Zobrazeno 1 - 10
of 72
pro vyhledávání: '"R. F. L. Holanda"'
The Hubble constant from galaxy cluster scaling-relation and SNe Ia observations: a consistency test
Autor:
Kamal Bora, R. F. L. Holanda
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 83, Iss 4, Pp 1-8 (2023)
Abstract In this paper, we propose a self-consistent test for a Hubble constant estimate using galaxy cluster and type Ia supernovae (SNe Ia) observations. The approach consists, in a first step, of obtaining the observational value of the galaxy clu
Externí odkaz:
https://doaj.org/article/cc50f3b41c074be6afc5ec3f540db8f4
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 6, Pp 1-10 (2022)
Abstract In this work, we discuss a new method to probe the redshift evolution of the gas depletion factor, i.e. the ratio by which the gas mass fraction of galaxy clusters is depleted with respect to the universal mean of baryon fraction. The datase
Externí odkaz:
https://doaj.org/article/a265ab3db7e948e39b5a0e1b671602fb
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 4, Pp 1-9 (2022)
Abstract A cosmological model in an Einstein–Cartan framework endowed with torsion is studied. For a torsion function assumed to be proportional to Hubble expansion function, namely $$\phi =-\alpha H$$ ϕ = - α H , the contribution of torsion func
Externí odkaz:
https://doaj.org/article/e5cbf69a376f493fb75e29633b5b825c
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 2, Pp 1-7 (2022)
Abstract In this paper, we use large scale structure observations to test the redshift dependence of cosmic distance duality relation (CDDR), $$D_\mathrm{L}(1+z)^{-2}/D_\mathrm{A}=\eta (z)$$ D L ( 1 + z ) - 2 / D A = η ( z ) , with $$D_\mathrm{L}$$
Externí odkaz:
https://doaj.org/article/a3d3bf6560a644fe9a0090701059a4e1
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 1, Pp 1-6 (2022)
Abstract In this paper, we implement a test of the standard law for the dark matter density evolution as a function of redshift. For this purpose, only a flat universe and the validity of the FRW metric are assumed. A deformed dark matter density evo
Externí odkaz:
https://doaj.org/article/e0b58fa07d7944ab93a01b280fac7a70
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 9, Pp 1-9 (2021)
Abstract In order to probe a possible time variation of the fine-structure constant ( $$\alpha $$ α ), we propose a new method based on Strong Gravitational Lensing and Type Ia Supernovae observations. By considering a class of runaway dilaton model
Externí odkaz:
https://doaj.org/article/2454927dd67d4d989674c44a18333291
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 7, Pp 1-7 (2021)
Abstract We propose a new method to explore a possible departure from the standard time evolution law for the dark matter density. We looked for a violation of this law by using a deformed evolution law, given by $$\rho _c(z) \propto (1+z)^{3+\epsilo
Externí odkaz:
https://doaj.org/article/6f234757802840aa955a6bf71eab03f7
Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 6, Pp 1-9 (2021)
Abstract A new method based on large scale structure observations is proposed to probe a possible temporal variation of the fine-structure constant ( $$\alpha $$ α ). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia S
Externí odkaz:
https://doaj.org/article/60bfbc0d520e43f299d71ce3def515d1
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 79, Iss 11, Pp 1-9 (2019)
Abstract A Friedmann like cosmological model in Einstein–Cartan framework is studied when the torsion function is assumed to be proportional to a single $$\phi (t)$$ ϕ(t) function coming just from the spin vector contribution of ordinary matter. B
Externí odkaz:
https://doaj.org/article/88baedef4d1d45f599a6cc9d4e5cdb4d
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 515:5981-5992
The Co-varying Physical Couplings (CPC) framework is a modified gravity set up assuming Einstein Field Equations wherein the quantities $\{G,c,\Lambda\}$ are promoted to space-time functions. Bianchi identity and the requirement of stress-energy tens
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2033e4e9d2c8ed001b861beeb228105e
https://doi.org/10.1093/mnras/stac2039
https://doi.org/10.1093/mnras/stac2039