# A Lagrangian description of interacting dark energy

@article{Popawski2006ALD, title={A Lagrangian description of interacting dark energy}, author={Nikodem J. Popławski}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2006} }

We propose a relativistically covariant model of interacting dark energy based on the principle of least action. The cosmological term $\Lambda$ in the gravitational Lagrangian is a function of the trace of the energy--momentum tensor $T$. We find that the $\Lambda(T)$ gravity is more general than the Palatini $f(R)$ gravity, and reduces to the latter if we neglect the pressure of matter. We show that recent cosmological data favor a variable cosmological constant and are consistent with the…

## 48 Citations

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