English

Landau-Siegel Zeros of Triple Product L-functions

Number Theory 2026-01-09 v3

Abstract

Let FF be a number field. Let π1,π2\pi_1,\pi_2 be cuspidal automorphic representations of GL2(AF)GL_2(\mathbb{A}_F), and let π\pi be a cuspidal automorphic representation of either GL2(AF)GL_2(\mathbb{A}_F) or GL3(AF)GL_3(\mathbb{A}_F). When (π1,π2,π)(\pi_1,\pi_2,\pi) is of general type, we show that the triple product LL-function L(s,π1×π2×π)L(s,\pi_1 \times \pi_2 \times \pi) on either GL(2)×GL(2)×GL(2)GL(2) \times GL(2) \times GL(2) or GL(2)×GL(2)×GL(3)GL(2) \times GL(2) \times GL(3) has a standard zero-free region with no exceptional Landau-Siegel zero. Moreover, when (π1,π2,π)(\pi_1,\pi_2,\pi) is not of general type, we give precise conditions when L(s,π1×π2×π)L(s,\pi_1 \times \pi_2 \times \pi) could possibly have exceptional Landau-Siegel zeros.

Keywords

Cite

@article{arxiv.2508.06423,
  title  = {Landau-Siegel Zeros of Triple Product L-functions},
  author = {Shifan Zhao},
  journal= {arXiv preprint arXiv:2508.06423},
  year   = {2026}
}

Comments

21 pages. This preprint is now superseded by arXiv:2601.04189