Modular Lagrangians and the theta multiplier

Autor: Dennis Lee Johnson, John J. Millson
Rok vydání: 1990
Předmět:
Zdroj: Inventiones Mathematicae. 100:143-165
ISSN: 1432-1297
0020-9910
DOI: 10.1007/bf01231183
Popis: Let V be a free module over Z/4 of rank 2 n and let (,) be a non-singular skew form on V. Let F" denote the reduction of V modulo 2 and let Q be a hyperbolic (i.e. Arf invariant zero) quadratic form on P with (,) as associated bilinear form. We let A(V) denote the set of oriented Lagrangians (i.e. free totally-isotropic submodules of rank n) in V and Ao(V)cA(V) the subset of those L in A(V) whose reductions modulo 2 are totally isotropic for Q. We call such an L an oriented isotropic Lagrangian. We will study a certain function m on Ao(V)x Ao(V) with values in the group of fourth roots of unity. The function m is skew-symmetric (m(M, L)= re(L, M)-t) and is a 1-cocycle. By this
Databáze: OpenAIRE
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