The quantum character of the Scalar Field Dark Matter

Abstract

The Scalar Field Dark Matter (SFDM) model, also called Fuzzy, Wave, Bose-Einstein, Ultra-light Dark Matter, has received a lot of attention because it has been able to provide simpler and more natural explanations for various features of galaxies, such as the number of satellite galaxies and the cusp-core problem. We recently showed that this model is able to explain the vast polar orbits of satellite galaxies around their host, the so-called VPO, and to explain the X-ray and gamma-ray emissions in the vacuum regions of our galaxy, that is, the Fermi Bubbles. In all these phenomena the quantum character of SFDM has been crucial. In this work we study the quantum effects of SFDM at the cosmological level, to see these effects not only at the galactic scale, but also at the cosmological scale. Using a convenient ansatz, we were able to integrate the perturbed equations to show that the shape of the SFDM halos resembling atoms is a generic result. The main conclusion of this work is that quantum mechanics, the successful microworld theory, could also explain the dark side of the cosmos.

Short review of the main achievements of the scalar field, fuzzy, ultralight, wave, BEC dark matter model

“…where Y m l are the spherical harmonics functions, to explain these observations and show that this behavior of the satellites is very natural in SFDM. This is so because the quantum character of the SFDM (Matos, 2022) allows us to put the states of the SF as in an atom. The ground state is spherically symmetric, but the first excited state has a figure-8 shape, aligning surrounding objects with the figure-8 shape.…”

“…The other observation that can be explained using the SFDM in a very natural way is the VPOs. One of the main characteristics of the SFDM is its quantum character (Matos, 2022), even though the SF is considered classical in this model, the SF complies with the Schrödinger equation that contains excited states. This is a characteristic unique to this model, therefore, if we see more galaxies with VPO or with Femi bubbles, this will be a strong corroboration that SFDM or some very similar candidate is the final answer for the DM nature in the universe.…”

Proca stars with dark photons from spontaneous symmetry breaking of the scalar field dark matter

“…One of the most fascinating characteristics of SFDM is its quantum nature, recently studied in [14]. Due to this property, the SFDM model is capable of explaining phenomena such as the vast polar orbits of satellite galaxies around their host, the so-called VPO [15], observed in systems such as the Milky Way, Andromeda, and Cen A.…”

Constraints on the rotating self-dual black hole with quasi-periodic oscillations

“…The prevailing theory of gravity, known as general relativity (GR), has had remarkable success in describing the laws of gravity in our universe, e.g., the prediction of gravitational waves [1][2][3][4] and the Kerr spacetime for astrophysical black hole [5][6][7][8]. However, a few problems still remain unsolved, such as its incompatibility with quantum mechanics [9][10][11], as well as the existence of singularities where the known laws of physics do not apply, such as at the origin of the universe [12,13] and inside black holes [14]. To overcome these issues, various modified or quantum gravity theories have been proposed as possible replacements or extensions to GR.…”