BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Stefaan Vaes (KU Leuven) DTSTART:20220211T163000Z DTEND:20220211T173000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/1 DESCRIPTION:Title: Classification questions in operator algebras and ergodic theory\nb y Stefaan Vaes (KU Leuven) as part of University of Regina pims distinguis hed lectures\n\n\nAbstract\nThe theme of this lecture is the dichotomy bet ween amenability and non-amenability\, both in operator algebras and ergod ic theory. I will review the fundamental classification results for amenab le von Neumann algebras due to Connes and Haagerup. Then I will focus on t he nonamenable case\, where Popa's deformation/rigidity theory has led to striking rigidity theorems for von Neumann algebras associated with groups and actions of groups on measure spaces. I will survey some recent result s\, including the computation of invariants of II$_1$ factors and the chal lenging problem of deciding when II$_1$ factors can be embedded one into t he other.\n\nFollow the link to register in advance.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Tatjana Miljkovic (Miami University) DTSTART:20221014T213000Z DTEND:20221014T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/2 DESCRIPTION:Title: An overview of the recent loss modeling approaches and their impact on risk measures\nby Tatjana Miljkovic (Miami University) as part of Univ ersity of Regina pims distinguished lectures\n\n\nAbstract\nThe “key ris k measures” such as Value-at-Risk (VaR) and Conditional Tail Expectation (CTE) are important for capital allocation decisions as they inform actua ries and risk managers about the degree to which a line of business or a c ompany is exposed to a particular aspect of risk. These measures are typic ally estimated based on the best-fitting statistical model selected from a set of models considered in loss modeling.\n\nIn this talk\, three differ ent approaches for finding the best fitting model will be introduced using computational tools. The first approach is based on finite mixtures where the components belong to the same parametric distribution family. The sec ond approach uses composite models where two different distributions are u sed for the head and tail and these distributions are combined in a smooth way at a specific threshold. Finally\, the model averaging approach will be introduced and applied to the estimation of risk measures. The results of the simulation studies will be discussed as well as the applications us ing two popular data sets on Danish Fire and Norwegian Fire losses.\n\nPle ase register in advance to receive the Zoom link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Alexander Kupers (University of Toronto) DTSTART:20221028T213000Z DTEND:20221028T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/3 DESCRIPTION:Title: Diffeomorphisms of discs\nby Alexander Kupers (University of Toront o) as part of University of Regina pims distinguished lectures\n\nLecture held in RIC 208.\n\nAbstract\nDiscs are among the simplest manifolds\, but their groups of diffeomorphisms can be very complicated. I will describe the techniques from geometry topology and dynamics that were used to under stand these groups in low dimensions\, the relationship of these groups to stable homotopy theory and number theory in high dimensions\, and recent breakthroughs in understanding their rational homotopy type. This talk wil l be aimed at a broad audience.\n\nThe talk will be held in person and liv estreamed on Zoom. Register in advance to receive the Zoom link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Emily Riehl (Johns Hopkins University) DTSTART:20230210T213000Z DTEND:20230210T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/4 DESCRIPTION:Title: A reintroduction to proofs\nby Emily Riehl (Johns Hopkins Universit y) as part of University of Regina pims distinguished lectures\n\n\nAbstra ct\nIn an introduction to proofs course\, students learn to write proofs i nformally in the language of set theory and classical logic. In this talk\ , I'll explore the alternate possibility of teaching students to write pro ofs informally in the language of dependent type theory. I'll argue that t he intuitions suggested by this formal system are closer to the intuitions mathematicians have about their praxis. Furthermore\, dependent type theo ry is the formal system used by many computer proof assistants both "under the hood" to verify the correctness of proofs and in the vernacular langu age with which they interact with the user. Thus\, students could practice writing proofs in this formal system by interacting with computer proof a ssistants such as Coq and Lean.\n\nRegister in advance to receive the Zoom link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Jiguo Cao (Simon Fraser University) DTSTART:20230915T213000Z DTEND:20230915T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/5 DESCRIPTION:Title: Machine Learning for Functional Data\nby Jiguo Cao (Simon Fraser Un iversity) as part of University of Regina pims distinguished lectures\n\n\ nAbstract\nFunctional data analysis (FDA) is a growing statistical field f or analyzing curves\, images\, or any multidimensional functions\, in whic h each random function is treated as a sample element. Functional data is found commonly in many applications such as longitudinal studies and brain imaging. In this talk\, I will present a methodology for integrating func tional data into deep neural networks. The model is defined for scalar res ponses with multiple functional and scalar covariates. A by-product of the method is a set of dynamic functional weights that can be visualized duri ng the optimization process. This visualization leads to greater interpret ability of the relationship between the covariates and the response relati ve to conventional neural networks. The model is shown to perform well in a number of contexts including prediction of new data and recovery of the true underlying relationship between the functional covariate and scalar r esponse\; these results were confirmed through real data applications and simulation studies.