Dark Matter and Dark Energy Induced by Condensates

Abstract

It is shown that the vacuum condensate induced by many phenomena behaves as a perfect fluid which, under particular conditions, has zero or negative pressure. In particular, the condensates of thermal states, of fields in curved space and of mixed particles have been analyzed. It is shown that the thermal states with the cosmic microwave radiation temperature, the Unruh and the Hawking radiations give negligible contributions to the critical energy density of the universe, while the thermal vacuum of the intercluster medium could contribute to the dark matter, together with the vacuum energy of fields in curved space-time and of mixed neutrinos. Moreover, a component of the dark energy can be represented by the vacuum of axion-like particles mixed with photons and superpartners of neutrinos. The formal analogy among the systems characterized by the condensates can open new scenarios in the possibility to detect the dark components of the universe in table top experiments.PACS numbers:

Cosmological Effects of Quantum Vacuum Condensates

“…Such a condensate has a behavior completely different with respect to the ones of the condensates mentioned above. Indeed its state equation is w = −1, which is the one of the cosmological constant and the value of the vacuum energy density is compatible with the one inferred from the observations for dark energy, 10 −47 GeV 4 [40]. The results here presented establish a link between cosmology, particle physics and quantum field theory.…”

“…By computing the expectation values of Equation (1) for the (0, 0) and (j, j) components, one finds the explicit expressions of the energy density and of the pressure. For bosons, in the case of the isotropy of the momenta, ρ B , p B and the state equation w B = p B /ρ B are [40] …”

“…The kinematical terms of the energy density and pressure of fermion mixed fields are zero when averaged on |0(ξ, t) B , then one has [40] …”

“…In this paper, we report the recent results [40] showing that the vacuum condensate structure of many phenomena, such as particle mixing and fields in curved space [41][42][43][44][45][46][47][48][49][50][51][52][53][54], generates non trivial contributions to the energy of the universe [40], which can represent new components of dark energy and dark matter. In particular, dark matter components can be provided by the thermal vacuum of the hot plasma present at the center of a galaxy cluster, by the vacuum of fields in curved space [55] and by the flavor neutrino vacuum.…”

Kinetic theory of Jean instability in Eddington-inspired Born–Infeld gravity

“…Specifically, almost ∼68% of the total amount of the matter and energy in the Universe should be in form of the cosmological constant, or more in general of dark energy, a e-mail: ivan.demartino@ehu.eus b e-mail: capolupo@sa.infn.it while ∼26% should be in the form of invisible and exotic particles, named dark matter. Nevertheless their fundamental nature is still unknown [1][2][3][4]. The need to incorporate them has been interpreted as a breakdown of GR at astrophysical and cosmological scales, opening the door to alternative theories of gravity.…”