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arXiv · 2111.09966

Freezing of Gauge Symmetries in the Heterotic String on $T^4$

Bernardo Fraiman·Héctor Parra de Freitas
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Abstract

We derive a map relating the gauge symmetry groups of heterotic strings on $T^4$ to other components of the moduli space with rank reduction. This generalizes the results for $T^2$ and $T^3$ which mirror the singularity freezing mechanism of K3 surfaces in F and M-theory, respectively. The novel feature in six dimensions is that the map explicitly involves the topology of the gauge groups, in particular acting only on non-simply-connected ones. This relation is equivalent to that of connected components of the moduli space of flat $G$-bundles over $T^2$ with $G$ non-simply-connected. These results are verified with a reasonably exhaustive list of gauge groups obtained with a moduli space exploration algorithm.

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Bernardo Fraiman, Héctor Parra de Freitas. 2021-11-18. Freezing of Gauge Symmetries in the Heterotic String on $T^4$. https://doi.org/10.1007/jhep04(2022)007

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