Yau orientifold compactific ations\nby Manki Kim (MIT\, Cambridge\, CTP) as part of AnLy Strings a nd Fields online seminars\n\n\nAbstract\nComputation of string loop correc tions to the effective action has been one of the main challenges in strin g phenomenology. One major complication for such computations is that the string loop corrections are sensitive to the spectrum of strings probing C alabi-Yau orientifolds\, which is practically inaccessible. In this talk\, I will claim that some terms in the string one loop corrections to the Ka hler potential are computed by more computable crude details of the string spectrum. This result may pave a way to explicit computations of the stri ng loop corrections in generic Calabi-Yau orientifold compactifications.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/28/ END:VEVENT BEGIN:VEVENT SUMMARY:Jerome Quintin (U. Waterloo\, Perimeter Inst.) DTSTART:20231004T140000Z DTEND:20231004T150000Z DTSTAMP:20260404T131150Z UID:AnLy/29 DESCRIPTION:Title: Applications of the Kontsevich-Segal Bound in Quantum Cosmology\n by Jerome Quintin (U. Waterloo\, Perimeter Inst.) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nKontsevich and Segal have propos ed a constraint on complex metrics by demanding the path integral of p-for m fields to converge on a given fixed background. Witten has conjectured t hat this constraint could apply to quantum gravity path integrals. The con sequences for quantum cosmology have thus been explored in the last couple of years. I will review some of these recent developments\, including cla ssical and quantum (tunnelling) transitions of the universe. Emphasis will be given on the Hartle-Hawking no-boundary proposal\, where it is found t hat flatter potentials more easily satisfy the Kontsevich-Segal bound. Whe n taking into account the weighting of the wave function\, which favours n ucleation at low values on the inflationary potential\, the effects conspi re to suggest that only a minimal amount of inflation could have occurred. This\, in turn\, points towards our universe today being relatively small .\n LOCATION:https://stable.researchseminars.org/talk/AnLy/29/ END:VEVENT BEGIN:VEVENT SUMMARY:Victor Rodriguez (Princeton U.) DTSTART:20231018T140000Z DTEND:20231018T150000Z DTSTAMP:20260404T131150Z UID:AnLy/30 DESCRIPTION:Title: The Virasoro minimal string and 2d string cosmology\nby Victor Ro driguez (Princeton U.) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nI will introduce a new critical string theory in two dimens ions and explain that this theory\, viewed as two-dimensional quantum grav ity on the worldsheet\, is equivalent to a double-scaled matrix integral. The worldsheet theory consists of Liouville CFT coupled to timelike Liouvi lle CFT. The double-scaled matrix integral has as its leading density of s tates the universal Cardy density of primaries in a two-dimensional CFT of central charge c\, thus motivating the name Virasoro minimal string. The duality holds for any value of the continuous parameter c and reduces to t he JT gravity/matrix integral duality in the large central charge limit\, providing a precise stringy realization of JT gravity. From a target space time point of view\, I will describe how this theory may be viewed as a co smological background in two dimensions.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/30/ END:VEVENT BEGIN:VEVENT SUMMARY:Andrea Campoleoni (U. Mons) DTSTART:20231108T150000Z DTEND:20231108T160000Z DTSTAMP:20260404T131150Z UID:AnLy/31 DESCRIPTION:Title: Flat from anti-de Sitter\nby Andrea Campoleoni (U. Mons) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nThe space of sol utions of Einstein's equations is severely altered by the presence of a co smological constant. This is manifest when solving the equations of motion close to the boundary of spacetime. In AdS all information about the solu tions in encoded a metric and an energy-momentum tensor defined on the tim e-like boundary. On the other hand\, at null infinity the information abou t the solutions is encoded in an infinite number of functions\, satisfying suitable flux-balance laws. In spite of these striking differences\, we s how how the space of Ricci-flat manifolds can be recovered from that of Ei nstein spaces by expanding the AdS boundary energy-momentum in powers of t he cosmological constant. In this process\, the flux-balance laws are also recovered by demanding that the line element remains finite in the limit of vanishing cosmological constant. The analysis is performed in a modifie d version of the Newman-Unti gauge\, that has the additional advantage of naturally disclosing the Carrollian structures emerging at null infinity.\ n LOCATION:https://stable.researchseminars.org/talk/AnLy/31/ END:VEVENT BEGIN:VEVENT SUMMARY:Matthew Kleban (New York U.\, CCPP) DTSTART:20231122T150000Z DTEND:20231122T160000Z DTSTAMP:20260404T131150Z UID:AnLy/32 DESCRIPTION:Title: Axion Landscapes in Cosmology and String Theory\nby Matthew Kleba n (New York U.