Giovanni Barontini watched time emerge inside a universe made from ultracold atoms, with no external clock to guide it. The experimental physicist at the University of Birmingham published the study on June 11 in Physical Review Research.
He said the surprising part was how time inside the system was “speeding up, slowing down, or even stopping.” Barontini also described the setup as a place where he and other researchers can “create our own small samples of reality.”
Giovanni Barontini’s mini-universe
Barontini built the system as a Bose-Einstein condensate in a trap, then divided it down the middle with a thin sheet of laser light. He split it into a bright sector and a dark sector, and ignored the dark half while watching the bright side move.
The bright sector sloshed back and forth in the trap and periodically spilled over the barrier and back again. That motion let Barontini trace how the system evolved from within, rather than against an outside clock.
Physical Review Research study
The work tested relational time, the idea that time can emerge from relationships inside a system instead of from an external parameter. It also drew on the Wheeler-DeWitt equation, which treats the universe as a whole system with no outside time variable, an idea discussed for nearly 60 years.
Barontini said, “When you put everything together, things really start to make sense.” He added, “How time inside the system was speeding up or slowing down, or even stopping — this was quite surprising, how well everything came together. Very neatly, in a way. Which is something that doesn't happen that often in experiments.”
Wheeler-DeWitt equation and time
The study is described as the first experimental look at why the universe has time at all, and the first direct, quantitative lab test of ideas from quantum cosmology and thermodynamics. It does not present the result as proof that time is an illusion, even though it probes ideas that treat time as something that emerges rather than something fundamental.
For readers tracking where this line of work goes next, the immediate takeaway is narrower: a closed system can be built, divided, and watched closely enough to show time-like behavior from inside it. Barontini’s result answers part of a long-running theoretical puzzle, but the study leaves the next step to the same kind of lab work that produced it.
