Moments of zeta functions associated to hyperelliptic curves
Moments of zeta functions associated to hyperelliptic curves
I will discuss conjectures, theorems, and experiments concerning the moments, at the central point, of zeta functions associated to hyperelliptic curves over finite fields of odd characteristic. Let q be an odd prime power, and Hd,q denote the set of square-free monic polynomials D(x)∈Fq[x] of degree d. Let 2g=d−1 if d is odd, and 2g=d−2 if d is even. Katz and Sarnak showed that the moments (over Hd,q) of the zeta functions associated to the curves y2=D(x), evaluated at the central point, tend, as q→∞, to the moments of characteristic polynomials of matrices in USp(2g), evaluated at the central point. Using techniques that were originally developed for studying moments of L-functions over number fields, Andrade and Keating have conjectured an asymptotic formula for the moments for q fixed and d→∞. We provide theoretical and numerical evidence in favour of their conjecture. We will also discuss uniform estimates, in both parameters q,d, for the moments. This is joint work with Kevin Wu.