BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Drupal iCal API//EN X-WR-CALNAME:Events items teaser X-WR-TIMEZONE:America/Toronto BEGIN:VTIMEZONE TZID:America/Toronto X-LIC-LOCATION:America/Toronto BEGIN:DAYLIGHT TZNAME:EDT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 DTSTART:20260308T070000 END:DAYLIGHT BEGIN:STANDARD TZNAME:EST TZOFFSETFROM:-0400 TZOFFSETTO:-0500 DTSTART:20261101T060000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:6acb30258a65f DTSTART;TZID=America/Toronto:20261112T153000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261112T163000 URL:https://uwaterloo.ca/pure-mathematics/events/geometry-and-topology-semi nar-ergun-yalcin-free-actions SUMMARY:Geometry and Topology Seminar | Ergun Yalcin | Free Actions on\nPro ducts of Real Projective Spaces CLASS:PUBLIC DESCRIPTION:ERGUN YALCIN (BILKENT UNIVERSITY AND UNIVERSITY OF WATERLOO) \n \n_Free Actions on Products of Real Projective Spaces_ \nThere are many co njectures on restrictions on finite groups that can\nact freely on a topol ogical space with prescribed homotopy type. The\nmost famous of these conj ectures is the rank conjecture\, which claims\nthat if an elementary abeli an p-group of rank r acts freely on a\nproduct of k spheres\, then r is le ss than or equal to k. In 1983\,\nCusick made a similar conjecture for fre e actions on products of real\nprojective spaces. We recently solved the h omotopy-theoretic version\nof Cusick’s conjecture. I will explain some o f the main ideas used\nin the proof of this conjecture\, after introducing the necessary\nbackground. \nMC 5417 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb30258dd56 DTSTART;TZID=America/Toronto:20261020T100000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261020T110000 URL:https://uwaterloo.ca/pure-mathematics/events/number-theory-seminar-xing chi-ruan-hilbert-kamke-problem SUMMARY:Number Theory Seminar | Xingchi Ruan | The Hilbert-Kamke Problem in \nNumber Fields CLASS:PUBLIC DESCRIPTION:XINGCHI RUAN (UNIVERSITY OF WATERLOO) \n\n_The Hilbert-Kamke Pr oblem in Number Fields_ \nThe Hilbert-Kamke problem is a generalization of Waring’s problem to\na system of equations\, in which the sums of the f irst n powers of the\nsame variables are given. By the circle method\, the existence of\nsolutions depends on a positive lower bound for the singula r series.\nIn this talk\, we study this problem over a number field. We se t up the\ncircle method\, following Siegel and Wang\, and write the singul ar\nseries as a product of local densities. Under a necessary arithmetic\n condition\, and with enough variables\, we prove that the singular\nseries is bounded below by a positive constant depending only on the\nnumber of equations and the degree of the field. The proof is given\nfirst for quadr atic fields and then for every number field. \nMC 5501 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb30258e950 DTSTART;TZID=America/Toronto:20261008T133000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261008T150000 URL:https://uwaterloo.ca/pure-mathematics/events/computability-learning-sem inar-noah-nazareth-jump-structure-0 SUMMARY:Computability Learning Seminar | Noah Nazareth | The jump of a\nstr ucture II CLASS:PUBLIC DESCRIPTION:NOAH NAZARETH (UNIVERSITY OF WATERLOO) \n\n_The jump of a struc ture II_ \nWe will begin with a proof of the Ash-Knight-Manasse-Slaman and \nChisholm theorem. We will then discuss some properties of effective\nbi- interpretability\, and start the proof of the first jump inversion\ntheore m for structures. If time permits\, we will also show several\nconsequence s of the theorem. \nMC 5403 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb30258f592 DTSTART;TZID=America/Toronto:20261009T093000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261009T110000 URL:https://uwaterloo.ca/pure-mathematics/events/algebraic-geometry-working -seminar-francisco-villacis-linear