Riemann-Roch space representations from bad hyperelliptic curves: questions and computations
نویسنده
چکیده
Much of this is joint work with Amy Ksir, the rest is " in progress ". 1 Motivation Let F = C temporarily and let X be a non-singular projective curve of genus > 1 with automorphism group G. This group acts on the vector space of differentials on X and, more generally, on the Riemann-Roch space of a G-equivariant divisor D. Question: What are these representations? Can we compute their char-acter? Their multiplicities? For the group action on the differentials, the trace of an individual element can be computed using the Eichler trace formula. For more general character computations, we use the Borne character formula.
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