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arXiv · 2403.17278

A unimodular Kaluza-Klein theory

Júlio C. Fabris·Richard Kerner
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Abstract

Unimodular gravity became an object of increasing interest in the late $80$-ties and was recently used in primordial Universe modeling with cosmological constant, in the context of the Brans-Dicke gravity including scalar field. In the present article we investigate the possibility of imposing the unimodular condition within the $5$-dimensional Kaluza-Klein theory including the scalar field. The variational principle is formulated in $5$ dimensions first, and dimensional reduction is applied to the resulting set of equations. A cosmological model based on these equations is then presented and discussed.

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Júlio C. Fabris, Richard Kerner. 2024-03-25. A unimodular Kaluza-Klein theory. https://arxiv.org/abs/2403.17278

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