After the Big Bang, our universe began to expand at an exponential rate, an acceleration scientists have long attributed to a mysterious force known as dark energy. This idea—which earned its discoverers the Nobel Prize in 2011—has largely defined our understanding of cosmic growth for decades. But new research is starting to challenge this long-held assumption.

A team of researchers has uncovered new evidence suggesting that the universe may already be slowing down, rather than continuing to speed up. The analysis, published November 5 in Monthly Notices of the Royal Astronomical Society , puts a damper on leading theories that suggest dark energy is driving the universe’s continued acceleration.

As the findings oppose the prevailing view, the paper will likely face harsh scrutiny

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