Current cosmological models hold that the universe expands uniformly in all directions without any rotation.
A new study published in the Monthly Notices of the Royal Astronomical Society suggests that the universe may be rotating — albeit extremely slowly — a discovery that could help resolve one of astronomy’s most persistent puzzles, the “Hubble tension.”
The research was led by Istvan Szapudi of the University of Hawaii Institute for Astronomy.
Current cosmological models hold that the universe expands uniformly in all directions without any rotation. This framework explains much of what astronomers observe but fails to reconcile conflicting measurements of the universe’s expansion rate.
The so-called Hubble tension arises because two primary methods yield different expansion values: one based on distant supernovae and galaxy distances reflecting the recent universe, and another using the cosmic microwave background radiation from the early universe about 13 billion years ago.
Szapudi and his team developed a mathematical model that incorporated a tiny amount of rotation into the universe’s expansion.
Remarkably, this slight twist resolved the discrepancy between the two expansion rates without contradicting existing astronomical data. “Much to our surprise, we found that our model with rotation resolves the paradox,” Szapudi said, paraphrasing the ancient Greek philosopher Heraclitus: “Panta Kykloutai”—everything turns.
Their model estimates that the universe could complete one full rotation every 500 billion years—far too slow to detect directly but sufficient to influence cosmic expansion over time.
Importantly, this idea does not violate any known physical laws.
The next phase of research involves creating comprehensive computer simulations to further test the rotating universe theory and identify observational signatures of this slow cosmic spin.
If confirmed, this paradigm shift could deepen our understanding of the universe’s dynamics and solve the longstanding Hubble tension that has puzzled astronomers for years.
