An international team of researchers has conducted an experiment that shows that the arrow of time is a relative concept and not an absolute one.
Scientists have shown that the arrow or asymmetry of time continues to be one of the great mysteries of the Cosmos.
The name was given by Arthur Eddington and refers to the experience we all have that time always flows in a unique direction, from the past to the future.
In a document made available on the arXiv server, the team describes its experiment and its result and also explains why its findings do not violate the second law of thermodynamics.
The second law of thermodynamics says that entropy, or disorder, tends to increase over time, which is why everything around us seems to develop over time.
It also explains as to why hot tea cools down instead of heating up.
In this new effort, researchers found an exception to this rule that works in a way that does not violate the rules of physics as they have been defined.
“The idea of entangled particles has been in the news a lot lately as researchers around the world attempt to use it for various purposes—but there is another lesser-known property of particles that is similar in nature, but slightly different. It is when particles become correlated, which means they become linked in ways that do not happen in the larger world. Like entanglement, correlated particles share information, though it is not as strong of a bond. In this new experiment, the researchers used this property to change the direction of the arrow of time.”
The experiment consisted of altering the temperature of nuclei in two of the atoms in a molecule of chlorine – hydrogen, and carbon.
They made it so that the hydrogen nucleus was hotter than the carbon nucleus, and then they observed in what direction the heat flowed.
The group discovered that when the nuclei of the two atoms were not correlated, the heat flowed as expected, from the hottest hydrogen core to the coldest carbon nucleus.
However, when the two correlated, the opposite occurred: the heat flowed backward in relation to what is typically observed.
The hot core became hotter while the cold core cooled further down. This observation did not violate the second law of thermodynamics, explains the group because the second law assumes that there are no correlations between the particles.