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arXiv · 1308.1469

Further refinement of strong multiplicity one for GL(2)

Nahid Walji
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Abstract

We obtain a sharp refinement of the strong multiplicity one theorem for the case of unitary non-dihedral cuspidal automorphic representations for GL(2). Given two unitary cuspidal automorphic representations for GL(2) that are not twist-equivalent, we also find sharp lower bounds for the number of places where the Hecke eigenvalues are not equal, for both the general and non-dihedral cases. We then construct examples to demonstrate that these results are sharp.

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Nahid Walji. 2013-08-07. Further refinement of strong multiplicity one for GL(2). https://arxiv.org/abs/1308.1469

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