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arXiv · 2208.02599

New exact and analytic solutions in Weyl Integrable cosmology from Noether symmetry analysis

Andronikos Paliathanasis
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Abstract

We consider a cosmological model in a Friedmann--Lema\^ıtre--Robertson--Walker background space with an ideal gas defined in Weyl Integrable gravity. In the Einstein-Weyl theory a scalar field is introduced in a geometric way. Furthermore, the scalar field and the ideal gas interact in the gravitational Action Integral. Furthermore, we introduce a potential term for the scalar field potential and we show that the field equations admit a minisuperspace description. Noether's theorem is applied for the constraint of the potential function and the corresponding conservation laws are constructed. Finally, we solve the Hamilton-Jacobi equation for the cosmological model and we derive a family of new solutions in Weyl Integrable cosmology. Some closed-form expressions for the Hubble function are presented.

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Andronikos Paliathanasis. 2022-08-04. New exact and analytic solutions in Weyl Integrable cosmology from Noether symmetry analysis. https://doi.org/10.1088/1402-4896%2Fac8702

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