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X-WR-CALDESC:Events for Claremont Center for the Mathematical Sciences
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DTSTART;TZID=America/Los_Angeles:20251201T161500
DTEND;TZID=America/Los_Angeles:20251201T171500
DTSTAMP:20260403T163719
CREATED:20251126T233248Z
LAST-MODIFIED:20251126T233248Z
UID:3935-1764605700-1764609300@colleges.claremont.edu
SUMMARY:Structure-Aware Adaptive Nonconvex Optimization for Deep Learning and Scientific Computing (Minxin Zhang\, UCLA)
DESCRIPTION:Abstract: Modern machine learning and scientific computing pose optimization challenges of unprecedented scale and complexity\, demanding fundamental advances in both theory and algorithmic design for nonconvex optimization. This talk presents recent advances that address these challenges by exploiting matrix and tensor structures\, integrating adaptivity\, and leveraging sampling techniques. In the first part\, I introduce AdaGO\, a new optimizer that combines orthogonalized momentum updates with adaptive learning rates. Building on the recent success of the Muon optimizer in large language model training\, AdaGO incorporates an AdaGrad-type stepsize that scales orthogonalized update directions by accumulated past gradient norms. This design preserves the structural advantage of orthogonalized updates while adapting stepsizes to noise and the optimization landscape. We establish optimal convergence rates for smooth nonconvex functions and demonstrate improved performance over Muon and Adam on classification and regression tasks. The second part focuses on zeroth-order global optimization. We develop a theoretical framework for inexact proximal point (IPP) methods for global optimization\, establishing convergence guarantees when proximal operators are estimated either deterministically or stochastically. The quadratic regularization in the proximal operator induces a concentrated Gibbs measure landscape that facilitates effective sampling. We propose two sampling-based algorithms: TT-IPP\, which constructs a low-rank tensor-train (TT) approximation using a randomized TT-cross algorithm\, and MC-IPP\, which employs Monte Carlo integration. Both IPP algorithms adaptively balance efficiency and accuracy in proximal operator estimation\, achieving strong performance across diverse benchmark functions and applications. Together\, these works advance structure-aware adaptive first-order optimization for deep learning and zeroth-order global optimization in scientific computing.
URL:https://colleges.claremont.edu/ccms/event/structure-aware-adaptive-nonconvex-optimization-for-deep-learning-and-scientific-computing-minxin-zhang-ucla/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20251202T121500
DTEND;TZID=America/Los_Angeles:20251202T131000
DTSTAMP:20260403T163719
CREATED:20250808T202734Z
LAST-MODIFIED:20251120T202437Z
UID:3778-1764677700-1764681000@colleges.claremont.edu
SUMMARY:Positivity aspects of complete homogeneous symmetric polynomials (Stephan Garcia\, Pomona)
DESCRIPTION:Hunter’s theorem ensures that the complete homogeneous symmetric (CHS) polynomials of even degree are positive definite functions.  We provide new proofs of Hunter’s theorem\, applications to operator theory\, and a noncommutative (NC) generalization that sheds light even on the commutative case.  Surprisingly\, this work emerged from a problem in analytic combinatorics.
URL:https://colleges.claremont.edu/ccms/event/antc-talk-stephan-garcia-pomona-2/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20251202T160000
DTEND;TZID=America/Los_Angeles:20251202T170000
DTSTAMP:20260403T163719
CREATED:20250917T202344Z
LAST-MODIFIED:20251112T013717Z
UID:3845-1764691200-1764694800@colleges.claremont.edu
SUMMARY:Claremont Topology Seminar: Indraneel Tambe (UCLA)
DESCRIPTION:We welcome all undergraduate/graduate students and faculty to attend topology seminar! \nSpeaker: Indraneel Tambe (UCLA) \nTitle: Steinberg skein relations at roots of unity \nAbstract: This talk discusses some of the relationships between skein theory and the representation theory of quantum sl2 when q is a root of unity. Specifically\, I focus on the Frobenius pullback functor on Uq sl2 representations and see how this relates to Bonahon-Wong’s Frobenius skein homomorphism between Kauffman bracket skein modules. I’ll describe results from my joint work with Vijay Higgins in which we proved what we called Steinberg skein identities and used these in a new proof of the well-definition of the Frobenius skein homomorphism.
