Dark Energy: Illusion

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Dark Energy - Apr 1, 2012 at 6:50AM
yogesh chavan
1 Posts

The presence of high density stuffs like baryonic matter makes size of the Universe less than same calculated by considering the Universe filled uniformly with matter which density is equal to critical density. Hence, Hubble time or Observed cosmic time (for galaxies) is less than actual cosmic time which based upon critical density. As per General Theory of Relativity, matter slows down expansion of space (Time Dilation Effect) which further decreases Hubble time; while cosmic time for large empty space (voids) between galaxies (where gravity effect is negligible) become more than Hubble time but, less than actual cosmic time. There are lot of voids between distant galaxies and us adding more space-time. Cumulative effect of addition of this extra space-time affects cosmological observations of distant supernova giving illusion of accelerated expansion of the Universe. Because of voids, distant supernovas are supposed to be fainter than expected, but it doesn't mean that "Current Universe is accelerating". Large number of voids produces illusion effect of dark energy i.e. repulsive gravity effect.