By K.S. Jayraman 

Bengaluru, Oct 30 (IANS): Indian astrophysicist Abhas Mitra, whose revolutionary theories challenging the existence of "black holes" and "dark matter" remain uncontested till date, again feels vindicated.

Mitra is former head of theoretical astrophysics at the Bhabha Atomic Research Centre and now adjunct professor at the Homi Bhabha National Institute in Mumbai.

He says the prediction he made four years ago that the universe may not be undergoing accelerated expansion -- contradicting the view of mainstream cosmologists -- has now found support from an independent study reported by physicists from Oxford University.

Under the prevailing cosmological model, the universe created after the Big Bang is not just expanding, but the expansion is actually accelerating -- a discovery for which the Nobel Prize in Physics was given to three astronomers in 2011.

This discovery was based on an analysis of "red shift" or unexpected "dimness" of light from supernovae -- the stunning thermonuclear explosion of dying stars -- picked up by the Hubble space telescope and large ground-based telescopes.

This reported "red shift" was attributed to the existence of a mysterious substance named 'dark energy' and led to widespread acceptance of the idea that the universe is dominated by this "Dark Energy", driving its expansion with acceleration.

But in a series of peer reviewed publications since 2012, Mitra had shown that there is no dark energy at all and "must be an artifact for explaining a complex inhomogeneous universe by an oversimplified Big Bang model".

In his publications Mitra had shown that because there is no dark energy, there can be no acceleration of the universe. "But nobody listened to my exact theoretical results questioning the existence of the dark energy," Mitra told this correspondent.

That situation seems to have now changed with the publication of a new, more detailed, study by Oxford University researchers in "Scientific Reports", a sister publication of the reputed journal Nature.

The Oxford team, led by Subir Sarkar, has also cast doubt on the standard cosmological concept of accelerating expansion of the universe, lending strong support to Mitra's prediction.

The researchers analyzed the emissions from a staggering 740 supernovae and concluded that the evidence for an accelerating universe is "flimsy". They have admitted that their work "serves to demonstrate that a key pillar of the standard cosmological model is rather shaky".

While claiming that the study by Oxford scientists has supported his theory about a non-accelerating universe, Mitra said his studies call for a paradigm shift from the Big Bang models that require the existence of dark matter that has not yet been detected.