URL:https://colleges.claremont.edu/ccms/event/claremont-topology-seminar-ko-honda-ucla/
LOCATION:Fletcher 104\, Pitzer College\, 1050 N Mills Ave\, Claremont\, 91711\, United States
CATEGORIES:Topology Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20251205T110000
DTEND;TZID=America/Los_Angeles:20251205T121500
DTSTAMP:20260403T163719
CREATED:20250923T142446Z
LAST-MODIFIED:20251205T155429Z
UID:3868-1764932400-1764936900@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Konstantin Zuev (Caltech)
DESCRIPTION:CCMS Colloquium invites you to a talk by Konstantin Zuev (Caltech)\n\n \nTitle: Course-Prerequisite Networks\n \nAbstract: An academic curriculum is a complex system of courses and their interactions that lies at the heart of an academic institution and underlies its educational mission. Understanding these systems is essential for providing high-quality education. Course-prerequisite networks (CPNs) are directed acyclic graphs that model academic curricula by representing courses as nodes and prerequisite relationships between them as directed links. In this talk\, we will show how CPNs can be used to visualize\, analyze\, and optimize curricula; identify key courses; allocate teaching resources; quantify the strength of knowledge flow between departments; and uncover the most influential and interdisciplinary areas of study. The proposed methodology applies to any CPN and is illustrated using a network of courses taught at the California Institute of Technology. If time permits\, we will also discuss three new global CPN measures\, breadth\, depth\, and flux\, which enable macro-scale comparisons of different curricula. We illustrate these measures numerically using three real and synthetic CPNs from the Cyprus University of Technology\, the California Institute of Technology\, and Johns Hopkins University.\n \nBio: Dr. Konstantin Zuev is a Teaching Professor of Computing and Mathematical Sciences at the California Institute of Technology\, where he teaches a variety of courses in mathematics and statistics and conducts research on network science with undergraduate students. He is the author of about 30 papers and a forthcoming book\, Fundamentals of Statistical Inference: Foundations of Data Analysis. His teaching and research have been recognized with several awards: the ASCIT Teaching Award (2018 & 2023)\, the Carver Mead Seed Fund Grant (2023)\, the Graduate Student Council Teaching Award (2023)\, the Humboldt Research Fellowship for Experienced Researchers (2021)\, and the Northrop Grumman Prize for Excellence in Teaching (2019). For more information about his background\, please visit http://www.its.caltech.edu/~zuev/index.html
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-konstantin-zuev-caltech/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Bahar Acu":MAILTO:Bahar_Acu@pitzer.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20251206T100000
DTEND;TZID=America/Los_Angeles:20251206T115500
DTSTAMP:20260403T163719
CREATED:20251105T044832Z
LAST-MODIFIED:20251106T214405Z
UID:3919-1765015200-1765022100@colleges.claremont.edu
SUMMARY:GEMS December 6th Session
DESCRIPTION:This GEMS session will be facilitated by Professor Ryan Aschoff from the Claremont Graduate University.\n\n\nTitle: Randomness: Creating Order from Chaos\n\nAbstract: \nFrom the hiss of white noise to the gentle hum of ocean waves\, randomness surrounds us — yet hidden within that chaos lies remarkable order. In this talk\, we’ll explore how unpredictable events\, when viewed collectively\, give rise to smooth and universal patterns. We’ll listen to and visualize the “colors” of noise — white\, pink\, and brown — to see how sound encodes randomness across different frequencies. We’ll discover how unrelated random events\, like coin flips or marble drops\, merge into beautifully predictable bell-shaped distributions. And we’ll watch how diffusion and blurring transform disorder into structure\, revealing the same mathematics behind sound\, heat\, and motion.\n\nAlong the way\, we’ll take part in hands-on activities: generating and analyzing noise spectra\, building simple low-pass “smoothing” filters\, and experimenting with diffusion and random walks to watch chaos become order before our eyes. No advanced math required — just curiosity and a willingness to play with randomness!
URL:https://colleges.claremont.edu/ccms/event/gems-december-6th-session/
LOCATION:Shanahan B450\, Harvey Mudd College\, 301 Platt Blvd.\, Claremont\, 91711\, United States
CATEGORIES:GEMS
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260126T160000
DTEND;TZID=America/Los_Angeles:20260126T170000
DTSTAMP:20260403T163719
CREATED:20260121T185658Z
LAST-MODIFIED:20260121T185658Z
UID:3967-1769443200-1769446800@colleges.claremont.edu
SUMMARY:Fractional Brownian Motion: Small Increments and First Exit Time from One-sided Barrier (Qidi Peng\, CGU)
DESCRIPTION:Abstract: The talk introduces a conjecture on the first exit time of fractional Brownian motion: the upper-tail probability for a fractional Brownian motion to first exit a positive-valued barrier over time T has the exact asymptotic rate T^(H-1)\, where H is the Hurst parameter of the fractional Brownian motion. The talk tries to understand this conjecture by providing several equivalent statements. We then introduce the best effort made in the current literature towards solving this conjecture.
URL:https://colleges.claremont.edu/ccms/event/fractional-brownian-motion-small-increments-and-first-exit-time-from-one-sided-barrier-qidi-peng-cgu/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260127T121500
DTEND;TZID=America/Los_Angeles:20260127T131000
DTSTAMP:20260403T163719
CREATED:20260106T213106Z
LAST-MODIFIED:20260106T233659Z
UID:3942-1769516100-1769519400@colleges.claremont.edu
SUMMARY:The forbidden quiver of a link (Sam Nelson\, CMC)
DESCRIPTION:Virtual links can be represented as equivalence classes of Gauss diagrams under Reidemeister moves. The Forbidden Moves are moves which look plausible but change the virtual isotopy class of the knot or link — indeed\, virtual knots are all trivial if we allow forbidden moves. However\, virtual links remain non-trivial. In this talk we show how to think of these links as quivers and in the process\, define several polynomial invariants of link homotopy. This is joint work with Stella Shah (Scripps College).
