The Operator Daugavet Property in Semifinite Noncommutative $L_1$-Spaces

Let $\mathcal M$ be a diffuse semifinite von Neumann algebra endowed with a faithful normal semifinite trace $τ$. We prove that, for every nonzero Banach space $Y$, the projective tensor product $L_1(\mathcal M,τ)\widehat{\otimes}_πY$ has the operator Daugavet property. Moreover, the witnessing oper