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We construct a two dimensional unoriented open/closed topological field theory from a finite graded group $$\pi:\Gh \twoheadrightarrow \{1,-1\}$$, a $$\pi$$-twisted $$2$$-cocycle $$\hat{\theta}$$ on $$B \hat{G}$$ and a character $$\lambda: \hat{G} \rightarrow U(1)$$. The underlying oriented theory is a twisted Dijkgraaf--Witten theory. The construction is based on a detailed study of the $$(\hat{G}, \hat{\theta},\lambda)$$-twisted Real representation theory of $$\textnormal{ker} \pi$$. In particular, twisted Real representations are boundary conditions of the unoriented theory and the generalized Frobenius--Schur element is its crosscap state.
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Combinatoric topological string theories and group theory algorithms
A bstract A number of finite algorithms for constructing representation theoretic data from group multiplications in a finite group G have recently been shown to be related to amplitudes for combinatoric topological strings ( G -CTST) based on Dijkgraaf-Witten theory of flat G -bundles on surfaces. We extend this result to projective representations of G using twisted Dijkgraaf-Witten theory. New algorithms for characters are described, based on handle creation operators and minimal multiplicative generating subspaces for the centers of group algebras and twisted group algebras. Such minimal generating subspaces are of interest in connection with information theoretic aspects of the AdS/CFT correspondence. For the untwisted case, we describe the integrality properties of certain character sums and character power sums which follow from these constructive G -CTST algorithms. These integer sums appear as residues of singularities in G -CTST generating functions. S -duality of the combinatoric topological strings motivates the definition of an inverse handle creation operator in the centers of group algebras and twisted group algebras.
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- Award ID(s):
- 2014086
- PAR ID:
- 10438706
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2022
- Issue:
- 10
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/JHEP10(2022)147