URL:https://colleges.claremont.edu/ccms/event/antc-seminar-sam-nelson-cmc-4/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260129T161500
DTEND;TZID=America/Los_Angeles:20260129T171500
DTSTAMP:20260403T163719
CREATED:20260129T221950Z
LAST-MODIFIED:20260129T222543Z
UID:3979-1769703300-1769706900@colleges.claremont.edu
SUMMARY:Sampling from the proper colorings of a graph using a number of colors linear in the maximum degree in expected linear time (Mark Huber\, CMC)
DESCRIPTION:Abstract: A proper coloring of a graph is an assignment of colors from \( \{1\, 2\, \ldots\, k\} \) to each node of a graph such that no two nodes connected by an edge receive the same color. Let \( \Delta \) denote the maximum degree of the graph. If \( k \geq \Delta + 1 \) then at least one proper coloring always exists. However\, counting the number of proper colorings of an arbitrary graph is a #P-complete problem\, even when \( \Delta = 3 \). This means finding a polynomial time exact algorithm is unlikely to be found. On the other hand\, if a user can sample uniformly at random from the proper colorings of a graph\, then it becomes possible to approximately count the number of proper colorings to arbitrary precision in polynomial time. This work presents the first algorithm that has an expected running time that is linear in the size of the graph under the condition that \( k > 3.637 \Delta \). Joint work with Kritika Bhandari.
URL:https://colleges.claremont.edu/ccms/event/sampling-from-the-proper-colorings-of-a-graph-using-a-number-of-colors-linear-in-the-maximum-degree-in-expected-linear-time-mark-huber-cmc/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260130T110000
DTEND;TZID=America/Los_Angeles:20260130T121500
DTSTAMP:20260403T163719
CREATED:20260110T204139Z
LAST-MODIFIED:20260127T020408Z
UID:3944-1769770800-1769775300@colleges.claremont.edu
SUMMARY:CCMS Colloquium: John Baez (UCR)
DESCRIPTION:CCMS Colloquium invites you to a talk by John Baez (UCR)\n\n \nTitle: The mathematics of tuning systems\n \nAbstract: Leibniz said “Music is the pleasure the human mind experiences from counting without being aware that it is counting.”  The first step is choosing a tuning system — the frequency ratios between pitches in a scale.  Different kinds of music sound best in different tuning systems!  In music from the Middle Ages until today\, new musical styles have gone hand in hand with mathematical innovations in tuning systems.  Here I will focus on a few of the most important and beautiful Western systems\, from Pythagorean tuning to today’s reigning champion: equal temperament. Can you hear the difference?  What will come next?\n \n  \nBio:   \nJohn Baez is a mathematical physicist\, formerly at U. C. Riverside and currently the Maxwell Fellow at the University of Edinburgh.   He is known for the Cobordism Hypothesis connecting manifolds to higher categories.  In 1993 he began writing This Week’s Finds in Mathematical Physics\, which has been called the world’s first blog.   Since then he has helped start two well-known blogs: The n-Category Caf e\, a group blog on math and physics\, and Azimuth\, on mathematics and ecological issues.   He also writes a regular column in Notices of the American Mathematical Society.
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-john-baez-ucr/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260203T121500
DTEND;TZID=America/Los_Angeles:20260203T131000
DTSTAMP:20260403T163719
CREATED:20260129T172206Z
LAST-MODIFIED:20260129T215939Z
UID:3977-1770120900-1770124200@colleges.claremont.edu
SUMMARY:Relationships between skein algebras (Helen Wong\, CMC)
DESCRIPTION:We will examine the multiplicative structure of two skein algebras— the usual Kauffman bracket skein algebra of a surface (generated by loops) and a generalization of it due to Roger-Yang (generated by loops and arcs).   In joint work with Chloe Marple\, we found a homomorphism between the usual skein algebra for a closed torus and the Roger-Yang skein algebra for a twice-punctured annulus.   In this talk\, I’ll present some ways we used that homomorphism to do computations\, and whether there might be similar relationships between skein algebras of other surfaces. 
URL:https://colleges.claremont.edu/ccms/event/antc-talk-helen-wong-cmc-2/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260206T110000
DTEND;TZID=America/Los_Angeles:20260206T121500
DTSTAMP:20260403T163719
CREATED:20260110T215526Z
LAST-MODIFIED:20260127T164006Z
UID:3946-1770375600-1770380100@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Teal Witter (CMC)
DESCRIPTION:CCMS Colloquium invites you to a talk by Teal Witter (CMC)\n\n \nTitle:  Exactly Computing do-Shapley Values\n \n\nAbstract:  \nCausal questions lie at the heart of scientific inquiry\, from evaluating economic policies to determining medical treatments. Yet\, observational data alone is often insufficient due to the fundamental problem of causal inference: we cannot observe the counterfactual world where a specific intervention did not occur. Structural Causal Models (SCMs) offer a powerful solution by explicitly modeling the underlying mechanisms of a system. By formalizing data generation\, SCMs allow us to use the do-operator to rigorously simulate interventions\, answering questions like\, “If a patient were administered prednisone and made to stop smoking\, what would be their expected pain level?”\n\nHowever\, characterizing a system through individual queries is computationally daunting. As the number of features d grows\, the landscape of possible interventions scales exponentially (2^d). To extract interpretable insights from this combinatorial complexity\, we utilize the do-Shapley value\, a game-theoretic framework that attributes the complicated dynamics of an SCM to individual features.\n\nIn this talk\, I will present a new algorithmic approach that makes computing these values more tractable. We show that the causal landscape is structured into “irreducible sets”\, a building block where multiple interventions yield identical effects. By leveraging this structure\, we introduce an algorithm that computes do-Shapley values exactly\, with runtime that depends on the graph’s complexity rather than 2^d. We further propose an estimator that targets these sets directly\, producing more accurate estimates than prior work by several orders of magnitude or more.\n\nJoint work with Álvaro Parafita\, Tomas Garriga\, Maximilian Muschalik\, Fabian Fumagalli\, Axel Brando\, and Lucas Rosenblatt.\n\n \nBio: Teal is an Assistant Professor of Mathematics and Computer Science at Claremont McKenna College. His recent research explores randomized algorithms for problems in explainable AI and generative AI. More broadly\, he is interested in leveraging ideas from theoretical computer science and machine learning to design provably accurate algorithms. Before joining the consortium\, Teal completed his Ph.D. in Computer Science at New York University\, where he was supported by an NSF Graduate Research Fellowship. Prior to graduate school\, Teal attended Middlebury College.
