Abstract
Given two distinct newforms with real Fourier coefficients, we show that the set of primes where the Hecke eigenvalues of one of them dominate the Hecke eigenvalues of the other has density \(\ge \)1/16. Furthermore, if the two newforms do not have complex multiplication, and neither is a quadratic twist of the other, we also prove a similar result for the squares of their Hecke eigenvalues.
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Acknowledgements
The author thanks Farshid Hajir, Dinakar Ramakrishnan, and Siman Wong for helpful conversations, and also the anonymous referee for useful comments and suggestions.
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Chiriac, L. Comparing Hecke eigenvalues of newforms. Arch. Math. 109, 223–229 (2017). https://doi.org/10.1007/s00013-017-1072-x
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DOI: https://doi.org/10.1007/s00013-017-1072-x