K 3 Surfaces with Involution , Equivariant
نویسندگان
چکیده
In [59], we introduced an invariant of K3 surfaces with involution, which we obtained using equivariant analytic torsion. This invariant gives rise to a function on the moduli space of K3 surfaces with involution and is expressed as the Petersson norm of an automorphic form characterizing the discriminant locus. In this paper, we study the structure of this automorphic form. Under certain assumption, we prove that the automorphic form is expressed as the product of a certain Borcherds lift and the Igusa form.
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