Two entangled fermions each have equal probabilities of being in one of two states (state 1 or state 2).The fermions are separated so that no forces act between them.One of the fermions is then studied and found to be in state 1.What is the probability that,when studied,the second particle will also be found in state 1?
A) 0%
B) 33%
C) 50%
D) 67%
E) 100%

Question

Quizplus · Accepted Answer

When two fermions are entangled, measuring one fermion in a particular state determines the state of the other fermion due to the principle of quantum entanglement. Since fermions obey the Pauli exclusion principle, they cannot be in the same state. Therefore, if one fermion is found in state 1, the other must be in state 2, making the probability 0% that the second fermion is also in state 1.

Two Entangled Fermions Each Have Equal Probabilities of Being in One