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-teal-witter-cmc/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260207T100000
DTEND;TZID=America/Los_Angeles:20260207T115500
DTSTAMP:20260403T163719
CREATED:20251204T214629Z
LAST-MODIFIED:20260105T220646Z
UID:3937-1770458400-1770465300@colleges.claremont.edu
SUMMARY:GEMS February 7th Session
DESCRIPTION:This GEMS session will be facilitated by Professor Teal Witter from Claremont McKenna College.\n\n\nTitle: Who Can Write Down the Bigger Number?\n\n\nAbstract: \nIf you had fifteen seconds to write the largest distinct whole number possible on an index card\, what would you write? While most would look to the physical world for inspiration—counting the grains of sand in the Sahara or the atoms in the observable universe—we will explore much larger numbers. Our journey will take us beyond the limits of scientific notation\, moving from “power towers” and the mind-bending Ackermann function to the very edge of computer science. Ultimately\, we will arrive at the “Busy Beaver” sequence: numbers so unfathomably vast that they are theoretically uncomputable. Join us to explore the boundaries of language\, logic\, and the truly gargantuan.
URL:https://colleges.claremont.edu/ccms/event/gems-february-7th-session/
LOCATION:Shanahan B450\, Harvey Mudd College\, 301 Platt Blvd.\, Claremont\, 91711\, United States
CATEGORIES:GEMS
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260209T161500
DTEND;TZID=America/Los_Angeles:20260209T171500
DTSTAMP:20260403T163719
CREATED:20260205T210218Z
LAST-MODIFIED:20260205T210218Z
UID:3983-1770653700-1770657300@colleges.claremont.edu
SUMMARY:A BKM-type criterion for the 3D incompressible Euler equations (Mustafa Aydin\, USC)
DESCRIPTION:Abstract: The three-dimensional incompressible Euler equations describe the motion of an ideal fluid\, yet the mechanisms that govern the possible loss of regularity of smooth solutions remain only partially understood. A classical result of Beale\, Kato\, and Majda shows that if a smooth solution breaks down in finite time\, then the time integral of the vorticity’s supremum norm must diverge\, providing a sharp conditional criterion for regularity. \nIn this talk\, I will present a new blow-up criterion in the spirit of the Beale–Kato–Majda theorem that emphasizes a different form of control. Instead of requiring bounds on the full vorticity\, the criterion involves tangential derivatives of the velocity field\, and shows that smooth solutions persist as long as these derivatives remain appropriately bounded in time. The result holds in a variety of settings\, including the whole space\, periodic domains\, and domains with boundaries.
URL:https://colleges.claremont.edu/ccms/event/a-bkm-type-criterion-for-the-3d-incompressible-euler-equations-mustafa-aydin-usc/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Analysis Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260212T161500
DTEND;TZID=America/Los_Angeles:20260212T171500
DTSTAMP:20260403T163719
CREATED:20260207T012748Z
LAST-MODIFIED:20260207T014348Z
UID:3984-1770912900-1770916500@colleges.claremont.edu
SUMMARY:Analysis Seminar: Generalized Elmendorf’s Theorem in Context (Sofía Martínez Alberga\, Bryn Mawr College)
DESCRIPTION:Abstract: In general\, the objective of algebraic topology is to classify spaces using some algebraic invariants or up to some notion of equivalence. In the area of equivariant homotopy theory\, the goal is the same but now spaces equipped with a group action are considered and algebraic invariants of choice are homotopy groups. It turns out there is an analogous version of Whitehead’s theorem in the equivariant setting which in some sense motivates studying weak homotopy equivalences over homotopy equivalences. This talk will review some of these homotopical notions and introduce Elmendorf’s theorem. Proved in the eighties\, this theorem sheds some light on how one can better understand equivariant homotopical notions as functors from the orbit category of the group to the category of topological spaces. Also\, in this talk we will address how this perspective is used more modernly to understand better equivariant notions of other categories and to expand nonequivariant notions to equivariant ones.
