A widely publicized report that cosmic microwave background, the glow left over from the explosive start of the universe believed to have occurred 13.7 billion years ago, contains echoes of previous cycles of cosmic birth and death, has been disputed by new analyses.

Three teams state that circular patterns do exist but are entirely consistent with the leading model for the birth of the universe, known as inflation, and do not require an alternative, pre–Big Bang theory. According to inflation, the universe began as a subatomic entity that ballooned in size during the first tiny fraction of a second of its existence.

ScienceNews has the full story and the arXiv papers are:

A search for concentric circles in the 7-year WMAP temperature sky maps by I. K. Wehus and H. K. Eriksen

No evidence for anomalously low variance circles on the sky by Adam Moss, Douglas Scott, James P. Zibin

Are There Echoes From The Pre-Big Bang Universe? A Search for Low Variance Circles in the CMB Sky by Amir Hajian