SUMMARY:Algebraic Geometry Working Seminar | Francisco Villacis | Linear\nA moebas and their Combinatorial Properties CLASS:PUBLIC DESCRIPTION:FRANCISCO VILLACIS (UNIVERSITY OF WATERLOO) \n\n_Linear Amoebas and their Combinatorial Properties_ \nA projective toric variety \\(X\\Si gma\\) comes with a moment map\n\\(\\mu\\)\, whose image is a convex polyt ope that encodes a lot of the\ngeometry of \\(X\\Sigma\\). These moment ma ps and their associated\npolytopes have played a fundamental role in quant ization programs and\nmirror symmetry. One natural question when studying these maps is\nwhether the image \\(\\mu(X)\\) also encodes geometric info rmation of a\nsubvariety \\(X\\subset X_\\Sigma\\). In this talk\, we intr oduce\ncombinatorial objects that let us study this image\, called the\n(c ompactified) amoeba of \\(X\\)\, in the case where \\(X\\) is a linear\nsu bspace of projective space. \nMC 5403 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb3025901b8 DTSTART;TZID=America/Toronto:20261006T143000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261006T160000 URL:https://uwaterloo.ca/pure-mathematics/events/differential-geometry-work ing-seminar-facundo-camano-su2 SUMMARY:Differential Geometry Working Seminar | Facundo Camano | SU(2) is\n lying to us CLASS:PUBLIC DESCRIPTION:FACUNDO CAMANO (UNIVERSITY OF WATERLOO) \n\n_SU(2) is lying to us._ \nWe will compute the index of the deformation operator of a BPS\nmon opole on R^3. During this computation\, we will encounter how\nclassical i ndex results fall short in the presence of symmetry\nbreaking. A hybridiza tion of the b-calculus and scattering calculus\nwill be the remedy to bypa ss the symmetry breaking and perform the\ncomputation. \nMC 5417 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb302590d7e DTSTART;TZID=America/Toronto:20261007T140000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261007T150000 URL:https://uwaterloo.ca/pure-mathematics/events/logic-analysis-working-sem inar-jashan-bal-more-aw-algebras SUMMARY:Logic in Analysis Working Seminar | Jashan Bal | More on AW*-algebr as CLASS:PUBLIC DESCRIPTION:JASHAN BAL (UNIVERSITY OF WATERLOO) \n\n_More on AW*-algebras_ \nWe will continue working through Arulseelan and Hanson's recent paper\no n AW*-algebras. \nMC 5301 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb3025918ba DTSTART;TZID=America/Toronto:20261006T160000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261006T172000 URL:https://uwaterloo.ca/pure-mathematics/events/analysis-seminar-david-jek el-optimal-transport-free-and SUMMARY:Analysis Seminar | David Jekel | Optimal transport in the free and\ nquantum settings CLASS:PUBLIC DESCRIPTION:DAVID JEKEL (UNIVERSITY OF OTTAWA) \n\n_Optimal transport in th e free and quantum settings_ \nWe discuss several noncommutative generaliz ations of the classical\nWasserstein distance of two probability measures on R^d\, or more\ngeneral metric spaces\, which measures the minimal L^2 d istance of two\nrandom variables with the given distributions. The first m otivation\ncomes from free probability theory\, where ideas from optimal t ransport\ntheory have been used to show isomorphism of von Neumann algebra s and\nappear in functional inequalities with free entropy\, as well as\np roviding a general notion of \"perturbing generators\" of a von Neumann\na lgebra. The second motivation comes from quantum information theory\,\nwhe re optimal transport theory provides a way to assign distances for\nstates on a von Neumann algebra. As we will see\, Duvenhage's version\nof quadra tic Wasserstein distance relates quite closely to the Biane\nand Voiculesc u's free Wasserstein distance. We discuss these distances\nin a common fra mework and demonstrate several properties that make the\nnoncommutative se tting more challenging\, including non-separability of\nthe Wasserstein sp ace\, and a stark difference between the