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:20251102T060000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:69f5682cb4781 DTSTART;TZID=America/Toronto:20260505T093000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260505T123000 URL:https://uwaterloo.ca/pure-mathematics/events/phd-defence-2 SUMMARY:PhD Defence CLASS:PUBLIC DESCRIPTION:JENNIFER ZHU\, UNIVERSITY OF WATERLOO\n\n_Categorical Limits o f Quantum Graphs and Possibilities Induced by\nQuantumPseudometrics_\n\nQu antum graphs and quantum pseudometrics as defined by Kuperberg and\nWeaver have roots in quantum errorcorrection but have since been\ndeveloped as s ubjects in their own right. The motivation for the first\nhalf of thisthes is is to build an infinite quantum graph from finite\nquantum graphs. The latter have been subjected to fargreater scrutiny\ndue to their connection s to categorical quantum theory\, while the\nformer have been somewhatnegl ected. To be precise\, we define and take\nthe categorical (co)limit of qu antum graphs by developing a newnotion\nof morphism compatible with previo us notions but carrying less\nbaggage. The inspiration for the secondhalf follows from the\n(unpublished) theorem that pure states on a von Neumann algebra\n\\mathcal{M} are givenby maximal filters in the projection lattic e of\n\\mathcal{M}. Upon the observation that points in a metric space$(X\ ,\nd)$ with topology $\\tau$ are also given by maximal filters $\\tau$ and \nthat quantum pseudometrics provide anotion of distance between\nprojecti ons in $B(\\ell^2) \\overline{\\otimes} \\mathcal M$\, we are led\nto a no tion ofdistance $f$ between pure states induced by these\nquantum pseudome trics. Also this function $f$ does not satisfythe\ntriangle inequality\, w e make some parallels between it and David\nLewis's conception of ``possib le worlds.''\n\nMC 2009 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cb72e2 DTSTART;TZID=America/Toronto:20260505T150000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260505T160000 URL:https://uwaterloo.ca/pure-mathematics/events/analysis-seminar-217 SUMMARY:Analysis Seminar CLASS:PUBLIC DESCRIPTION:PAUL SKOUFRANISYORK UNIVERSITY\n\n_Non-Commutative Majorization _\n\nThe maps that send a self-adjoint matrix $A$ to $U^*AU$ where $U$ is a\nunitary matrix are essential inQuantum Information Theory as these\nmap s transmit quantum information in a reversible way. When\nconvexcombinatio ns of such maps are taken\, one obtains what are known\nas the mixed unita ry quantum channels\, whichare essential models for\nhow quantum informati on can be transmitted when noise is present. Just\nas the unitaryconjugate s of a self-adjoint matrix can be determined\nvia spectral data\, so too c an the image of a self-adjointmatrix under\nall possible mixed unitary qua ntum channels. Since this is equivalent\nto characterizing the convexhull of the unitary orbit of a\nself-adjoint matrix\, this problem has a well-k nown solution from\noperator theoryinvolving the notion of matrix majoriza tion of one\nself-adjoint operator by another. In this talk\, we will exam inehow we\ncan extend the notion of matrix majorization to non-commutative \ncontexts. In particular\, we will discussa notion of non-commutative\nma jorization that characterizes the potential outputs under all\nquantum cha nnels ofany non-commutative tuple of matrices. This is\nbased on joint wor k with Matt Kennedy.\n\nMC 5417 or Join on Zoom\n[https://uwaterloo.zoom.u s/j/94186354814?pwd=NGpLM3B4eWNZckd1aTROcmRreW96QT09] DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cb7cc0 DTSTART;TZID=America/Toronto:20260501T110000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260501T120000 URL:https://uwaterloo.ca/pure-mathematics/events/algebraic-geometry-seminar -14 SUMMARY:Algebraic Geometry Seminar CLASS:PUBLIC DESCRIPTION:CATHERINE ST-PIERRE\, UNIVERSITY OF WATERLOO\n\n_Organizational meeting_\n\nWe will organize the seminars for the summer.\n\nMC 5403 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cb8613 DTSTART;TZID=America/Toronto:20260429T120000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260429T130000 URL:https://uwaterloo.ca/pure-mathematics/events/analysis-seminar-216 SUMMARY:Analysis Seminar CLASS:PUBLIC DESCRIPTION:JENNIFER ZHU\, UNIVERSITY OF WATERLOO\n\n_Morphisms of Quantum Confusability Graphs_\n\nIt would be unrealistic to have an information ch annel — quantum or\nclassical — that always sends information with abs olute accuracy\;\nthat is\, we must expect a channel to have noise. In 195 6\, Shannon\nintroduced the notion of zero-error capacity of a noisy (clas sical)\nchannel using the confusability graph of this channel. In 2010\, D uan\,\nSeverini\, and Winter developed the analogous notion (quantum\nconf usability graphs) for quantum channels and show that one can\nrecover vari ous types of zero-error capacities of quantum channels. In\nthe first half of this talk\, we will see how these quantum\nconfusability graphs are de rived and how they subsume Shannon's notion\nof classical confusability gr aphs.