BEGIN:VCALENDAR
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BEGIN:VEVENT
SUMMARY:Luca Tamanini (Universite Paris Dauphine)
DTSTART:20210621T150000Z
DTEND:20210621T154000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/1
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/1/">Small-time asymptotics of the metric Schrödinger problem</a>\
 nby Luca Tamanini (Universite Paris Dauphine) as part of BIRS workshop: En
 tropic Regularization of Optimal Transport and Applications\n\n\nAbstract\
 nThe Schrödinger problem as "noised" optimal transport is by now a well-e
 stablished interpretation. From this perspective several natural questions
  stem\, as for instance the convergence rate as the noise parameter vanish
 es of many quantities: optimal value\, Schrödinger bridges and potentials
 ... As for the optimal value\, after the works of Erbar-Maas-Renger and Pa
 l a first-order Taylor expansion is available.  First aim of this talk is 
 to improve this result in a twofold sense: from the first to the second or
 der and from the Euclidean to the Riemannian setting (and actually far bey
 ond). From the proof it will be clear that the statement is in fact a part
 icular instance of a more general result. For this reason\, in the second 
 part of the talk we introduce a large class of dynamical variational probl
 ems\, extending far beyond the classical Schrödinger problem\, and for th
 em we prove $\\Gamma$-convergence towards the geodesic problem and a suita
 ble generalization of the second-order Taylor expansion.  (based on joint 
 works with G. Conforti\, L. Monsaingeon and D. Vorotnikov)\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Luca Nenna (Université Paris-Saclay)
DTSTART:20210621T155000Z
DTEND:20210621T163000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/2
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/2/">From Schrödinger to Lasry-Lions</a>\nby Luca Nenna (Universit
 é Paris-Saclay) as part of BIRS workshop: Entropic Regularization of Opti
 mal Transport and Applications\n\n\nAbstract\nThe minimization of a relati
 ve entropy (with respect to the Wiener measure) is a very old problem whic
 h dates back to Schrödinger. C. Léonard has established strong connectio
 ns and analogies between this problem and the Monge-Kantorovich problem wi
 th quadratic cost (namely the standard Optimal Transport problem). In part
 icular\, the entropic interpolation leads to a system of PDEs which presen
 t strong analogies with the Mean Field Game system with a quadratic Hamilt
 onian. In this talk\, we will explain how such systems can indeed be obtai
 ned by minimization of a relative entropy at the level of measures on path
 s with an additional term involving the marginal in time. If time permitte
 d we will also show the multi-population case and its connection with some
  equations in Quantum Mechanics.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Young-Heon Kim (University of British Columbia)
DTSTART:20210621T164000Z
DTEND:20210621T172000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/3
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/3/">Optimal transport in Brownian motion stopping</a>\nby Young-He
 on Kim (University of British Columbia) as part of BIRS workshop: Entropic
  Regularization of Optimal Transport and Applications\n\n\nAbstract\nWe co
 nsider an optimal transport problem arising from stopping the Brownian mot
 ion from a given distribution to get a fixed or free target distribution\;
  the fixed target case is often called the optimal Skorokhod embedding pro
 blem in the literature\, a popular topic in math finance pioneered by many
  people. Our focus is on the case of general dimensions\, which has not be
 en well understood. We explain that under certain natural assumptions on t
 he transportation cost\, the optimal stopping time is given by the hitting
  time to a barrier\, which is determined by the solution to the dual optim
 ization problem. In the free target case\, the problem is related to the S
 tefan problem\, that is\, a free boundary problem for the heat equation. W
 e obtain analytical information on the optimal solutions\, including certa
 in BV estimates. The fixed target case is mainly from the joint work with 
 Nassif Ghoussoub and Aaron Palmer at UBC\, while the free target case is t
 he recent joint work (in-progress) with Inwon Kim at UCLA.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robert McCann (University of Toronto)
DTSTART:20210621T173000Z
DTEND:20210621T181000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/4
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/4/">Inscribed radius bounds for lower Ricci bounded metric measure
  spaces with mean convex boundary</a>\nby Robert McCann (University of Tor
 onto) as part of BIRS workshop: Entropic Regularization of Optimal Transpo
 rt and Applications\n\n\nAbstract\nInscribed radius bounds for lower Ricci
  bounded metricConsider an essentially nonbranching metric measure space w
 ith the measure contraction property of Ohta and Sturm. We prove a sharp u
 pper bound on the inscribed radius of any subset whose boundary has a suit
 ably signed lower bound on its generalized mean curvature. This provides a
  nonsmooth analog of results dating back to Kasue (1983) and subsequent au
 thors. We prove a stability statement concerning such bounds and --- in th
 e Riemannian curvature-dimension (RCD) setting --- characterize the cases 
 of equality. This represents joint work with Annegret Burtscher\, Christia
 n Ketterer and Eric Woolgar.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yongxin Chen (Georgia Tech)
DTSTART:20210621T203000Z
DTEND:20210621T211000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/5
