University of Birmingham researcher Professor Giovanni Barontini has successfully simulated a miniature universe using 24,000 ultracold atoms, providing the first controlled experimental evidence that time emerges from internal system disorder rather than an external clock. Published in Physical Review Research, the study demonstrates that time functions as a property of entropy, offering a new framework for physicists to investigate quantum gravity and the early moments of the cosmos.
How does a laboratory-made universe define time?
Professor Barontini’s model functions by trapping 24,000 atoms at temperatures just above absolute zero. By applying two distinct laser frequencies, the team created a hermetically sealed system divided by a thin barrier, resulting in observable “bright” and “dark” regions. According to the study, this system acts as a self-contained universe where time is not a pre-existing container, but a byproduct of the system’s own evolution. As the atoms spread, they create disorder, or entropy, which effectively functions as an internal clock. This suggests that time is an emergent property created by the interactions of particles within a system, rather than an external force ticking away in the background.
The “bright” region of the experiment was observed to cycle through repeated Big Bangs and Big Crunches. This internal “fast-forward” expansion and collapse happens entirely without reference to any external laboratory equipment, proving the system generates its own temporal flow.
Why does this matter for quantum gravity?
The primary challenge in modern physics is the conflict between General Relativity, which relies on a steady flow of time, and quantum mechanics, where time is often absent from basic equations. Professor Barontini notes that in many quantum gravity theories, time is not a built-in feature. By showing that Schrödinger’s equation remains valid even when time is defined by entropic changes, this research bridges a gap between two previously incompatible fields. It provides a testbed for researchers to observe how dynamics function in environments where conventional, linear time may not apply.
What are the future applications of artificial universes?
Laboratory-grown quantum systems allow scientists to probe phenomena that are otherwise impossible to observe in the vastness of space. Future research using these cold-atom models could help explain the behavior of black holes or the specific conditions of the universe’s origin. By manipulating the entropy levels within these 24,000-atom systems, physicists can simulate different gravitational conditions to see how quantum laws hold up under extreme stress. This creates a practical path forward for testing theories that were previously confined to mathematical models.
To understand the difference between conventional time and entropic time, consider that conventional time is like a metronome, while entropic time is like a sandcastle eroding. One is an external constant; the other is a measurement of the system’s own transformation.
Frequently Asked Questions
Is this the same as a computer simulation?
No. Unlike a digital simulation running on a computer, this is a physical, quantum system made of real atoms. It is a tangible “miniature universe” that obeys the laws of quantum mechanics directly.
Does this prove time is an illusion?
The study does not claim time is an illusion. Instead, it proves that time is “emergent.” It shows that time is a consequence of how a system changes, rather than a fundamental “background” stage upon which events happen.
Can this research help build a quantum computer?
Yes. The techniques used to maintain 24,000 atoms at temperatures near absolute zero are foundational to quantum computing. Advancements in controlling these systems often have direct applications in improving qubit stability.
What are your thoughts on the nature of time? Does the idea of an “emergent” clock change how you view the universe? Join the conversation by leaving a comment below or subscribe to our newsletter for more updates on the latest breakthroughs in quantum physics.