\, CCPP) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nI will review axion landscapes in cosmology and explain the ir potential for explaining many of the large-scale features of our univer se\, including the big bang\, inflation\, dark matter\, and dark energy. These explanations can be successful when there are O(100s) of axion field s with random scales and a random charge matrix that is not too sparse. T urning to string theory\, I will describe recent work which numerically sa mpled the landscape of axions potentials in Calabi-Yau compactifications o f type IIB. While many of these compactifications admit hundreds of axion s\, correlations between the scales and charges result in a meager landsca pe with few unique minima in any given compactification. These results in dicate that explaining these features of our universe may require a more g eneral landscape with varying topology or flux.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/32/ END:VEVENT BEGIN:VEVENT SUMMARY:Nat Levine (ENS\, Paris\, IPM) DTSTART:20231129T150000Z DTEND:20231129T160000Z DTSTAMP:20260404T131150Z UID:AnLy/33 DESCRIPTION:Title: Equivalence of 1-loop RG flows in 4d Chern-Simons and integrable 2d s igma-models\nby Nat Levine (ENS\, Paris\, IPM) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nCostello\, Witten and Yamazaki proposed a 4d Chern-Simons theory as a unified way to engineer integrable models. In the presence of 'Disorder' defects (for non-ultralocal 2d theor ies)\, this correspondence has been established only classically. As a fir st quantum check\, I will derive the matching of 1-loop divergences betwee n the 4d and 2d theories. This study will uncover a simple\, 'universal' s tructure for the divergences in the 2d theory. My assumptions are general and seem to isolate sigma-models among the 2d theories. (Based on 2309.16 753)\n LOCATION:https://stable.researchseminars.org/talk/AnLy/33/ END:VEVENT BEGIN:VEVENT SUMMARY:Gianluca Inverso (INFN\, Padua) DTSTART:20231213T150000Z DTEND:20231213T160000Z DTSTAMP:20260404T131150Z UID:AnLy/34 DESCRIPTION:Title: 2d gauged maximal supergravities and Kaluza–Klein reductions\nb y Gianluca Inverso (INFN\, Padua) as part of AnLy Strings and Fields onlin e seminars\n\n\nAbstract\nI will summarise the general framework of consis tent Kaluza–Klein truncations from D=11 and type II supergravities to ga uged maximal supergravities in two dimensions. This makes it possible to d escribe the complete bosonic dynamics of all D=2 gauged maximal supergravi ties that admit a geometric uplift.\nThe construction can be applied in pa rticular to prove and construct the consistent truncation of eleven-dimens ional supergravity on S8×S1 to D=2 SO(9) gauged supergravity\, relevant f or the holographic description of the M-theory/BFSS matrix model.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/34/ END:VEVENT BEGIN:VEVENT SUMMARY:Gwenael Ferrando (IPht\, Saclay) DTSTART:20231220T150000Z DTEND:20231220T160000Z DTSTAMP:20260404T131150Z UID:AnLy/35 DESCRIPTION:Title: A Large Twist Limit for Any Operator in N=4 SYM\nby Gwenael Ferra ndo (IPht\, Saclay) as part of AnLy Strings and Fields online seminars\n\n \nAbstract\nThe fishnet theory was obtained as a strongly twisted\, weakly coupled limit of N=4 SYM. Though still non-trivial\, it is much simpler t han the original N=4 SYM theory. The appearance of integrability is better understood\, and the holographic dual was constructed from first principl es. Both can be tied to the existence of an iterative structure for some o f the correlators. However\, most of the operators of the original theory are now protected. We argue that it is possible to devise a double-scaling limit for any single-trace operator in N=4 SYM. Generically\, this involv es some type of mixing with other operators. We also prove integrability f or all the examples that we study. This work opens the door to a systemati c expansion of N=4 SYM around the large-twist limit.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/35/ END:VEVENT BEGIN:VEVENT SUMMARY:Fernando Marchesano (IFT\, Madrid) DTSTART:20240207T150000Z DTEND:20240207T160000Z DTSTAMP:20260404T131150Z UID:AnLy/37 DESCRIPTION:Title: On the moduli space curvature at infinity\nby Fernando Marchesano (IFT\, Madrid) as part of AnLy Strings and Fields online seminars\n\n\nAb stract\nWe analyse the scalar curvature of the vector multiplet moduli spa ce M(VM\,X) of type IIA string theory compactified on a Calabi--Yau manifo ld X. While the volume of M(VM\,X) is known to be finite\, cases have been found where the scalar curvature diverges positively along trajectories o f infinite distance. We classify the asymptotic behaviour of the scalar cu rvature for all large volume limits within M(VM\,X)\, for any choice of X\ , and provide the source of the divergence both in geometric and physical terms. Geometrically\, there are effective divisors whose volumes do not v ary along the limit. Physically\, the EFT subsector associated to such div isors is decoupled from gravity along the limit\, and defines a rigid N=2 field theory with a non-vanishing moduli space curvature $R_{rigid}$. We p ropose that the relation between scalar curvature divergences and field th eories that can be decoupled from gravity is a common trait of moduli spac es compatible with quantum gravity.