Scientist Builds Miniature Universe to Test Time
Giovanni Barontini used roughly 24,000 chilled rubidium atoms to explore whether time can be tracked without clocks.
Updated on Nov. 2, 2026 in Physics
Giovanni Barontini, a scientist at the University of Birmingham, created a miniature atomic universe to test a hypothesis about time. The experiment showed that time can be measured by entropy changes in an atomic system.
Why it matters
The experiment tests whether time can be tracked without clocks, a question that bears on the two models underpinning physics, general relativity and quantum mechanics, which do not always agree on the nature of time.
The experiment used roughly 24,000 rubidium atoms chilled almost to absolute zero and enclosed in an inescapable trap split by a specially configured laser. When no atoms were exchanged between sides, the internal clock disagreed with the external clock, and it remains unclear how far the method generalizes beyond this setup.
The players
Giovanni Barontini
Barontini is a physicist at the University of Birmingham who designed the miniature atomic universe experiment to test ideas about time.
University of Birmingham
The University of Birmingham is a public research university in the United Kingdom where Barontini conducts his research.
The details
The atoms acted as a collective cloud rather than individual particles, and one side of the split trap was observed while the other was not. The internal timer advanced only as atoms crossed the laser barrier, and researchers tracked the cloud's expansion, contraction, and atomic exchange to reveal the order of events.
Timeline
The article describing the experiment was published on November 2, 2026.
The Big Picture
Physics has long been split between general relativity, which treats time as part of spacetime, and quantum mechanics, which treats it differently, and the two frameworks do not always agree on what time is. This experiment offers a small-scale test of whether time can be defined by entropy changes in a physical system rather than by external clocks.
The experiment is foundational research with no near-term consumer product attached, so any practical application would depend on future work to scale the method. Its relevance to daily life remains speculative, though the authors suggest it could eventually help simulate conditions after the Big Bang or before a Big Crunch.
The takeaway
Time may be measurable through the changing entropy of a physical system, not only through clocks. That reframing gives physicists a new lab-scale handle on a question that the two dominant theories still answer differently.
Further reading
Explore more in the Physics section for related research on how scientists probe the nature of time.
