\nThe talk is based on a joint work with Yoshiko Ogata and Yuji Tachikawa in arXiv:2 004.06458.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/11/ END:VEVENT BEGIN:VEVENT SUMMARY:Nicolas Rougerie (University of Grenoble Alpes) DTSTART;VALUE=DATE-TIME:20200728T130000Z DTEND;VALUE=DATE-TIME:20200728T140000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/12 DESCRIPTION:Title: Two modes approximation for bosons in a double well potential\n by Nicolas Rougerie (University of Grenoble Alpes) as part of One world IA MP mathematical physics seminar\n\n\nAbstract\nWe study the mean-field lim it for the ground state of bosonic particles in a double-well potential\, jointly with the limit of large inter-well separation/large potential ener gy barrier. Two one-body wave-functions are then macroscopially occupied\, one for each well. The physics in this two-modes subspace is usually desc ribed by a Bose-Hubbard Hamiltonian\, yielding in particular the transitio n from an uncorrelated "superfluid" state (each particle lives in both pot ential wells) to a correlated "insulating" state (half of the particles li ve in each potential well). \n\nThrough precise energy expansions we pro ve that the variance of the number of particles within each well is suppre ssed (violation of the central limit theorem)\, a signature of a correlate d ground state. \n\nQuantum fluctuations around the two-modes description are particularly relevant\, for they give energy contributions of the same order as the energy difference due to suppressed variances in the two-mod es subspace. We describe them in terms of two independent Bogoliubov Hamil tonians\, one for each potential well.\n\nJoint work with Alessandro Olgia ti and Dominique Spehner\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/12/ END:VEVENT BEGIN:VEVENT SUMMARY:Hugo Duminil-Copin (IHES / University of Geneva) DTSTART;VALUE=DATE-TIME:20200721T130000Z DTEND;VALUE=DATE-TIME:20200721T140000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/13 DESCRIPTION:Title: Marginal triviality of the scaling limits of critical 4D Ising and &phi\;_4^4 models\nby Hugo Duminil-Copin (IHES / University of Geneva) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nIn this talk\, we will discuss the scaling limits of spin fluctuations in fou r-dimensional Ising-type models with nearest-neighbor ferromagnetic intera ction at or near the critical point are Gaussian and its implications from the point of view of Euclidean Field Theory. Similar statements will be p roven for the &lambda\;&phi\;4 fields over R^4 with a lattice ultraviolet cutoff\, in the limit of infinite volume and vanishing lattice spacing. Th e proofs are enabled by the models' random current representation\, in whi ch the correlation functions' deviation from Wick's law is expressed in te rms of intersection probabilities of random currents with sources at dista nces which are large on the model's lattice scale. Guided by the analogy w ith random walk intersection amplitudes\, the analysis focuses on the impr ovement of the so-called tree diagram bound by a logarithmic correction te rm\, which is derived here through multi-scale analysis.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/13/ END:VEVENT BEGIN:VEVENT SUMMARY:Antti Kupiainen (University of Helsinki) DTSTART;VALUE=DATE-TIME:20200908T140000Z DTEND;VALUE=DATE-TIME:20200908T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/14 DESCRIPTION:Title: Integrability of Liouville Conformal Field Theory\nby Antti Kup iainen (University of Helsinki) as part of One world IAMP mathematical phy sics seminar\n\n\nAbstract\nA. Polyakov introduced Liouville Conformal Fie ld theory (LCFT) in 1981 as a way to put a natural measure on the set of R iemannian metrics over a two dimensional manifold. Ever since\, the work o f Polyakov has echoed in various branches of physics and mathematics\, ran ging from string theory to probability theory and geometry. In the context of 2D quantum gravity models\, Polyakovâ€™s approach is conjecturall y equivalent to the scaling limit of Random Planar Maps and through the Al day-Gaiotto- Tachikava correspondence LCFT is conjecturally related to cer tain 4D Yang-Mills theories. Through the work of Dorn\,Otto\, Zamolodchiko v and Zamolodchikov and Teschner LCFT is believed to be to a certain exten t integrable. \n\nI will review a probabilistic construction of LCFT devel oped together with David\, Rhodes and Vargas and recent proofs concerning the integrability of LCFT: \n-The proof in a joint work with Rhodes and Va rgas of the DOZZ formula (Annals of Mathematics\, 81-166\,191 (2020) \n-Th e proof in a joint work with Guillarmou\, Rhodes and Vargas of the bootstr ap conjecture for LCFT (arXiv:2005.11530).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/14/ END:VEVENT BEGIN:VEVENT SUMMARY:Victor Ivrii (University of Toronto) DTSTART;VALUE=DATE-TIME:20200915T140000Z DTEND;VALUE=DATE-TIME:20200915T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/15 DESCRIPTION:Title: Scott and Thomas-Fermi approximations to electronic density\nby Victor Ivrii (University of Toronto) as part of One world IAMP mathematic al physics seminar\n\n\nAbstract\nIn heavy atoms and molecules\, on the di stances $ a \\ll Z^{-1/2}$ from one of the nuclei (with a charge $Z_m$)\, we prove that the ground state electronic density $\\rho_\\Psi (x)$ is app roximated in $L^p$-norm by the ground state electronic density for a singl e atom in the model with no interactions between electrons.\n\nFurther\, o n the distances $a \\gg Z^{-1}$ from all of the nuclei (with a charge $Z_1 \,\\ldots\, Z_m$) we prove that $\\rho_\\Psi (x)$ is approximated in $L^p$ -norm\, by the Thomas-Fermi density. We cover both non-relativistic and re lativistic cases.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/15/ END:VEVENT BEGIN:VEVENT SUMMARY:Alessandro Giuliani (University Roma Tre) DTSTART;VALUE=DATE-TIME:20200929T140000Z DTEND;VALUE=DATE-TIME:20200929T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/16 DESCRIPTION:Title: Non-renormalization of the `chiral anomaly' in interacting lattice Weyl semimetals\nby Alessandro Giuliani (University Roma Tre) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nWeyl semimet als are 3D condensed matter systems characterized by a degenerate Fermi su rface\, consisting of a pair of `Weyl nodes'. Correspondingly\, in the inf rared limit\, these systems behave effectively as Weyl fermions in 3+1 dim ensions. We consider a class of interacting 3D lattice models for Weyl sem imetals and prove that the quadratic response of the quasi-particle flow b etween the Weyl nodes\, which is the condensed matter analogue of the chir al anomaly in QED4\, is universal\, that is\, independent of the interacti on strength and form. Universality\, which is the counterpart of the Adler -Bardeen non-renormalization property of the chiral anomaly for the infrar ed emergent description\, is proved to hold at a non-perturbative level\, notwithstanding the presence of a lattice\n(in contrast with the original Adler-Bardeen theorem\, which is perturbative and requires relativistic in variance to hold). The proof relies on constructive bounds for the Euclide an ground state correlations combined with lattice Ward Identities\, and i t is valid arbitrarily close to the critical point where the Weyl points m erge and the relativistic description breaks down. Joint work with V. Mast ropietro and M. Porta.