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/37/ END:VEVENT BEGIN:VEVENT SUMMARY:Vincent Menet (Paris\, LPTHE) DTSTART:20240117T150000Z DTEND:20240117T160000Z DTSTAMP:20260404T131150Z UID:AnLy/38 DESCRIPTION:Title: New non-supersymmetric flux vacua from generalised calibrations\n by Vincent Menet (Paris\, LPTHE) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nWe construct a new class of non-supersymmetric te n-dimensional type II flux vacua\, by studying first order differential eq uations which are deformations of the N=1 supersymmetry conditions. We do so within the context of Generalised Complex Geometry\, where there is a n atural interpretation of the N = 1 supersymmetry conditions in terms of ca libration conditions for probe D-branes\, called D-string\, domain-wall or space-filling branes\, depending on them wrapping 2\, 3 or 4 non-compact dimensions. We focus on a subclass of non-supersymmetric vacua violating t he D-string calibration condition\, where the deformation of the calibrati on condition is dictated by the foliated geometry of the internal space. W e present the explicit construction of an example SU(3) background.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/38/ END:VEVENT BEGIN:VEVENT SUMMARY:Karapet Mkrtchyan (Imperial College London) DTSTART:20240214T150000Z DTEND:20240214T160000Z DTSTAMP:20260404T131150Z UID:AnLy/39 DESCRIPTION:Title: Democratic formulation for p-forms and non-linear (twisted) self-dual ity equation\nby Karapet Mkrtchyan (Imperial College London) as part o f AnLy Strings and Fields online seminars\n\n\nAbstract\nI will summarize recent progress in the democratic covariant Lagrangian formulation of (chi ral) p-form dynamics\, including arbitrary abelian interactions and deriva tion of these Lagrangians from the description as edge modes of topologica l theories in higher dimensions.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/39/ END:VEVENT BEGIN:VEVENT SUMMARY:Cristofero Fraser-Taliente (Oxford U.\, Theor. Phys.) DTSTART:20240306T150000Z DTEND:20240306T160000Z DTSTAMP:20260404T131150Z UID:AnLy/40 DESCRIPTION:Title: Computation of Quark Masses in String Theory\nby Cristofero Frase r-Taliente (Oxford U.\, Theor. Phys.) as part of AnLy Strings and Fields o nline seminars\n\n\nAbstract\nWe present a numerical computation\, based o n neural network techniques\, of the physical Yukawa couplings in a hetero tic string theory model obtained by compactifying on a smooth Calabi-Yau t hreefold. The model in question is one of a large class of heterotic line bundle models with precisely the MSSM low-energy spectrum plus fields unch arged under the standard-model group. The relevant quantities\, that is\, the Ricci-flat Calabi-Yau metric\, the Hermitian Yang-Mills bundle metrics and the harmonic bundle-valued forms\, are all computed by training suita ble neural networks. The calculation is carried out at several points alon g one-parameter family in complex structure moduli space\, and each comple te calculation takes about half a day on a laptop. The methods presented h ere generalise to other string models and constructions\, including to F-t heory models.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/40/ END:VEVENT BEGIN:VEVENT SUMMARY:Benjamin J. Heindenreich (UMass Amherst) DTSTART:20240403T140000Z DTEND:20240403T150000Z DTSTAMP:20260404T131150Z UID:AnLy/41 DESCRIPTION:Title: A Proof of the Weak Gravity Conjecture in Perturbative Bosonic String Theory\nby Benjamin J. Heindenreich (UMass Amherst) as part of AnLy S trings and Fields online seminars\n\n\nAbstract\nI present a complete proo f of the Weak Gravity Conjecture (WGC) in perturbative\, bosonic string th eory\, completing several partial arguments given in past literature. The proof leverages modular invariance\, long-range forces\, and their connect ion to extremal black holes. Along the way\, I discuss several variants of the WGC that play a role in the proof. I conclude by previewing the exten sion of the proof to perturbative superstrings\, which is work in progress .\n LOCATION:https://stable.researchseminars.org/talk/AnLy/41/ END:VEVENT BEGIN:VEVENT SUMMARY:Arthur Hebecker (University of Heidelberg) DTSTART:20240515T140000Z DTEND:20240515T150000Z DTSTAMP:20260404T131150Z UID:AnLy/42 DESCRIPTION:Title: Loop Blowup Inflation\nby Arthur Hebecker (University of Heidelbe rg) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nI wi ll discuss a new\, simple model of inflation in string theory. The role of the inflaton is played by a blowup modulus of a type IIB Calabi-Yau compa ctification. I will start by recalling that\, in the Large Volume Scenario of moduli stabilization\, such a modulus can remain unstabilized at leadi ng order. This observation has given rise to the proposal of Blowup Inflat ion. However\, as I will explain\, loop corrections are generically presen t and too large to allow for slow roll. Our proposal employs this setting in a new regime\, where the value of the blowup modulus is much larger and slow-roll can hence be realized. A detailed analysis\, based on the expli citly known form of loop corrections in this specific geometry\, reveals t hat observational and consistency constraints can be met and interesting p redictions for inflationary and late-time cosmological observables are pos sible.