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Q & A: God's dice

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Most recent answer: 10/22/2007
What did Albert Einstein mean when he said "God doesnít play dice"? I canít remember where I heard it, but someone said that this universe is ruled by numbers. What do they mean? Is it true?
- Anonymous
Alexandria, Va, USA

In quantum mechanics, many events look like they happen by absolutely random chance. Exactly when a radiactive decay occurs, exactly where a particular blip of light gets absorbed, etc seem not to be determined by anything in the way the universe is ahead of time. Einstein strongly suspected that these events all did have specific causes, but that the causes were somehow hidden away in some hard-to-find form. That's what he meant when he said "God doesn't play dice with the universe."

Since that time, mostly over the last thirty years, people have followed up some of Einstein's ideas for experiments intended to show that the consequences of standard quantum mechanics are absurd. The experiments have not only confirmed quantum mechanics, but have convincingly shown that if the universe has "hidden variables" to dictate the outcomes of quantum processes, those variables are simultaneously hidden all over the place, not in any particular location. So it looks like Einstein's hunch was probably wrong.

As for whether the universe is 'ruled by numbers', I guess you mean that the most general reliable truths we've found out about the universe take the form of mathematics. As Galileo put it, the universe "is written in the language of mathematics." In some form that idea goes back at least to the Pythagorean school in Greece. We don't really know what made the Pythagoreans believe it- they didn't have any decent evidence- but now it certainly seems to be true.

Mike W

(published on 10/22/2007)

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