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/16/ END:VEVENT BEGIN:VEVENT SUMMARY:Nalini Anantharaman (Strasbourg) DTSTART;VALUE=DATE-TIME:20201103T140000Z DTEND;VALUE=DATE-TIME:20201103T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/17 DESCRIPTION:Title: The bottom of the spectrum of a random hyperbolic surface\nby N alini Anantharaman (Strasbourg) as part of One world IAMP mathematical phy sics seminar\n\n\nAbstract\nI will report on work in progress with Laura M onk\, where we study the bottom of the spectrum of the laplacian\, on a co mpact hyperbolic surface chosen at random\, in the limit of growing genus. We pick combinatorial ideas from the study of random regular graphs\, to propose a strategy to prove that\, with high probability\, there are no ei genvalues below $1/4-\\epsilon$.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/17/ END:VEVENT BEGIN:VEVENT SUMMARY:Peter Hintz (MIT) DTSTART;VALUE=DATE-TIME:20201110T140000Z DTEND;VALUE=DATE-TIME:20201110T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/18 DESCRIPTION:Title: Linear stability of slowly rotating Kerr spacetimes\nby Peter H intz (MIT) as part of One world IAMP mathematical physics seminar\n\n\nAbs tract\nI will describe joint work with Dietrich Häfner and András Vasy i n which we study the asymptotic behavior of linearized gravitational pertu rbations of Schwarzschild or slowly rotating Kerr black hole spacetimes. W e show that solutions of the linearized Einstein equation decay at an inve rse polynomial rate to a stationary solution (given by an infinitesimal va riation of the mass and angular momentum of the black hole)\, plus a pure gauge term. The proof uses a detailed description of the resolvent of an a ssociated wave equation on symmetric 2-tensors near zero energy.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/18/ END:VEVENT BEGIN:VEVENT SUMMARY:Bruno Nachtergaele (UC Davis) DTSTART;VALUE=DATE-TIME:20201027T140000Z DTEND;VALUE=DATE-TIME:20201027T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/19 DESCRIPTION:Title: Gapped ground state phases of lattice systems - Stability of the bu lk gap\nby Bruno Nachtergaele (UC Davis) as part of One world IAMP mat hematical physics seminar\n\n\nAbstract\nI will give an overview of stabil ity results for the spectral gap above the ground states of quantum lattic e systems obtained in the past decade and explain the overall strategy int roduced by Bravyi\, Hastings\, and Michalakis. A new result I will present proves the stability of the bulk gap for infinite systems with an approac h that bypasses possible gapless boundary modes (joint work with Bob Sims and Amanda Young).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/19/ END:VEVENT BEGIN:VEVENT SUMMARY:Yoshiko Ogata (University of Tokyo) DTSTART;VALUE=DATE-TIME:20201215T140000Z DTEND;VALUE=DATE-TIME:20201215T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/20 DESCRIPTION:Title: Classification of symmetry protected topological phases in quantum spin systems\nby Yoshiko Ogata (University of Tokyo) as part of One wo rld IAMP mathematical physics seminar\n\n\nAbstract\nA Hamiltonian is in a SPT phase with a given symmetry if it cannot be \nsmoothly deformed into a trivial Hamiltonian without a phase transition\, \nif the deformation p reserves the symmetry\,\nwhile it can be smoothly deformed into a trivial Hamiltonian without a \nphase transition\, if the symmetry is broken durin g the deformation.\nWe consider this problem for one- and two-dimensional quantum spin systems with on-site finite \ngroup symmetries.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/20/ END:VEVENT BEGIN:VEVENT SUMMARY:Jeremy Quastel (University of Toronto) DTSTART;VALUE=DATE-TIME:20201020T140000Z DTEND;VALUE=DATE-TIME:20201020T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/21 DESCRIPTION:Title: Towards KPZ Universality\nby Jeremy Quastel (University of Toro nto) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\ nThe 1-d KPZ universality class contains random interface growth models\na s well as random polymer free energies and driven diffusive systems. \nTh e KPZ fixed point has now been determined\, through the exact solution of a special model\nin the class\, TASEP\, and is expected to describe the as ymptotic fluctuations for all models in the class.\nIt is an integrable Ma rkov process\, with transition probabilities described by a system of inte grable PDE's.\n

\nVery recently\, new techniques have become available to prove \nthe convergence of the KPZ equation itself\, as well as some no n-integrable extensions\nof TASEP\, to the KPZ fixed point. This talk wil l be a gentle introduction to these developments\nwith no prior knowledge assumed. The results are\, variously\, joint works with \nDaniel Remenik\ , Konstantin Matetski\, and Sourav Sarkar.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/21/ END:VEVENT BEGIN:VEVENT SUMMARY:Roland Bauerschmidt (University of Cambridge) DTSTART;VALUE=DATE-TIME:20201124T140000Z DTEND;VALUE=DATE-TIME:20201124T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/22 DESCRIPTION:Title: The Coleman correspondence at the free fermion point\nby Roland Bauerschmidt (University of Cambridge) as part of One world IAMP mathemat ical physics seminar\n\n\nAbstract\nTwo-dimensional statistical and quantu m field theories are\nspecial in many ways. One striking instance of this is the equivalence\nof certain bosonic and fermionic fields\, known as bos onization. I will\nfirst review this correspondence in the explicit instan ce of the\nmassless Gaussian free field and massless Euclidean Dirac fermi ons. I\nwill then present a result that extends this correspondence to the \nnon-Gaussian `massless' sine-Gordon field on $\\R^2$ at $\\beta=4\\pi$ a nd\nmassive Dirac fermions. This is an instance of Coleman's prediction th at\nthe `massless' sine-Gordon model and the massive Thirring model are\ne quivalent. We use this correspondence to show that correlations of the\n`m assless' sine-Gordon model decay exponentially for $\\beta=4\\pi$.