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/42/ END:VEVENT BEGIN:VEVENT SUMMARY:Shota Komatsu (CERN) DTSTART:20240612T140000Z DTEND:20240612T150000Z DTSTAMP:20260404T131150Z UID:AnLy/43 DESCRIPTION:Title: BMN matrix model and open-closed-open triality\nby Shota Komatsu (CERN) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nW e revisit the Berenstein-Maldacena-Nastase (BMN) conjecture relating M-the ory on a PP-wave background and Matrix Quantum Mechanics (MQM) of N×N mat rices. In particular\, we study the BMN MQM at strong coupling and finite N and derive an effective Hamiltonian that describes non-relativistic free particles in a harmonic trap. The energy spectrum predicted by this Hamil tonian matches the supergravity excitation spectrum around the PP-wave bac kground\, if we further assume the existence of bound states. Our derivati on is based on the strong coupling expansion of the wavefunction and super sedes the naive path integral approach that can lead to incorrect results\ , as we demonstrate in a simple toy model. We conclude by discussing the r elation between the BMN conjecture and AdS${}_4$/CFT${}_3$.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/43/ END:VEVENT BEGIN:VEVENT SUMMARY:Chris Blair (Madrid\, IFT) DTSTART:20240619T140000Z DTEND:20240619T150000Z DTSTAMP:20260404T131150Z UID:AnLy/44 DESCRIPTION:Title: Unification of Decoupling Limits in String and M-Theory\nby Chris Blair (Madrid\, IFT) as part of AnLy Strings and Fields online seminars\n \n\nAbstract\nOur understanding of M-theory is based on a duality web conn ecting different limits of the theory. I'll discuss the extension of this duality web to a wide variety of decoupling limits related by duality to t he null reduction of M-theory (and hence to the proposal that M-theory can be described by Matrix theory). From a modern perspective\, these limits involve non-Lorentzian geometries. I'll discuss how to systematically expl ore these corners of M-theory\, following the roadmap of https://arxiv.org /abs/2311.10564\n LOCATION:https://stable.researchseminars.org/talk/AnLy/44/ END:VEVENT BEGIN:VEVENT SUMMARY:Yue-Zhou Li (Princeton University) DTSTART:20241016T140000Z DTEND:20241016T150000Z DTSTAMP:20260404T131150Z UID:AnLy/45 DESCRIPTION:Title: A universal cutoff for field theory with gravity\nby Yue-Zhou Li (Princeton University) as part of AnLy Strings and Fields online seminars\ n\n\nAbstract\nThere is a longstanding argument that local field theory wi th gravity must break down at the species scale\, which is much lower than the Planck scale by the number of species. We aim to improve the understa nding of this statement. We analyze the one-loop effects of massive fields on the graviton scattering and the analyticity and unitarity allows us to put numerical bounds on the number of light species. Around the scale whe re the field theory breaks down\, we instead analyze the partial waves and observe that possible UV scenarios with gravity\, such as string theory\, all exhibit significant high-spin contents. This motivates a concept "hig h-spin onset scale"\, which qualitatively coincides with string scale or h igher dimensional Plank scale\, depending on the UV scenarios. The suggest ion is that the high-spin onset scale is a universal cutoff for field theo ry\, beyond which the local field description should not exist.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/45/ END:VEVENT BEGIN:VEVENT SUMMARY:Andrea Dei (Chicago University\, EFI) DTSTART:20241002T140000Z DTEND:20241002T150000Z DTSTAMP:20260404T131150Z UID:AnLy/46 DESCRIPTION:Title: On supergravity and noncritical strings\nby Andrea Dei (Chicago U niversity\, EFI) as part of AnLy Strings and Fields online seminars\n\n\nA bstract\nWhat is the string theory dual to 4d N=2 Super Yang Mills? Motiva ted by this question\, I will revisit some “noncritical” superstring m odels: these are string theories defined in less than ten spacetime dimens ions. Focusing on the setup with 6d Poincaré invariance\, I will explain how a careful worldsheet analysis allows to identify the leading-order eff ective theories for the lowest modes. These are seven-dimensional\, maxima lly supersymmetric gauged supergravities. The noncritical string can be vi ewed as a special case of a discrete series of backgrounds labelled by an integer k: the “noncritical” value is k = 2\, while for k → ∞ one recovers a weakly-curved 10d target space. We will discuss the worldsheet approach by boundary states and BPS solutions to the supergravity equation s of motion.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/46/ END:VEVENT BEGIN:VEVENT SUMMARY:Michael Nee (Harvard University) DTSTART:20241112T150000Z DTEND:20241112T160000Z DTSTAMP:20260404T131150Z UID:AnLy/47 DESCRIPTION:Title: Axion couplings in Heterotic String Theory\nby Michael Nee (Harva rd University) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nThe couplings of axions to gauge bosons are highly restricted in Gr and Unified Theories and heterotic string models. The topological nature o f these couplings allows them to be matched from the UV to the IR\, and th e ratio of the anomaly with photons and gluons for any axion is fixed by U V physics. This implies that in these theories there is a single axion\, t he QCD axion\, with an anomalous coupling to photons. Other light axion-li ke particles can couple to photons by mixing through the QCD axion portal and lie to the right of the QCD line in the mass-coupling plane. A discove ry of an axion to the left of the QCD line can rule out unified theories a nd some heterotic models. Axion experiments are therefore experimental pro bes of unification and string theory.