Zobrazeno 1 - 10
of 10
pro vyhledávání: '"Shankar Dayal Pathak"'
Publikováno v:
Physical Sciences Forum, Vol 7, Iss 1, p 49 (2023)
We investigate the background dynamics of a class of models with noncanonical scalar field and matter both in Friedmann Lemaitre Robertson Walker (FLRW) closed and open spacetime. The detailed dynamical system analysis is carried out in a bouncing sc
Externí odkaz:
https://doaj.org/article/867497dea1ec46e09fcc91c7b9393297
We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark energy. We obtained the functional form of scale factor by assuming that the coupling strength depends linearly on the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5dffa8a0ae7dbe33a0ec71c80eee6a9f
http://arxiv.org/abs/2006.14928
http://arxiv.org/abs/2006.14928
Publikováno v:
Journal of Physics: Conference Series. 1531:012086
It is an accepted and well examined practice in cosmology to invoke a suitable form of scalar field with potential V(φ) when the observed evolution of the universe cannot be reconciled with theoretical believes. In this article we investigate the ro
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::70a5625702180e890efb152d4a698418
https://doi.org/10.1088/1742-6596/1531/1/012086
https://doi.org/10.1088/1742-6596/1531/1/012086
Publikováno v:
Chinese Physics C. 44:023105
Dark sector may couple to the Standard Model via one or more mediator particles. We discuss two types of mediators: the dark photon $A^{\prime}$ and the dark scalar mediator $\phi$. The total cross-sections and various differential distributions of t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::eaf62585ef6d1dad23d0c465c021e349
https://doi.org/10.1088/1674-1137/44/2/023105
https://doi.org/10.1088/1674-1137/44/2/023105
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 77, Iss 10, Pp 1-12 (2017)
European Physical Journal
European Physical Journal
In this paper, we apply the dynamical analysis to a coupled phantom field with scaling potential taking particular forms of the coupling (linear and combination of linear), and present phase space analysis. We investigate if there exist late time acc
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0c687101ba4de5286b2bf2fe0e93cbe1
https://doi.org/10.1140/epjc/s10052-017-5255-1
https://doi.org/10.1140/epjc/s10052-017-5255-1
Publikováno v:
Astrophysics and Space Science. 350:381-384
We discuss the expansion of the universe in the FRLW model assuming that the source of dark energy is either tachyonic scalar field or quintessence. The tachyonic scalar field with exponential and power-law potential (function of homogeneous scalar f
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::81855cf051e429a6857e121e68f3580a
https://doi.org/10.1007/s10509-013-1736-3
https://doi.org/10.1007/s10509-013-1736-3
Publikováno v:
Astrophysics and Space Science. 344:505-512
We propose a model of the evolution of the tachyonic scalar field over two phases in the universe. The field components do not interact in phase I, while in the subsequent phase II, they change flavours due to relative suppression of the radiation co
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::88e360e130319b0342f080b9f4af576e
https://doi.org/10.1007/s10509-012-1348-3
https://doi.org/10.1007/s10509-012-1348-3
Publikováno v:
European Physical Journal C
In this paper, we investigate coupled quintessence with scaling potential assuming specific forms of the coupling as $A$ namely, $\alpha \dot{\rho_m}$, $\beta \dot{\rho_{\phi}}$ and $\sigma (\dot{\rho_m}+\dot{\rho_{\phi}})$, and present phase space a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::394d99ab6aed6547254dd446dc50920d
http://arxiv.org/abs/1503.08712
http://arxiv.org/abs/1503.08712
Publikováno v:
International Journal of Modern Physics D. 23:1450075
It is proposed that the recently announced BICEP2 value of tensor-to-scalar ratio r ~ 0.2 can be explained as containing an extra contribution from the recent acceleration of the universe. In fact this contribution, being robust, recent and of much l
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f33c4fe1bf9c085ab02a9050ea8c14b6
https://doi.org/10.1142/s0218271814500758
https://doi.org/10.1142/s0218271814500758
Publikováno v:
Journal of Physics: Conference Series. 481:012015
We propose a model with thermodynamic origin of interaction among the components of tachyonic scalar field in the universe. The components are taken to exist in the state of non-equilibrium initially but undergoing a transition towards the equilibriu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::551e9912057111fb0d61644a5e622cff
https://doi.org/10.1088/1742-6596/481/1/012015
https://doi.org/10.1088/1742-6596/481/1/012015