Non-vanishing of twists of $\text{GL}_4(\mathbb{A}_{\mathbb{Q}})$ $L$-functions

Abstract: Let $\pi$ be a unitary cuspidal automorphic representation of $\text{GL}{4}(\mathbb{A}{\mathbb{Q}})$. Let $f \geq 1$ be given. We show that there exists infinitely many primitive even (resp. odd) Dirichlet characters $\chi$ with conductor co-prime to $f$ such that $L(s, \pi \otimes \chi)$ is non-vanishing at the central point. Our result has applications for the construction of $p$-adic $L$-functions for $\text{GSp}{4}$ following Loeffler-Pilloni-Skinner-Zerbes, the Bloch-Kato conjecture and the Birch-Swinnerton-Dyer conjecture for abelian surfaces following Loeffler-Zerbes, strong multiplicity one results for paramodular cuspidal representations of $\text{GSp}{4}(\mathbb{A}{\mathbb{Q}})$ and the rationality of the central values of $\text{GSp}{4}(\mathbb{A}_{\mathbb{Q}})$ $L$-functions in the remaining non-regular weight case.