Could the entire universe be slowly spinning?
A new study suggests it might—and this gentle cosmic twist could help explain one of astronomy’s biggest puzzles.
The idea comes from a team of researchers, including István Szapudi from the University of Hawaiʻi at Mānoa.
They’ve proposed that the universe may be rotating extremely slowly, so slowly that we haven’t been able to detect it.
But even this barely noticeable spin might be enough to fix a long-standing problem known as the “Hubble tension.”
The Hubble tension is a mystery that has puzzled scientists for years. It’s all about how fast the universe is expanding. When astronomers measure this speed in two different ways, they get two different answers.
One method uses exploding stars called supernovae to track expansion over the last few billion years.
The other relies on ancient light left over from the Big Bang, which tells us about the universe’s expansion more than 13 billion years ago. The results from each method don’t match, and no one has been sure why.
Szapudi’s team wanted to see if adding a tiny twist to the usual model of the universe might help. Their mathematical model started off with the standard physics, assuming the universe expands evenly in all directions.
But then they added a slow rotation to the model—just enough to make a difference but still small enough that it wouldn’t have shown up in past observations.
To their surprise, the results worked. The model with rotation solved the Hubble tension and still agreed with current astronomical measurements.
Even better, it matched other scientific ideas that suggest the universe could have some kind of spin.
According to their calculations, the universe might rotate once every 500 billion years. That’s so slow we’d never notice it directly, but over time, it could subtly influence how the universe expands.
The researchers were inspired by an ancient idea from Greek philosopher Heraclitus, who said, “everything moves.” Szapudi updated that idea to say, “everything turns”—panta kykloutai in Greek.
This spinning-universe idea doesn’t break any known laws of physics. It might even help bring different parts of cosmology together in a more complete picture.
The next step is to build a full computer model and look for clues in the sky that could reveal whether the universe really does have a slow, cosmic spin.
Source: University of Hawaii at Manoa.
