Abstract
In 1980, Gross conjectured a formula for the expected leading term at $s=0$ of the Deligne–Ribet $p$-adic $L$-function associated to a totally even character $\psi $ of a totally real field $F$. The conjecture states that after scaling by $L(\psi \omega ^{-1}, 0)$, this value is equal to a $p$-adic regulator of units in the abelian extension of $F$ cut out by $\psi \omega ^{-1}$. In this paper, we prove Gross’s conjecture.