Related papers: Solving the Cusp-Core Problem with a Novel Scalar …
We continue to study the spherically symmetric vacuum solutions of the tensor-four-scalars theory which is a modification of general relativity. Our aim is to construct vacuum solutions with asymptotically constant circular velocity curves…
Although the standard cosmological model, the so-called $\Lambda$ Cold Dark Matter ("$\Lambda$CDM"), appears to fit well observations at the cosmological level, it is well known that it possesses several inconsistencies at the galactic…
The distribution of dark matter in the inner regions of galaxies poses a key challenge for small-scale {\Lambda}CDM cosmology. While cold dark matter simulations predict cuspy inner density profiles, observations of low surface brightness…
We investigate static, spherically symmetric halo configurations within Unified Dark Matter (UDM) scalar-field models, developing a systematic mapping between standard cold dark matter (CDM) density profiles and their UDM counterparts.…
In this work we analyze and review cosmological models in which the dynamics of a single scalar field accounts for a unified description of the Dark Matter and Dark Energy sectors, dubbed Unified Dark Matter (UDM) models. In this framework,…
Low Surface Brightness (LSB) galaxies are dominated by dark matter. High-resolution rotation curves suggest that their total mass-density distributions are dominated by constant density cores rather than the steep and cuspy distributions…
The `core-cusp' problem is considered a key challenge to the LCDM paradigm. Halos in dark matter only simulations exhibit `cuspy' profiles, where density continuously increases towards the centre. However, the dark matter profiles of many…
The core-cusp problem is one of the controversial issues in the standard paradigm of $\Lambda$ cold dark matter ($\Lambda$CDM) theory. However, under the assumption of conventional spherical symmetry, the strong degeneracy among model…
Observations show that the underlying rotation curves at intermediate radii in spiral and low-surface brightness galaxies are nearly universal. Further, in these same galaxies, the product of the central density and the core radius…
We discuss scenarios in which the galactic dark matter in spiral galaxies is described by a long range coherent field which settles in a stationary configuration that might account for the features of the galactic rotation curves. The…
The observed rotation curves of dark matter-dominated dwarf galaxies indicate low density cores, contrary to the predictions of CDM models. A possible solution of this problem involves stellar feedback. A strong baryonic wind driven by…
In this paper we review the main and the most recent evidence for the presence of a core radius in the distribution of the dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an…
The core-cusp problem is a widely cited motivation for the exploration of dark matter models beyond standard CDM. One such alternative is ULDM; extremely light scalar particles exhibiting wavelike properties on kiloparsec scales.…
An exact scalar field cosmological model is constructed from the exact solution of the field equations. The solutions are exact and no approximation like slow roll is used. The model gives inflation, solves horizon and flatness problems.…
We consider the problem of determining the structure of the dark halo of nearby dwarf spheroidal galaxies (dSphs) from the spherical Jeans equations. Whether the dark halos are cusped or cored at the centre is an important strategic problem…
The concordance cosmological model based on cold dark matter makes definitive predictions for the growth of galaxies in the Universe, which are being actively studied using numerical simulations. These predictions appear to contradict the…
The cold dark matter (CDM) cosmological model has been remarkably successful in explaining cosmic structure over an enormous span of redshift, but it has faced persistent challenges from observations that probe the innermost regions of dark…
The core-cusp problem persists as an unresolved tension between the predictions of $\Lambda$CDM cosmology and observations of dark matter (DM) profiles in dwarf spheroidal and other galaxies. We present a novel scenario for converting cusps…
Dark matter (DM) can consist of a scalar field so light that DM particles in the galactic halo are best described by classical waves. We investigate how these classical solutions are influenced by the presence of a non-rotating supermassive…
The presence of a dark matter core in the central kiloparsec of many dwarf galaxies has been a long standing problem in galaxy formation theories based on the standard cold dark matter paradigm. Recent cosmological simulations, based on…