For a century, Albert Einstein's theory of general relativity has been the cornerstone of our understanding of gravity, asserting its influence across not just three physical dimensions but also time.

"This model of gravity has been essential for everything from theorizing the Big Bang to photographing black holes," stated Robin Wen, the project's lead author and a recent graduate in Mathematical Physics from Waterloo.

"However, at the scale of galaxy clusters and beyond, we notice discrepancies with the predictions of general relativity. It appears that gravity does not align perfectly with Einstein's formulation, showing about a one per cent deviation at distances spanning billions of light years," Wen explained.

Efforts to address these discrepancies have been ongoing for over two decades, especially at Waterloo, known for its pioneering research in gravity through collaborations between applied mathematicians and astrophysicists.

"Almost a century ago, astronomers discovered that our universe is expanding," noted Niayesh Afshordi, a professor of astrophysics at Waterloo and a researcher at the Perimeter Institute.

"The farther away galaxies are, the faster they appear to move, approaching the speed of light, which is the maximum speed allowed by Einstein's theory. Our findings suggest that at these vast distances, Einstein's theory might also be inadequate," Afshordi added.

The team's new model tweaks Einstein's mathematical framework to account for these cosmological anomalies without undermining the successful applications of general relativity.

"Consider it a footnote to Einstein's theory, where additional terms and conditions apply once you engage with cosmic scales," Wen remarked.

"This new model could represent the initial piece of a cosmic puzzle that we are just beginning to piece together across the expanses of space and time," Afshordi concluded.

Research Report:A cosmic glitch in gravity

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