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/5/">Graphical Optimal Transport and its Applications</a>\nby Yongx
 in Chen (Georgia Tech) as part of BIRS workshop: Entropic Regularization o
 f Optimal Transport and Applications\n\n\nAbstract\nMulti-marginal optimal
  transport (MOT) is a generalization of optimal transport theory to settin
 gs with possibly more than two marginals. The computation of the solutions
  to MOT problems has been a longstanding challenge. In this talk\, we intr
 oduce graphical optimal transport\, a special class of MOT problems. We co
 nsider MOT problems from a probabilistic graphical model perspective and p
 oint out an elegant connection between the two when the underlying cost fo
 r optimal transport allows a graph structure. In particular\, an entropy r
 egularized MOT is equivalent to a Bayesian marginal inference problem for 
 probabilistic graphical models with the additional requirement that some o
 f the marginal distributions are specified. This relation on the one hand 
 extends the optimal transport as well as the probabilistic graphical model
  theories\, and on the other hand leads to fast algorithms for MOT by leve
 raging the well-developed algorithms in Bayesian inference. We will cover 
 recent developments of graphical optimal transport in theory and algorithm
 s. We will also go over several applications in aggregate filtering and me
 an field games.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriel Peyré (CNRS and Ecole Normale Supérieure)
DTSTART:20210622T150000Z
DTEND:20210622T154000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/6
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/6/">Scaling Optimal Transport for High dimensional Learning</a>\nb
 y Gabriel Peyré (CNRS and Ecole Normale Supérieure) as part of BIRS work
 shop: Entropic Regularization of Optimal Transport and Applications\n\n\nA
 bstract\nOptimal transport (OT) has recently gained lot of interest in mac
 hine learning. It is a natural tool to compare in a geometrically faithful
  way probability distributions. It finds applications in both supervised l
 earning (using geometric loss functions) and unsupervised learning (to per
 form generative model fitting). OT is however plagued by the curse of dime
 nsionality\, since it might require a number of samples which grows expone
 ntially with the dimension. In this talk\, I will explain how to leverage 
 entropic regularization methods to define computationally efficient loss f
 unctions\, approximating OT with a better sample complexity. More informat
 ion and references can be found on the website of our book "Computational 
 Optimal Transport" https://optimaltransport.github.io/\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Korba (École Nationale de la Statistique et de l'Administrat
 ion Économique)
DTSTART:20210622T155000Z
DTEND:20210622T163000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/7
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/7/">Wasserstein Proximal Gradient</a>\nby Anna Korba (École Natio
 nale de la Statistique et de l'Administration Économique) as part of BIRS
  workshop: Entropic Regularization of Optimal Transport and Applications\n
 \n\nAbstract\nWasserstein gradient flows are continuous time dynamics that
  define curves of steepest descent to minimize an objective function over 
 the space of probability measures (i.e.\, the Wasserstein space). This obj
 ective is typically a divergence w.r.t. a fixed target distribution. In re
 cent years\, these continuous time dynamics have been used to study the co
 nvergence of machine learning algorithms aiming at approximating a probabi
 lity distribution. However\, the discrete-time behavior of these algorithm
 s might differ from the continuous time dynamics. Besides\, although discr
 etized gradient flows have been proposed in the literature\, little is kno
 wn about their minimization power. In this work\, we propose a Forward Bac
 kward (FB) discretization scheme that can tackle the case where the object
 ive function is the sum of a smooth and a nonsmooth geodesically convex te
 rms. Using techniques from convex optimization and optimal transport\, we 
 analyze the FB scheme as a minimization algorithm on the Wasserstein space
 . More precisely\, we show under mild assumptions that the FB scheme has c
 onvergence guarantees similar to the proximal gradient algorithm in Euclid
 ean spaces.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jonathan Niles-Weed (New York University)
DTSTART:20210622T164000Z
DTEND:20210622T172000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/8
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/8/">Asymptotics for semi-discrete entropic optimal transport</a>\n
 by Jonathan Niles-Weed (New York University) as part of BIRS workshop: Ent
 ropic Regularization of Optimal Transport and Applications\n\nAbstract: TB
 A\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zaid Harchaoui
DTSTART:20210622T173000Z
DTEND:20210622T181000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/9
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/9/">chrödinger Bridge with Entropic Regularization: two-sample te
 st\, chaos decomposition\, and large-sample limits</a>\nby Zaid Harchaoui 
 as part of BIRS workshop: Entropic Regularization of Optimal Transport and
  Applications\n\n\nAbstract\nWe consider an entropy-regularized statistic 
 that allows one to compare two data samples drawn from possibly different 
 distributions. The statistic admits an expression as a weighted average of
  Monge couplings with respect to a Gibbs measure. This coupling can be rel
 ated to the static Schrödinger bridge given a finite number of particles.