\nThis i s joint work with C. Webb (arXiv:2010.07096).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/22/ END:VEVENT BEGIN:VEVENT SUMMARY:Svitlana Mayboroda (University of Minnesota) DTSTART;VALUE=DATE-TIME:20201013T140000Z DTEND;VALUE=DATE-TIME:20201013T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/23 DESCRIPTION:Title: The landscape law for the integrated density of states\nby Svit lana Mayboroda (University of Minnesota) as part of One world IAMP mathema tical physics seminar\n\n\nAbstract\nComplexity of the geometry\, randomne ss of the potential\, and many other irregularities of the system can caus e powerful\, albeit quite different\, manifestations of localization\, a p henomenon of sudden confinement of waves\, or eigenfunctions\, to a small portion of the original domain. In the present talk we show that behind a possibly disordered system there exists a structure\, referred to as a lan dscape function\, which can predict the location and shape of the localize d eigenfunctions\, a pattern of their exponential decay\, and deliver accu rate bounds for the corresponding eigenvalues. In particular\, we establis h the "landscape law"\, the first non-asymptotic estimates from above and below on the integrated density of states of the Schroedinger operator usi ng a counting function for the minima of the localization landscape. The r esults are deterministic\, and rely on a new uncertainty principle. Narrow ing down to the context of disordered potentials\, we derive the best curr ently available bounds on the integrated density of states for the Anderso n model.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/23/ END:VEVENT BEGIN:VEVENT SUMMARY:Stefan Hollands (University of Leipzig) DTSTART;VALUE=DATE-TIME:20201117T140000Z DTEND;VALUE=DATE-TIME:20201117T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/24 DESCRIPTION:Title: (In)determinism Inside Black Holes\nby Stefan Hollands (Univers ity of Leipzig) as part of One world IAMP mathematical physics seminar\n\n \nAbstract\nIn classical General Relativity\, the values of fields on spac etime are\nuniquely determined by their initial values within its "domain of\ndependence". However\, it may occur that the\nspacetime under consider ation extends beyond this domain\, and\nfields\, therefore\, are not entir ely determined by their initial data. In fact\, such a naive\nfailure of d eterminism occurs inside all physically relevant black holes.\n\nThe bound ary of the region determined by the initial data is\ncalled the "Cauchy ho rizon". Penrose has proposed ("strong cosmic censorship conjecture")\nthat the Cauchy horizon is actually unstable in the sense that the slightest p erturbation caused\nby remnant fields convert it to a final singularity. W hether or not this is the case --\nand thus whether there is a real proble m with determinism -- has been put into question recently.\n\nIn this coll oquium I ask wheter quantum effects will come to the rescue of strong cosm ic censorship.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/24/ END:VEVENT BEGIN:VEVENT SUMMARY:Ian Jauslin (Princeton University) DTSTART;VALUE=DATE-TIME:20200922T140000Z DTEND;VALUE=DATE-TIME:20200922T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/25 DESCRIPTION:Title: An effective equation to study Bose gasses at both low and high den sities\nby Ian Jauslin (Princeton University) as part of One world IAM P mathematical physics seminar\n\n\nAbstract\nI will discuss an effective equation\, which is used to study the ground state\n of the interacting Bo se gas. The interactions induce many-body correlations\n in the system\, w hich makes it very difficult to study\, be it analytically or\n numericall y. A very successful approach to solving this problem is Bogolubov\n theor y\, in which a series of approximations are made\, after which the\n analy sis reduces to a one-particle problem\, which incorporates the many-body\n correlations. The effective equation I will discuss is arrived at by maki ng a\n very different set of approximations\, and\, like Bogolubov theory\ , ultimately\n reduces to a one-particle problem. But\, whereas Bogolubov theory is accurate\n only for very small densities\, the effective equatio n coincides with the\n many-body Bose gas at both low and at high densitie s.\n\n I will show some\n theorems which make this statement more precise\ , and present numerical\n evidence that this effective equation is remarka bly accurate for all\n densities\, small\, intermediate\, and large. That is\, the analytical and\n numerical evidence suggest that this effective e quation can capture many-body\n correlations in a one-particle picture bey ond what Bogolubov can accomplish.\n Thus\, this effective equation gives an alternative approach to study the low\n density behavior of the Bose ga s (about which there still are many important\n open questions). In additi on\, it opens an avenue to understand the physics of\n the Bose gas at int ermediate densities\, which\, until now\, were only\n accessible to Monte Carlo simulations.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/25/ END:VEVENT BEGIN:VEVENT SUMMARY:Alessandro Pizzo (University of Rome Tor Vergata) DTSTART;VALUE=DATE-TIME:20201201T140000Z DTEND;VALUE=DATE-TIME:20201201T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/26 DESCRIPTION:Title: Stability of gapped quantum chains under small perturbations\nb y Alessandro Pizzo (University of Rome Tor Vergata) as part of One world I AMP mathematical physics seminar\n\n\nAbstract\nWe consider a family of qu antum chains that has attracted much interest amongst people studying topo logical phases of matter. Their Hamiltonians are perturbations\, by intera ctions of short range\, of a Hamiltonian consisting of on-site terms and w ith a strictly positive energy gap above its ground-state energy. For inte ractions that are form-bounded w.r.t. the on-site Hamiltonian terms\, we prove that the spectral gap of the perturbed Hamiltonian above its ground- state energy is bounded from below by a positive constant uniformly in th e length of the chain\, for small values of a coupling constant.\n\nIn our proof we use a novel method based on local Lie-Schwinger conjugations of the Hamiltonians associated with connected subsets of the chain\, that ca n be also applied to complex Hamiltonians obtained by considering complex values of the coupling constant.\n\nWe can treat fermions and bosons on th e same footing\, and our technique does not face a large field problem\, e ven though bosons are involved\, in contrast to most approaches. Furthermo re the method can be extended to higher spatial dimensions.\n\n(Joint work with S. Del Vecchio\, J. Fröhlich\, and S. Rossi.)