[Dave Wright]

The cat thought experiment follows exactly the same rules as the quantum particle entanglement does. Using a truly random event such as radioactive decay to determine whether the poison vial is broken or not ensures that the state of the cat and the poison vial are entangled in the box system which hides our view inside.

We don’t know which state the cat (particle) or the poison vial (particle) is in until we observe at least one of them.

If we could divide the box and send just the vial half to a distant galaxy someone there could open it and see the random state of the vial, either intact or broken. They would immediately know the state of the cat (dead/alive) even though it was light years away. The entangled cat and vial states share the same probability density matrix and the state of one is correlated with the state of the other. It’s not spooky, just a little cruel for a thought experiment

[Right_Wing_Madman]

The cat thought experiment follows exactly the same rules as the quantum particle entanglement does.

Yeah, quantum mechanics tangled up the author of this article too. Schrodinger's cat is indeed dead and alive at the same time. And to take it one step further, the observation or measurement of a phenomenon does not influence its outcome, but determines its outcome.

[.44 Special]

By the time the vial got to the alternate universe you can bet your ass that the cat would be dead.
Alternatively, the cat would have been killed by a deranged freeper such as yours truly.