Geometric approach to the local Jacquet-Langlands correspondence

A geometric Jacquet-Langlands correspondence for U(2) Shimura varieties

Let G be a unitary group over Q, associated to a CM-field F with totally real part F, with signature (1, 1) at all the archimedean places of F. For certain primes p, and X a Shimura variety associated to G with good reduction at p, we construct a stratification of the characteristic p fiber of X , whose closed strata are indexed by subsets S of the archimedean places of F. Certain closed strata...

The local Jacquet-Langlands correspondence via Fourier analysis

Let F be a locally compact non-Archimedean field, and let B/F be a division algebra of dimension 4. The JacquetLanglands correspondence provides a bijection between smooth irreducible representations π′ of B× of dimension > 1 and irreducible cuspidal representations of GL2(F ). We present a new construction of this bijection in which the preservation of epsilon factors is automatic. This is don...

Towards a geometric Jacquet-Langlands correspondence for unitary Shimura varieties

Let G be a unitary group over a totally real field, and X a Shimura variety associated to G. For certain primes p of good reduction for X, we construct cycles Xτ0,i on the characteristic p fiber of X. These cycles are defined as the loci on which the Verschiebung map has small rank on particular pieces of the Lie algebra of the universal abelian variety on X. The geometry of these cycles turns ...

The Jacquet-Langlands correspondence via `-adic uniformization

THE JACQUET-LANGLANDS CORRESPONDENCE FOR GL2 Contents

1.1. Matching regular semisimple conjugacy classes. Let X(F ) = F × F×, viewed as the space of semisimple conjugacy classes in GL2(F ) via GL2(F ) → X(F ) sending γ 7→ (Tr(γ),det(γ)). Similarly we have D× → X(F ) sending γ′ 7→ (TrD/F (γ),NmD/F (γ′)), where TrD/F and NmD/F mean reduced trace and norm. For regular semisimple γ ∈ GL2(F ) and γ′ ∈ D×, we write γ ∼ γ′ if they have the same image in ...