\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/26/ END:VEVENT BEGIN:VEVENT SUMMARY:Katrin Wendland (Albert-Ludwigs-Universität Freiburg) DTSTART;VALUE=DATE-TIME:20201208T140000Z DTEND;VALUE=DATE-TIME:20201208T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/27 DESCRIPTION:Title: On invariants shared by geometry and conformal field theory\nby Katrin Wendland (Albert-Ludwigs-Universität Freiburg) as part of One wor ld IAMP mathematical physics seminar\n\n\nAbstract\nI will recall how some conformal field theories can be given geometric interpretations. This can be useful from a practical point of view\, when geometric methods are tra nsferred from geometry to conformal field theory. I will in particular foc us on certain invariants that are shared by geometry and conformal field t heory\, including the complex elliptic genus. As we shall see\, this invar iant is also useful from a theoretical viewpoint\, since it captures infor mation about generic properties of certain theories.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/27/ END:VEVENT BEGIN:VEVENT SUMMARY:Clotilde Fermanian-Kammerer (Université\; Paris Est - Cr&eac ute\;teil Val de Marne) DTSTART;VALUE=DATE-TIME:20201006T140000Z DTEND;VALUE=DATE-TIME:20201006T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/28 DESCRIPTION:Title: Nonlinear quantum adiabatic approximation\nby Clotilde Fermania n-Kammerer (Université\; Paris Est - Cré\;teil Val de Marne) a s part of One world IAMP mathematical physics seminar\n\n\nAbstract\nWe wi ll discuss generalization of the quantum adiabatic theorem to a nonlinear setting. We will consider evolution equations where the Hamiltonian operat or depends on the time variable and on a finite number of parameters that are fixed on some coordinates of the unknown\, making the equation non-lin ear. Under natural spectral hypotheses\, there exist special functions tha t we call « Instantaneous nonlinear eigenvectors » such that\, in the ad iabatic limit\, the solutions of the nonlinear equations with those initia l data remain close to them\, up to a rapidly oscillating phase. We will e xplain why this question arises\, discuss the proof of this result and sho w how it can fail (works in collaboration with Alain Joye and Rémi Carles ).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/28/ END:VEVENT BEGIN:VEVENT SUMMARY:Fabio Toninelli (Technical University Vienna) DTSTART;VALUE=DATE-TIME:20210112T140000Z DTEND;VALUE=DATE-TIME:20210112T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/29 DESCRIPTION:Title: The anisotropic KPZ equation and logarithmic super-diffusivity\ nby Fabio Toninelli (Technical University Vienna) as part of One world IAM P mathematical physics seminar\n\n\nAbstract\nThe AKPZ equation is an anis otropic variant of the celebrated (two-dimensional) KPZ stochastic PDE\, w hich is expected to describe the large-scale behavior of (2+1)-dimensional growth models whose average speed of growth is a non-convex function of the average slope (AKPZ universality class). Several interacting particle systems belonging to the AKPZ class are known\, notably a class of two-dim ensional interlaced particle systems introduced by A. Borodin and P. Ferra ri. In this talk\, I will show that the non-linearity of the AKPZ equation is marginally relevant in the Renormalization Group sense: in fact\, whil e the 2d-SHE is invariant under diffusive rescaling\, for AKPZ the diffusi on coefficient diverges (logarithmically) for large times\, implying margi nal super-diffusivity. [Based on joint work with G. Cannizzaro and D. Erha rd]\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/29/ END:VEVENT BEGIN:VEVENT SUMMARY:Robert Seiringer (IST Austria) DTSTART;VALUE=DATE-TIME:20210119T140000Z DTEND;VALUE=DATE-TIME:20210119T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/30 DESCRIPTION:Title: Quantum fluctuations and dynamics of a strongly coupled polaron \nby Robert Seiringer (IST Austria) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nWe review old and new results on the Fröh lich polaron model. The discussion includes the validity of the (classical ) Landau--Pekar equations for the dynamics in the strong coupling limit\, quantum corrections to this limit\, as well as the divergence of the effec tive polaron mass.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/30/ END:VEVENT BEGIN:VEVENT SUMMARY:Margherita Disertori (University of Bonn) DTSTART;VALUE=DATE-TIME:20210302T140000Z DTEND;VALUE=DATE-TIME:20210302T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/31 DESCRIPTION:Title: Supersymmetric transfer operators\nby Margherita Disertori (Uni versity of Bonn) as part of One world IAMP mathematical physics seminar\n\ n\nAbstract\nTransfer matrix approach is a powerful tool to study one dime nsional or quasi 1d statistical mechanical models. Transfer operator kerne ls arising in the context of quantum diffusion and the supersymmetric ap proach display bosonic and fermionic components. For such kernels\, the pr esence of fermion-boson symmetries allows to drastically simplify the prob lem. I will review the method and give some results for the case of random band matrices.\n\nThis is joint work with Sasha Sodin and Martin Lohmann. \n LOCATION:https://researchseminars.org/talk/IAMP_seminars/31/ END:VEVENT BEGIN:VEVENT SUMMARY:Jan Wehr (University of Arizona) DTSTART;VALUE=DATE-TIME:20210330T140000Z DTEND;VALUE=DATE-TIME:20210330T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/32 DESCRIPTION:Title: Aggregation and deaggregation of interacting micro swimmers\nby Jan Wehr (University of Arizona) as part of One world IAMP mathematical p hysics seminar\n\n\nAbstract\nA swarm of light-sensitive robots is moving in a planar region\, changing the direction of motion randomly. Each robo t emits light\; in turn\, it adapts the speed of its motion to the total i ntensity of the light shed on it by the other robots. The adaptation take s time---the sensorial delay. Using a natural approximation of the equati ons of motion\, the robots may be programmed to make the sensorial delay n egative. In this case they are\, in some sense\, predicting the future. In a series of experiments by the Giovanni Volpe group and the University of Gothenburg (Sweden) it was shown that at a certain negative value of th e delay\, the collective behavior of the robots changes qualitatively from aggregation to deaggregation. I am going to explain this phenomenon by a n asymptotic analysis of the system of stochastic differential equations\, describing the motion of a single robot in an inhomogeneous landscape. \n \nThe results were obtained in a joint work with Giovanni Volpe\, Mite Mij alkov and Austin McDaniel. They display an interesting feature: while th e original system is driven by a single noise source\, the limiting one co ntains two independent ones. I will explain this by showing how one can g enerate two independent Wiener processes from a single one. Using this fa ct to rigorously justify the asymptotic results is a work in progress with Jeremiah Birrell.