Permutation Orientifolds of Gepner Models

TL;DR

This paper constructs and analyzes permutation orientifolds in Gepner models, exploring their properties such as supersymmetry, charges, and gauge groups, advancing understanding of orientifold constructions in string theory.

Contribution

It develops a general method to construct permutation orientifolds in rational CFTs and applies it specifically to Gepner models, detailing their physical characteristics.

Findings

Constructed crosscap states for permutation orientifolds in rational CFTs.

Analyzed supersymmetry, tension, and RR charges of these orientifolds.

Determined gauge groups and tadpole cancellation conditions.

Abstract

In tensor products of a left-right symmetric CFT, one can define permutation orientifolds by combining orientation reversal with involutive permutation symmetries. We construct the corresponding crosscap states in general rational CFTs and their orbifolds, and study in detail those in products of affine U(1)_2 models or N=2 minimal models. The results are used to construct permutation orientifolds of Gepner models. We list the permutation orientifolds in a few simple Gepner models, and study some of their physical properties - supersymmetry, tension and RR charges. We also study the action of corresponding parity on D-branes, and determine the gauge group on a stack of parity-invariant D-branes. Tadpole cancellation condition and some of its solutions are also presented.