Scientist builds mini universe of 24,000 atoms to measure time without clock
The experiment uses changes in entropy to track the order of events in a controlled atomic system.
A scientist at the University of Birmingham has created a mini universe consisting of approximately 24,000 atoms to demonstrate that time can be measured without a clock, according to The Times of India.
Giovanni Barontini conducted the experiment by tracking the order of events through changes in entropy, which is the measure of disorder in a system.
The atoms used are rubidium, which were chilled to almost absolute zero, or around minus 273 degrees Celsius. At this temperature, the atoms act like a single cloud within a trap.
A laser splits the trap into a bright, observed side and a dark, unobserved side. The internal timer moved forward only when atoms crossed the laser barrier, causing the entropy on the bright side to change.
The experiment showed that when no atoms crossed over, the internal clock stopped, even though an external clock continued to run. This resulted in a disagreement between the two time measurements.
The model could help link general relativity and quantum mechanics, which describe time differently. It may also help scientists simulate conditions following the Big Bang or the theoretical Big Crunch.