Scientists make quantum time flow backward in stunning physics breakthrough
Key takeaways
- Scientists have developed a new way to control quantum systems that can make their behavior appear more consistent with time moving backward rather than forward.
- A quantum system, such as a group of qubits, follows the rules of quantum mechanics rather than classical physics.
- "In other words, those laws of physics are symmetrical under time reversal; the equations work just as well if you reverse time.
Why this matters: new research or scientific developments with potential real-world impact.
Scientists have developed a new way to control quantum systems that can make their behavior appear more consistent with time moving backward rather than forward. The research, published in Physical Review X, introduces quantum control protocols that reshape a system's "arrow of time," the concept that time naturally moves in only one direction. The approach could eventually support new methods for extracting energy from quantum systems and preparing quantum states.
A quantum system, such as a group of qubits, follows the rules of quantum mechanics rather than classical physics. Using the newly developed control protocols, researchers can suppress the usual emergence of the arrow of time or even reverse its apparent direction, making quantum processes look as though they are unfolding backward. As a demonstration of the technique, the team also created a measurement engine that can harvest energy from the act of making quantum measurements.
"Unlike phenomena we observe around us, at the microscopic level most fundamental laws of physics see forward and backward movement in time as physically possible," said Los Alamos National Laboratory physicist Luis Pedro Garc a-Pintos. "In other words, those laws of physics are symmetrical under time reversal; the equations work just as well if you reverse time. For quantum systems, which operate at that microscopic level, the tools we've constructed can manipulate the perceived arrow of time, leading to surprising, novel ways to control quantum systems."