URL:https://colleges.claremont.edu/ccms/event/analysis-seminar-generalized-elmendorfs-theorem-in-context-sofia-martinez-alberga-bryn-mawr-college/
LOCATION:Estella 2099\, Pomona College\, 610 N. College Ave.\, Claremont\, CA\, United States
CATEGORIES:Analysis Seminar
ORGANIZER;CN="Asuman Aksoy":MAILTO:asuman.aksoy@claremontmckenna.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260213T110000
DTEND;TZID=America/Los_Angeles:20260213T121500
DTSTAMP:20260403T163719
CREATED:20260210T023402Z
LAST-MODIFIED:20260210T023402Z
UID:3996-1770980400-1770984900@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Sofia Martinez Alberga (Bryn Mawr College)
DESCRIPTION:CCMS Colloquium invites you to a talk by Sofia Martinez Alberga (Bryn Mawr College)\n \nTitle: Stay in the Loop and Fun Group\n \nAbstract: In this talk\, we will discuss the goal of algebraic topology. After we will discuss a topological space that can be associated with any topological space\, say $X$\, and base point\, $b \in X$: the based loop space denoted $\Omega(X\, b)$. The loop space has some interesting algebraic structure that allows us to define an invariant for spaces. We will see how this invariant can be used more generally and when the action of a group is present on the space.\n \nBio: Dr. Sofía Martínez Alberga is a Research Associate at Bryn Mawr College working in algebraic topology. Originally born and raised in southern California\, she earned her Bachelor’s of Science in mathematics from the University of California\, Riverside in 2019 and that same year she won the NSF Graduate Research Fellowship and the Math Alliance Fellowship. Dr. Martínez Alberga earned her PhD from Purdue University and during graduate school\, she held roles like MSRI-Undergraduate Program graduate research assistant\, Enhancing Diversity Graduate Education summer program graduate mentor\, and Women In Science Programs (WISP) Liaison. Furthermore Dr. Martínez Alberga has been invited to attend and speak at conferences and seminars internationally and has organized and secured grants for sessions at major conferences such as JMM.
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-sofia-martinez-alberga-bryn-mawr-college/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260216T160000
DTEND;TZID=America/Los_Angeles:20260216T170000
DTSTAMP:20260403T163719
CREATED:20260121T185928Z
LAST-MODIFIED:20260121T190217Z
UID:3968-1771257600-1771261200@colleges.claremont.edu
SUMMARY:Explainability and Analysis of Variance (Zijun Gao\, USC)
DESCRIPTION:Abstract: Existing tools for explaining complex models and systems are associational rather than causal and do not provide mechanistic understanding. We propose a new notion called counterfactual explainability for causal attribution that is motivated by the concept of genetic heritability in twin studies. Counterfactual explainability extends methods for global sensitivity analysis (including the functional analysis of variance and Sobol’s indices)\, which assumes independent explanatory variables\, to dependent explanations by using a directed acyclic graphs to describe their causal relationship. Therefore\, this explanability measure directly incorporates causal mechanisms by construction. Under a comonotonicity assumption\, we discuss methods for estimating counterfactual explainability and apply them to a real dataset dataset to explain income inequality by gender\, race\, and educational attainment. \nBio: Zijun Gao is a tenure-track assistant professor in the Department of Data Sciences and Operations at USC Marshall Business School. She received her Ph.D. in Statistics from Stanford University in 2022 supervised by Professor Trevor Hastie. She served as a research associate in the Statistical Lab at the University of Cambridge from 2022 to 2023 hosted by Professor Qingyuan Zhao. Her research focuses on the estimation and inference problems in causal inference with heterogeneity\, with side interests in distribution learning\, selective inference\, and model evaluation. She also works on real-world data motivated topics\, with a specific emphasis on the applications in adaptive clinical trial and personalized medication.
URL:https://colleges.claremont.edu/ccms/event/explainability-and-analysis-of-variance-zijun-gao-usc/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260217T121500
DTEND;TZID=America/Los_Angeles:20260217T131000
DTSTAMP:20260403T163719
CREATED:20260121T181315Z
LAST-MODIFIED:20260211T173037Z
UID:3964-1771330500-1771333800@colleges.claremont.edu
SUMMARY:Summer of Math Discovery: Two research projects on combinatorial polytopes (Andrés R. Vindas Meléndez\, HMC)
DESCRIPTION:This is a talk in two parts covering two projects that the speaker mentored over the summer of 2025. The first project deals with the study of polytopes that arise from the convex hulls of stack-sorting on particular permutations. The second project deals with the study of symmetric edge polytopes of a finite simple graph\, a centrally symmetric lattice polytope whose vertices are defined by the edges of the graph. Both projects studied the (Euclidean\, relative\, or normalized) volumes of the respective combinatorially defined polytope.
URL:https://colleges.claremont.edu/ccms/event/antc-talk-andres-r-vindas-melendez-hmc/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260219T161500
DTEND;TZID=America/Los_Angeles:20260219T171500
DTSTAMP:20260403T163719
CREATED:20260216T012258Z
LAST-MODIFIED:20260216T012258Z
UID:4005-1771517700-1771521300@colleges.claremont.edu
SUMMARY:Analysis Seminar: Choquet simplices of groups and C*-algebras (Itamar Vigdorovich\, UCSD)
DESCRIPTION:Abstract: Let C be a compact convex set (in a locally convex topological vector space). By Choquet’s theorem\, every point in C is the barycenter of a probability measure supported on the extreme points. When this representing measure is unique\, C is called a simplex. \nSimplices arise naturally in various fields of mathematics: the space of invariant probability measures of a dynamical system is a simplex\, and so is the space of tracial states on a C*-algebra. In the group case\, the simplex of characters provides a framework for a non-commutative Fourier transform. \nI will also discuss results and phenomena for traces of free products\, fundamental groups of surfaces\, Kazhdan groups\, and related classes.
