Tittle: Partial regularity for Lipschitz solutions to the minimal surface system Abstract: The minimal surface system is the Euler-Lagrange system for the area functional of a high codimension graph and reduces to the minimal surface equation in the case that the codimension is one. Though the regularity theory for the minimal surface equation is well understood, […]
Tikhonov regularization is a widely used technique in solving inverse problems that can enforce prior properties on the desired solution. In this talk, I will present a Krylov subspace based iterative method for solving linear inverse problems with general-form Tikhonov regularization term $x^top M x$ , where $M$ is a positive semidefinite matrix. An iterative […]
Title: The local theta correspondence and functoriality Abstract: In a letter to Howe, Langlands conjectured that the local theta correspondence is an instance of Langlands functoriality, e.g., it should preserve L-packets. Unfortunately, this was false. As a remedy, Adams conjectured that instead of L-packets, the local theta correspondence should preserve Arthur packets. Mœglin showed that […]
Title: Towards A-theory of orbifoldsAbstract: Waldhausen's A-theory of spaces — an extension of Quillen's higher algebraic K-theory of rings — is central to the study of moduli spaces of manifolds. In this talk, we will discuss a generalization of A-theory that takes as input an orbifold and which we expect to have rich geometric applications in analogy with the manifold setting. An orbifold is […]
Title: An Euler system of Heegner type Abstract: In this talk, I will present the result of Cornut in his paper "An Euler system of Heegner type" where he constructed the Kolyvagin Euler system associated with the spherical pair (SO(2n+1),U(n)) by reducing the local Horizontal norm relation to a divisibility result on integral Hecke module, […]
Title: The Lawson-Osserman conjecture for the minimal surface systemAbstract: In their seminal work on the minimal surface system, Lawson and Osserman conjectured that Lipschitz graphs that are critical points of the area functional with respect to outer variations are also critical with respect to domain variations. We will discuss the proof of this conjecture for […]
Title: Relative Satake isomorphism and Euler systems Abstract: Starting from the inversion formula for the relative Satake isomorphism due to Sakellaridis, we observe a simple additional divisibility property. We will then explain how this gives a computation-free construction of Euler systems in some settings. This is joint work with Li Cai and Yangyu Fan.
Title: Towards the quantum exceptional series Abstract: Many Lie algebras fit into discrete families like GL(n), On, Spn. By work of Brauer, Deligne and others, the corresponding tensor categories fit into continuous familes GL(t) and OSp(t). A similar story holds for quantum groups, so we can speak of two parameter families GL(t)_q and OSp(t)_q. Thesetensor categories […]
Title: The Nevo-Thangavelu spherical maximal function on two step nilpotent Lie groups.Consider R^d times R^m with the group structure of a 2-step Carnot Lie group and natural parabolic dilations. The maximal operator originally introduced by Nevo and Thangavelu in the setting of the Heisenberg groups is generated by (noncommutative) convolution associated with measures on […]
Title: Minimal Exponent of Local Complete Intersection Subvarieties.Abstract: Classification of singularities is an interesting problem in many areas of algebraic geometry, like the minimal model program. One classical approach is to assign to a singular subvariety a rational number, its log canonical threshold. For complex hypersurface singularities, this invariant has been refined by M. Saito to the […]
Title: Asymptotic Enumerativity of Tevelev Degrees.Abstract: A Tevelev degree is a type of Gromov-Witten invariant where the domain curve is fixed in the moduli. After reviewing the basic definitions and previously known results, I will report on joint work with Lehmann, Lian, Riedl, Starr, and Tanimoto, where we improve the Lian-Pandharipande bound on asymptotic enumerativity of Tevelev […]
Title: On the Gan-Gross-Prasad conjecture for unitary groups Abstract: The Gan-Gross-Prasad conjecture stipulates the existence of relations between the central values of certain L-functions and some automorphic periods on classical groups. It can be seen as a higher rank generalization of a famous formula of Waldspurger for toric periods on GL(2). In this talk, I […]
Title: Transfer operators for the relative trace formula. (Cont.) Abstract: Last time I presented an explicit formula for transfer operators that relate test measures and characters between the double quotients HG/H, for any rank-one homogeneous space G/H and the Whittaker model of SL(2) or PGL(2). In this talk, I will give a possible explanation for […]
Title: Optimal observability times for wave and Schrodinger equations on really simple domainsAbstract: Observability for evolution equations asks: if I take a partial measurement in a system, can it “see” some physical quantity, such as energy? In a series of papers with E. Stafford, Z. Lu, and S. Carpenter, we showed that energy for the […]
Title: Shimura Varieties and Eigensheaves Abstract: The cohomology of Shimura varieties is a fundamental object of study in algebraic number theory by virtue of the fact that it is the only known geometric realization of the global Langlands correspondence over number fields. Usually, the cohomology is computed through very delicate techniques involving the trace formula. […]
Rather than a seminar talk, this week we will meet to brainstorm on the relation between Euler systems and harmonic analysis.