"God does not play dice" referred to what exactly?

[dimensionless]

What was Einstein referring to? As I recall Einstein believed some process was non-random, but the general consensus in physics is that it is indeed random.

[russ_watters]

He was expressing his doubts about quantum mechanics.

[Gear300]

yup...he was not very fond of the way quantum theory presented the universe...

[Topher925]

He was expressing his doubts about quantum mechanics.

Specifically about how quantum mechanics revolves around probability distributions and not finite solutions. An odd quote since Einstein was an atheist.

[Doc Al]

An odd quote since Einstein was an atheist.
What does that have to do with it?

Edit: I just realized that you were probably referring to his use of the word "God", not his discomfort with inherent randomness. I'd say that his use of the term was purely a figure of speech.

[russ_watters]

It's just an expression, Topher. It doesn't necessarily imply anything about his faith/lack thereof.

[Oberst Villa]

It's just an expression, Topher. It doesn't necessarily imply anything about his faith/lack thereof.

Hmm.. for an atheist he talked about god quite often: "Subtle is the Lord, but malicious He is not" is another qoute from him.

[Topher925]

Hmm.. for an atheist he talked about god quite often: "Subtle is the Lord, but malicious He is not" is another qoute from him.

Back in his time I think atheists were looked down upon by most cultures and to this day that is still true with some people. I think a lot of people played the god card just to maintain their reputation and image. We all know what happened to Galileo.

[dimensionless]

What specific randomness in quantum theory did he not like?

[Gear300]

Back in his time I think atheists were looked down upon by most cultures and to this day that is still true with some people. I think a lot of people played the god card just to maintain their reputation and image. We all know what happened to Galileo.

yup...people have only scarcely changed...they are apparently still people

[Oberst Villa]

What specific randomness in quantum theory did he not like?

I think he preferred something like this Hidden Variables stuff: Although the outcome of quantum mechanical experiments might appear random to us, they would be deterministic if only someone (god ?) would at some time know the state of this hidden variables. But as far as I understand it, there has been an experiment some decades ago that showed that this hidden variables cannot exist

[Doc Al]

What specific randomness in quantum theory did he not like?
For example: When you measure an observable on a system represented by a superposition of eigenstates of that observable, the probability of getting a particular eigenvalue is given by the square of the corresponding expansion coefficient for the eigenstate. I think that's the kind of inherent randomness that Einstein was referring to.

[Doc Al]

But as far as I understand it, there has been an experiment some decades ago that showed that this hidden variables cannot exist
Those experiments ruled out local hidden variables, not all hidden variables.

[TVP45]

Specifically about how quantum mechanics revolves around probability distributions and not finite solutions. An odd quote since Einstein was an atheist.

I think it is much closer to the truth to say that Einstein was a non-observant Jew. It is difficult for a Jew to remain in the culture (and, to be a Zionist) while completely ignoring G-d.

A Christian generally will not be able to disagree with G-d while yet remaining faithful to the religion. A Jew may well be strengthened in his religion by arguing with, and doubting, G-d.

[Oberst Villa]

Those experiments ruled out local hidden variables, not all hidden variables.

Thanks for the correction Doc Al. I found in the meantime a paper that might be of interest and confirms what you said: "Research on Hidden Variable Theories: a review of recent progresses" http://arxiv.org/abs/quant-ph/0701071
(Section 6 is about Non-Local Realistic theories, i.e. hidden variable theories that have not been ruled out by experiment)

Obviously, I was quite wrong with my assumption that there was one single experiment and that it closed the case for good.

[Bad Monkey]

Re Einstein and "god" references, read:

http://richarddawkins.net/firstChapter,1

[Pythagorean]

I think it is much closer to the truth to say that Einstein was a non-observant Jew. It is difficult for a Jew to remain in the culture (and, to be a Zionist) while completely ignoring G-d.

A Christian generally will not be able to disagree with G-d while yet remaining faithful to the religion. A Jew may well be strengthened in his religion by arguing with, and doubting, G-d.

Einstein wasn't Jewish (religion-wise), he was a deist, not a theist.

[LightbulbSun]

Einstein was a naturalist. So when he mentioned "God" he was referring to the universe.

[Glenn Rudge]

What specific randomness in quantum theory did he not like?

Everything, for example space, on the quantom level has no shape, no plane, it isn't a flat pane that gravity acts as a cushion for like in our space, rather it's everything, at once, and nothing at once. The more you study the velocity of an electron the less you will know about it's where-abouts, like wise.

[jimmysnyder]

What specific randomness in quantum theory did he not like?
When you roll dice, you get random results. However, it was supposed that in principle, if not in practice, you could roll the dice with the same hand motion over and over again and always get the same result. Quantum mechanics says no, the randomness is not just a matter of slight variations in the rolling procedure but is inherent in the system.

If you prepare many samples in exactly the same state they will evolve into different states according to the probability that they should do so. Because they were all in the same initial state, you can't predict which ones will change to which final state. Einstein was unhappy with this and that's what he meant by his 'dice' quote. He proposed that there may be hidden variables. That is, the systems were not all in the same initial state, you only thought they were because you didn't detect differences in those hidden variables.

[nΨmanty]

Of course, we must make concessions for the theory - but the nature of abstract tensors in a defined space, given the ability to compute such a slew of information for the system under analysis, yields a much more pristine result than any of these so called "probability distributions". I would have to agree with the title of the thread.

I do believe, however, that the world is imbued with a fundamental quality that defines determism on one scale (i.e. the quantum level) but free will of sorts on another (the macro--level). This, though seemingly a contradiction, is not.

[LightbulbSun]

Hmm.. for an atheist he talked about god quite often: "Subtle is the Lord, but malicious He is not" is another qoute from him.

He was a naturalist so his definition of "God" referred to the physical laws of nature. He did not believe in a personal god.

[Evo]

The OP has been answered way too many times.