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Every time in physics (in popsci) I hear that it is not possible to travel faster than light, as this would cause many problems that I do not understand.

On the other side, in Quantum Computing (in advanced university classes) we have been told that the entanglement between two qubits means that if a measurement is made on one of them, the other one is decided instantaneously.

How is this? Does that information travel faster than light?

Since my background is computer science and I don't have much knowledge of physics, I would appreciate an explanation as simple as possible, or some references.

Theo Deep
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entanglement between two qubits means that if a measurement is made on one of them, the other one is decided instantaneously.

This is true, but this does not allow for faster than light communication. If you have one qubit with you and i have one qubit with me and you make a measurement on your qubit, that will mean my qubit is decided . But how does that send any signal ?

Later on, when i make a measurement on my qubit, i get a measurement, just as i would have got some measurement had you not measured first. There is no way for me to know, i got this measurement after you had measured yours or before you have measured yours. Hence, no signal can be sent faster than light using entanglement

silverrahul
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