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/47/ END:VEVENT BEGIN:VEVENT SUMMARY:Jakob Moritz (CERN) DTSTART:20241127T150000Z DTEND:20241127T160000Z DTSTAMP:20260404T131150Z UID:AnLy/48 DESCRIPTION:Title: De Sitter candidates in string theory\nby Jakob Moritz (CERN) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nThe simples t cosmology compatible with the accelerated expansion of our universe is d e Sitter space. Yet\, more than 25 years after the discovery of ``dark ene rgy’’\, concrete de Sitter vacua of string theory have remained elusiv e. In this talk I will present the first fully concrete string compactific ations that yield\, at leading order in the string loop and $\\alpha’$ e xpansions\, de Sitter vacua of a form envisioned by Kachru\, Kallosh\, Lin de and Trivedi (KKLT) more than 20 years ago. I will begin by reviewing th e KKLT proposal and its complex set of delicately balanced ingredients. Th en\, I will show how all the required features come together in actual exa mples: I will define explicit Calabi-Yau orientifolds and choices of quant ized fluxes\, and derive the corresponding four-dimensional effective supe rgravity theories. Each example includes a strongly warped ``Klebanov-Stra ssler throat'' region containing a single anti-D3-brane\, whose supersymme try-breaking energy\, computed at leading order in $\\alpha'$\, causes an uplift to a metastable de Sitter vacuum in which all moduli are stabilized . I will conclude by emphasizing a set of outstanding computational proble ms that need to be overcome in order to determine whether these vacua surv ive (presently unknown) subleading corrections\, and thus promote to full solutions of string theory.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/48/ END:VEVENT BEGIN:VEVENT SUMMARY:Philippe Brax (IPhT\, Saclay) DTSTART:20241211T150000Z DTEND:20241211T160000Z DTSTAMP:20260404T131150Z UID:AnLy/49 DESCRIPTION:Title: Axio-dilaton screened cosmology\nby Philippe Brax (IPhT\, Saclay) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nI will review the problems caused by light scalar fields in particular with respe ct to gravitational tests and consider a new type of screening mechanism w hich allows to evade them. This involves two fields\, an axion-like field and a dilaton\, for which I will also present new results on their cosmolo gy and a link to early dark energy.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/49/ END:VEVENT BEGIN:VEVENT SUMMARY:Linus Wulff (Masaryk University) DTSTART:20250115T150000Z DTEND:20250115T160000Z DTSTAMP:20260404T131150Z UID:AnLy/50 DESCRIPTION:Title: No manifest T-duality at alpha'^3\nby Linus Wulff (Masaryk Univer sity) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nT- duality leads to a (continuous) O(d\,d) symmetry of the tree-level closed string effective action reduced from D=10 to 10-d. However\, this symmetry appears only after certain field redefinitions. I will argue that when th e $\\alpha^{\\prime \\\,3}$ correction is included these field redefinitio ns cannot be lifted to ten dimensions. This poses a problem for approaches like generalized geometry and double field theory\, which assume an O(d\, d) structure is present before reduction.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/50/ END:VEVENT BEGIN:VEVENT SUMMARY:Chris Hull (Imperial College London) DTSTART:20250129T150000Z DTEND:20250129T160000Z DTSTAMP:20260404T131150Z UID:AnLy/51 DESCRIPTION:Title: Monopoles\, Dirac Strings and Generalised Symmetries\nby Chris Hu ll (Imperial College London) as part of AnLy Strings and Fields online sem inars\n\n\nAbstract\nDirac’s action for electrically and magnetically ch arged particles interacting with the electromagnetic field involves singul ar Dirac strings which introduce a form of non-locality in the formulation . These are invisible provided they do not intersect charged particle worl d-lines – this is known as the Dirac veto. It is shown that this system has 1-form generalised symmetries and the Dirac veto can be viewed as a re striction to configurations in which certain anomalies vanish.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/51/ END:VEVENT BEGIN:VEVENT SUMMARY:Miguel Montero (IFT\, Madrid) DTSTART:20250312T150000Z DTEND:20250312T160000Z DTSTAMP:20260404T131150Z UID:AnLy/52 DESCRIPTION:Title: The DGKT scenario and the Weak Gravity Conjecture\nby Miguel Mont ero (IFT\, Madrid) as part of AnLy Strings and Fields online seminars\n\n\ nAbstract\nI will discuss how generic quantum corrections lift the moduli space of BPS branes in 4d N=1 scale-separated solutions like DGKT. This me ans that there is a tension between this scenario and the WGC for membrane s\, which demands the existence of an exactly extremal brane. Similar tens ions exist in any 4d N=1 scenario not protected by a parity symmetry\, and I will mention some examples.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/52/ END:VEVENT BEGIN:VEVENT SUMMARY:Niall Macpherson (Oviedo University) DTSTART:20250319T150000Z DTEND:20250319T160000Z DTSTAMP:20260404T131150Z UID:AnLy/53 DESCRIPTION:Title: G-structures for AdS2 and new solutions with N=6 supersymmetry\nb y Niall Macpherson (Oviedo University) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nI will review the recent classification of minimally supersymmetric AdS2 solutions of type II supergravity in terms o f G-structures which provides necessary\, sufficient and purely geometric conditions for supersymmetry. Together with an earlier work focused on d=1 1\, this puts AdS2 on the same geometric footing as its higher dimensional AdS counterparts and provides powerful tools for the construction of many backgrounds of physical interest. Examples include: black-hole near horiz on geometries\, holographic duals to superconformal quantum mechanics and duals to conformal defects in higher dimensional CFTs.