URL:https://colleges.claremont.edu/ccms/event/analysis-seminar-choquet-simplices-of-groups-and-c-algebras-itamar-vigdorovich-ucsd/
LOCATION:Estella 2099\, Pomona College\, 610 N. College Ave.\, Claremont\, CA\, United States
CATEGORIES:Analysis Seminar
ORGANIZER;CN="Asuman Aksoy":MAILTO:asuman.aksoy@claremontmckenna.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260220T110000
DTEND;TZID=America/Los_Angeles:20260220T121500
DTSTAMP:20260403T163719
CREATED:20260110T220450Z
LAST-MODIFIED:20260211T174926Z
UID:3948-1771585200-1771589700@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Mary Lou Zeeman (Bowdoin College)
DESCRIPTION:CCMS Colloquium invites you to a talk by Mary Lou Zeeman (Bowdoin College)\n\n \nTitle: A new framework for studying transient reactivity in two-dimensional systems.\n \nAbstract: Even if a linear system of ordinary differential equations (ODEs) has a globally attracting equilibrium\, solutions of the ODEs may grow arbitrarily large in the short-term before returning to the equilibrium in the long-term. This counter-intuitive phenomenon of transient amplification is called reactivity. It is especially important in ecological resilience and other applications where disturbances of a system may be transiently magnified to undesirable levels. In this talk we introduce a new framework for analyzing reactivity in two-dimensional linear systems of ODEs. While the eigenstructure of the system captures the long-term dynamics\, we use the new framework to define an orthostructure\, dual to the eigenstructure\, that captures transient reactivity dynamics of the system. By interweaving the eigen- and ortho-structures\, we are able to exactly quantify the maximum disturbance amplification possible.\n \nBio: Mary Lou Zeeman is the Wells Johnson Professor of Mathematics at Bowdoin College.  Her research is in dynamical systems with applications to biology\, sustainability and resilience. She is known for collaboratively building cross-disciplinary research communities focused on the health of the planet. She helped found and co-lead the Mathematics and Climate Research Network\, the Computational Sustainability Network and the SIAM Activity Group on Mathematics of Planet Earth. \n 
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-mary-lou-zeeman-bowdoin-college/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260227T110000
DTEND;TZID=America/Los_Angeles:20260227T121500
DTSTAMP:20260403T163719
CREATED:20260110T215752Z
LAST-MODIFIED:20260226T054131Z
UID:3947-1772190000-1772194500@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Harrison Li (HMC)
DESCRIPTION:CCMS Colloquium invites you to a talk by Harrison Li (HMC)\n\n \nTitle: Precise analysis of blocked randomized experiments\n \nAbstract: I recently finished a multi-year project with collaborators analyzing a blocked randomized experiment to evaluate the effectiveness of a government job training program for unemployment insurance (UI) recipients in Rhode Island. In presenting the results\, I will focus on some methodological considerations that arose organically in this context. I will start by providing an introduction to the potential outcomes framework in causal inference and show how it enables us to formulate a precise mathematical description of what exactly it is we want to estimate when running a randomized experiment. Then\, we will see some principled and less principled methods for performing this estimation in the setting of a block randomized experiment. Some directions for ongoing and future research will be discussed.\n \nBio: Harrison Li is in his first year as  an Assistant Professor of Mathematics at Harvey Mudd College. He comes to Claremont after finishing his graduate studies in statistics at Stanford University in 2025\, and previously worked full time as a quantitative trader on Wall Street. His research interests center around variance reduction in randomized experiments through experimental design and/or novel estimation procedures. He is also very passionate about developing sound statistical methodology in the service of other disciplines\, including climate science\, agronomy\, and economics\, and about exposing more students to the mathematical aspects of probability and statistics. \n 
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-harrison-li/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260302T161500
DTEND;TZID=America/Los_Angeles:20260302T171500
DTSTAMP:20260403T163719
CREATED:20260224T233444Z
LAST-MODIFIED:20260224T233444Z
UID:4007-1772468100-1772471700@colleges.claremont.edu
SUMMARY:Structure-Preserving Discretizations for Fokker–Planck Equations via the Energy Dissipation Law (Satish Chandran\, UCR)
DESCRIPTION:Abstract: We present a new approach for deriving structure-preserving numerical discretizations of Fokker-Planck equations by establishing a connection between the Fokker-Planck equation and its semi-discrete master equation at the level of the energy-dissipation law. We determine the transition rate in the master equation via the detailed balance condition and the spatial discretization of the continuous energy-dissipation law. This approach ensures that the semi-discrete master equation satisfies the detailed balance condition and converges to the correct equilibrium. In addition to recovering existing transition rates proposed in earlier works\, our framework uncovers new transition rates that have not been discussed in the current literature. This work is joint with Dr. Yiwei Wang (UCR).
URL:https://colleges.claremont.edu/ccms/event/structure-preserving-discretizations-for-fokker-planck-equations-via-the-energy-dissipation-law-satish-chandran-ucr/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260303T121500
DTEND;TZID=America/Los_Angeles:20260303T131000
DTSTAMP:20260403T163719
CREATED:20260302T023221Z
LAST-MODIFIED:20260302T023221Z
UID:4013-1772540100-1772543400@colleges.claremont.edu
SUMMARY:On a new version of Siegel’s lemma  (Lenny Fukshansky\, CMC)
DESCRIPTION:The classical Siegel’s lemma (1929) asserts the existence of a nontrivial integer solution to an underdetermined integer homogeneous linear system\, whose “size” is small as compared to the size of the coefficients of the system. Far-reaching generalizations of this theorem\, producing a full basis for the solution space\, were obtained over number fields by Bombieri & Vaaler (1983)\, and over the field of algebraic numbers by Roy & Thunder (1996)\, where the “size” was measured by a height function. We obtain a new version of Siegel’s lemma\, bridging the Bombieri & Vaaler and Roy & Thunder results in two ways: (1) our basis lies over a fixed number field as in Bombieri & Vaaler’s theorem; (2) our height-bound does not depend on the number field in question as in Roy & Thunder’s theorem. Our result does not imply the previously established ones and is not implied by them\, and our basis has some additional interesting properties. Our method is quite different from the previous ones\, using only linear algebra. Joint work with Max Forst.
