Joint Number Theory Seminar

Modular curves X_1(n) as moduli of point arrangements

Time and Location:

Dec. 05, 2024 at 5:30PM; Warren Weaver Hall, Room 512

Speaker:

Lev Borisov, Rutgers University

Abstract:

For a complex elliptic curve E and a point p of order n on it, the images of the points pk = kp under the Weierstrass embedding of E into CP2 are collinear if and only if the sum of indices is divisible by n. We prove that for n at least 10 a collection of n points in P2 with these properties comes (generically) from a point of order n on an elliptic curve. In the process, we discover amusing identities between logarithmic derivatives of the theta function at rational points. I will also discuss potential applications of these results to bounds on the numbers of Hecke eigenforms for Γ1(n) of positive analytic rank, although this is rather speculative. This is joint work with Xavier Roulleau, 

see: https://arxiv.org/pdf/2404.04364.

Notes:

There will be Tea 5:00pm