The abnormally weighting energy hypothesis: the missing link between dark matter and dark energy

Abstract

Abstract. We generalize tensor-scalar theories of gravitation by the introduction of an abnormally weighting type of energy. This theory of tensor-scalar anomalous gravity is based on a relaxation of the weak equivalence principle that is now restricted to ordinary visible matter only. As a consequence, the convergence mechanism toward general relativity is modified and produces naturally cosmic acceleration as an inescapable gravitational feedback induced by the mass-variation of some invisible sector. The cosmological implications of this new theoretical framework are studied. From the Hubble diagram cosmological test alone, this theory provides an estimation of the amount of baryons and dark matter in the Universe that is consistent with the independent cosmological tests of Cosmic Microwave Background (CMB) and Big Bang Nucleosynthesis (BBN). Cosmic coincidence is naturally achieved from a equally natural assumption on the amplitude of the scalar coupling strength. Finally, from the adequacy to supernovae data, we derive a new intriguing relation between the spacetime dependences of the gravitational coupling and the dark matter mass, providing an example of crucial constraint on microphysics from cosmology. This glimpses at an enticing new symmetry between the visible and invisible sectors, namely that the scalar charges of visible and invisible matter are exactly opposite.

Elliptic solutions of generalized Brans–Dicke gravity with a non-universal coupling

“…We start by considering the action in the Jordan frame of the generalized Brans-Dicke theory introduced in [20,21] …”

“…First, in [51] it was proved that the target space M = (R 3 , h) with the metric (34) is a homogeneous space isomorphic to the coset space G/H , where G is the isometry group of M and H is the isotropy subgroup of G. Thus, in this case one can find solutions to the geodesic equations (20). Second, it was shown in [21] that cosmic acceleration in the Jordan frame requires an inverse proportionality of A m and A a . It should be noted that the exponential coupling functions give us a target space with constant curvature R = 2k 2 m (see Appendix A).…”

“…[20,21] the AWE hypothesis within the framework of the generalized Brans-Dicke theory with a nonuniversal coupling was proposed. The original motivation for studying this type of models is related to a unified description of dark matter (DM) and dark energy (DE) based on a relaxation of the weak equivalence principle on large scales [22][23][24][25].…”

“…In [21] the cosmological evolution was studied in a flat FLRW background using a fluid description for the matter and the AWE sectors.…”

Dark Matter and Dark Energy from Gravitational Symmetry Breaking

“…This effect is small, since it is related to high-order loop corrections, but it could be detected in future experiments aiming at verifying universality of free fall for ordinary matter particles with very high accuracy. The second effect on usual particles due to the abundance of mass-varying DM is an induced violation of the strong equivalence principle (SEP), introduced by Alimi & Füzfa [11]. The SEP is an extension of the WEP to gravitational binding energies, yielding that gravitation is produced in the same way by any kind of energy, including gravitational ones.…”