Add Yahoo as a preferred source to see more of our stories on Google. Theoretical physicists have figured out how to reverse the arrow of time in a quantum system. The arrow of time marches forward.

This is known as time reversal symmetry. In quantum information science, time reversal has attracted great interest due to its applications in multi-time quantum states, simulations of closed timelike ...

Physicists have experimentally reversed electromagnetic waves in time, confirming a theoretical prediction that has stood for decades. The process, known as time reflection, causes a wave to retrace ...