Time variable $\Lambda$ and the accelerating Universe

Abstract

We perform a deductive study of accelerating Universe and focus on the importance of variable time-dependent $\Lambda$ in the Einstein's field equations under the phenomenological assumption, $\Lambda =\alpha H^2$ for the full physical range of $\alpha$. The relevance of variable $\Lambda$ with regard to various key issues like dark matter, dark energy, geometry of the field, age of the Universe, deceleration parameter and barotropic equation of state has been trivially addressed. The deceleration parameter and the barotropic equation of state parameter obey a straight line relationship for a flat Universe described by Friedmann and Raychaudhuri equations. Both the parameters are found identical for $\alpha =1$.

Latex, 10 pages, 2 figures, accepted in IJTP

References in corpus (14)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set
• The $\nu$MSM, Dark Matter and Baryon Asymmetry of the Universe
• The $\nu$MSM, Dark Matter and Neutrino Masses
• Realistic sterile neutrino dark matter with keV mass does not contradict cosmological bounds
• Cosmographic Hubble fits to the supernova data
• Dark Matter and Baryons in the Most X-ray Luminous and Merging Galaxy Cluster RX J1347.5-1145
• The dark energy equation of state
• Catching a bullet: direct evidence for the existence of dark matter
• Multiple Lambda cosmology: dark fluid with time-dependent equation of state as classical analog of cosmological landscape
• Neutrino masses, leptogenesis and dark matter in hybrid seesaw
• Dark Energy Fluid with Time-Dependent, Inhomogeneous Equation of State
• Dark Energy Models With Variable Equation Of State Parameter
• Scenario of inflationary cosmology from the phenomenological $\Lambda$ models

Cited by in corpus (7)

• Variable Equation of State for Generalized Dark Energy Model
• Cosmological model with linear equation of state parameter in f(R, Lm) gravity
• Variable cosmological term $\Lambda (t)$
• Generalized phenomenological models of dark energy
• Cosmological volume acceleration in dust epoch: using scaling solutions and variable cosmological term $\Lambda (t)$ within an anisotropic cosmological model
• Accelerating Universe from Modified Kasner Model in Extra Dimensions
• Modified Power law Inflation: solution to the graceful exit problem and improvement of dark energy models