Geometry and Mathematical Physics seminar
2026-11-19 16:30 - 17:30 (America/New_York) | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Geometry and Mathematical Physics seminar
Speaker: Joshua Greene, Boston College

Member Seminar
2026-11-20 12:00 - 13:00, 2026-12-04 12:00 - 13:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States

Colloquium
2026-11-23 16:30 - 17:30, 2026-11-30 16:30 - 17:30, 2026-12-07 16:30 - 17:30 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States

Geometry and Quantum Theory Seminar
2026-11-24 16:15 - 18:00, 2026-12-01 16:15 - 18:00 | Science Center 507, 1 Oxford Street, Cambridge, 02138
Joint Math/CMSA Geometry and Quantum Theory Seminar

New Technologies in Mathematics Seminar
2026-11-25 14:00 - 15:00, 2026-12-02 14:00 - 15:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
New Technologies in Mathematics Seminar
Speaker: tba

AI for the Working Mathematician
2026-12-02 16:30 - 17:30 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
AI for the Working Mathematician
Speaker: Mark Selke, Harvard
Title: TBA

Geometry and Mathematical Physics seminar
2026-12-03 16:30 - 17:30 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Geometry and Mathematical Physics seminar
Speaker: Paul Feehan, Rutgers University
Title: TBA

Differential Geometry and Physics Seminar
2026-12-03 16:30 - 17:30 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States

Mathematical Economics Seminar
2026-12-08 14:00 - 16:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Speaker: Karun Adusumilli, University of Pennsylvania,
Title: Continuous Time Asymptotic Representations for Adaptive Experiments
Abstract: This article develops a continuous-time asymptotic framework for analyzing adaptive experiments—settings in which data collection and treatment assignment evolve dynamically in response to incoming information. Akey challenge in analyzing fully adaptive experiments, where the assignment policy is updated after each observation, is that the sequence of policy rules often lack a well-defined asymptotic limit. To address this, we focus instead on the empirical allocation process, which captures the (normalized) number of observations assigned to each treatment over time. We show that, under general conditions, any adaptive experiment and its associated empirical allocation process can be approximated by a limit experiment defined by Gaussian diffusions with unknown drifts and a corresponding continuous-time allocation process. This limit representation facilitates the analysis of optimal decision rules by reducing the dimensionality of the state-space and exploiting the tractability of Gaussian diffusions. We apply the framework to derive optimal estimators, analyze in-sample regret for adaptive experiments, and construct e-processes for anytime-valid inference. Notably, we introduce the first definition of any-time and any-experiment valid inference for multi-treatment settings.
Speaker: Toru Kitagawa, Brown University,
Title: TBA
Speaker: Chen Qiu, Cornell University,
Title: Local Asymptotics for Treatment Choice with Partial Identification
Abstract: We provide a new asymptotic framework to derive approximately optimal treatment assignments when sampling noise from data is compounded by fundamental uncertainty due to partial identification. We recenter the reduced-form parameter around its least-favorable configuration and consider drifting parameter sequences that yield both diminishing levels of sampling uncertainty and of partial identification. We characterize the limiting decision problem as a normal location shift model with a suitable limiting identified set. We apply our results to treatment choice problems with contaminated outcomes, to robust welfare analyses with partially identified consumer surplus, and to the problem of aggregating experimental estimates for policy adoption.

Stable Homotopy Theory and Arithmetic Geometry
2027-02-15 08:00 - 2027-05-15 17:00 | CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Stable Homotopy Theory and Arithmetic Geometry
Dates: Feb 15–May 15, 2027
Location: Harvard CMSA, 20 Garden St, Cambridge MA
This program will focus on interactions between stable homotopy theory and arithmetic geometry. In recent years, ideas from homotopy theory have begun to play an important role in areas such as p-adic cohomology, prismatic methods, and aspects of the Langlands program, while techniques from arithmetic geometry have led to new insights and computations in chromatic homotopy theory. Despite this growing overlap, researchers in the two areas often use different languages and tools. A central goal of the program is to make these ideas more accessible across fields and to encourage collaborations around shared problems.
The program will run from February 15 to May 15 and will be built around research and informal collaboration. It will begin with a short introductory bootcamp, followed by two focused workshops (one near the start and one toward the end), a weekly seminar with broadly accessible talks, and a weekly open-problem session. Most of the time will be left open for discussion and joint work among participants, aiming to spark new projects and longer-term connections between the two communities.
The program will include:
(1) a bootcamp during the week Feb. 22–26, consisting of introductory lectures on both subjects;
(2) two research workshops—one during Mar. 1–5 and one during May 3–7—highlighting current developments, especially those at the interface of the two areas;
(3) a weekly seminar featuring talks of broad relevance to participants; and
(4) a weekly open-problem seminar aimed at proposing and developing collaborative research directions, both for the duration of the program and beyond.
Register Online

Organizers: Tomer Schlank (Harvard), Jared Weinstein (Boston University), Mark Kisin (Harvard), Jeremy Hahn (MIT), Lucas Mann (Münster)

Stable Homotopy Theory and Arithmetic Geometry Boot Camp
2027-02-22 09:00 - 2027-02-26 17:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Stable Homotopy Theory and Arithmetic Geometry Boot Camp
Dates: February 22-26, 2027

Stable Homotopy Theory and Arithmetic Geometry Workshop I
2027-03-01 09:00 - 2027-03-05 17:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Stable Homotopy Theory and Arithmetic Geometry Workshop I
Dates: March 1–5, 2027

Seventh Annual Yip Lecture | L. Mahadevan, Harvard
2027-03-03 16:00 - 17:00 | MA
Sixth Annual Yip Lecture
Date: Wednesday, March 3, 2027
Time: 4:00–5:00 pm
Location: Harvard Science Center Hall D & via Zoom Webinar
Speaker: L. Mahadevan, Harvard

The Yip Lecture takes place thanks to the support of Dr. Shing-Yiu Yip.

