Speeding up the Universe using dust with pressure

  title={Speeding up the Universe using dust with pressure},
  author={Orlando Luongo and Marco Muccino},
  journal={Physical Review D},
We revise the cosmological standard model presuming that matter, i.e., baryons and cold dark matter, exhibits a nonvanishing pressure mimicking the cosmological constant effects. In particular, we propose a scalar field Lagrangian ${\mathcal{L}}_{1}$ for matter with the introduction of a Lagrange multiplier as constraint. We also add a symmetry breaking effective potential accounting for the classical cosmological constant problem, by adding a second Lagrangian ${\mathcal{L}}_{2… 

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