Type: Article
Publication Date: 2014-01-01
Citations: 26
DOI: https://doi.org/10.4310/cjm.2014.v2.n1.a3
We show that there are primitive holomorphic modular forms f of weight two and arbitrary large level N such that $|f(z)| \gg N^{1/4}$ for some point z. Thereby we disprove a folklore conjecture that the sup-norm of such forms would be as small as $N^{o(1)}$.