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I was just reading about quantum entanglement and the example was the Double-Slit Quantum Eraser Experiment. Then this was used as a basis for saying that particles might be half a universe apart and still be just as connected.

So I was just wondering if entanglement experiments have been done to show that this is really the case or if it is considered "academic" to conclude that there's no difference when the distances are huge?

As a side query, quantum mechanical interference seems to be based on the existence of probability - does this mean probability should be thought of as something as tangible as matter/energy?

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The existence of probability is a mathematical definition. It's just as natural and tangible as the number 2. – Malabarba Aug 12 '13 at 22:01
I always thought probability was an abstraction... – Aaron Anodide Aug 12 '13 at 22:48
@BruceConnor That's not really true, since probability can have different definitions and some experts still argue about which one is the right one. See Wiki for example. Regarding your question Aaron, a common view is that probabilities encoded by the wave function are not something tangible but only represent degrees of belief in the mind of the observer, helping him/her to predict the outcome of experiments. Others such as Vedral have proposed that these probabilities/information are physically real – Mark Mitchison Aug 13 '13 at 0:29
Haha... fine I got ahead of myself :-) – Malabarba Aug 13 '13 at 9:07
@AaronAnodide And so is $2$. Most people believe $2$ exists. (I actually don't. But that's a good thing. If $2$ doesn't exist, it can never cease to exist.) – PyRulez Jan 16 at 22:24

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