New Scalar Field Quartessence

Abstract

We propose a cosmological scenario involving a scalar field, $\phi$, that is a source of Dark Matter as well as of Dark Energy. Besides $\phi$, the Lagrangian of the field theory envisaged in our scenario contains a second field $\chi$, for simplicity assumed to be a scalar, too. For fixed values of $\chi$, the potential term decays exponentially at large positive values of $\phi$. While $\phi$ is not coupled to Standard Model fields, $\chi$ is assumed to be coupled to them, and the Green functions of $\chi$ depend on the cosmological redshift in the expanding universe. We assume that the term in the Lagrangian coupling $\chi$ to $\phi$ is such that, at redshifts $z$ larger than some critical redshift $z_c$, $\phi$ is trapped near $\phi =0$, and oscillations of $\phi$ about $\phi =0$ describing massive scalar particles give rise to Dark Matter. At redshifts below $z_c$, the field $\phi$ is no longer trapped near the origin and starts to `roll' towards large field values. A homogenous component of $\phi$ emerges that acts as Dark Energy. Within over-dense regions, such as galaxies and galaxy clusters, the redshifting of $\chi$ stops, and $\phi$ therefore remains trapped near $\phi =0$ as long as $z_c$ is smaller than the redshift when structures on galactic scales decouple from the Hubble flow. Thus, at the present time, $\phi$ describes both Dark Energy and Dark Matter.

6 pages

References in corpus (8)

• Cosmology and the Fate of Dilatation Symmetry
• Dark Energy and the Accelerating Universe
• Ultralight scalars as cosmological dark matter
• On the Geometry of the String Landscape and the Swampland
• An Alternative to Particle Dark Matter
• Unified Dark Matter Scalar Field Models
• Chiral Gravitational Waves and Baryon Superfluid Dark Matter
• Analytic Study of Cosmological Perturbations in a Unified Model of Dark Matter and Dark Energy with a Sharp Transition

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• Dark D-Brane Cosmology: from background evolution to cosmological perturbations
• Constraints on dark energy models from the Horndeski theory
• Inflation, Swampland, and Landscape
• Dynamics of DiskMass Survey galaxies in refracted gravity
• Unified Dark Matter, Dark Energy and Baryogenesis via a "Cosmological Wetting Transition''
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• Unified dark fluid with null sound speed as an alternative to phantom dark energy
• Dark Coincidences: Small-Scale Solutions with Refracted Gravity and MOND
• A Kaluza-Klein Inspired Brans-Dicke Gravity with Dark Matter and Dark Energy Model
• Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the string-theoretical Swampland Programme
• After the Dark Ages