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/32/ END:VEVENT BEGIN:VEVENT SUMMARY:Jürg Fröhlich (ETH Zürich) DTSTART;VALUE=DATE-TIME:20210126T140000Z DTEND;VALUE=DATE-TIME:20210126T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/33 DESCRIPTION:Title: The Evolution of States as the Fourth Pillar of Quantum Mechanics\nby Jürg Fröhlich (ETH Zürich) as part of One world IAMP mathematica l physics seminar\n\n\nAbstract\nI present ideas about how to extend the s tandard formalism of Quantum\nMechanics in such a way that the theory actu ally makes sense. My\ntentative extension is called\n\n "ET H-Approach to Quantum Mechanics"\n\n(for "Events\, Trees and Histories").\ n\nThis approach supplies the last of four pillars QM can be constructed u pon\,\nwhich are:

\n(i) Physical quantities characteristic of a phys ical system are represented\n by self-adjoint operators\;

\n(ii) t he time evolution of these operators is given by the Heisenberg equation\;

\n(iii) meaningful notions of states and of "potential" and "actual ev ents" have\n to be introduced\; and

\n(iv) a general law for the t ime evolution of states (superseding Schroedinger\n evolution\, which is inadequate) must be formulated.\n\nBesides briefly sketching the ETH-Ap proach in the setting of non-relativistic\nQM\, I present a family of very simple models of a very heavy atom coupled to\nthe radiation field in a l imit where the speed of light tends to infinity\,\nAn analysis of these mo dels\, which illustrate the ETH Approach\, is the main\nsubject of the tal k.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/33/ END:VEVENT BEGIN:VEVENT SUMMARY:Tyler Helmuth (University of Durham) DTSTART;VALUE=DATE-TIME:20210223T140000Z DTEND;VALUE=DATE-TIME:20210223T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/34 DESCRIPTION:Title: Efficient algorithms for low-temperature spin systems\nby Tyler Helmuth (University of Durham) as part of One world IAMP mathematical phy sics seminar\n\n\nAbstract\nTwo fundamental algorithmic tasks associated t o discrete statistical mechanics models are approximate counting and appro ximate sampling. At high temperatures Markov chains give efficient algorit hms\, but at low temperatures mixing times can become impractically large\ , and Markov chain methods may fail to be efficient. Recently\, expansion methods (cluster expansions\, Pirogov--Sinai theory) have been put to use to develop provably efficient low-temperature algorithms for some discrete statistical mechanics models. I’ll introduce these algorithmic tasks\, outline how expansion algorithms work\, and indicate some open directions. \n LOCATION:https://researchseminars.org/talk/IAMP_seminars/34/ END:VEVENT BEGIN:VEVENT SUMMARY:Sylvia Serfaty (Courant Institute) DTSTART;VALUE=DATE-TIME:20210323T140000Z DTEND;VALUE=DATE-TIME:20210323T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/35 DESCRIPTION:Title: Ginzburg-Landau vortices\, old and new\nby Sylvia Serfaty (Cour ant Institute) as part of One world IAMP mathematical physics seminar\n\n\ nAbstract\nWe present a review of results on vortices in the 2D Ginzburg-L andau model of superconductivity (also relevant for superfluidity and Bose -Einstein condensates)\, their onset at critical fields\, interaction and patterns. We also report on recent joint work with Carlos Roman and Etie nne Sandier in which we study the onset of vortex lines in the 3D model an d derive an interaction energy for them.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/35/ END:VEVENT BEGIN:VEVENT SUMMARY:Søren Fournais (Aarhus University) DTSTART;VALUE=DATE-TIME:20210105T140000Z DTEND;VALUE=DATE-TIME:20210105T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/36 DESCRIPTION:Title: The ground state energy of dilute Bose gases\nby Søren Fournai s (Aarhus University) as part of One world IAMP mathematical physics semin ar\n\n\nAbstract\nThe rigorous calculation of the ground state energy of d ilute Bose gases has been a challenging problem since the 1950s. In partic ular\, it is of interest to understand the extent to which the Bogoliubov pairing theory correctly describes the ground state of this physical syste m.\nIn this talk I will report on a recent proof of the second term in the energy expansion for dilute gases\, the so-called Lee-Huang-Yang term\, a nd its relation to Bogoliubov theory.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/36/ END:VEVENT BEGIN:VEVENT SUMMARY:Wei Wu (NYU Shanghai) DTSTART;VALUE=DATE-TIME:20210202T140000Z DTEND;VALUE=DATE-TIME:20210202T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/37 DESCRIPTION:Title: Massless phases for the Villain model in $d \\geq 3$\nby Wei Wu (NYU Shanghai) as part of One world IAMP mathematical physics seminar\n\n \nAbstract\nThe XY and the Villain models are mathematical idealization of real world models of liquid crystal\, liquid helium\, and superconductors . Their phase transition has important applications in condensed matter ph ysics and led to the Nobel\nPrize in Physics in 2016. However we are still far from a complete mathematical\nunderstanding of the transition. The sp in wave conjecture\, originally proposed by Dyson and by Mermin and Wagner \, predicts that at low temperature\, large scale behaviors of these model s are closely related to Gaussian free fields. I will review the historica l background and discuss some recent progress on this conjecture in $d \\g eq 3$.\nBased on the joint work with Paul Dario (Tel Aviv).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/37/ END:VEVENT BEGIN:VEVENT SUMMARY:Gianluca Panati (University of Rome Sapienza) DTSTART;VALUE=DATE-TIME:20210316T140000Z DTEND;VALUE=DATE-TIME:20210316T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/38 DESCRIPTION:Title: The Localization Dichotomy in Solid State Physics\nby Gianluca Panati (University of Rome Sapienza) as part of One world IAMP mathematica l physics seminar\n\n\nAbstract\nSolid state systems exhibit a subtle inte rtwining between the topology of the\n"manifold" of occupied states and th e localization of electrons\, if the latter is appropriately defined. \n

\ni) either there exists an exponentially localized CWB\ , and correspondingly the Chern \nclass of $P_F$ vanishes (ordinary insula tor)\;

\nii) or

\nMore recently\, the previous dichotomy has been reformulated in such a way that it applies\nalso to non-periodic systems\, and a corres ponding "Localization Dichotomy conjecture" for\nnon-periodic systems has been stated. \n

