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

Abstract

We consider a cosmological model in a Friedmann--Lema\^{\i}tre--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.