Quantum entanglement allows particles to be connected across vast distances instantaneously.

Quantum entanglement is a phenomenon where two particles become connected in such a way that the state of one particle is directly related to the state of the other, even if they are separated by large distances. This connection is maintained instantaneously, defying the constraints of classical physics. This concept has been experimentally verified through various tests and is a key aspect of quantum mechanics that continues to fascinate scientists and laypeople alike due to its seemingly "spooky" action at a distance.