\n\nI will explain h ow these G-structure conditions may also be leveraged to construct solutio ns with extended supersymmetry and will provide some examples in this vein . Amongst these my main focus will be on recently constructed solutions pr eserving N=6 supersymmetry in massive type IIA and their dual description as well as a broad class in type IIB whose local form can be expressed in terms of 2 holomorphic functions.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/53/ END:VEVENT BEGIN:VEVENT SUMMARY:Daniele Oriti (Universidad Complutense de Madrid) DTSTART:20250409T140000Z DTEND:20250409T150000Z DTSTAMP:20260404T131150Z UID:AnLy/54 DESCRIPTION:Title: Late-time cosmic acceleration from Quantum Gravity\nby Daniele Or iti (Universidad Complutense de Madrid) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nWe show how a cosmological dynamics with a late-time cosmic acceleration and an asymptotic deSitter regime can be ob tained from hydrodynamics on minisuperspace\, a framework generalising qua ntum cosmology with non-linear terms. We also show how this hydrodynamics framework can be derived from fundamental quantum gravity models within th e tensorial group field theory formalism\, an approach closely related to lattice quantum gravity and loop quantum gravity. If time allows\, we disc uss other results within the same framework\, concerning emergent cosmolog ical physics\, as well as other research directions leading to it.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/54/ END:VEVENT BEGIN:VEVENT SUMMARY:Gabriele Casagrande (CPHT\, Polytechnique) DTSTART:20250514T140000Z DTEND:20250514T150000Z DTSTAMP:20260404T131150Z UID:AnLy/55 DESCRIPTION:Title: A unique coupling of the massive spin-2 field to supergravity\nby Gabriele Casagrande (CPHT\, Polytechnique) as part of AnLy Strings and Fi elds online seminars\n\n\nAbstract\nIn this talk\, I will discuss the coup ling of a massive spin-2 field to (undeformed) D=4\, N=1 supergravity. We do so by constructing the general stress-energy tensor multiplet for the N =1 massive spin-2 supermultiplet. We show that\, at leading order in the P lanck mass\, this coupling is unique and characterized by a specific non-m inimal coupling to the Riemann tensor. The massive spin-2 sector of this u nique coupling reproduces the one of an oscillator mode in open string the ory. The massive spin-1 sector\, on the other hand\, includes a higher-der ivative term that may lead to violations of causality\, which can be resol ved by introducing infinitely many higher-spin fields\, similar to the Reg ge trajectories in string theory. Moreover\, we argue that this coupling i s genuinely different from the one arising from Kaluza-Klein reductions of higher-dimensional supergravities\, which we show leads instead to a defo rmation of the massless supersymmetry transformations.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/55/ END:VEVENT BEGIN:VEVENT SUMMARY:Fridrik Freyr Gautason (University of Southampton) DTSTART:20250618T140000Z DTEND:20250618T150000Z DTSTAMP:20260404T131150Z UID:AnLy/56 DESCRIPTION:Title: Localisation of M2-branes and Ensembles\nby Fridrik Freyr Gautaso n (University of Southampton) as part of AnLy Strings and Fields online se minars\n\n\nAbstract\nI will discuss the M2-brane partition function for a large class of asymptotically locally $AdS_4 \\times S^7$ spacetimes. I w ill show how supersymmetry localises the M2-brane position to a fixed poin t of an R-symmetry Killing vector. I will then discuss the one-loop partit ion function of instantonic M2-branes and show that it is assembled out of building blocks familiar to 3D supersymmetric quantum field theories. I w ill close out with arguments that M theory on $AdS_4$ is dual to 3D CFT (s uch as ABJM) in the grand canonical ensemble. In that context the instanto n partition function we obtain is one-loop exact.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/56/ END:VEVENT BEGIN:VEVENT SUMMARY:Mariana Graña (IPhT Saclay) DTSTART:20251008T140000Z DTEND:20251008T150000Z DTSTAMP:20260404T131150Z UID:AnLy/57 DESCRIPTION:Title: The boundary of symmetric spaces and the swampland distance conjectur e\nby Mariana Graña (IPhT Saclay) as part of AnLy Strings and Fields online seminars\n\n\nAbstract\nThe swampland distance conjecture\, stating that at any boundary of moduli space there is a tower of states becoming exponentially massless\, has been checked in a wide variety of setups\, an d is connected to other conjectures supported themselves by bottom-up argu ments. However\, as it stands it lacks a bottom-up explanation. Here we pr ove it under mild assumptions for locally symmetric moduli spaces\, by cha racterising the spectrum and geodesics that go to the boundary using just group-theory concepts. With this\, we can compute exponential rate of dec ay of the mass for any symmetric space and any representation of the spect rum\, showing that the distance conjecture is always satisfied. Moreover\, assuming only one irrep\, we classify all groups and particle representat ions compatible with the decay rates of KK and string towers. Some of them are in the known landscape of string theory compactifications\, while a h andful remain to be found or proven to be in the swampland.