Modular forms with large coefficient fields via congruences
© Dieulefait et al.; licensee Springer. 2015
Received: 8 October 2014
Accepted: 16 December 2014
Published: 29 May 2015
We use the theory of congruences between modular forms to prove the existence of newforms with square-free level having a fixed number of prime factors such that the degree of their coefficient fields is arbitrarily large. We also prove a similar result for certain almost square-free levels.