The assertion that entangled particles can exhibit non-local effects, often referred to as "spooky action at a distance," is a common description used to illustrate the peculiar nature of quantum entanglement. It suggests that the instantaneous correlation observed between entangled particles implies a form of communication or influence faster than the speed of light.
However, it's important to clarify that this description does not imply actual communication or information transfer in the conventional sense. The no-communication theorem in quantum mechanics states that it is impossible to use entanglement to transmit information faster than the speed of light.
When two particles are entangled, their quantum states become correlated in a way that measuring one particle instantaneously affects the state of the other particle, regardless of their spatial separation. This phenomenon is a consequence of the mathematical formalism of quantum mechanics.
While the entangled particles exhibit a non-local connection, it does not enable the transfer of information. The reason is that the observed correlations cannot be used to transmit signals or communicate in a way that violates the principles of causality or relativity.
The apparent faster-than-light influence arises because the measurement outcomes of one particle are instantaneously correlated with the corresponding outcomes of the other particle. However, this correlation cannot be exploited to send any meaningful information from one location to another at speeds faster than light.
The violation of Bell's inequalities and experiments such as the Aspect experiment confirm the non-local nature of entanglement. These experiments demonstrate that the correlations observed between entangled particles cannot be explained by local hidden variables, suggesting that the entanglement involves non-local connections.
In summary, while the description of entanglement as "communication faster than light" is sometimes used metaphorically, it is important to understand that it does not enable the actual transmission of information faster than light. The non-local effects of entanglement are a fundamental feature of quantum mechanics, but they cannot be exploited for practical communication or violate the principles of relativity.