This paper completes the construction of $p$ adic $L$ functions for unitary groups. More precisely, in Harris, Li and Skinner [‘ $p$ adic $L$ functions for unitary Shimura varieties. I. Construction of the Eisenstein measure’, Doc. Math. Extra Vol. (2006), 393–464 (electronic)], three of the authors proposed an approach to constructing such $p$ adic $L$ functions (Part I). Building on more recent results, including the first named author’s construction of Eisenstein measures and $p$ adic differential operators [Eischen, ‘A $p$ adic Eisenstein measure for unitary groups’, J. Reine Angew. Math. 699 (2015), 111–142; ‘ $p$ adic differential operators on automorphic forms on unitary groups’, Ann. Inst. Fourier (Grenoble) 62 (1) (2012), 177–243], Part II of the present paper provides the calculations of local $\unicode[STIX]{x1D701}$ integrals occurring in the Euler product (including at $p$ ). Part III of the present paper develops the formalism needed to pair Eisenstein measures with Hida families in the setting of the doubling method.
Entire Theta Operators at Unramified Primes
Abstract Starting with the work of Serre, Katz, and SwinnertonDyer, theta operators have played a key role in the study of $p$adic and $\textrm{mod}\; p$ modular forms and Galois representations. This paper achieves two main results for theta operators on automorphic forms on PELtype Shimura varieties: (1) the analytic continuation at unramified primes $p$ to the whole Shimura variety of the $\textrm{mod}\; p$ reduction of $p$adic Maass–Shimura operators a priori defined only over the $\mu $ordinary locus, and (2) the construction of new $\textrm{mod}\; p$ theta operators that do not arise as the $\textrm{mod}\; p$ reduction of Maass–Shimura operators. While the main accomplishments of this paper concern the geometry of Shimura varieties and consequences for differential operators, we conclude with applications to Galois representations. Our approach involves a careful analysis of the behavior of Shimura varieties and enables us to obtain more general results than allowed by prior techniques, including for arbitrary signature, vector weights, and unramified primes in CM fields of arbitrary degree.
 Award ID(s):
 1751281
 Publication Date:
 NSFPAR ID:
 10280386
 Journal Name:
 International Mathematics Research Notices
 ISSN:
 10737928
 Sponsoring Org:
 National Science Foundation
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