Is the universe gently twirling? Scientists say the universe could be completing one rotation in nearly 500 billion years

The universe is a place of mind-bending mysteries and vast, ancient expanse that is still not fully understood. Our cosmos never ceases to surprise us, be it the Big Bang, black holes, dark matter, or the accelerating expansion of space. There have been decades of research and advanced technologies like the James Webb Space Telescope, which have been constantly researching this, but still, the astronomers have some fundamental questions about the universe’s structure and behaviour remaining in their bag.
Now, a new study from the University of Hawai‘i Institute for Astronomy has probably brought us one step closer to resolving some unknown mysteries about the universe.
In a study published in the Monthly Notices of the Royal Astronomical Society, astrophysicist István Szapudi and his team suggest that the universe could be slowly rotating, completing one full revolution roughly every 500 billion years. That is very slow and too subtle for current instruments to directly detect, but it could be enough to change the way space behaves on a cosmic scale.
The idea comes from a simple observation that everything in the universe spins. Planets, stars, galaxies, and even black holes all rotate.
So why not the universe itself?
“To paraphrase the Greek philosopher Heraclitus of Ephesus, who famously said, ‘Panta Rhei’, which means that everything moves, we thought that perhaps Panta Kykloutai – everything turns,” said Szapudi, lead author of the study, as quoted by the University of Hawai‘i news release.

The Hubble tension is a long-standing difference between two different ways of measuring the universe's expansion rate. One method is through using nearby supernovae and galaxies, which gives a higher value than another method that looks at cosmic microwave background radiation from the early universe. These conflicting numbers have confused scientists and led some to suggest that entirely new physics may be needed.
But Szapudi’s team created a mathematical model that includes a small amount of cosmic rotation, without breaking any known laws of physics. “Much to our surprise, we found that our model with rotation resolves the paradox without contradicting current astronomical measurements,” Szapudi said.

What makes this model particularly suitable is that it doesn’t require new theories or particles. It fits within standard physics by also offering a novel explanation for a decades-old cosmic puzzle.
"It is compatible with other models that assume rotation. Therefore, perhaps, everything really does turn. Or, Panta Kykloutai!” Szapudi added.
If this rotating universe theory holds up under further studies, it could be quite a progress in how we understand the cosmos.