Heads or tails? If we toss two coins into the air, the result of one coin toss has nothing to do with the result of the other. Coins are independent objects. In the world of quantum physics, things are different: Quantum particles can be entangled, in which case they can no longer be regarded as independent individual objects, they can only be described as one joint system.
Source:
https://phys.org/news/2021-02-entangled-atoms.html