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arXiv · 2505.15207

Canonical Structure and Hidden Symmetries in Scalar Field Cosmology

Andronikos Paliathanasis
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Abstract

We investigate hidden symmetries in minimally coupled scalar field cosmology within the FLRW universe, and a perfect fluid with and without interaction to the scalar field. We show that for an exponential potential there exists a set of canonical transformations through which the cosmological field equations can be recast in the form of a free particle in flat space. Based on this equivalence, we construct a mapping that generates cosmological solutions with interaction terms, corresponding to a chameleon mechanism. Finally, we discuss how this class of canonical transformations can relate the solution spaces of different cosmological models, such as of the scalar field and of the $\Lambda$-Cosmology.

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Andronikos Paliathanasis. 2025-05-21. Canonical Structure and Hidden Symmetries in Scalar Field Cosmology. https://doi.org/10.1088/1361-6382%2Fae29dc

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