  We establish the asymptotic consistency as the sample sizes go to infinit
 y of the statistic and show that the population limit is the solution of F
 öllmer's entropy-regularized optimal transport. The proof technique relie
 s on a chaos decomposition for paired samples. This is joint work with Lan
 g Liu and Soumik Pal.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Promit Ghosal (MIT)
DTSTART:20210622T203000Z
DTEND:20210622T211000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/10
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/10/">Geometry and large deviation of entropic optimal transport</a
 >\nby Promit Ghosal (MIT) as part of BIRS workshop: Entropic Regularizatio
 n of Optimal Transport and Applications\n\n\nAbstract\nOptimal transport (
 OT) theory has flourished due to its connections with geometry\, analysis\
 , probability theory\, and other fields in mathematics. A renewed interest
  in OT stems from applied fields such as machine learning\, image processi
 ng and statistics through the introduction of entropic regularization. In 
 this talk\, we will discuss the convergence of entropically regularized op
 timal transport.  Our first result is about a large deviation principle of
  the associated optimizers in entropic OT and the second result is about t
 he stability of the optimizers under weak convergence. To prove these resu
 lts\, we will introduce  a new notion called 'cyclical invariance' of meas
 ures.  This is a joint work with Marcel Nutz and Espen Bernton.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Beatrice Acciaio (ETH Zürich)
DTSTART:20210623T150000Z
DTEND:20210623T154000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/11
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/11/">PQ-GAN: a market generation model consistent with observed sp
 ot prices and derivative price</a>\nby Beatrice Acciaio (ETH Zürich) as p
 art of BIRS workshop: Entropic Regularization of Optimal Transport and App
 lications\n\n\nAbstract\nOptimal transport (OT) theory has flourished due 
 to its connections with geometry\, analysis\, probability theory\, and oth
 er fields in mathematics. A renewed interest in OT stems from applied fiel
 ds such as machine learning\, image processing and statistics through the 
 introduction of entropic regularization. In this talk\, we will discuss th
 e convergence of entropically regularized optimal transport.  Our first re
 sult is about a large deviation principle of the associated optimizers in 
 entropic OT and the second result is about the stability of the optimizers
  under weak convergence. To prove these results\, we will introduce  a new
  notion called 'cyclical invariance' of measures.  This is a joint work wi
 th Marcel Nutz and Espen Bernton.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alfred Galichon (New York University)
DTSTART:20210623T155000Z
DTEND:20210623T163000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/12
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/12/">Dynamic Matching Problems (joint w Pauline Corblet and Jeremy
  Fox)</a>\nby Alfred Galichon (New York University) as part of BIRS worksh
 op: Entropic Regularization of Optimal Transport and Applications\n\n\nAbs
 tract\nFor the purposes of economics applications\, we formulate a class o
 f dynamic matching problems. We investigate in particular the stationary c
 ase\, and computation and estimation issues are investigated.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ting-Kam Leonard Wong (University of Toronto)
DTSTART:20210623T164000Z
DTEND:20210623T172000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/13
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/13/">Logarithmic divergences and statistical applications</a>\nby 
 Ting-Kam Leonard Wong (University of Toronto) as part of BIRS workshop: En
 tropic Regularization of Optimal Transport and Applications\n\n\nAbstract\
 nWe consider the Dirichlet optimal transport which is a multiplicative ana
 logue of the Wasserstein transport and is deeply connected to the Dirichle
 t distribution. The log-likelihood of this distribution defines a logarith
 mic divergence\, in the same way that the square loss comes from the norma
 l distribution. Using this divergence\, which can be extended to a family 
 of generalized exponential families\, we consider statistical methodologie
 s including clustering and nonlinear principal component analysis. Our app
 roach extends a well-known duality between exponential family and Bregman 
 divergence. Joint work with Zhixu Tao\, Jiaowen Yang and Jun Zhang.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Martin Huesmann (Universität Münster)
DTSTART:20210624T150000Z
DTEND:20210624T154000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/14
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/14/">Fluctuations in the optimal matching problems</a>\nby Martin 
 Huesmann (Universität Münster) as part of BIRS workshop: Entropic Regula
