Published on Department of Mathematics Calendar (https://calendar.math.yale.edu)

Week of March 1, 2026

March 2, 2026
Geometric Analysis Learning Seminar [3]	Regularity of Einstein 5-manifolds via 4-dimensional gap theorems	Yiqi Huang - MIT	3:45pm - KT 906
Geometry, Symmetry and Physics [4]	The constant sheaf on Bun_G	Kenta Suzuki - Princeton University	4:30pm - KT 801

March 3, 2026
Geometric Analysis Learning Seminar [3]	Geometric Analysis Learning Seminar		10:30am - KT 801

March 5, 2026
Analysis [5]	Soliton Resolution Conjecture for the energy-critical heat equation	Shrey Aryan - MIT	4:00pm - KT 201
Quantum Topology and Field Theory [6]	Quantum algebras from generalized Poisson sigma models	Keyou Zeng - CMSA Harvard	4:30pm - KT 801

March 6, 2026
Learning seminar on Groups, Geometry and Dynamics [7]	Lattices, fundamental domains and Ratner's orbit closure theorem.	Jannik Westermann -	4:00pm - KT 801 or KT217

Abstracts

Week of March 1, 2026

March 2, 2026
Geometric Analysis Learning Seminar [3]	Regularity of Einstein 5-manifolds via 4-dimensional gap theorems	3:45pm - KT 906	We refine the regularity of noncollapsed limits of Einstein 5-manifolds. In particular, we prove uniqueness of tangent cones along the full top stratum of singular set and show that the entire singular set is contained in a countable union of bi-Lipschitz curves and points. Moreover, we establish that thesingular curve carries a real-analytic Einstein orbifold structure and is a geodesic in the limit space. The proofs rely on new 4-dimensional gap theorems for spherical and hyperbolic Einstein orbifolds. This is joint work with Tristan Ozuch.
Geometry, Symmetry and Physics [4]	The constant sheaf on Bun_G	4:30pm - KT 801	Given a smooth projective curve X and a reductive group G, the geometric Langlands equivalence proved by Gaitsgory, Raskin et al. (roughly) gives an equivalence between sheaves on the stack Bun_G(X) of G-bundles on X (automorphic side) and quasi-coherent sheaves on the stack of G^-local systems on X (spectral side). To compute the image of an object under the geometric Langlands equivalence, one usually bootstraps from the Whittaker model. This method fails for the constant sheaf on Bun_G(X), which is “maximally singular.” Still, we will compute its image under the equivalence, confirming a conjecture of V. Lafforgue. As a consequence, when X is over F_q we find a spectral description for the constant function on Bun_G(X)(F_q

March 3, 2026
Geometric Analysis Learning Seminar [3]	Geometric Analysis Learning Seminar	10:30am - KT 801	TBA

March 5, 2026
Analysis [5]	Soliton Resolution Conjecture for the energy-critical heat equation	4:00pm - KT 201	The Soliton Resolution Conjecture predicts that finite-energy solutions to nonlinear dispersive PDEs asymptotically decouple into a sum of stationary solutions, called solitons, and free radiation, with an error that goes to zero in the energy norm. In this talk, we discuss the conjecture for the energy-critical nonlinear heat equation in dimension $d\geq 3$ and present its proof in the radial case. If time permits, we will also discuss recent progress in the non-radial setting, with potential applications to other geometric flows such as the Yang-Mills heat flow.
Quantum Topology and Field Theory [6]	Quantum algebras from generalized Poisson sigma models	4:30pm - KT 801	Poisson sigma models sit at the intersection of deformation theory, geometry, and quantum field theory; specifically, the perturbative expansion of the two-dimensional Poisson sigma model with boundary is known to recover Kontsevich’s deformation quantization formula. In this talk, we introduce a higher-dimensional holomorphic–topological generalization of Poisson sigma models and explain their connections to the deformation quantization (or obstruction) of holomorphic–topological factorization algebras. This construction can be viewed as a field-theoretic incarnation of the higher Deligne conjecture. We also explain how these models relate to the construction of Hopf-type algebras via Koszul duality, and explore examples related to the quantization of Lie bialgebras, W-algebras, and Yangians.

March 6, 2026
Learning seminar on Groups, Geometry and Dynamics [7]	Lattices, fundamental domains and Ratner's orbit closure theorem.	4:00pm - KT 801 or KT217

Links
[1] https://calendar.math.yale.edu/list/calendar/grid/week/2026-W09 [2] https://calendar.math.yale.edu/list/calendar/grid/week/2026-W11 [3] https://calendar.math.yale.edu/seminars/geometric-analysis-learning-seminar [4] https://calendar.math.yale.edu/seminars/geometry-symmetry-and-physics [5] https://calendar.math.yale.edu/seminars/analysis [6] https://calendar.math.yale.edu/seminars/quantum-topology-and-field-theory [7] https://calendar.math.yale.edu/seminars/learning-seminar-groups-geometry-and-dynamics [8] https://calendar.math.yale.edu/list/calendar/grid/week/abstract/2026-W09 [9] https://calendar.math.yale.edu/list/calendar/grid/week/abstract/2026-W11