\nIn my talk\, I will gently introduce the subject\, st arting from the periodic case\, and summarize the \nrecent attempts\, by s everal groups\, to prove the Localization Dichotomy for non-periodic syste ms. \n

\nThe talk is based on work in collaboration with D. Monaco\, M. Marcelli\, M. Moscolari\, \nA. Pisante\, and S. Teufel\, and on discussio ns with several colleagues.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/38/ END:VEVENT BEGIN:VEVENT SUMMARY:Gerald Dunne (University of Connecticut) DTSTART;VALUE=DATE-TIME:20210216T140000Z DTEND;VALUE=DATE-TIME:20210216T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/39 DESCRIPTION:Title: Resurgent Asymptotics and Non-perturbative Physics\nby Gerald D unne (University of Connecticut) as part of One world IAMP mathematical ph ysics seminar\n\n\nAbstract\nThere are several important conceptual and co mputational questions concerning path integrals\, which have recently been approached from new perspectives motivated by Ecalle's theory of resurgen t functions\, a mathematical formalism that unifies perturbative and non-p erturbative physics. I will review the basic ideas behind the connections between resurgent asymptotics and physics\, with examples from quantum mec hanics and matrix models.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/39/ END:VEVENT BEGIN:VEVENT SUMMARY:Herbert Spohn (TU Munich) DTSTART;VALUE=DATE-TIME:20210209T140000Z DTEND;VALUE=DATE-TIME:20210209T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/40 DESCRIPTION:Title: Generalised hydrodynamics of the Toda lattice\nby Herbert Spohn (TU Munich) as part of One world IAMP mathematical physics seminar\n\nAbs tract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/40/ END:VEVENT BEGIN:VEVENT SUMMARY:Simone Warzel (TU Munich) DTSTART;VALUE=DATE-TIME:20210309T140000Z DTEND;VALUE=DATE-TIME:20210309T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/41 DESCRIPTION:Title: An invitation to quantum spin glasses\nby Simone Warzel (TU Mun ich) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\ nQuantum spin glass models of mean-field type are prototypes of quantum sy stems exhibiting phase transitions related to the spead of the eigenstates in configuration space. \nOriginally motivated by spin glass physics\, t hey are discussed in relation to many-body localisation phenomena\, quantu m adiabatic algorithms as well as in the context of models in mathematical biology. \nQuantum effects transform the rich phase diagram of classical spin glasses as described by Parisi’s theory into an even more colourful landscape of phases which range from purely quantum paramagnetic to inter mediate behavior in which eigenstates occupy only a fraction of configurat ion space.\n\nIn this talk\, I will give an introduction to the multifacet ed motivations and challenges behind the study of these quantum glasses an d explain existing and expected results.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/41/ END:VEVENT BEGIN:VEVENT SUMMARY:Wojciech De Roeck (KU Leuven) DTSTART;VALUE=DATE-TIME:20210413T140000Z DTEND;VALUE=DATE-TIME:20210413T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/42 DESCRIPTION:Title: Impurities and boundaries for a class of gapped ground states\n by Wojciech De Roeck (KU Leuven) as part of One world IAMP mathematical ph ysics seminar\n\n\nAbstract\nIn the last two decades\, a lot of rigorous r esults have been proven for quantum ground states protected by a spectral gap in their Hamiltonian. Think for example of decay of correlations\, the topological classification of states\, and area laws of entanglement.\nFo r all of those results\, the spectral gap is a necessary input\, both on t he conceptual and on the technical level. \nImagine now that we consider s uch a gapped Hamiltonian that is perturbed locally by a term that is not s mall\, such that we certainly cannot hope to preserve the global gap. Comm on sense dictates that\, far away from the perturbation\, the ground state should not be seriously affected by this perturbation. \nWhile we cannot prove this in the generality in which it should be true\, I will describe some results that go in this direction.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/42/ END:VEVENT BEGIN:VEVENT SUMMARY:Eric Carlen (Rutgers University) DTSTART;VALUE=DATE-TIME:20210420T140000Z DTEND;VALUE=DATE-TIME:20210420T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/43 DESCRIPTION:Title: Kac Master Equations\, Classical and Quantum\nby Eric Carlen (R utgers University) as part of One world IAMP mathematical physics seminar\ n\n\nAbstract\nThis lecture will review recent progress and open problems concerning Kac Master Equations in both the classical and quantum setting. It will be based largely on recent papers written in collaboration with M aria Carvalho\, Michael Loss and Bernt Wennberg.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/43/ END:VEVENT BEGIN:VEVENT SUMMARY:Bernard Helffer (Paris-Sud / Nantes) DTSTART;VALUE=DATE-TIME:20210406T140000Z DTEND;VALUE=DATE-TIME:20210406T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/44 DESCRIPTION:Title: Semiclassical methods and tunneling effects: old and new\nby Be rnard Helffer (Paris-Sud / Nantes) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nIn 1982-1983 the so-called symmetric doubl e well problem was rigorously analyzed in any dimension in the semi-classi cal context by B. Simon and Helffer-Sjöstrand.\nThis involves semi-clas sical Agmon estimates\, Harmonic approximation\, WKB constructions and a v ery fine analysis of the so-called tunneling effect in order to establish the splitting between the lowest eigenvalues.\n\nThe strategy followed by Helffer-Sjöstrand appears to be quite efficient in many other contexts. After recalling how it works on the initial double well problem\,\nwe will discuss in a rather impressionist way the main successes of the approach along the years.\nFinally we will focus on a quite recent result by Bonna illie-Hérau-Raymond devoted to the measure of a magnetic tunneling in Sur face Superconductivity and discuss open problems.\n\nThe presented results correspond to contributions by various subsets of the following set of au thors : Bonnaillie\, Fournais\, Helffer\, Hérau\, Kachmar\, Morame\, Nier \,\nRaymond\, Simon\, Sjöstrand and many others...