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/57/ END:VEVENT BEGIN:VEVENT SUMMARY:Dimitrios Chatzis (Swansea University) DTSTART:20251015T140000Z DTEND:20251015T150000Z DTSTAMP:20260404T131150Z UID:AnLy/58 DESCRIPTION:Title: Conformal to confining SQFTs through holography\nby Dimitrios Cha tzis (Swansea University) as part of AnLy Strings and Fields online semina rs\n\n\nAbstract\nHolographic methods have long provided valuable insights into QCD-like theories and other strongly coupled systems. In this talk\, I present new work in this direction\, which uses SUSY solitons in 5d gau ged supergravity to systematically construct smooth gravity backgrounds du al to confining and gapped systems. I will introduce novel solutions acros s different supergravity theories\, including setups with fundamental matt er. The dual field theories flow from UV superconformal fixed points to we ll-defined IR SQFTs in one dimension lower. A range of field-theory observ ables is computed holographically\, exhibiting universality and providing strong evidence for confinement and a mass gap. Finally\, I will highlight an intriguing numerical result concerning the entanglement entropy betwee n different gauge and fundamental degrees of freedom.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/58/ END:VEVENT BEGIN:VEVENT SUMMARY:Ioannis Papadimitriou (Athens U.) DTSTART:20251105T150000Z DTEND:20251105T160000Z DTSTAMP:20260404T131150Z UID:AnLy/59 DESCRIPTION:Title: Wess-Zumino effective action for 4d N=1 SCFTs\nby Ioannis Papadim itriou (Athens U.) as part of AnLy Strings and Fields online seminars\n\n\ nAbstract\nI will present a new computation of the Wess-Zumino effective a ction for generic N=1 superconformal field theories in four dimensions usi ng off-shell N=1 conformal supergravity in the components formalism. The r esult currently includes terms up to second order in the fermions. I will discuss the connection of this result with the superspace expression of Sc hwimmer and Theisen\, and comment on the relation with the supersymmetric Casimir energy and the holomorphicity of the partition function on supersy mmetric backgrounds.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/59/ END:VEVENT BEGIN:VEVENT SUMMARY:Hynek Paul (KU Leuven) DTSTART:20251112T150000Z DTEND:20251112T160000Z DTSTAMP:20260404T131150Z UID:AnLy/60 DESCRIPTION:Title: Correlation functions for non-conformal Dp-brane holography\nby H ynek Paul (KU Leuven) as part of AnLy Strings and Fields online seminars\n \n\nAbstract\nI will explain how we can study correlation functions of loc al operators in d-dimensional maximally supersymmetric Yang-Mills theories in the planar strongly-coupled limit via holography. The relevant supergr avity backgrounds (obtained from the near-horizon limit of Dp-branes (with p=d-1) enjoy a scaling similarity\, giving rise to an auxiliary AdS space . This allows us to derive simple rules analogous to Witten diagrams for t he holographic calculation of correlation functions in these non-conformal setups. Using this framework\, I will then explain how to analytically co mpute two- and three-point correlators of scalar operators\, leading to ne w results which could be tested using lattice QFT methods. Based on [2503. 18770] with Nikolay Bobev and Guillermo Mera Álvarez.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/60/ END:VEVENT BEGIN:VEVENT SUMMARY:Colin Sterckx (Brussels\, ULB) DTSTART:20251126T150000Z DTEND:20251126T160000Z DTSTAMP:20260404T131150Z UID:AnLy/61 DESCRIPTION:Title: How to uplift non-maximal gauged supergravities\nby Colin Sterckx (Brussels\, ULB) as part of AnLy Strings and Fields online seminars\n\n\n Abstract\nEmbedding lower-dimensional supergravities into type II and elev en-dimensional theories has been central to constructing new supergravity solutions and analysing them using string-theoretic tools such as the AdS/ CFT correspondence. In this talk\, I will present a general framework for uplifting non-maximal gauged supergravities using exceptional field theory and generalised geometry\, extending techniques previously available only for maximal supergravities. Our method put constraints on the internal ma nifolds\, which must admit an effective action of the gauge group\, and we show that the consistency of the uplift reduces to a PDE on the quotient of the internal manifold by this action. I will illustrate the framework t hrough the complete classification of type IIB uplifts of four-dimensional half-maximal SO(4)-gauged supergravity. This will provide consistent trun cations around any of the D’Hoker–Estes–Gutperle AdS_4 solutions.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/61/ END:VEVENT BEGIN:VEVENT SUMMARY:Alek Bedroya (Princeton U.) DTSTART:20260114T150000Z DTEND:20260114T160000Z DTSTAMP:20260404T131150Z UID:AnLy/62 DESCRIPTION:Title: Holographic Constraints on the String Landscape\nby Alek Bedroya (Princeton U.) as part of AnLy Strings and Fields online seminars\n\n\nAbs tract\nI will discuss scale separation in top-down string theory construct ions of AdS vacua\, focusing on proposals based on compactifications on Ri cci-flat manifolds such as DGKT and KKLT. I will then present a general ar gument that the putative CFT duals of such scale-separated AdS vacua canno t emerge as infrared limits of any brane configuration in string theory\, implying that such vacua are unlikely to be UV complete. This explains why stable AdS vacua in string theory are essentially higher-dimensional in n ature. If time permits\, I will conclude with further holographic constrai nts on scalar potentials with implications for cosmology.