Zobrazeno 1 - 10
of 118
pro vyhledávání: '"Kofinas, Georgios"'
Publikováno v:
Int.J.Mod.Phys.D 28 (2019) 14, 1944013
The novel idea is that the undergoing accelerated expansion of the universe happens due to infrared quantum gravity modifications at intermediate astrophysical scales of galaxies or galaxy clusters, within the framework of Asymptotically Safe gravity
Externí odkaz:
http://arxiv.org/abs/2102.07578
Publikováno v:
Phys. Rev. D 103, 104025 (2021)
A new set of field equations for a space-time dependent Newton's constant $G(x)$ and cosmological constant $\Lambda(x)$ in the presence of matter is presented. We prove that it represents the most general mathematically consistent, physically plausib
Externí odkaz:
http://arxiv.org/abs/2012.05338
Autor:
Zarikas, Vasilios, Kofinas, Georgios
Publikováno v:
Journal of Physics: Conference Series, Volume 1051, XX International Meeting "Physical Interpretations of Relativity Theory 2017" 3-6 July 2017, Moscow, Russian Federation
Asymptotic Safety (AS) Program for quantum gravity keeps the same fields and symmetries with General Relativity and studies the associated gravitational action as a fundamental part of the complete theory at the nonperturbative level with the help of
Externí odkaz:
http://arxiv.org/abs/2006.08674
A recently proposed Asymptotically Safe cosmology provides an elegant mechanism towards understanding the nature of dark energy and its associated cosmic coincidence problem. The underlying idea is that the accelerated expansion of the universe can o
Externí odkaz:
http://arxiv.org/abs/1806.10580
Autor:
Kofinas, Georgios
Publikováno v:
Journal of Modern Physics 11 (2020) 1013-1030
Christoffel connection did not enter gravity as an axiom of minimal length for the free fall of particles (where anyway length action is not defined for massless particles), nor out of economy, but from the weak equivalence principle (gravitational f
Externí odkaz:
http://arxiv.org/abs/1712.02215
Autor:
Kofinas, Georgios, Zarikas, Vasilios
Publikováno v:
Phys. Rev. D 97, 123542 (2018)
A novel idea is proposed for a natural solution of the dark energy and its cosmic coincidence problem. The existence of local antigravity sources, associated with astrophysical matter configurations distributed throughout the universe, can lead to a
Externí odkaz:
http://arxiv.org/abs/1706.08779
Autor:
Kofinas, Georgios, Lima, Nelson A.
Publikováno v:
Phys. Rev. D 96, 084016 (2017)
In this work we focus on a novel completion of the well-known Brans-Dicke theory that introduces an interaction between the dark energy and dark matter sectors, known as complete Brans-Dicke (CBD) theory. We obtain viable cosmological accelerating so
Externí odkaz:
http://arxiv.org/abs/1704.08925
Autor:
Kofinas, Georgios, Zarikas, Vasilios
Publikováno v:
Phys. Rev. D 94, 103514 (2016)
General non-singular accelerating cosmological solutions for an initial cosmic period of pure vacuum birth era are derived. This vacuum era is described by a varying cosmological "constant" suggested by the Renormalisation Group flow of Asymptotic Sa
Externí odkaz:
http://arxiv.org/abs/1605.02241
We discuss the cosmological implications of an extended Brans-Dicke theory presented recently, in which there is an energy exchange between the scalar field and ordinary matter, determined by the theory. A new mass scale is generated in the theory wh
Externí odkaz:
http://arxiv.org/abs/1602.02687
Autor:
Kofinas, Georgios, Tsoukalas, Minas
Recently the most general completion of Brans-Dicke theory was appeared with energy exchanged between the scalar field and ordinary matter, given that the equation of motion for the scalar field keeps the simple wave form of Brans-Dicke. This class o
Externí odkaz:
http://arxiv.org/abs/1512.04786