2027 Ding Shum Lecture: Avi Wigderson, IAS
2027-03-31 16:00 - 17:00 | Harvard Science Center, 1 Oxford Street, Cambridge, MA, 02138
2027 Ding Shum Lecture
Date: Wednesday, March 31, 2027
Time: 4:00 pm
Location: Harvard Science Center Hall D & via Zoom Webinar

Speaker: Avi Wigderson, IAS

A reception will follow the talk in the Mathematics Department Austine & Chilton McDonnell Common Room, 4th floor, Science Center.

This event is made possible by the generous funding of Ding Lei and Harry Shum.

The Conformal Bootstrap and Mathematics
2027-04-05 - 2027-04-09 | CMSA 20 Garden Street Cambridge, Massachusetts 02138 United States
The Conformal Bootstrap and Mathematics
The conformal bootstrap is a method originating in physics that seeks to define and study conformal quantum field theories in two and higher dimensions. In recent years, surprising connections have emerged between the conformal bootstrap and several areas of mathematics, including the spectral theory of automorphic forms, the sphere packing problem, and related questions in geometry, analysis, and number theory. These developments suggest both that the conformal bootstrap “knows” a remarkable amount of mathematics, and that these mathematical structures can offer new ways of understanding quantum field theory.
This workshop will bring together experts from conformal field theory, number theory, spectral geometry, discrete geometry, and related fields to explore these emerging connections. One goal is to investigate how ideas and techniques from the conformal bootstrap can lead to new advances in mathematics. A complementary goal is to use insights from these mathematical disciplines to sharpen our understanding of conformal field theory and quantum field theory more broadly.
Organizers: James Bonifacio, University of Mississippi; Henry Cohn, MIT; Dalimil Mazáč, Institute of Theoretical Physics, Saclay; and Peter Sarnak, IAS

Stable Homotopy Theory and Arithmetic Geometry Workshop II
2027-05-03 09:00 - 2027-05-07 17:00 | CMSA Room G10, CMSA, 20 Garden Street, Cambridge, MA, 02138, United States
Stable Homotopy Theory and Arithmetic Geometry Workshop II
Dates: May 3–7, 2027

Quantum Fields, Analysis, and Geometry
2027-08-30 09:00 - 2028-05-05 17:00 | Hybrid – G10
Quantum Fields, Analysis, and Geometry
Dates: August 30, 2027 – May 5, 2028
Location: Harvard CMSA, 20 Garden Street, Cambridge MA
Quantum field theory (QFT) has long been a subject with a large influence on mathematics, yet there is still no unified mathematical framework that encompasses all viewpoints. Constructive QFT and Algebraic QFT—typified by the Wightman and Haag-Kastler axiom systems, respectively—have many achievements in relativistic and Euclidean QFT, but they do not include Wick-rotated theories on compact manifolds and so miss many of the geometric, topological, and algebraic developments of the past several decades. These developments include supersymmetric QFT and applications to geometry and topology, generalized symmetries in QFT, and a robust mathematical theory of topological QFTs. The more recent Segal and Costello-Gwilliam axiom systems do accommodate some of these developments, but they are largely disjoint from the analytic progress. Techniques from probability theory and stochastic PDE have been used to advance traditional constructive and algebraic QFT; they have also been applied to obtain rigorous results in two-dimensional conformal field theory and Euclidean lattice gauge theories. There has also been recent progress in quantum lattice systems, revealing surprising new bridges between operator algebras and topology.
This special year at CMSA aims to shape the direction of the field by bringing the analytic and geometric threads of mathematical QFT into closer contact. The program will gather a diverse group of mathematicians together with physicists who enjoy close interactions with mathematicians. The year will be organized around the four focus areas listed below. There will be several short courses and one weeklong workshop for each of these focus areas. All lectures will be hybrid.
FOCUS AREAS
First Semester

Axiomatic approaches to QFT
Symmetry, anomalies, and topology

Second Semester

Probabilistic methods in QFT
Supersymmetry, geometry, and moduli spaces

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We welcome long-term visitors as well as short-term visitors and online participants. If you would like to participate in the program, other than the workshops, please click here: Visitor Form
If you would like to be on a mailing list for information and announcements about this special year, please click here: Subscribe to the CMSA QFT Program Mailing List

Organizers:

Sourav Chatterjee (Stanford University)
Clay Cordova (University of Chicago)
Dan Freed (Harvard University)
Anton Kapustin (Caltech)
Constantin Teleman (University of California, Berkeley)
