On effaceability of certain $\delta$-functors

Abstract

We prove a conjecture of the first author for $G{L}_2(F)$, where $F$ is a finite extension of $Q_p$.

In the previous version we worked over a field and with a fixed central character. In this version we allow the coefficients to be artinian rings and do not fix a central character. The paper has been completely rewritten, but the main idea remained the same