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arXiv · 1705.04604

From an Action Principle for Action-dependent Lagrangians toward non-conservative Gravity: accelerating Universe without dark energy

Matheus J. Lazo·Juilson Paiva·João T. S. Amaral·Gastão S. F. Frederico
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Abstract

In the present work, we propose an Action Principle for Action-dependent Lagrangians by generalizing the Herglotz variational problem for several independent variables. This Action Principle enables us to formulate Lagrangian densities for non-conservative fields. In special, from a Lagrangian depending linearly on the Action, we obtain a generalized Einstein's field equations for a non-conservative gravity and analyze some consequences of their solutions to cosmology and gravitational waves. We show that the non-conservative part of the field equations depends on a constant cosmological four-vector. Depending on this four-vector, the theory displays damped/amplified gravitational waves and an accelerating Universe without dark energy.

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Matheus J. Lazo, Juilson Paiva, João T. S. Amaral, Gastão S. F. Frederico. 2017-05-12. From an Action Principle for Action-dependent Lagrangians toward non-conservative Gravity: accelerating Universe without dark energy. https://doi.org/10.1103/physrevd.95.101501

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