The Generalized Riemann Hypothesis from zeros of a single L-function

Abstract: For each primitive Dirichlet character $\chi$, a hypothesis ${\rm GRH}^\dagger[\chi]$ is formulated in terms of zeros of the associated $L$-function $L(s,\chi)$. It is shown that for any such character, ${\rm GRH}^\dagger[\chi]$ is equivalent to the Generalized Riemann Hypothesis.