\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/44/ END:VEVENT BEGIN:VEVENT SUMMARY:Sabine Jansen (LMU Munich) DTSTART;VALUE=DATE-TIME:20210427T140000Z DTEND;VALUE=DATE-TIME:20210427T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/45 DESCRIPTION:Title: Virial expansion for mixtures: some examples & recent results\n by Sabine Jansen (LMU Munich) as part of One world IAMP mathematical physi cs seminar\n\n\nAbstract\nMayer's expansion is an expansion of the pressur e in powers of the activity (fugacity) in equilibrium statistical mechanic s\; the virial expansion is an expansion in powers of the density. Rigorou s convergence results have been available for decades\, nevertheless for m ixtures the theory of density expansions is less advanced than the theory of activity expansions. I will review the setting\, and discuss some recen t results for the virial expansion for mixtures (multi-species systems) an d illustrate them with three concrete models: mixtures of hard spheres of different sizes\, non-overlapping rods of different lengths\, and a hierar chical mixture of cubes in $Z^d$. The last two examples are helpful toy mo dels for which concrete formulas are available and phase transitions can b e studied. Based in part on joint works with Tobias Kuna\, Stephen Tate\, Dimitrios Tsagkarogiannis and Daniel Ueltschi.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/45/ END:VEVENT BEGIN:VEVENT SUMMARY:David Brydges (University of British Columbia) DTSTART;VALUE=DATE-TIME:20210511T140000Z DTEND;VALUE=DATE-TIME:20210511T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/46 DESCRIPTION:Title: Lace expansions and spin models\nby David Brydges (University o f British Columbia) as part of One world IAMP mathematical physics seminar \n\n\nAbstract\nI will review lace expansions starting with their\nrelatio n to the other expansions in statistical mechanics and then\ndiscussing th eir application to spin models. Akira Sakai opened\nthis avenue in 2007 wi th his proof that in sufficiently high dimension\n$d$ the two point functi on for the critical Ising model is asymptotic\nto $c_d |x-y|^{-(d-2)}$. I n arxiv.org/abs/1905.09605 Tyler\nHelmuth\, Mark Holmes and I have introduced a different way to deri ve\nlace expansions based on the Symanzik random walk representation.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/46/ END:VEVENT BEGIN:VEVENT SUMMARY:Marcel Griesemer (University of Stuttgart) DTSTART;VALUE=DATE-TIME:20210518T140000Z DTEND;VALUE=DATE-TIME:20210518T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/47 DESCRIPTION:Title: From Short-Range to Contact Interactions in Many-Body Quantum Syste ms\nby Marcel Griesemer (University of Stuttgart) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nMany-body quantum system s with short-ranged two-body interactions\, such as ultracold quantum gase s are often described by simplified models with contact interactions (some times called delta-potentials). The merit of such models is their simplici ty\, solvability (to some extent) and lack of irrelevant or unknown detail . They are also toy models of renormalization. On the other hand\, in dime nsions $d\\geq 2$ contact interactions are not small perturbations of the free energy\, which makes their self adjoint implementation in the case of $N>2$ particles a subtle business. This talk gives an introduction to the mathematics of many-particle quantum systems with two-body contact intera ctions and their approximation by Schrödinger operators.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/47/ END:VEVENT BEGIN:VEVENT SUMMARY:Constanza Rojas-Molina (Cergy Paris University) DTSTART;VALUE=DATE-TIME:20210525T140000Z DTEND;VALUE=DATE-TIME:20210525T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/48 DESCRIPTION:Title: Fractional random Schrödinger operators\, integrated density of st ates and localization\nby Constanza Rojas-Molina (Cergy Paris Universi ty) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\n We will review some recent results on the fractional Anderson model\, a ra ndom Schrödinger operator driven by a fractional laplacian. The interest of the latter lies in its association to stable Levy processes\, random wa lks with long jumps and anomalous diffusion. We discuss the interplay betw een the non-locality of the fractional laplacian and the localization prop erties of the random potential in the fractional Anderson model\, in both the continuous and discrete settings. In the discrete setting we study the integrated density of states and show a fractional version of Lifshitz ta ils. This coincides with results obtained in the continuous setting by the probability community. This talk is based on joint work with M. Gebert (L MU Munich).\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/48/ END:VEVENT BEGIN:VEVENT SUMMARY:Chris Fewster (University of York) DTSTART;VALUE=DATE-TIME:20210504T140000Z DTEND;VALUE=DATE-TIME:20210504T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/49 DESCRIPTION:Title: Measurement of quantum fields in curved spacetimes\nby Chris Fe wster (University of York) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nA standard account of the measurement chain in quan tum mechanics involves a probe (itself a quantum system) coupled temporari ly to the system of interest. Once the coupling is removed\, the probe is measured and the results are interpreted as the measurement of a system ob servable. Measurement schemes of this type have been studied extensively i n Quantum Measurement Theory\, but they are rarely discussed in the contex t of quantum fields and still less on curved spacetimes. \n\nIn this talk I will describe how measurement schemes may be formulated for quantum fiel ds on curved spacetime within the general setting of algebraic QFT. In par ticular\, I will show how measurements of probe observables correspond to measurements of "induced" local system observables and describe the role o f state update rules. The framework is local and fully covariant\, allowin g the consistent description of measurements made in spacelike separated r egions. Furthermore\, specific models can be given in which the framework may be exemplified by concrete calculations. I will also explain how this framework can shed light on an old problem due to Sorkin concerning "impos sible measurements" in which measurement apparently conflicts with causali ty. Finally\, I will discuss new results indicating that the system observ ables that can be induced by measurement schemes form a large subspace of the algebra of all local observables.