Zobrazeno 1 - 10
of 995
pro vyhledávání: '"H. Mohseni"'
Autor:
H. Mohseni Sadjadi
Publikováno v:
Physics Letters B, Vol 857, Iss , Pp 138967- (2024)
We present a model in which the Gauss-Bonnet invariant holds the quintessence at a fixed point, respecting an initial Z2 symmetry in the radiation-dominated era. This results in an early dark energy that becomes significant around the matter-radiatio
Externí odkaz:
https://doaj.org/article/285f8fe83c7940b0aab07c2019a12b14
Publikováno v:
Physics Letters B, Vol 850, Iss , Pp 138493- (2024)
A modified version of the MSW effect is studied within the framework of screening models through conformal couplings of a scalar field within matter. Such a coupling leads to a new, unknown interaction between the scalar field and the neutrino. We ma
Externí odkaz:
https://doaj.org/article/c872cdb1e5a248b79126e7aada1d5bf0
Autor:
H. Mohseni Sadjadi
Publikováno v:
Physics Letters B, Vol 850, Iss , Pp 138508- (2024)
We introduce a dynamical dark energy model wherein quintessence interacts with both the Gauss-Bonnet invariant and dark matter. Initially, the Gauss-Bonnet invariant stabilizes the quintessence at a fixed point, resulting in a negligible density of d
Externí odkaz:
https://doaj.org/article/483ab278c7584c93baf9ee9512a2c7e9
Autor:
Parviz Goodarzi, H. Mohseni Sadjadi
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 79, Iss 3, Pp 1-9 (2019)
Abstract We study the cosmological inflation and reheating in a teleparallel model of gravity. Reheating is assumed to be due to the decay of a scalar field to radiation during its rapid oscillation. By using cosmological perturbations during inflati
Externí odkaz:
https://doaj.org/article/dd636800ba2140fc9c9c60bc67319e38
Autor:
Sadjadi, H. Mohseni
Publikováno v:
Phys. Lett. B 857,138967(2024)
We present a model in which the Gauss-Bonnet invariant holds the quintessence at a fixed point, respecting an initial $Z_2$ symmetry in the radiation-dominated era. This results in an early dark energy that becomes significant around the matter-radia
Externí odkaz:
http://arxiv.org/abs/2404.19695
Autor:
H. Mohseni Sadjadi, M. Khodaei
Publikováno v:
Physics Letters B, Vol 799, Iss , Pp - (2019)
We investigate the existence of scalar hair in the background of a reflecting star. The kinetic part of the scalar field is nonminimally coupled to the Einstein tensor. For both the Dirichlet and the Neumann boundary conditions, we study the no-hair
Externí odkaz:
https://doaj.org/article/84512ae4a30f4063946088262a0f306a
Autor:
Parviz Goodarzi, H. Mohseni Sadjadi
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 77, Iss 7, Pp 1-12 (2017)
Abstract In the cold inflation scenario, the slow roll inflation and reheating via coherent rapid oscillation, are usually considered as two distinct eras. When the slow roll ends, a rapid oscillation phase begins and the inflaton decays to relativis
Externí odkaz:
https://doaj.org/article/2b824908c73d4fec82321d36c6c3dcb7
Autor:
H. Mohseni Sadjadi
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 77, Iss 3, Pp 1-8 (2017)
Abstract We study the parameterized post-Newtonian approximation in teleparallel model of gravity with a scalar field. The scalar field is non-minimally coupled to the scalar torsion as well as to the boundary term introduced in Bahamonde and Wright
Externí odkaz:
https://doaj.org/article/a960c5a3d7d64dc093e3dcfc474be6a5
Autor:
M. Khodaei, H. Mohseni Sadjadi
Publikováno v:
Physics Letters B, Vol 797, Iss , Pp - (2019)
We investigate the existence of the skyrmion field in the background of an asymptotically flat stationary reflecting star. For this purpose, we consider the Einstein-Skyrme system for which there is a skyrmion hair in the black hole case. We discuss
Externí odkaz:
https://doaj.org/article/dce644254be14f1e8a4d4afa48054657
Autor:
Sadjadi, H. Mohseni
We consider a model consisting of a quintessence coupled to the Ricci scalar and the Gauss-Bonnet invariant. We propose a mechanism for the rising of dark energy in the matter era, alleviating the coincidence problem. The role of the Gauss-Bonnet inv
Externí odkaz:
http://arxiv.org/abs/2310.03697