Emergent dark matter in late time universe on holographic screen

Abstract

We discuss a scenario that the dark matter in late time universe emerges as part of the holographic stress-energy tensor on the hypersurface in higher dimensional flat spacetime. Firstly we construct a toy model with a de Sitter hypersurface as the holographic screen in the flat bulk. After adding the baryonic matter on the screen, we assume that both of the dark matter and dark energy can be described by the Brown-York stress-energy tensor. From the Hamiltonian constraint equation in the flat bulk, we find an interesting relation between the dark matter and baryonic matter's energy density parameters, by comparing with the Lambda cold dark matter parameterization. We further compare this holographic embedding of emergent dark matter with traditional braneworld scenario and present an alternative interpretation as the holographic universe. It can be reduced to our toy constraint in the late time universe, with the new parameterization of the Friedmann equation. We also comment on the possible connection with Verlinde's emergent gravity, where the dark matter is treated as the elastic response of the baryonic matter on the de Sitter spacetime background. We show that from the holographic de Sitter model with elasticity, the Tully-Fisher relation and the dark matter distribution in the galaxy scale can be derived.

Emergent dark universe and the swampland criteria

“…The effective cosmological constant in the future infinity turns out to be Λ = 3 L 2 [6]. The modified Friedmann equation becomes…”

“…Where Λ 0 = 3Ω Λ H 2 0 /c 2 is the effective cosmological constant at the future infinity [6] and it can be calculated from Ω Λ in Table 2. The linear term h 1 φ M P is dropped because we have V (φ)| φ→0 = 0.…”

“…One of the alternatives to the particle dark matter is the modified gravity [1,2], which can be applied to both the inflationary era and late time acceleration of the universe. Inspired by Verlinde's recent derivation on the emergent gravity [5], a holographic model of the Emergent Dark Universe (hEDU) has been proposed in [6], where the shortened name "hFRW" was also used. It assumes that the stress-energy tensor of the total dark components, including dark energy and apparent dark matter, is provided by the holographic fluid on the 3 + 1 dimensional Friedmann-Robertson-Walker (FRW) hypersurface, which is embedded in a 4 + 1 dimensional Minkowski bulk.…”

Galactic dynamics and long-range quantum gravity

“…However, this is correct only if one assumes that DE does not react to the presence of baryonic matter. The existence of such a DE reaction is quite natural in an emergent gravity [8] or corpuscular gravity [22,23,24,36,37,38] scenario and in view of our lack of understanding of DE represents the most plausible assumption. In this paper we will assume that this is the case.…”

“…Motivated by these considerations, recently, there have been some alternative proposal to explain the galactic-scale phenomenology commonly attributed to dark matter. For example, in one of these approaches the additional MOND acceleration is associated to a "dark force" (DF) generated by the reaction of dark energy (DE) to the presence of baryonic matter [8,22,23,36,37,38]. In an another approach, this is the result of an environmental modification of the inertial/gravitational mass ratio [39].…”