Bells Inequality

There are three conclusions that may be drawn from it, any or all of them may be true:

Deductive logic is broken
There is no reality separate from its observation
Information can travel faster than the speed of light.

: In 1975 Stapp called Bell's Theorem "the most profound discovery of science." Note that he says science, not physics.

http://www.mathpages.com/rr/s9-07/9-07.htm

provides a much more understandable explanation of the meaning of BellsInequality; it means nothing. Chapter 9.6 provides a lucid explanation of von Neumann's "proof" that hidden variable theories are impossible.

For me, it just explains that the BellsInequality means nothing to the author. Who is the author, by the way?

But I am actually not interested in such things as "free will", "causation" and "violent motion". What is meaningful to me is whether we can create a physical model that does not need to consider the presence of the observer, is supported by the observable facts and is no more complex than the current quantum-mechanical model. And the results of the experimental tests of the BellsInequality suggest that we cannot. --NikitaBelenki

It seems like a bit of a leap to go from "spins have no reality separate from observation" to "there is no reality separate from its observation." Everyone agrees the electrons are there, right?

I agree with the first sentence, but perhaps not with the second (what exactly does "the electrons are there" mean?).

Well, just for example purposes, you can count electrons using net charge; charge isn't mutually-unknowable with any other quantities, so shouldn't it be above the problem?

Additionally, there's not much point to discussing "unobservable realities" so the topic is more or less uninteresting.

No! The issue isn't unobservables, but nonobserved "realities"...the former don't matter, but the second are important. Common sense says they are there, and you could check on them at any time - experiment suggests that for some things, though, they are not there until you check.

What, exactly, is the difference? If you never check something, then why does it matter what it may or may not be? If it is guaranteed to be there when you check, isn't that sufficient? If nobody ever opens the box, why does it matter whether SchroedingersCat is dead or not?

Why, because that is exactly the issue at stake! If you assume to begin with that things may as well not exist when unobserved, than it should come as no surprise that observations define reality. But not everyone assumes this, and indeed it defies common sense in the strict sense of the word. As AlbertEinstein put it, do you really think the moon isn't there when you're not looking at it?

regarding " realities ", hands up who really thinks that it makes sense to talk of reality in the plural, or the Universe in the plural?

Funny. Fortunately physics is not democratic!

Democratic or not, it would nevertheless be interesting to read some reasoned discussion about how or why it could make sense to talk about more than one reality, or more than one universe! OntologicalRelativism anyone ???

In the paper is written, This assumption is an example of inductive logic; of course we assumed the validity of logic in our derivation.

Of course, this is a very dark and odious lie. The assumption was of deductive logic, not inductive logic. It sets a horrible precedent to lie in such a fashion.

The assumption that all electrons behave the same looks inductive to me. The derivation of the inequality is the deductive part.

It is inductive and it's a weakness of the experiments used to prove that reality violates the theorem. The paper handwaves away that weakness by claiming that logic (and implicitly inductive logic) was an assumption of BellsInequality. This is a lie. It's such a transparent lie that I cannot help but feel the author must have know it to be a lie, thereby making it an exceptionally odious lie.

The author discusses the difference and potential failures of inductive logic in the article. Summarizing other people's claims (e.g. logic is invalid) is the purpose of the article; he is not making the claim himself in this article.

There's another alternative. I realized today why for so long I could not understand the publications on BellsInequality. To me it looks like a strawman. When I first set the problem up in my head before having any grasp on QuantumMechanics other than the electron orbit tables (SchrodengerEquation? -> what's that) I set it up in something of a novel way. Using what was already known from SpecialRelativity that spin is a unit vector (or unit half vector) I did some quick transforms in my head and said "cos angle". The form was the experiment that reads the spin must return a boolean (up/down) and cannot fail but it's trying to read a unit vector pointing in some arbitrary direction. Therefore the failure mode is return random and it will return an answer that is not right and the probability of getting the right answer rather than a random answer is proportional to the intensity in the unit vector in the direction being measured. While this took a paragraph to explain I saw all of this in 3 or 4 seconds.

Now "cos angle" is of course the right answer. I suspect some symmetry in the experiment setup cancels out the correction factor that I missed and allowed my simple two dimensional transform to work. I lack spherical trig so I can't actually check. --JoshuaHudson