ASKSAGE: Sage Q&A Forum - Individual question feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Tue, 18 Aug 2020 00:55:32 -0500The modular tower of curves over a finite field.https://ask.sagemath.org/question/53092/the-modular-tower-of-curves-over-a-finite-field/I want to investigate the tower of modular curves $X(\ell^n) \to X(1)$ over a finite field $\mathbb F_q$ with $\ell \neq 0 0 \in \mathbb F_q$ and pullbacks of this tower by maps $C \to X(1)$.
In particular, I want to investigate the characteristic polynomial of the Frobenius on the $\ell$-adic cohomology. If I knew defining equations for $X(n)$ in terms of the parameter $t$ on $X(1)$, I guess I could do it but I am not sure... Tue, 18 Aug 2020 00:55:32 -0500https://ask.sagemath.org/question/53092/the-modular-tower-of-curves-over-a-finite-field/