\n\nQNC 1201 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cb9078 DTSTART;TZID=America/Toronto:20260430T140000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260430T153000 URL:https://uwaterloo.ca/pure-mathematics/events/differential-geometry-work ing-seminar-186 SUMMARY:Differential Geometry Working Seminar CLASS:PUBLIC DESCRIPTION:FACUNDO CAMANO\, UNIVERSITY OF WATERLOO\n\n_Boundary Conditions for Non-Euclidean Monopoles_\n\nIn this talk\, I will discuss the heurist ic behind defining asymptotics\nfor monopoles. Specifically\, the asymptot icsshould be abelian\nsolutions embedded into the gauge group. I will firs t go over this\nheuristic for Euclideanmonopoles and then move on to non-E uclidean\nsituations such as hyperbolic and singly periodic.\n\nMC 5403 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cb9ba7 DTSTART;TZID=America/Toronto:20260423T143000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260423T160000 URL:https://uwaterloo.ca/pure-mathematics/events/differential-geometry-work ing-seminar-185 SUMMARY:Differential Geometry Working Seminar CLASS:PUBLIC DESCRIPTION:PAUL CUSSON\, UNIVERSITY OF WATERLOO\n\n_Monopoles with rotatio nal symmetry_\n\nWe will first look at SU(2)-monopoles invariant under the action of a\ncircle subgroup of SO(3) about the z-axis.The polynomials cu tting out\ntheir spectral curves in TP^1 will be derived\, and these will be used\nto describe thespectral curves of S^1-invariant SU(N)-monopoles f or\narbitrary N.\n\nMC 5403 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cba610 DTSTART;TZID=America/Toronto:20260420T130000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260420T143000 URL:https://uwaterloo.ca/pure-mathematics/events/computability-learning-sem inar-169 SUMMARY:Computability Learning Seminar CLASS:PUBLIC DESCRIPTION:ELAN ROTH & WILLIAM DAN\, UNIVERSITY OF WATERLOO\n\n_Randomness in the Arithmetic Hierarchy_\n\nWe will introduce a problem posed by Bien venu\, Csima\, and\nHarrison-Trainor about transforming indices of random left c.e. reals\nto optimal machines with specific halting probabilities. Then\, we will\nprove two results that have been useful in our attempts to resolve the\nopen problem.\n\nMC 5403 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cbaf81 DTSTART;TZID=America/Toronto:20260416T143000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260416T160000 URL:https://uwaterloo.ca/pure-mathematics/events/differential-geometry-work ing-seminar-184 SUMMARY:Differential Geometry Working Seminar CLASS:PUBLIC DESCRIPTION:ALEX PAWELKO\, UNIVERSITY OF WATERLOO\n\n_Morse Theory via Har monic Oscillators_\n\nWe will discuss the approach to Morse Theory origina lly due to Witten\,\nwhere one constructs deformed Laplaceoperators whose low-energy\neigenvectors concentrate near the critical points of one's Mor se\nfunction\, and thenuses Hodge theory to relate this to de Rham\ncohomo logy.\n\nMC 5403 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cbb845 DTSTART;TZID=America/Toronto:20260407T100000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260407T110000 URL:https://uwaterloo.ca/pure-mathematics/events/number-theory-seminar-165 SUMMARY:Number Theory Seminar CLASS:PUBLIC DESCRIPTION:ILA VARMA\, UNIVERSITY OF TORONTO\n\n_Counting Number Fields by P^1 height_\n\nWhen do two irreducible polynomials with integer coefficie nts define\nthe same number field? One can define an action of GL_2 × GL_ 1 on the\nspace of polynomials of degree n so that for any two polynomials f and\ng in the same orbit\, the roots of f may be expressed as rational\ nlinear transformations of the roots of g\; thus\, they generate the same\ nfield. In this article\, we show that almost all polynomials of degree\nn with size at most X can only define the same number field as another\npol ynomial of degree n with size at most X if they lie in the same\norbit for this group action. (Here we measure the size of polynomials\nby the great est absolute value of their coefficients.)\n\nThis improves on work of Bha rgava\, Shankar\, and Wang\, who proved a\nsimilar statement for a positiv e proportion of polynomials. Using this\nresult\, we prove that the number of degree n fields such that the\nsmallest polynomial defining the field has size at most X is\nasymptotic to a constant times X^{n+1} as long as n \\ge 3. For n = 2\,\nwe obtain a precise asymptotic of the form 27/(pi^2) * X^2\n\nThis is joint work with Arango-Pineros\, Gundlach\, Lemke Olive r\,\nMcGown\, Sawin\, Serrano Lopez\, and Shankar.\n\nMC 5479 DTSTAMP:20260502T025748Z END:VEVENT BEGIN:VEVENT UID:69f5682cbc198 DTSTART;TZID=America/Toronto:20260413T143000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20260413T153000 URL:https://uwaterloo.ca/pure-mathematics/events/pure-math-colloquium-66 SUMMARY:Pure Math Colloquium CLASS:PUBLIC DESCRIPTION:HENRIQUE SÀ EARP\, UNICAMP\n\n_Updates on flows of geometric s tructures_\n\nAiming at a public with interests among Riemannian and compl ex\ngeometry\, Lie groups and parabolic PDEs\, Iwill recall some results\n towards a general analytical theory for flows of H-structures\,\nobtained with Fadel\,Loubeau and Moreno. Then\, as a concrete example\, I\nwill pre sent some recent progress on SU(2)-flows on 4-manifolds\,\ninitiating a cl assification programme of ‘parabolic’ flows\, based\non a representati on-theoretic methodoriginally due to Bryant in the\ncontext of G2 geometry \, obtained with Fowdar.\n\nMC 5501 DTSTAMP:20260502T025748Z END:VEVENT END:VCALENDAR