Zobrazeno 1 - 10
of 50
pro vyhledávání: '"Sukanta Panda"'
Autor:
Abhijith Ajith, Sukanta Panda
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 83, Iss 8, Pp 1-12 (2023)
Abstract We study an inflation model driven by a triplet of antisymmetric tensor fields, with minimal and nonminimal couplings to gravity. First, we show that the presence of a triplet of antisymmetric tensor fields can provide inherent background is
Externí odkaz:
https://doaj.org/article/cfd5f2a1ab704a398173b3d1fdb0032f
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 83, Iss 4, Pp 1-12 (2023)
Abstract In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field $$\phi $$ ϕ with Ricci scalar R in a general form of $$f(R,\phi )$
Externí odkaz:
https://doaj.org/article/26fbef97100c412285fb0c3e68e093df
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 83, Iss 2, Pp 1-17 (2023)
Abstract The strange behaviour of the universe’s dark sector offers us the flexibility to address cosmological problems with different approaches. Using this flexibility, we consider a possible exchange of energy among the dark sector components as
Externí odkaz:
https://doaj.org/article/e556b465725943ab8aee0121a0940e32
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 10, Pp 1-10 (2022)
Abstract In this paper, we aim to investigate the effects of the anisotropy on the scale-invariant power spectrum considering the matter-dominated collapsing universe as background and look for the deviations from the scale invariance. Having set up
Externí odkaz:
https://doaj.org/article/bdb5faaa463f48209693423476290fc9
Autor:
Pawan Joshi, Sukanta Panda
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 7, Pp 1-12 (2022)
Abstract We construct a Hamiltonian for the nonlocal F(R) theory in the present work. By this construction, we demonstrate the nature of the ghost degrees of freedom. Finally, we find conditions that give rise to ghost-free theories.
Externí odkaz:
https://doaj.org/article/418233c0902047d4a7230c0f6546b6b2
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 7, Pp 1-7 (2020)
Abstract The strong gravitational field near massive blackhole is an interesting regime to test General Relativity (GR) and modified gravity theories. The knowledge of spacetime metric around a blackhole is a primary step for such tests. Solving fiel
Externí odkaz:
https://doaj.org/article/45f49b306dea4ab58c07c92c18af0f4b
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 79, Iss 9, Pp 1-6 (2019)
Abstract Models of inflation with antisymmetric tensor studied in the past are plagued with ghost instability even in an unperturbed FRW background. We show that it is possible to avoid ghosts in an unperturbed FRW background by considering the most
Externí odkaz:
https://doaj.org/article/96916a57e14c444aaedc0429bfbecd36
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 78, Iss 11, Pp 1-8 (2018)
Abstract We investigate the possibility of inflation with models of antisymmetric tensor field having minimal and nonminimal couplings to gravity. Although the minimal model does not support inflation, the nonminimal models, through the introduction
Externí odkaz:
https://doaj.org/article/e3c717d880c24c11af3ba641127d013f
Publikováno v:
European Physical Journal
In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field $\phi$ with Ricci scalar $R$ in a general form of $f(R,\phi)$. Using Palatin
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::09b87bbc0527b34b819f41cc28806ae8
http://repo.scoap3.org/api
http://repo.scoap3.org/api
Autor:
Sukanta Panda, Pawan Joshi
Publikováno v:
Springer Proceedings in Physics ISBN: 9789813344075
Higher order derivative theories, generally suffer from instabilities, known as Ostrogradsky instabilities. This issue can be resolved by removing any existing degeneracy present in such theories. We consider a model involving at most second-order de
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::507adeba7f28978b37e6a700b0bb3d52
https://doi.org/10.1007/978-981-33-4408-2_128
https://doi.org/10.1007/978-981-33-4408-2_128
