Results 121 to 130 of about 143,913 (244)

FLRW model coupled with mass less scalar field in f(T) gravity-Two fluid scenario

East European Journal of Physics
In this work, we investigate a cosmological model within the framework of modified teleparallel gravity, known as f(T) gravity, by considering a spatially flat Friedmann-Lemaître-Robertson-Walker (FLRW) Universe filled with two fluids-barotropic matter ...
Vilas B. Raut, Sanjay A. Salve
doaj   +1 more source

Static State of a Black Hole Supported by Dark Matter

Universe, 2019
The possibility of an equilibrium state of a gravitating scalar field (describing ordinary matter) inside a black hole, compressed to the state of boson condensate, in balance with a longitudinal vector field (describing dark matter) from the outside, is
Boris E. Meierovich
doaj   +1 more source

Interacting scalar fields: Dark matter and early dark energy

Physical Review D
The main aim of this work is to explore the possibility that cold dark matter (CDM) and early dark energy (EDE) can be described by canonical scalar fields that are coupled at the level of its conservation equations. The formalism covers dynamical aspects at the background and linear perturbation levels for an arbitrary coupling function, followed by ...
Gabriela Garcia-Arroyo, L. Arturo Ureña-López, J. Alberto Vázquez   +2 more
openaire   +2 more sources

Scalar field dark matter and pulsar timing observations

, 2016
An ultralight free scalar field with mass around 10−23−10−22 eV is a viable dark mater candidate, which can help to resolve some of the issues of the cold dark matter on sub-galactic scales.
A. Khmelnitsky, V. Rubakov
semanticscholar   +1 more source

Dark Matter Decaying into a Fermi Sea of Neutrinos

, 2010
We study the possible decay of a coherently oscillating scalar field, interpreted as dark matter, into light fermions. Specifically, we consider a scalar field with sub-eV mass decaying into a Fermi sea of neutrinos.
Bjaelde, Ole Eggers, Das, Subinoy
core   +1 more source

Simple cosmological model with inflation and late times acceleration

European Physical Journal C: Particles and Fields, 2018
In the framework of polynomial Palatini cosmology, we investigate a simple cosmological homogeneous and isotropic model with matter in the Einstein frame.
Marek Szydłowski, Aleksander Stachowski
doaj   +1 more source

Scalar Fields in Cosmology: Inflation, Dark Matter, Dark Energy

, 2018
During the 12 years of project C6 of the SFB 676 it has achieved a set of significant contributions to our understanding of the dynamics of scalar fields in early universe cosmology and its connection to string theory. In this contribution we describe our results at this interface between theoretical cosmology and fundamental high-energy theory in ...
Louis, Jan, Westphal, Alexander
openaire   +2 more sources

vs. as a probe of a scalar mediator dark-matter scenario

Europhysics letters
Recently, Belle II reported the observation of the decay , where M X is the missing mass, with the branching ratio much exceeding which is the only Standard Model (SM) process contributing to this reaction.
A. Berezhnoy, D. Melikhov
semanticscholar   +1 more source

Ultraviolet running constraints on low mass dark sectors

Journal of High Energy Physics
We analyze the UV breakdown of Sub-GeV dark matter models that live in a new, dark U(1) sector. Many of these models include a scalar field, which is either the dark matter itself or a dark Higgs field that generates mass terms for the dark matter ...
Aidan Reilly, Natalia Toro
doaj   +1 more source

Acoustic misalignment mechanism for axion dark matter

Journal of High Energy Physics
A rotation in the field space of a complex scalar field corresponds to a Bose-Einstein condensation of U(1) charges. We point out that fluctuations in this rotating condensate exhibit sound-wave modes, which can be excited by cosmic perturbations and ...
Arushi Bodas, Raymond T. Co, Akshay Ghalsasi, Keisuke Harigaya, Lian-Tao Wang   +4 more
doaj   +1 more source