# Time-dependent G in Einstein’s equations as an alternative to the cosmological constant

@article{Hanmeli2019TimedependentG, title={Time-dependent G in Einstein’s equations as an alternative to the cosmological constant}, author={Ekim Taylan Hanımeli and Brahim Lamine and Alain Blanchard and Isaac Tutusaus}, journal={Physical Review D}, year={2019} }

In this work we investigate cosmologies where the gravitational constant varies in time, with the aim of explaining the accelerated expansion without a cosmological constant. We achieve this by considering a phenomenological extension to general relativity, modifying Einstein's field equations such that $G$ is a function of time, $G(t)$, and we preserve the geometrical consistency (Bianchi identity) together with the usual conservation of energy by introducing a new tensor field to the…

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