URL:https://colleges.claremont.edu/ccms/event/on-a-new-version-of-siegels-lemma-lenny-fukshansky-cmc/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260306T110000
DTEND;TZID=America/Los_Angeles:20260306T121500
DTSTAMP:20260403T163719
CREATED:20260110T234502Z
LAST-MODIFIED:20260304T161508Z
UID:3950-1772794800-1772799300@colleges.claremont.edu
SUMMARY:CCMS Colloquium: Lihong Zhao (Kennesaw State University)
DESCRIPTION:CCMS Colloquium invites you to a talk by Lihong Zhao (Kennesaw State University)\n\n \nTitle: Capturing heterogeneity in malaria transmission: an age-structured model with immune feedback and seasonality\n \nAbstract: Malaria remains a major global health burden\, causing more than 600\,000 deaths and over 249 million cases globally each year. Heterogeneity in malaria transmission is a critical factor that influences the dynamics of disease emergence and the effectiveness of possible control strategies. In this talk\, I will present an age-structured model that couples vector-host epidemiological dynamics with immune feedback and how we use it to characterize seasonal malaria transmission and assess the impact of vaccination strategies. We also extend this model to explore how different mobility patterns and immunity profiles interact to impact the risk of severe infection and prevalence.\n \nBio: Dr. Lihong Zhao is an Assistant Professor of Mathematics at Kennesaw State University (KSU). Prior to her position at KSU\, she was a Visiting Assistant Professor in the Department of Mathematics at Virginia Tech and an NSF DIRAC-RTG postdoctoral fellow in the Department of Applied Mathematics at the University of California\, Merced. She develops and analyzes mathematical and computational models to examine questions in life sciences. Most of her work focuses on infectious disease epidemiology and ecology.
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-lihong-zhao-kennesaw-state-university/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260307T100000
DTEND;TZID=America/Los_Angeles:20260307T115500
DTSTAMP:20260403T163719
CREATED:20260207T052658Z
LAST-MODIFIED:20260307T001548Z
UID:3987-1772877600-1772884500@colleges.claremont.edu
SUMMARY:GEMS March 7th Session
DESCRIPTION:This GEMS session will be facilitated by Robbie Tran from Claremont Graduate University.\n\n\nTitle: Formulating Equations as a Medium for Digital Art and Design\n\n\nAbstract: \nAs we can utilize letters and words to write out mathematics (e.g. 2+2=4 can be written as “two plus two is equal to four”)\, this session seeks to explore the near reverse: how can we use mathematics to some extent graph letters and words? Rather\, could we formulate equations of curves that visually resemble text on a 2D-plane? If we include both conventional and nonconventional shapes too\, this question is not only an interesting curiosity\, but a question whose answer is quite prevalent in programs for computer graphics\, animation\, digital art\, and font design!\n\nWe will approach this question by highlighting and constructing Bézier curves\, which can approximate smooth curves by control (anchor) points on the plane. Furthermore\, this session will showcase the mathematics of these curves\, covering polynomials\, linear interpolation\, and parametrization (no prior knowledge assumed). Ultimately\, we will simulate how graphs of Bézier curves can be drawn for various letters and shapes by applying a recursive method called de Casteljau’s algorithm. Join us to explore an example of how mathematics can serve as a gateway to art and design!
URL:https://colleges.claremont.edu/ccms/event/gems-march-7th-session/
LOCATION:Shanahan 1480\, Harvey Mudd College\, 301 Platt Blvd.\, Claremont\, CA\, 91711\, United States
CATEGORIES:GEMS
ORGANIZER;CN="Teal Witter":MAILTO:raylen.witter@claremontmckenna.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260309T161500
DTEND;TZID=America/Los_Angeles:20260309T171500
DTSTAMP:20260403T163719
CREATED:20260303T213300Z
LAST-MODIFIED:20260310T191340Z
UID:4022-1773072900-1773076500@colleges.claremont.edu
SUMMARY:An Odd Estimator for Shapley Values (Teal Witter\, CMC)
DESCRIPTION:Abstract: The Shapley value is a ubiquitous framework for attribution in machine learning\, encompassing feature importance\, data valuation\, and causal inference. However\, its exact computation is generally intractable\, necessitating efficient approximation methods. While the most effective and popular estimators leverage the paired sampling heuristic to reduce estimation error\, the theoretical mechanism driving this improvement has remained opaque. In this work\, we provide an elegant and fundamental justification for paired sampling: we prove that the Shapley value depends exclusively on the odd component of the set function\, and that paired sampling orthogonalizes the regression objective to filter out the irrelevant even component. Leveraging this insight\, we propose OddSHAP\, a novel consistent estimator that performs polynomial regression solely on the odd subspace. By utilizing the Fourier basis to isolate this subspace and employing a proxy model to identify high-impact interactions\, OddSHAP overcomes the combinatorial explosion of higher-order approximations. Through an extensive benchmark evaluation\, we find that OddSHAP achieves state-of-the-art estimation accuracy.\n\nJoint work with Fabian Fumagalli\, Landon Butler\, Justin Singh Kang\, and Kannan Ramchandran.
