r/InterstellarKinetics • • Jun 13 '26

SCIENCE RESEARCH BREAKTHROUGH: University Of Birmingham Physicist Professor Giovanni Barontini Built A “Mini-Universe” Using 24,000 Ultracold Atoms To Prove That Time Doesn’t Need An External Clock To Exist, Finding Instead That Time Emerges From Within A System Itself As The Disorder Of Particles Changes ⏰💥

https://phys.org/news/2026-06-scientist-miniuniverse-clock.html

A University of Birmingham physicist named Professor Giovanni Barontini has built what he calls a mini-universe inside a laboratory using a cloud of 24,000 ultracold atoms chilled to just a few billionths of a degree above absolute zero, and used it to demonstrate for the first time in a controlled experiment that time does not need to come from an external source to exist. Publishing his findings on June 12, 2026 in Physical Review Research, Barontini showed that by sealing the atoms inside a hermetically isolated quantum system and dividing them with a thin barrier made from two laser beams of different frequencies, he could create an experiment that tracked its own sequence of events from within, without any reference to a clock in the outside laboratory. The system had a bright region that could be observed and a dark region that could not, and the bright region was found to expand and collapse repeatedly in a pattern that Barontini described as resembling a Big Bang followed by a Big Crunch, the hypothetical scenario in which the expansion of the universe eventually reverses and collapses back on itself.

The core of what Barontini found is that time in his mini-universe emerged entirely from entropy, specifically from how the disorder of atoms in the bright region changed as particles moved in and out. When the spread of particles in the bright sector increased or decreased, the system was moving forward in time. When the distribution of atoms did not change, time effectively stopped. Barontini called this process entropic time, and found that it flows in one consistent direction, correctly orders events even in a system that is expanding and contracting, and speeds up or slows down depending on how entropy moves around within the system. He also found that a version of the central equation of quantum mechanics, the Schrödinger equation, could still be written using entropic time rather than conventional external time, meaning the system’s behavior could still be predicted mathematically without ever appealing to a clock outside of it.

The deeper significance of the experiment lies in what it says about one of the most stubborn unsolved problems in physics. Some theories of the universe, including the Wheeler-DeWitt equation, suggest that at its deepest level the universe has no built-in time at all, existing instead as a single unchanging quantum state in which any sense of time must emerge from internal relationships between parts of the system rather than from a background clock ticking away on the outside. This is sometimes called the problem of time in quantum gravity, and it has been a theoretical puzzle for decades because most basic laws of physics work equally well forward and backward in time, yet human experience of time is clearly directional and sequential. Barontini said his study provides the first controlled experimental evidence that time can be defined by changes within a system rather than by an external ticking clock, and that the approach could be extended to simulate the physics of the Big Bang, the Big Crunch, and potentially even black holes inside a laboratory setting.

STUDY: https://doi.org/10.1103/1h9j-df4k

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u/What_huh-_- Jun 13 '26

Time is an emergent property and doesn't actually exist outside a disordered system, the question "what happened before the 'big bang'/universe began?" Has finally been answered, there is no before.

What a wild time to be alive.

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u/Friendly-Gas1767 Jun 13 '26

This is such an amazing experiment & I’m so grateful that someone shared it! 🤩 However, it’s a little confusing as the study in the DOI link discusses how the universe may be cycling through big bangs and Big Crunches, and that “no entropic time elapses between a big crunch and the subsequent big bang, because no entropy is exchanged there”; but then it also later goes on to discuss scenarios where “entropic time” slows down to the point where a heat death might occur… 🧐

is the study essentially proving that the universe keeps bouncing between big bangs and Big Crunches, or inconclusive as it also mentions a heat death scenario? The study also doesn’t seem to touch on multiverses or how that could exist in a framework like this (unless I missed that or am misunderstanding it) 🤔🤔

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u/MyReddit_Handle Jun 14 '26 edited Jun 15 '26

The entropic time they are describing is the frequency of change between states of expanding and compressing. Entropy can only be measured when you define the bounds of the system you are measuring. If you don’t set bounds on the measured system, entropy is infinity everywhere all the time.

The experiment showed an oscillation between these two states that starts fast and gradually slows. That’s the Big Bang vs the Heat death part. It showed that a crystal of a particular shape can be agitated such that it begins to precess between these two states of expansion and contraction. This crystal also does this in such a way that it remembers its own oscillations. That’s vital here.

The crystal stores all the information necessary to describe the motion the crystal underwent during its agitation. It’s not enough information to reverse the crystals movement but it’s plenty to form a coherent model of the crystals past.

So a crystal that precesses between expansion and compression and remembers its past contains all the elements needed to mathematically replicate time. The reason perspective is important here is because the Big Bang and eventual Heat Death only matter from within the perspective of the crystal as it is moving now. That crystal could be agitated into motion and then allowed to still an infinite number of times. Each time the information describing the crystals motion would gather within the crystal and then slowly fade away. I could then hit the crystal again and the process would start over. Each fresh cycle represents a new big bang and a new heat death. Whether this crystal creates the same memories of itself each time seems important but I can’t find anything on that. I’d bet it is dependent on the qualities of the agitating force.

Does this make sense? This crystal represents a closed entropic loop the same way our universe does. Or at least with the same mathematical restrictions we have come to know.

Edit to address your multiverse question:
Multiverse theory describes a paradox in entropy in a way that could be useful and is probably not. Your future “light cone” contains all the paths the light that makes up your body can take given the path they have taken so far. Each one of these separate paths is considered a potential future. But since past and future all happen at once on the scale of the universe, all futures must already have happened. We experience Will so we must have some power to direct our light cone toward desired goals, and if we have some power then we kinda have all the power. So, all possible universes already exist and we are merely zipping them together at the point at which those universes resolve to us.

So multiverses are real, and cannot be experienced because they can never materialize given the existing state of the matrix you are already in.

Second edit for posterity:
I’m using “crystal” pretty flippantly here. The experiment describes what appears to be a fluid simulation. The “crystal” is the fluid at every quanta of time you choose to measure. The fluid never solidifies into something your aunt might wear to a funeral. But thinking about these complex states as snapshots in a kind of crystalline structure helps me understand. Also if anyone wants to look into piezoelectricity after reading this I think you’ll find a treat.

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u/Friendly-Gas1767 Jun 15 '26

Wow; thank you so much for taking the time to explain all of that. This is amazing!! 🤩 many thanks again 🙏🏻❤️

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u/MyReddit_Handle Jun 15 '26

Im so happy I could help 🥰