A Density Result for Real Hyperelliptic Curves
نویسنده
چکیده
Let {∞+,∞−} be the two points above ∞ on the real hyperelliptic curve H : y = (x − 1) ∏2g i=1(x− ai). We show that the divisor ([∞ ]− [∞−]) is torsion in Jac J for a dense set of (a1, a2, . . . , a2g) ∈ (−1, 1). In fact, we prove by degeneration to a nodal P that an associated period map has derivative generically of full rank.
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