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arXiv · 1808.10605

Kaluza-Klein reduction on a maximally non-Riemannian space is moduli-free

Kyoungho Cho·Kevin Morand·Jeong-Hyuck Park
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Abstract

We propose a novel Kaluza-Klein scheme which assumes the internal space to be maximally non-Riemannian, meaning that no Riemannian metric can be defined for any subspace. Its description is only possible through Double Field Theory but not within supergravity. We spell out the corresponding Scherk-Schwarz twistable Kaluza--Klein ansatz, and point out that the internal space prevents rigidly any graviscalar moduli. Plugging the same ansatz into higher-dimensional pure Double Field Theory and also to a known doubled-yet-gauged string action, we recover heterotic supergravity as well as heterotic worldsheet action. In this way, we show that 1) supergravity and Yang-Mills theory can be unified into higher-dimensional pure Double Field Theory, free of moduli, and 2) heterotic string theory may have a higher-dimensional non-Riemannian origin.

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Kyoungho Cho, Kevin Morand, Jeong-Hyuck Park. 2019-04-16. Kaluza-Klein reduction on a maximally non-Riemannian space is moduli-free. https://doi.org/10.1016/j.physletb.2019.04.042

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