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arXiv · 1812.06457

Scalar field as a null dust

Valerio Faraoni·Jeremy Côté
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Abstract

We show that a canonical, minimally coupled scalar field which is non-self interacting and massless is equivalent to a null dust fluid (whether it is a test or a gravitating field), in a spacetime region in which its gradient is null. Under similar conditions, the gravitating and nonminimally coupled Brans-Dicke-like scalar of scalar-tensor gravity, instead, cannot be represented as a null dust unless its gradient is also a Killing vector field.

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Valerio Faraoni, Jeremy Côté. 2018-12-16. Scalar field as a null dust. https://doi.org/10.1140/epjc%2Fs10052-019-6829-x

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