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arXiv · 1405.3938

Disformal invariance of second order scalar-tensor theories

Dario Bettoni
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Abstract

The Horndeski action is the most general one involving a metric and a scalar field that leads to second-order field equations in four dimensions. Being the natural extension of the well-known scalar-tensor theories, its structure and properties are worth analyzing along the experience accumulated in the latter context. Here, we argue that disformal transformations play, for the Horndeski theory, a similar role to that of conformal transformations for scalar-tensor theories a la Brans-Dicke.

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Dario Bettoni. 2014-05-12. Disformal invariance of second order scalar-tensor theories. https://arxiv.org/abs/1405.3938

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