Mimetic Weyl geometric gravity
Abstract
We consider a mimetic type extension of the Weyl geometric gravity theory, by assuming that the metric of the space-time manifold can be parameterized in terms of a scalar field, called the mimetic field. Within the framework of the mimetic field, it is possible to provide a geometrical explanation for Dark Matter and late-time acceleration. Initially, we formulate the conformally invariant gravitational action with a new degree of freedom - the Weyl vector, where we include the effective matter action and the mimetic field via the Lagrangian multiplier formulation. The field equations are obtained from the variational principle; this is accomplished by varying the action with respect to the metric tensor, the Weyl vector, the scalar field and the Lagrange multiplier. Linearization of the gravitational action is achieved through the integration of an auxiliary term, the scalar field. In the present paper, the cosmological evolution of the mimetic Weyl theory is explored for an isotropic and homogeneous FLRW (Friedmann–Lemaitre–Robertson–Walker) universe, by obtaining the Friedmann equations of the standard general relativity. Finally, we discuss some cosmological applications, and we compare the results of the theory with a standard model.
- Publication:
-
7th International Conference in Astronomy
- Pub Date:
- July 2023
- Bibcode:
- 2023aasp.confE..12V