On Induction for Twisted Representations of Conformal Nets

Abstract

For a given finite index inclusion of conformal nets $\mathcal{B}\subset \mathcal{A}$ and a group $G<\mathrm{Aut}(\mathcal{A},\mathcal{B})$, we consider the induction and the restriction procedures for $G$-twisted representations. We define two induction procedures for $G$-twisted representations, which generalize the ${\alpha }^{\pm }$-induction for DHR endomorphisms. One is defined with the opposite braiding on the category of $G$-twisted representations as in ${\alpha }^{-}$-induction. The other is also defined with the braiding, but additionally with the $G$-equivariant structure on the Q-system associated with $\mathcal{B}\subset \mathcal{A}$ and the action of $G$. We derive some properties and formulas for these induced endomorphisms in a similar way to the case of ordinary $\alpha$-induction. We also show the version of $\alpha \sigma$-reciprocity formula for our setting.