\n\nThe talk is based on work with Ra iner Verch [Leipzig]\, (Comm. Math. Phys. 378\, 851–889(2020)\, arXiv:18 10.06512\; see also arXiv:1904.06944 for a summary)\, with Henning Bostelm ann and Maximilian Ruep [York] ( Phys. Rev. D 103 (2021) 025017\; arXiv:20 03.04660) and work in progress with Ian Jubb [Dublin] and Maximilian Ruep. \n LOCATION:https://researchseminars.org/talk/IAMP_seminars/49/ END:VEVENT BEGIN:VEVENT SUMMARY:Benjamin Schlein (University of Zürich) DTSTART;VALUE=DATE-TIME:20210601T140000Z DTEND;VALUE=DATE-TIME:20210601T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/50 DESCRIPTION:Title: Correlation energy of weakly interacting Fermi gases\nby Benjam in Schlein (University of Zürich) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nWe consider Fermi gases in a mean-field reg ime. To leading order\, the ground state energy is given by Hartree-Fock t heory. The correction to the Hartree-Fock energy\, produced by the many-bo dy interaction\, is known as correlation energy. In this talk\, we obtain a formula for the correlation energy\, based on the observation that\, ene rgetically\, the main excitations of the Fermi sea are particle-hole pairs that behave\, approximately\, as bosons and can therefore be dealt with t hrough (bosonic) Bogoliubov theory. The talk is based on joint works with N. Benedikter\, P.T. Nam\, M. Porta and R. Seiringer.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/50/ END:VEVENT BEGIN:VEVENT SUMMARY:Laszlo Erdös (IST Austria) DTSTART;VALUE=DATE-TIME:20210608T140000Z DTEND;VALUE=DATE-TIME:20210608T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/51 DESCRIPTION:Title: Eigenstate thermalisation hypothesis and Gaussian fluctuations for Wigner matrices\nby Laszlo Erdös (IST Austria) as part of One world I AMP mathematical physics seminar\n\n\nAbstract\nWe prove that any determi nistic matrix is approximately\nthe identity in the eigenbasis of a large random Wigner matrix W\nwith an optimal error inversely proportional to th e square root of the dimension.\nThis verifies a strong form of Quantum U nique Ergodicity \nwith an optimal convergence rate and we also prove Gaus sian fluctuations\naround this convergence.\nThe key technical tool is a n ew multi-resolvent local law for Wigner\nensemble and the Dyson Brownian m otion for eigenvector overlaps.\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/51/ END:VEVENT BEGIN:VEVENT SUMMARY:Gordon Slade (UBC Vancouver) DTSTART;VALUE=DATE-TIME:20210615T140000Z DTEND;VALUE=DATE-TIME:20210615T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/52 DESCRIPTION:Title: Mean-field tricritical polymers\nby Gordon Slade (UBC Vancouver ) as part of One world IAMP mathematical physics seminar\n\n\nAbstract\nWe provide a full description of a tricritical phase diagram in the setting of a mean-field random walk model of a polymer density transition. The mod el involves a continuous-time random walk on the complete graph in the lim it as the number of vertices N in the graph grows to infinity. The walk ha s a repulsive self-interaction\, as well as a competing attractive self-in teraction whose strength is controlled by a parameter g. A chemical potent ial ν controls the walk length. We determine the phase diagram in the (g\ ,ν) plane\, as a model of a density transition for a single linear polyme r chain. The proof uses a supersymmetric representation for the random wal k model\, followed by a single block-spin renormalisation group step to re duce the problem to a 1-dimensional integral\, followed by application of the Laplace method for an integral with a large parameter. The talk is bas ed on joint work with Roland Bauerschmidt\, Probability and Mathematical P hysics 1\, 167-204 (2020)\; arXiv:1911.00395 .\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/52/ END:VEVENT BEGIN:VEVENT SUMMARY:Clément Tauber (University of Strasbourg) DTSTART;VALUE=DATE-TIME:20210622T140000Z DTEND;VALUE=DATE-TIME:20210622T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/53 DESCRIPTION:by Clément Tauber (University of Strasbourg) as part of One w orld IAMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/53/ END:VEVENT BEGIN:VEVENT SUMMARY:Mathieu Lewin (Paris Dauphine University) DTSTART;VALUE=DATE-TIME:20210629T140000Z DTEND;VALUE=DATE-TIME:20210629T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/54 DESCRIPTION:by Mathieu Lewin (Paris Dauphine University) as part of One wo rld IAMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/54/ END:VEVENT BEGIN:VEVENT SUMMARY:Nikolaos Zygouras (University of Warwick) DTSTART;VALUE=DATE-TIME:20210706T140000Z DTEND;VALUE=DATE-TIME:20210706T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/55 DESCRIPTION:by Nikolaos Zygouras (University of Warwick) as part of One wo rld IAMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/55/ END:VEVENT BEGIN:VEVENT SUMMARY:Mark Malamud (RUDN University) DTSTART;VALUE=DATE-TIME:20210713T140000Z DTEND;VALUE=DATE-TIME:20210713T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/56 DESCRIPTION:by Mark Malamud (RUDN University) as part of One world IAMP ma thematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/56/ END:VEVENT BEGIN:VEVENT SUMMARY:Phan Thành Nam (LMU Munich) DTSTART;VALUE=DATE-TIME:20210720T140000Z DTEND;VALUE=DATE-TIME:20210720T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/57 DESCRIPTION:by Phan Thành Nam (LMU Munich) as part of One world IAMP math ematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/57/ END:VEVENT BEGIN:VEVENT SUMMARY:Eveliina Peltola (University of Bonn) DTSTART;VALUE=DATE-TIME:20210727T140000Z DTEND;VALUE=DATE-TIME:20210727T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/58 DESCRIPTION:by Eveliina Peltola (University of Bonn) as part of One world IAMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/58/ END:VEVENT BEGIN:VEVENT SUMMARY:Antti Knowles (University of Geneva) DTSTART;VALUE=DATE-TIME:20210831T140000Z DTEND;VALUE=DATE-TIME:20210831T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/59 DESCRIPTION:by Antti Knowles (University of Geneva) as part of One world I AMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/59/ END:VEVENT BEGIN:VEVENT SUMMARY:Pierre Germain (New York University) DTSTART;VALUE=DATE-TIME:20210907T140000Z DTEND;VALUE=DATE-TIME:20210907T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/60 DESCRIPTION:by Pierre Germain (New York University) as part of One world I AMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/60/ END:VEVENT BEGIN:VEVENT SUMMARY:Daniela Cadamuro (University of Leipzig) DTSTART;VALUE=DATE-TIME:20210810T140000Z DTEND;VALUE=DATE-TIME:20210810T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/61 DESCRIPTION:by Daniela Cadamuro (University of Leipzig) as part of One wor ld IAMP mathematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/61/ END:VEVENT BEGIN:VEVENT SUMMARY:Ron Peled (Tel Aviv University) DTSTART;VALUE=DATE-TIME:20210824T140000Z DTEND;VALUE=DATE-TIME:20210824T150000Z DTSTAMP;VALUE=DATE-TIME:20210612T234149Z UID:IAMP_seminars/62 DESCRIPTION:by Ron Peled (Tel Aviv University) as part of One world IAMP m athematical physics seminar\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/IAMP_seminars/62/ END:VEVENT END:VCALENDAR