URL:https://colleges.claremont.edu/ccms/event/an-odd-estimator-for-shapley-values-teal-witter-cmc/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260310T123000
DTEND;TZID=America/Los_Angeles:20260310T131000
DTSTAMP:20260403T163719
CREATED:20260119T182717Z
LAST-MODIFIED:20260307T023545Z
UID:3961-1773145800-1773148200@colleges.claremont.edu
SUMMARY:Hecke algebras and motives (Robert Cass\, CMC)
DESCRIPTION:Hecke algebras play a central role in both number theory and representation theory. While some Hecke algebras have explicit descriptions in terms of generators and relations\, others are understood through structure constants that encode multiplicities in tensor products of representations. In this talk\, I will discuss several projects with Thibaud van den Hove and Jakob Scholbach aimed at using geometry and motives to give a uniform categorification of Hecke algebras. Along the way\, we will encounter the geometric Satake equivalence\, Gaitsgory’s central functor\, and Iwahori-Whittaker models.
URL:https://colleges.claremont.edu/ccms/event/antc-talk-robert-cass-cmc-2/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260313T110000
DTEND;TZID=America/Los_Angeles:20260313T121500
DTSTAMP:20260403T163719
CREATED:20260110T234636Z
LAST-MODIFIED:20260313T054744Z
UID:3951-1773399600-1773404100@colleges.claremont.edu
SUMMARY:NO CCMS Colloquium: Pi Day at CMC
DESCRIPTION:No lecture today. \n  \nQuantitative and Computing Lab (QCL) Math Club Pi Day celebration at Claremont McKenna College at Kravis Lower Court from 11am to 12:30pm. \n 
URL:https://colleges.claremont.edu/ccms/event/ccms-colloquium-2/
LOCATION:Davidson Lecture Hall\, CMC\, 340 E 9th St\, Claremont\, CA\, 91711\, United States
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260320T110000
DTEND;TZID=America/Los_Angeles:20260320T121500
DTSTAMP:20260403T163719
CREATED:20260110T234749Z
LAST-MODIFIED:20260110T234749Z
UID:3952-1774004400-1774008900@colleges.claremont.edu
SUMMARY:NO CCMS Colloquium - SPRING BREAK
DESCRIPTION:
URL:https://colleges.claremont.edu/ccms/event/no-ccms-colloquium-spring-break/
LOCATION:CA
CATEGORIES:Colloquium
ORGANIZER;CN="Sam Nelson":MAILTO:snelson@cmc.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260323T161500
DTEND;TZID=America/Los_Angeles:20260323T171500
DTSTAMP:20260403T163719
CREATED:20260320T193527Z
LAST-MODIFIED:20260320T193527Z
UID:4056-1774282500-1774286100@colleges.claremont.edu
SUMMARY:A Regularity Criterion for the 3-D Navier-Stokes Equations Based on Finitely Many Observations (Abhishek Balakrishna\, USC)
DESCRIPTION:Abstract: This talk presents a regularity criterion for the three-dimensional Navier–Stokes equations based on finitely many observations of the flow. Motivated by data assimilation\, we study a nudging algorithm that incorporates coarse spatial measurements through general interpolation operators. \nWe show that suitable conditions on the observed data guarantee global regularity of the associated system and yield an exponential tracking property. As a consequence\, we obtain a new regularity criterion for weak solutions formulated entirely in terms of finitely many observables\, covering modal\, volume\, and nodal measurements.
URL:https://colleges.claremont.edu/ccms/event/a-regularity-criterion-for-the-3-d-navier-stokes-equations-based-on-finitely-many-observations-abhishek-balakrishna-usc/
LOCATION:Emmy Noether Room\, Estella 1021\, Pomona College\,\, 610 N. College Ave.\, Claremont\, CA\, 91711\, United States
CATEGORIES:Applied Math Seminar
ORGANIZER;CN="Ryan Aschoff":MAILTO:ryan.aschoff@cgu.edu
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260324T121500
DTEND;TZID=America/Los_Angeles:20260324T131000
DTSTAMP:20260403T163719
CREATED:20260209T235439Z
LAST-MODIFIED:20260226T211019Z
UID:3991-1774354500-1774357800@colleges.claremont.edu
SUMMARY:Computing certificates for complete positivity (Achill Schürmann\, University of Rostock)
DESCRIPTION:A key problem in computer proofs based on solutions from copositive optimization\, is checking whether or not a given quadratic form is completely positive or not. In this talk we describe the first known algorithm for arbitrary rational input. It is based on a suitable adaption of Voronoi’s Algorithm and the underlying theory from positive definite to copositive quadratic forms. We observe several similarities with the classical theory\, but also some differences\, in particular for three and more variables. A key element and currently the main bottleneck in our algorithm is an adapted shortest vector computation\, asking for all nonnegative integer vectors attaining the copositive minimum of a given copositive quadratic form. \n(based on joint work with Valentin Dannenberg\, Alexander Oertel\, Mathieu Dutour Sikiric and Frank Vallentin)
URL:https://colleges.claremont.edu/ccms/event/antc-talk-achill-schurmann-university-of-rostock/
LOCATION:Estella 2099
CATEGORIES:Algebra / Number Theory / Combinatorics Seminar
END:VEVENT
END:VCALENDAR