Skip to main content

Timeline for Modular forms on $\Gamma(N)$

Current License: CC BY-SA 4.0

10 events
when toggle format what by license comment
Mar 31, 2021 at 16:26 comment added Peter Humphries Yes, that's correct.
Mar 31, 2021 at 14:24 comment added xir @PeterHumphries I managed to find it in Miyake, I guess you meant z/N and not z/q, right?
Mar 31, 2021 at 14:23 comment added xir @FrançoisBrunault thanks, that's very helpful!
Mar 30, 2021 at 19:25 comment added Kimball Did you try Cohen-Stromberg or Miyake? Those are fairly thorough treatments of modular forms, and they probably at least explain Peter's comment. (Diamond-Shurman probably explains Peter's comment as well.)
Mar 30, 2021 at 18:40 comment added Gerald Edgar Also see LMFDB lmfdb.org
Mar 30, 2021 at 18:38 comment added François Brunault In his PhD thesis, Weinstein has computed the decomposition of $S_k(\Gamma(N))$ as a $\mathrm{SL}_2(\mathbb{Z}/N\mathbb{Z})$-module. math.bu.edu/people/jsweinst/jswthesis.pdf
Mar 30, 2021 at 18:17 comment added François Brunault If you adopt the automorphic language, then by Casselman's theorem, for any irreducible smooth representation of $\mathrm{GL}_2(\mathbb{Q}_p)$, the new vector will be on $\Gamma_1(p^r)$ for some $r$. See arxiv.org/abs/1008.2796
Mar 30, 2021 at 18:04 history edited xir CC BY-SA 4.0
added 1 character in body
Mar 30, 2021 at 17:35 comment added Peter Humphries I don't think this kind of thing is written down anywhere. The key point is that $$\mathcal{M}_k(\Gamma(N)) = \bigoplus_{\chi \pmod{N}} \mathcal{M}_k(\Gamma_0(N^2),\chi).$$ More precisely, given $f \in \mathcal{M}_k(\Gamma_0(N^2),\chi)$, the function $g(z) = f(z/q)$ is an element of $\mathcal{M}_k(\Gamma(N))$, and every element arises in this way (up to taking appropriate linear combinations). So all of the key properties of $\Gamma(N)$ can be reduced to properties for $\Gamma_0(N)$ and $\Gamma_1(N)$.
Mar 30, 2021 at 17:22 history asked xir CC BY-SA 4.0