\n\nPlease register in advance at the provided link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Jacob Tsimerman (University of Toronto) DTSTART:20230922T213000Z DTEND:20230922T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/6 DESCRIPTION:Title: Transcendence of period integrals over function fields\nby Jacob Ts imerman (University of Toronto) as part of University of Regina pims disti nguished lectures\n\n\nAbstract\nPeriods are integrals of differential for ms\, and their study spans many branches of mathematics\, including diopha ntine geometry\, differential algebra\, and algebraic geometry. If one res tricts their attention to periods arising over $\\mathbb{Q}$\, then the Gr othendieck Period Conjecture is a precise way of saying that these are as transcendental as is allowed by the underlying geometry. While this is a r emarkably general statement (and very open)\, it does not include another major (also open!) conjecture in transcendence theory - the Schanuel conje cture. In particular\, $e$ is not a period\, even though it can be describ ed through periods via the relation that the integral from 1 to $e$ of $dx /x$ is 1. We shall present a generalization due to André which unifies th e two conjectures in a satisfactory manner.\n\nIn the (complex) function f ield case\, a lot more is known. The Grothendieck Period Conjecture has be en formulated and proved by Ayoub and Nori. We shall explain the geometric analogue of the André - Grothendieck Period Conjecture and present its p roof. It turns out that this conjecture is (almost) equivalent to a functi onal-transcendence statement of extreme generality known as the Ax-Schanue l conjecture\, which has been the subject of a lot of study over the past decade in connection with unlikely intersection problems. The version rele vant to us is a comparison between the algebraic and flat coordinates of g eometric local systems. We will explain the ideas behind the proofs of thi s Ax-Schanuel conjecture and explain how it implies the relevant period co njecture.\n\nRegister in advance to receive the Zoom link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Ben Williams (University of British Columbia) DTSTART:20231020T213000Z DTEND:20231020T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/7 DESCRIPTION:Title: Topology and Azumaya algebras\nby Ben Williams (University of Briti sh Columbia) as part of University of Regina pims distinguished lectures\n \nLecture held in RIC 209.\n\nAbstract\nAn Azumaya algebra is something th at is "locally" isomorphic to a matrix algebra. By varying the sense of "l ocally"\, we arrive at different incarnations of the concept. The motivati ng example is that of central simple algebras over a field. In this talk\, I will concentrate on the topological aspects of the idea. I will give ex amples and show that the flexibility of topology allows one to produce cou nterexamples in algebra. At the end\, I will mention some problems I do no t know how to solve.\n\nRegister in advance for the Zoom link.\n\nThis eve nt is supported by PIMS.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Teena Gerhardt (Michigan State University) DTSTART:20240308T213000Z DTEND:20240308T223000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/8 DESCRIPTION:Title: Interactions between topology and algebra: advances in algebraic K-theo ry\nby Teena Gerhardt (Michigan State University) as part of Universit y of Regina pims distinguished lectures\n\n\nAbstract\nThe field of algebr aic topology has exposed deep connections between topology and algebra. On e example of such a connection comes from algebraic K-theory. Algebraic K- theory is an invariant of rings\, defined using tools from topology\, that has important applications to algebraic geometry\, number theory\, and ge ometric topology. Algebraic K-groups are difficult to compute\, but advanc es in algebraic topology have led to many recent computations which were p reviously intractable. In this talk I will introduce algebraic K-theory an d its applications\, and discuss recent advances in this field.\n\nRegiste r in advance to receive the Zoom link.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/8/ END:VEVENT BEGIN:VEVENT SUMMARY:Octav Cornea (Université de Montréal) DTSTART:20250417T203000Z DTEND:20250417T213000Z DTSTAMP:20260422T215001Z UID:ReginaPIMS/9 DESCRIPTION:Title: Complexity of Lagrangian submanifolds\nby Octav Cornea (Université de Montréal) as part of University of Regina pims distinguished lectures \n\n\nAbstract\nLagrangian submanifolds are a central object of study in s ymplectic topology. Their rigidity properties have been uncovered via Floe r theory since the early ’90’s. The talk will briefly review the subje ct\, in particular how triangulated category structures naturally arise in this context through work of Donaldson\, Kontsevich\, Fukaya\, and others . Further\, will be discussed the more recent\, natural role of persistenc e theory\, in the sense common in data science. Finally\, we will outline how complexity measurements based on persistence methods reflect topologic al and dynamical invariants\, such as topological entropy.\n\nRegister in advance to receive the Zoom link.\n\nThis event is supported by PIMS.\n LOCATION:https://researchseminars.org/talk/ReginaPIMS/9/ END:VEVENT END:VCALENDAR