 rization of Optimal Transport and Applications\n\n\nAbstract\nThe optimal 
 matching problem is one of the classical random optimization problems. Whi
 le the asymptotic behavior of the expected cost is well understood only li
 ttle is known for the asymptotic behavior of the optimal couplings - the s
 olutions to the optimal matching problem. In this talk we show that at all
  mesoscopic scales the displacement under the optimal coupling converges i
 n suitable Sobolev spaces to a Gaussian field which can be identified as t
 he curl-free part of a vector Gaussian free field.  (based on joint work w
 ith Michael Goldman)\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mathias Beiglböck (University of Vienna)
DTSTART:20210624T155000Z
DTEND:20210624T163000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/15
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/15/">The Wasserstein space of stochastic processes</a>\nby Mathias
  Beiglböck (University of Vienna) as part of BIRS workshop: Entropic Regu
 larization of Optimal Transport and Applications\n\n\nAbstract\nWasserstei
 n distance induces a natural Riemannian structure for the probabilities on
  the Euclidean space. This insight of classical transport theory is fundam
 ental for tremendous applications in various fields of pure and applied ma
 thematics. We believe that an appropriate probabilistic variant\, the adap
 ted Wasserstein distance AW\, can play a similar role for the class FP of 
 filtered processes\, i.e. stochastic processes together with a filtration.
  In contrast to other topologies for stochastic processes\, probabilistic 
 operations such as the Doob-decomposition\, optimal stopping and stochasti
 c control are continuous w.r.t. AW. We also show that (FP\,AW) is a geodes
 ic space\, isometric to a classical Wasserstein space\, and that martingal
 es form a closed geodesically convex subspace.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Kausamo
DTSTART:20210624T164000Z
DTEND:20210624T172000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/16
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/16/">Multi-marginal entropy-regularized optimal transportation for
  singular cost functions</a>\nby Anna Kausamo as part of BIRS workshop: En
 tropic Regularization of Optimal Transport and Applications\n\n\nAbstract\
 nI will introduce multi-marginal optimal transportation (MOT) for singular
  cost functions and mention some of its applications. Then I move on to th
 e entropy-regularised framework\, focusing on the Gamma-convergence proof 
 of the regularized minimizers for the singular MOT problem towards a non-r
 egularised solution when the regularisation parameter goes to zero. When o
 ne goes from two to many marginals and from attractive to singular cost fu
 nction\, different levels of difficulty are introduced. One of the aims of
  my talk is to show how these difficulties can be tackled.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Giovanni Conforti (Ecole Polytechnique Paris – Mathematics)
DTSTART:20210624T173000Z
DTEND:20210624T181000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/17
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/17/">Hamilton Jacobi equations for controlled gradient flows: the 
 comparison principle</a>\nby Giovanni Conforti (Ecole Polytechnique Paris 
 – Mathematics) as part of BIRS workshop: Entropic Regularization of Opti
 mal Transport and Applications\n\n\nAbstract\nThis talk is devoted to the 
 study of a class of  Hamilton-Jacobi equations on the space of probability
  measures that arises naturally in connection with the study of a general 
 form of the Schrödinger problem for interacting particle systems.  After 
 presenting the equations and their geometrical interpretation\, I will mov
 e on to illustrate the main ideas behind a general strategy for to prove u
 niqueness of viscosity solutions\, i.e. the comparison principle. Joint wo
 rk with D.Tonon (U. Padova) and R.Kraaij (TU Delft).\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Geoffrey Schiebinger (University of British Columbia)
DTSTART:20210624T203000Z
DTEND:20210624T211000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/18
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/18/">Towards a mathematical theory of development</a>\nby Geoffrey
  Schiebinger (University of British Columbia) as part of BIRS workshop: En
 tropic Regularization of Optimal Transport and Applications\n\n\nAbstract\
 nNew measurement technologies like single-cell RNA sequencing are bringing
  'big data' to biology. My group develops mathematical tools for analyzing
  time-courses of high-dimensional gene expression data\, leveraging tools 
 from probability and optimal transport. We aim to develop a mathematical t
 heory to answer questions like How does a stem cell transform into a muscl
 e cell\, a skin cell\, or a neuron? How can we reprogram a skin cell into 
 a neuron?  We model a developing population of cells with a curve in the s
