Title: Covers of P^1 and number fields Abstract: Let $n$ be an integer. Via the Minkowski embedding, an order $mathcal{O}$ in a degree $n$ number field can be seen as a lattice. Similarly, given a degree $n$ cover of $mathbb{P}^1$, the pushforward of the structure sheaf is an interesting rank $n$ vector bundle on $mathbb{P^1}$. […]
Title: Kloosterman sums in representation theory of GL(n, Fq) Abstract: Given a "nice" irreducible representation of GL(n, Fq), one can define a special matrix coefficient attached to it, called the Bessel function. Often Kloosterman sums show up as special values of these Bessel functions. In this talk, I will first explain my previous results regarding […]
Title: First explicit reciprocity law for unitary Friedberg—Jacquet periods Abstract: In the early 2000's, Bertolini and Darmon introduced a new technique to bound Selmer groups of elliptic curves via level raising congruences. This was the first example of what is now termed a "bipartite Euler system", and over the last decade we have seen many […]
Title: Unipotent Representations of Real Reductive Groups and Mixed Hodge Modules Abstract: Let Pi(G) denote the set of irreducible unitary representations of a semisimple Lie group G. A fundamental problem in representation theory is to describe the structure of this set. In previous joint work with Losev and Matvieievskyi, we have defined a class of […]
Title: Nonabelian Fourier kernels on SL₂ and GL₂ Abstract: I will present my collaborative work with Ngô on explicit formulas for the nonabelian Fourier kernels on SL₂ and GL₂, as conjectured by Braverman and Kazhdan. Additionally, I will discuss its connection to the orbital Hankel transform studied by Ngô.
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: 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: 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: 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. […]
Title: p-adic L-functions for GSp(4)times GL(2) Abstract: I'll explain a construction of p-adic L-functions for GSp(4)times GL(2) by using Furusawa's integral and the proof of its interpolation formula. I'll describe how local functional equations are used to compute the zeta intgerals at p and how the archimedean integrals are computed by using Yoshida lifts together […]
Title: Towards Bezrukavnikov's geometrization of affine Hecke algebras in mixed-characteristics Abstract: Let G be a connected reductive group over a p-adic field. Kazhdan and Lusztig established an isomorphism between the extended affine Hecke algebra of G and certain equivariant K-group of the Steinberg variety of the Langlands dual group of G. This isomorphism plays a crucial […]
Title: Beyond Endoscopy via Poisson Summation for $GL(2,K)$ Abstract: Langlands proposed a strategy called Beyond Endoscopy to prove the principle of functoriality, which is one of the central questions of present day mathematics. Langlands strategy of beyond endoscopy is a two-step process where the first step isolates the packets of cuspidal automorphic representations whose $L$-functions […]