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arXiv · 2211.02515

Discrete mean estimates and the Landau-Siegel zero

Yitang Zhang
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Abstract

Let $\chi$ be a real primitive character to the modulus $D$. It is proved that $$ L(1,\chi)\gg (\log D)^{-2022} $$ where the implied constant is absolute and effectively computable. In the proof, the lower bound for $L(1,\chi)$ is first related to the distribution of zeros of a family of Dirichlet $L$-functions in a certain region, and some results on the gaps between consecutive zeros are derived. Then, by evaluating certain discrete means of the large sieve type, a contradiction can be obtained if $L(1,\chi)$ is too small.

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Yitang Zhang. 2022-11-04. Discrete mean estimates and the Landau-Siegel zero. https://arxiv.org/abs/2211.02515

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