Cosmology of minimal varying Lambda theories

@article{Alexander2019CosmologyOM,
  title={Cosmology of minimal varying Lambda theories},
  author={Stephon H. S. Alexander and Marina Cort{\^e}s and Andrew R. Liddle and Jo{\~a}o Magueijo and Robert Sims and Lee Smolin},
  journal={Physical Review D},
  year={2019}
}
Inserting a varying Lambda in Einstein’s field equations can be made consistent with the Bianchi identities by allowing for torsion, without the need to add scalar field degrees of freedom. In the minimal such theory, Lambda is totally free and undetermined by the field equations in the absence of matter. Inclusion of matter ties Lambda algebraically to it, at least when homogeneity and isotropy are assumed, i.e., when there is no Weyl curvature. We show that Lambda is proportional to the… 

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