# Particles entangled after the big bang

Is that true that the big bang caused the quantum entanglement of all the particles of the universe so every particle is entangled to each other particle of the universe?

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For example, if the initial state is a (maximally entangled) singlet state of two spins $$\frac{1}{\sqrt{2}} \left( |\rm up\rangle |\rm down\rangle - |\rm down\rangle |\rm up\rangle \right),$$ the measurement of the first spin yields either "up" or "down" which means that our knowledge of the spins is changed to either "up down" or "down up" (that's the "collapse" of the wave function). The states "up down" and "down up" describe just factual values of two spins that are perfectly known and there is no longer any reason to talk about correlations or entanglements when we know the actual values.