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arXiv · 2004.14863

Scalar field emulator via anisotropically deformed vacuum energy: Application to dark energy

Ozgur Akarsu·Nihan Katirci·Anjan A. Sen·J. Alberto Vazquez
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Abstract

We introduce a generalization of the usual vacuum energy, called `deformed vacuum energy', which yields anisotropic pressure whilst preserving zero inertial mass density. It couples to the shear scalar in a unique way, such that they together emulate the canonical scalar field with an arbitrary potential. This opens up a new avenue by reconsidering cosmologies based on canonical scalar fields, along with a bonus that the kinetic term of the scalar field is replaced by an observable, the shear scalar. We further elaborate the aspects of this approach in the context of dark energy.

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Ozgur Akarsu, Nihan Katirci, Anjan A. Sen, J. Alberto Vazquez. 2020-04-29. Scalar field emulator via anisotropically deformed vacuum energy: Application to dark energy. https://arxiv.org/abs/2004.14863

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