Wasserstein\nand weak-* topologie s on certain state spaces. \nMC 5403 \nZoom Link\n[https://uwaterloo.zoom. us/j/94186354814?pwd=NGpLM3B4eWNZckd1aTROcmRreW96QT09] DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb302592486 DTSTART;TZID=America/Toronto:20261008T130000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261008T140000 URL:https://uwaterloo.ca/pure-mathematics/events/student-number-theory-semi nar-julius-frizzell-organizational SUMMARY:Student Number Theory Seminar | Julius Frizzell | Organizational\nM eeting CLASS:PUBLIC DESCRIPTION:JULIUS FRIZZELL (UNIVERSITY OF WATERLOO)\n\n_Organizational Mee ting_ \nWe will decide the order of speakers for the term \nMC 5479 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb302592fbd DTSTART;TZID=America/Toronto:20261008T150000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261008T160000 URL:https://uwaterloo.ca/pure-mathematics/events/logicmodel-theory-seminar- daniel-max-hoffmann-amenable-tame SUMMARY:Logic/Model Theory Seminar | Daniel Max Hoffmann | Amenable tame\nf lows: Theorems motivated by model-theoretic dynamics CLASS:PUBLIC DESCRIPTION:DANIEL MAX HOFFMANN (UNIVERSITY OF WARSAW) \n_Amenable tame flo ws: Theorems motivated by model-theoretic dynamics_ \n\nThere is an intere sting interplay between model theory and topological\ndynamics. Newelski s uggested using the machinery of topological\ndynamics to study definable g roups and the related dynamics on spaces\nof types. For example\, he propo sed a conjecture stating that\, under\nsuitable model-theoretic assumption s\, the Ellis group of a flow should\nbe isomorphic to the compact group ( G/G^{00}). This conjecture was\nconfirmed for definably amenable groups in NIP by Chernikov and Simon\n(2018)\, but was also refuted in NIP for SL(2 \,R) by Gismatullin\,\nPenazzi and Pillay (2015). Krupiński and Pillay fo rmulated a weaker\nversion\, the so-called revised Newelski conjecture\, s tating that\,\nunder NIP\, the Ellis group associated with definable group dynamics\nhas a Hausdorff (\\tau)-topology. This revised conjecture was c onfirmed\nby Chernikov\, Gannon and Krupiński for definable group dynamic s in a\nmetrizable setting. Basso and Zucker then extended this result to the\nnon-metrizable setting via forcing\; in fact\, they generalized some\ nparts of Glasner’s structural results. \nKrupiński and I observed that an abstract variant of Newelski’s\noriginal conjecture follows from Gla sner’s results for amenable\,\ntame\, minimal and metrizable flows. Our goal was then to remove the\nmetrizability assumption\, as had been done i n the case of the revised\nconjecture. This led to results on the amenabil ity of the Ellis\nsemigroup and on the measurable structure of amenable mi nimal tame\nflows. These results will be presented in two papers. \nThe fi rst is already available on arXiv:\nhttps://arxiv.org/abs/2607.24381. \nMC 5403 DTSTAMP:20261011T064349Z END:VEVENT BEGIN:VEVENT UID:6acb302593b41 DTSTART;TZID=America/Toronto:20261002T170000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20261002T180000 URL:https://uwaterloo.ca/pure-mathematics/events/grad-student-colloquium-ow en-sharpe-primality-testing-easy SUMMARY:Grad Student Colloquium | Owen Sharpe | Primality Testing Is Easy b ut\nFactoring Is Hard CLASS:PUBLIC DESCRIPTION:OWEN SHARPE (UNIVERSITY OF WATERLOO)\n\n_Primality Testing Is E asy but Factoring Is Hard_ \nYou've probably heard of RSA\, and that it re lies on factoring being a\nhard problem\, but did you ever wonder where th e large primes come from\nin the first place? We will take a tour through primality testing and\nfactoring algorithms\, starting with trial factorin g and the sieve of\nEratosthenes\, through probabilistic methods like the Miller-Rabin\nprobabilistic test and the Pollard rho method\, to the bleed ing edge of\nAKS and the quadratic sieve. \nMC 5417 DTSTAMP:20261011T064349Z END:VEVENT END:VCALENDAR