Proceedings Paper for REU Project Involving Counting Eta-Quotients
It is known that all modular forms on $SL_2(Z)$ can be expressed as a rational function in $η(z)$, $η(2z)$ and $η(4z)$. By using a theorem by Gordon, Hughes, and Newman, and calculating the order of vanishing, we can compute the $η$-quotients for a given level. Using this count, knowing how many $η$-quotients are linearly independent and using the dimension formula, we can figure out how the $η$-quotients span higher levels. In this paper, we primarily focus on the case where $N=p$ a prime, and some discussion for non-prime indicies.