 pace of probability distributions on a high-dimensional gene expression sp
 ace. We design algorithms to recover these curves from samples at various 
 time-points and we collaborate closely with experimentalists to test these
  ideas on real data.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Max von Renesse (Universitaet Leipzig)
DTSTART:20210625T150000Z
DTEND:20210625T154000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/19
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/19/">On Overrelaxation in the Sinkhorn Algorithm</a>\nby Max von R
 enesse (Universitaet Leipzig) as part of BIRS workshop: Entropic Regulariz
 ation of Optimal Transport and Applications\n\n\nAbstract\nWe discuss a si
 mple but potent modification of the Sinkhorn algorithm based on overrelaxa
 tion. We provide an a priori estimate for the crucial overrelaxation param
 eter which guarantees both global and improved local convergence.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Flavien Léger (Sciences Po Paris)
DTSTART:20210625T155000Z
DTEND:20210625T163000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/20
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/20/">Taylor expansions for the regularized optimal transport probl
 em</a>\nby Flavien Léger (Sciences Po Paris) as part of BIRS workshop: En
 tropic Regularization of Optimal Transport and Applications\n\n\nAbstract\
 nWe prove Taylor expansions of the regularized optimal transport problem w
 ith general cost as the temperature goes to zero. \nOur first contribution
  is a multivariate Laplace expansion formula. We show that the first-order
  terms involve the scalar curvature in the corresponding Hessian geometry.
  \nWe then obtain: \n - first-order expansion of the potentials\; \n - sec
 ond-order expansion of the optimal transport value. \nJoint work with Pier
 re Roussillon\, François-Xavier Vialard and Gabriel Peyré.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yunan Yang (New York University)
DTSTART:20210625T164000Z
DTEND:20210625T172000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/21
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/21/">Optimal transport-based objective function for physical inver
 se problems</a>\nby Yunan Yang (New York University) as part of BIRS works
 hop: Entropic Regularization of Optimal Transport and Applications\n\n\nAb
 stract\nWe have proposed the quadratic Wasserstein distance from optimal t
 ransport theory for inverse problems\, including nonlinear medium reconstr
 uction for waveform inversions and chaotic dynamical systems parameter ide
 ntification. Traditional methods for both applications suffered from longs
 tanding difficulties such as nonconvexity and noise sensitivity. As we adv
 ance\, we discover that the advantages of using optimal transposed-based m
 etrics apply in a broader class of data-fitting problems where the continu
 ous dependence between the parameter and the data involves the change of d
 ata phase or support of the data. The implicit regularization effects of t
 he Wasserstein distance similar to a weak norm also help improve stability
  of parameter identification.\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Katy Craig (University of California Santa Barbara)
DTSTART:20210625T173000Z
DTEND:20210625T181000Z
DTSTAMP:20260404T042017Z
UID:BIRS-21w5120/22
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/BIRS-
 21w5120/22/">A blob method for diffusion and applications to sampling and 
 two layer neural networks</a>\nby Katy Craig (University of California San
 ta Barbara) as part of BIRS workshop: Entropic Regularization of Optimal T
 ransport and Applications\n\n\nAbstract\nGiven a desired target distributi
 on and an initial guess of that distribution\, composed of finitely many s
 amples\, what is the best way to evolve the locations of the samples so th
 at they more accurately represent the desired distribution? A classical so
 lution to this problem is to allow the samples to evolve according to Lang
 evin dynamics\, the stochastic particle method corresponding to the Fokker
 -Planck equation. In today’s talk\, I will contrast this classical appro
 ach with a deterministic particle method corresponding to the porous mediu
 m equation. This method corresponds exactly to the mean-field dynamics of 
 training a two layer neural network for a radial basis function activation
  function. We prove that\, as the number of samples increases and the vari
 ance of the radial basis function goes to zero\, the particle method conve
 rges to a bounded entropy solution of the porous medium equation. As a con
 sequence\, we obtain both a novel method for sampling probability distribu
 tions as well as insight into the training dynamics of two layer neural ne
 tworks in the mean field regime. This is joint work with Karthik Elamvazhu
 thi (UCLA)\, Matt Haberland (Cal Poly)\, and Olga Turanova (Michigan State
 ).\n
LOCATION:https://stable.researchseminars.org/talk/BIRS-21w5120/22/
END:VEVENT
END:VCALENDAR
