Conformal Higgs Gravity (1712.02638v3)

Abstract: It is shown that gravitation naturally emerges from the standard model of particle physics if local scale invariance is imposed in the context of a single conformal (Weyl-symmetric) theory. Gravitation is then conformally-related to the standard model via a conformal transformation, merely a function of the number of fermionic particles dominating the energy density associated with the ground state of the physical system. Doing so resolves major puzzles afflicting the standard models of particle physics and cosmology, clearly indicating these to be artifacts stemming from universally employing the system of units selected here and now. In addition to the three known fundamental interactions mediated by gauge bosons, a scalar-tensor interaction is also accommodated by the theory; its inertial and gravitational sectors are characterized by whether contributions to the Weyl tensor vanish or are finite, respectively. In this approach both inertia and gravity are viewed as collective phenomena, with characteristic gravitational Planck scale devoid of fundamental meaning; consequently, mass hierarchy and Higgs mass instability concerns are avoided altogether. Only standard model particles gravitate; dark matter and dark energy have an inertial origin, and since the Higgs field does not interact with photons it is an ideal candidate for explaining the dark sector of cosmology. On cosmological scales the dynamical vacuum-like Higgs self-coupling accounts for dark energy, and its observed proximity at present to the energy density of nonrelativistic matter is merely a consistency requirement. Spatially varying vacuum expectation value of the Higgs field could likely account for the apparent cold dark matter on both galactic and cosmological scales.