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arXiv · 1308.4798

Multi-field G-inflation

Tsutomu Kobayashi·Norihiro Tanahashi·Masahide Yamaguchi
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Abstract

We propose a multi-field extension of (generalized) G-inflation, based on covariant multi-galileons and their generalization preserving second-order field equations. We compute the quadratic action for cosmological perturbations. By comparing the formulas for cosmological perturbations, it is highlighted that multi-field DBI galileon inflation is not included in the multi-field version of generalized G-inflation. Our result indicates that the generalized covariant multi-galileon theory is not the most general multi-scalar-tensor theory with second-order field equations.

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Tsutomu Kobayashi, Norihiro Tanahashi, Masahide Yamaguchi. 2013-10-03. Multi-field G-inflation. https://doi.org/10.1103/physrevd.88.083504

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