There are few concepts in physics that are mentioned as much as the concept of time. In the original theory of relativity proposed by Einstein, time is not an absolute value. The passage of time is dependent on motion and dependent on gravity, which could not be proven until recently. In a new theory, when combined with quantum physics, the relative form of time becomes much more intuitive and understandable. According to this quantum theory, the flow of time itself may exist in quantum superposition, which means that it can tick both faster and slower at the same time.

In this work, a team was led by Assistant Professor of theoretical physics at Stevens Institute of Technology Igor Pikovski, where they explored the quantum aspects of the flow of time and how this flow can be accessed and modified with atomic clocks. The results suggest that this same technology that is used in these quantum experiments may soon discover something substantial about the quantum realm.

Time’s movement, in quantum mechanics, can exist in superposition with the recorded passage of time itself, essentially meaning that time can exist however it wishes on the flow that already happened, meaning it can speed itself up or down on the quantum level. This concept is very similar to the idea of Schrödinger’s cat, where before opening the box, the cat is both alive and dead, as while it is inside the box out of sight, it technically doesn’t exist to the eyes. In a way, a person can think of the cat in the box as both young and old when it pertains to quantum time.

“Time plays very different roles in quantum theory and in relativity,” Pikovski said. “What we show is that bringing these two concepts together can reveal hidden quantum signatures of time-flow that can no longer be described by classical physics.” In this relative theory, every single clock can experience its own flow of time, which will depend on the velocity and position of multiple factors.

For instance, if a clock was moving at 10m/s for approximately 57 million years, then it would lag just behind another clock at rest by just one second. While that may not sound like a lot it has some real world implications such as high-speed travel over the long term in space were the technology to become available in the future. It would mean that two people could potentially age at a different rate, despite starting at the same age.

“Even at the absolute zero temperature, the ground state, the ticking rate will still be affected by just the quantum fluctuations alone,” Gabriel Sorci, a PHD candidate at Stevens Institute of Technology and a co-author of the study, said. The team then went on to cool the atoms within the quantum zone, so that they could artificially change the position and velocity of these clocks with incredible precision.

Were this technology to be improved upon and potentially enlarged beyond just subatomic particles, it could accelerate research in supersonic travel and particle acceleration research, both things which serve incredible purpose in the future of our world.