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/62/ END:VEVENT BEGIN:VEVENT SUMMARY:Ivano Basile (Garching\, Max Planck Inst.) DTSTART:20260128T150000Z DTEND:20260128T160000Z DTSTAMP:20260404T131150Z UID:AnLy/63 DESCRIPTION:Title: Horror vacui: instabilities in scale-separated Casimir compactificati ons\nby Ivano Basile (Garching\, Max Planck Inst.) as part of AnLy Str ings and Fields online seminars\n\n\nAbstract\nFinding reliable scale-sepa rated vacua with no moduli in the string landscape is a considerable chall enge\, yet it is essential to connect string theory to our universe. Among several attempts\, toroidal compactifications supported by fluxes and Cas imir energy stand out for their simplicity and degree of parametric contro l. In particular\, there exist simple such compactifications of eleven-dim ensional supergravity leading to non-supersymmetric weakly curved anti-de Sitter solutions in four dimensions. I will show that these solutions are perturbatively (and non-perturbatively) unstable\, and thus do not pertain to bona fide four-dimensional effective field theories.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/63/ END:VEVENT BEGIN:VEVENT SUMMARY:Naman Agarwal (Manitoba U.) DTSTART:20260225T150000Z DTEND:20260225T160000Z DTSTAMP:20260404T131150Z UID:AnLy/64 DESCRIPTION:Title: Toward an Effective Theory of the Volume Modulus\nby Naman Agarwa l (Manitoba U.) as part of AnLy Strings and Fields online seminars\n\n\nAb stract\nIn this talk\, I will talk about my recent work with collaborators where we investigate the 4-dimensional effective theory of the warped vol ume modulus in the presence of stabilizing effects from gaugino condensati on by analyzing the linearized 10-dimensional supergravity equations of mo tion. Warping is generally expected to scale down the masses of bulk modes to the IR scale at the tip of a throat. We find that the mass of the warp ed volume modulus evades expectations and is largely insensitive to the ef fects of warping\, even in strongly warped backgrounds. Instead\, the mass is parametrically tied to the 4-dimensional AdS curvature scale $m^2 \\si m \\mathcal{O}(1) \\hat{R}_{AdS}$\, presenting a challenge for scale separ ation in these backgrounds. We trace this effect to a universal contributi on arising from the 10-dimensional equations of motion\, and comment on th e importance of a 10-dimensional treatment of the warped volume modulus fo r effective field theories and model building.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/64/ END:VEVENT BEGIN:VEVENT SUMMARY:Victor Franken (Gent U.) DTSTART:20260318T150000Z DTEND:20260318T160000Z DTSTAMP:20260404T131150Z UID:AnLy/65 DESCRIPTION:Title: Holographic quantum tasks in the static patch\nby Victor Franken (Gent U.) as part of AnLy Strings and Fields online seminars\n\n\nAbstract \nIn the AdS/CFT correspondence\, direct scattering in the bulk may not ha ve a local boundary analog. A nonlocal implementation on the boundary requ ires O(1/G​) mutual information. This statement is formalized by the con nected wedge theorem\, which can be proven using general relativity within AdS_3​ but also by applying quantum information theory on the boundary\ , suggesting that the theorem applies to any holographic duality. We exami ne scattering within the static patch of asymptotically dS_3 spacetime\, w hich is conjectured to be described by a quantum theory on the stretched h orizon in static patch holography. We prove that causality on the horizon should be induced from null infinities to maintain consistency with the th eorem. Specifically\, signals propagating in the static patch are associat ed with local operators at null infinity. These results suggest a novel co nnection between static patch holography and the dS/CFT correspondence.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/65/ END:VEVENT BEGIN:VEVENT SUMMARY:Salvatore Raucci (Madrid\, IFT) DTSTART:20260401T140000Z DTEND:20260401T150000Z DTSTAMP:20260404T131150Z UID:AnLy/66 DESCRIPTION:Title: AdS vacua of non-supersymmetric strings\nby Salvatore Raucci (Mad rid\, IFT) as part of AnLy Strings and Fields online seminars\n\n\nAbstrac t\nThe non-supersymmetric string landscape remains largely unexplored\, la cking the systematic tools provided by the supergravity equations. In this talk\, I will discuss cases where the equations of motion of tachyon-free \, non-supersymmetric string theories can be recast as algebraic condition s. Focusing on the ten-dimensional SO(16)×SO(16) heterotic string\, I wil l then present a systematic framework based on a fictitious Kaluza-Klein r eduction\, yielding AdS4 solutions on cosets G/H with H-valued gauge field s. If time permits\, I will outline the sigma-model version of the systema tic approach and comment on the generic features of the resulting vacua.\n LOCATION:https://stable.researchseminars.org/talk/AnLy/66/ END:VEVENT END:VCALENDAR