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We revise the cosmological standard model presuming that matter, i.e. baryonsand cold dark matter, exhibits a non-vanishing pressure mimicking thecosmological constant effects. In particular, we propose a scalar fieldLagrangian $\mathcal L_1$ for matter with the introduction of a Lagrangemultiplier as constraint. We also add a symmetry breaking effective potentialaccounting for the classical cosmological constant problem, by adding a secondLagrangian $\mathcal{L}_2$. Investigating the Noether current due to the shiftsymmetry on the scalar field, $\varphi\rightarrow\varphi+c^0$, we show that$\mathcal{L}_1$ turns out to be independent from the scalar field $\varphi$.Further we find that a positive Helmotz free-energy naturally leads to anegative pressure without introducing by hand any dark energy term. To face outthe fine-tuning problem, we investigate two phases: before and after transitiondue to the symmetry breaking. We propose that during transition dark mattercancels out the quantum field vacuum energy effects. This process leads to anegative and constant pressure whose magnitude is determined by baryons only.The numerical bounds over the pressure and matter densities are in agreementwith current observations, alleviating the coincidence problem. Finallyassuming a thermal equilibrium between the bath and our effective fluid, weestimate the mass of the dark matter candidate. Our numerical outcomes seem tobe compatible with recent predictions on WIMP masses, for fixed spin andtemperature. In particular, we predict possible candidates whose masses span inthe range $0.5-1.7$ TeV.

Speeding up the universe using dust with pressure