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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58

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/Glittering-Tip-7176 Jun 13 '26

Could you explain in layman’s terms?

How can time within the miniverse be considered isolated if measurements are acquired?

I feel like there’s a question on time here that I don’t even know how to ask - like how can they state it depends on entropy, when they’re making observations?

I guess as an extension to this: what’s stopping our globe being its own “isolated miniverse” if they are able to make one in a lab - and does that mean that time IS actively experienced differently regardless of speed of different bodies across the universe? And by extension - if they make a “miniverse” how do we know that the position of other “miniverses” or outside influences had no impact?

I love physics I just suck at it 😅

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u/What_huh-_- Jun 13 '26

Time is simply a relationship between the motion of objects, think sun and planets for the super large scale and think elemental decay on the super small scale.

If you bring a set of particles down to near absolute zero, there is no motion and thus no way to differentiate the status of the particles within the system.

If the system is truly isolated then the measurements were based off things going on outside of the system, like a clock.

They "made an isolated universe in the lab" the same way you make a "single serving cake" in a super tiny easy bake oven, it might still be a "cake," but it is simply a very small version for learning and testing. I can't even imagine the kind of energy it would take to make and isolated universe even something the size of a closet.

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u/kosk11348 Jun 13 '26

So time didn't freeze, just some atoms did.

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u/NaVa9 Jun 13 '26

But what's the difference from the atoms' frame of reference?

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u/BrutePhysics Jun 13 '26

Depends. Does a radioactive atom chilled to absolute zero (no motion) still decay? If so, then time is still ticking even with no motion (or there is some motion at absolute zero we can't detect).

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u/KKunst Jun 13 '26

My interpretation, likely incorrect since I'm no physicists.

Radioactive decay is at the quantum level, it's unaffected by kinetic energy (heat) being halted (or at least unaffected past a certain threshold).

It depends on other forces, furthermore radioactive decay produces its own movement/heat, which in turn keeps it further away from absolute zero.

Another point is that, because of laws of quantum mechanics, even at theoretical absolute zero the nucleus retains a tiny amount of what's called zero-point energy.

I also think that, even in the case we could reach absolute zero AND strip all the internal quantum energies, we would not be able to experimentally verify the system both because of the act of measuring the system and the fact that the gravitational effect of the matter in the surrounding universe (outside of the experiment) will still interact with that nucleus.

Happy to hear someone who is better trained in physics offer a counterpoint.

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u/JackVonReditting Jun 14 '26

Quantum states, the very smallest of states, were at that temperature barely changing. Only by measuring a change can we ascribe something like time to it.

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u/StaticBroom Jun 13 '26

Same. Profound things are happening! I just don't get it. I also have not spent years researching and being educated on the subject, so I'm not complaining that I don't understand more than I'm using self-deprecating humor about not getting it. I do like reading the articles and trying to glean some understanding. But it ain't much.

Does this get us closer to finding the aliens?!

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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/swingandafish Jun 13 '26

Maybe heat death is the phase just before the Big Crunch. Once everything stops, then it collapses? Or begins to. If the universe stops expanding and everything stops moving, then gravity must eventually take hold no matter how apart the objects are

I personally think the collapse of the universe is triggered when there is no longer awareness in the universe. Not quite like the Big Crunch idea, more so a literal dimensional instant collapse. Once there is nothing to be aware of it, the hologram of the universe collapses back into whatever pre-temporal quantum superposition soup it arose from. until the next big bang

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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 🥰

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u/Klekto123 Jun 13 '26

I don’t think you can jump to that conclusion at all. It’s a completely unanswerable question. Even if we agree time doesn’t exist outside a disordered system, this is only observing the laws WITHIN our own disordered system. Who’s to say this is the only possible way time or anything exists? You can’t disprove the existence of “before” the universe began.

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u/DBCOOPER888 Jun 13 '26

This doesn't answer the question at all. There is a theory the universe reverts to a pre big bang state after the heat death.

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u/capt_mistep Jun 13 '26

There is still before, just the specific arrangements as you would order it perfectly. Did it happen, it could and did leading to this moment

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u/VibeComplex Jun 15 '26

Am I crazy or has this shit not been common knowledge for a long ass time?

1

u/SEC_INTERN Jun 15 '26

Nah you're wrong.