Entanglement is a phenomenon in quantum mechanics where two or more particles become correlated in such a way that their properties are intertwined, regardless of the distance between them. While entangled particles may appear to communicate with each other instantaneously, it is important to note that they do not convey information or messages in a conventional sense.
When particles are entangled, their quantum states become linked, meaning that measuring the state of one particle will instantaneously determine the state of the other, regardless of the spatial separation between them. This instantaneous correlation between the particles is known as "spooky action at a distance," a phrase famously coined by Albert Einstein.
However, it is crucial to understand that this correlation does not enable the particles to communicate information faster than the speed of light. Due to the "no-communication theorem" in quantum mechanics, it is impossible to use entangled particles to transmit messages or signals faster than light. While the measurement of one entangled particle will instantly affect the state of the other, this effect cannot be harnessed for communication purposes.
In practical terms, any attempt to extract information from an entangled particle will result in a random outcome, seemingly breaking any potential communication channel. Therefore, entanglement is primarily studied and utilized in quantum information processing, quantum computing, and quantum cryptography, where it allows for unique applications such as secure communication protocols and enhanced computational capabilities.