In a unique experiment, an international group of scientists stated that it is possible to turn back the clock without violating the second law of thermodynamics. It says that all spontaneous processes in nature are characterized by unidirectionality. So, for example, hot bodies inevitably cool over time, while cold bodies by themselves never heat up.
However, scientists still managed to prove that this thermodynamic "arrow of time" is not an absolute concept. During the experiment, they used correlated particles, conceptually similar to the entangled particles used during quantum research.
The researchers began an experiment with a molecule of trichloromethane, made up of hydrogen and carbon. They made the nucleus of the hydrogen atom warmer than the carbon atom, while observing the flow of energy.
As long as the cores were uncorrelated, the heat spread as expected - from the hot core to the cold, but as soon as they were correlated, the heat flowed back, back to the hot core, which made it even hotter and the cold one colder.
According to the research, during the research, the second law of thermodynamics was not violated, since it does not take into account correlated particles. In other words, the experiment recorded only an exception to the rule.