$p$-adic $L$-functions and unitary completions of representations of $p$-adic reductive groups
$p$-adic $L$-functions and unitary completions of representations of $p$-adic reductive groups
复制标题
$p$-adic $L$-$p$-adic 还原群表示的函数和酉完成
DOI:
10.1215/00127094-8230018
复制
发表时间:
2005
影响因子:
2.5
通讯作者:
M. Emerton
中科院分区:
文献类型:
--
作者:
M. Emerton
In the first half of the paper we introduce the notion of the universal unitary completion of a continuous representation of a p-adic reductive group on a locally convex p-adic vector space, and prove that such a completion exists under appropriate hypotheses. The problem of studying unitary completions has been raised by Breuil in connection with his work on a possible “p-adic local Langlands correspondence” for GL2, and we relate our construction to certain conjectures of Breuil for the group GL2(Qp). In particular, we show that the universal unitary completion of the locally analytic parabolic induction of a locally algebraic character coincides with the universal unitary completion of the corresponding locally algebraic induction, provided that the character being induced satisfies a “non-critical slope” condition. (See Proposition 2.5 below.) In the second half of the paper we consider a certain unitary Banach space representation of GL2(Qp) obtained by p-adically completing the cohomology of classical modular curves. The mere existence of this representation implies that those locally algebraic parabolically induced representations of GL2(Qp) that arise from classical finite slope newforms have a non-trivial universal unitary completion (verifying a conjecture of Breuil for these representations), while applying Proposition 2.5 in this context enables us to give a new construction of p-adic L-functions attached to p-stabilized newforms of non-critical slope. Combining our construction with a representation theoretic definition of L-invariants due to Breuil [5], we are able to give a simple proof of the Mazur-Tate-Teitelbaum exceptional zero conjecture (in terms of Breuil’s definition of the L-invariant). The object of this note is two-fold. In its first half we consider the following problem in the representation theory of p-adic groups: When does a topologically irreducible continuous representation of a p-adic reductive group G on a p-adic topological vector space (perhaps satisfying some additional hypotheses) admit an embedding into a unitary representation of G on a p-adic Banach space? If G = GL2(Qp) and the representation considered is admissible locally algebraic, this problem has been raised by Breuil in connection with his ideas on a “p-adic Local Langlands correspondence for GL2(Qp)” [4, 5]. In the second half of the paper we explain a representation theoretic point of view on p-adic L-functions attached to modular forms. As an application, we prove a version of the Mazur-Tate-Teitelbaum exceptional zero conjecture [16, p. 46], using the representation theoretic definition of the L-invariant given by Breuil in [5] (which provides a reinterpretation of the definition given by Darmon [9] and Orton [18] in the weight two and higher weight cases respectively). The two halves of the paper are more closely related than they might appear at first glance. Indeed, the local tools discussed in the first half play a vital role in the The author would like to acknowledge the support of the National Science Foundation (award number DMS-0401545)