Sur les paquets d'Arthur des groupes classiques r\'eels

TL;DR

This paper investigates Arthur packets for real classical groups, providing explicit descriptions and establishing the multiplicity one property through cohomological induction and endoscopic transfer techniques.

Contribution

It offers a new construction of Arthur packets from unipotent packets on Levi factors using cohomological induction, with a focus on real classical groups.

Findings

Construction of Arthur packets from unipotent packets

Proof of multiplicity one property for real classical groups

Establishment of commutativity between cohomological induction and transfer

Abstract

This article is part of a project which consists of investigating Arthur packets for real classical groups. Our goal is to give an explicit description of these packets and to establish the multiplicity one property (which is known to hold for $p$-adic and complex groups). The main result in this paper is a construction of packets from unipotent packets on $c$-Levi factors using cohomological induction. An important tool used in the argument is a statement of commutativity between cohomological induction and spectral endoscopic transfer.