Entanglement swapping

Can two particles talk without ever meeting?

Imagine you have a secret message that needs to be passed between friends who live in different cities, but you want to keep the message secure and untraceable.

Picture sending a secret note through a chain of friends. Even if the original sender and the final recipient have never met, the message can still travel securely through others. This is called entanglement swapping.

Example

Alice sends a note to Bob, who passes it to Charlie, and Charlie passes it to Dave. Even though Alice and Dave never met, they can still share a secret message.

Remember this

Entanglement swapping allows particles to communicate indirectly, ensuring secure and untraceable information transfer.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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Physical paradox

Einstein argued entanglement implied either hidden variables or nonlocality

the Pauli exclusion principle forbids

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Aspect ratio (image)

Bell inequality violations confirm quantum nonlocality

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