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Abstract

Given a finite $\mathbb{Z}_2$-graded group $\hat{\mathsf{G}}$ with ungraded
subgroup $\mathsf{G}$ and a twisted cocycle $\hat{\lambda} \in Z^n(B
\hat{\mathsf{G}}; \mathsf{U}(1)_{\pi})$ which restricts to $\lambda \in Z^n(B
\mathsf{G}; \mathsf{U}(1))$, we construct a lift of $\lambda$-twisted $\mathsf{G}$-Dijkgraaf--Witten theory to an unoriented topological quantum field theory. Our construction uses a new class of homotopy field theories, which we call orientation twisted. We also introduce an orientation twisted variant of the orbifold procedure, which produces an unoriented topological field theory from an orientation twisted $\mathsf{G}$-equivariant topological field theory.