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In this work we suggest a simple model of the cosmological constant as the coefficient of the quantum tunneling of vacuum fluctuations (with wave length larger than Planck length) at tiny, boundary spherical shell of the universe (with thickness equivalent to Planck length and radius equivalent to scale factor). Roughly speaking, given fluctuations can, by quantum tunneling (i.e. scattering with a potential barrier with highness equivalent to Planck energy and width proportional to, approximately, three hundred Planck length) leave universe and arrive in its exterior, i.e. multi-universe (in sense of Linde chaotic inflation theory universe can be considered as a causally-luminally connected space domain while its exterior can be considered as a space domain without causal-luminal connections with universe). It is in full agreement with usual quantum mechanics and quantum field theory as well as WMAP observational data (especially fine tuning condition).
Theoretically, the running of the cosmological constant in the IR region is not ruled out. On the other hand, from the QFT viewpoint, the energy released due to the variation of the cosmological constant in the late universe cannot go to the matter s
Deriving the Einstein field equations (EFE) with matter fluid from the action principle is not straightforward, because mass conservation must be added as an additional constraint to make rest-frame mass density variable in reaction to metric variati
We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements $sqrt{-{g}}d^{4}x$ and $Phi d^{4}x$, where $Phi $ is a metric independent density, also curvature
The cosmological constant $Lambda$ is usually interpreted as Dark Energy (DE) or modified gravity (MG). Here we propose instead that $Lambda$ corresponds to a boundary term in the action of classical General Relativity. The action is zero for a perfe
The standard electroweak theory of leptons and the conformal groups of spacetime Weyls transformations are at the core of a general relativistic, conformally covariant scalar tensor theory aimed at the resolution of the most intriguing enigma of mode