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Higher-Dimensional Geometric Sigma Models

M. Vasilić
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Abstract

Geometric $σ$-models have been defined as purely geometric theories of scalar fields coupled to gravity. By construction, these theories possess arbitrarily chosen vacuum solutions. Using this fact, one can build a Kaluza--Klein geometric $σ$-model by specifying the vacuum metric of the form $M^4\times B^d$. The obtained higher dimensional theory has vanishing cosmological constant but fails to give massless gauge fields after the dimensional reduction. In this paper, a modified geometric $σ$-model is suggested, which solves the above problem.

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M. Vasilić. 1998-07-11. Higher-Dimensional Geometric Sigma Models. https://doi.org/10.1103/physrevd.60.025003

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