Quantum Mechanics, Sklansky and God

[David Steele]

Every couple of months, David Sklansky mentions
something cryptic about QM in a thread about religion.

What I would like to see is a discussion of just how weird things are in QM now with the latest theoretical progress. It would also be nice to hear what David is so concerned about too.

Here is my take:

According to Gell-Mann and others, the so called "quantum weirdness" has been overblown in the popular literature. ( see his book, The Quark and the Jaguar ),
however even his account is a little hard to follow. It goes something like this:

Decoherence gets rid of all the Shrodinger cat problems and other measurement issues. The small stuff is weird but, when small stuff interacts with large stuff, decoherence makes things nearly classical, and no special status to the observer. The brain doesn't collapse the wave function ( there is no collapse ). Also no special human role in this that could some how be connected to religion or free will ( if you think you need randomness for free will, then QM is a source, not sure myself how that helps, I think determinism is also fine for free will, see Elbow Room by Dennett) .

The other plank of his explanation, is that a many worlds theory or reallyConsistent_histories theory is a reasonbable interpretation. This stuff is hard to follow but somehow we dont actually trade a gazillion universes for a working theory, or do we? I can see how the many-worlds idea elliminates all the weirdness in things ( like the slit experiments, Aspect etc ), if all we have to accept is a mathmatical construction and not actual splitting then it seems quite good? Is it something like using imaginary numbers to solve problems that ultimately have real number solutions?

Can those that really understands this physics elaborate?
- and of course the rest of us, feel free to speculate!

Dave

[David Sklansky]

The stuff that bothers me is how photons behave differently depending on whether they are observed. And the fact that they appear to "know" whether their present tracks will be observed even in the future. And how radioactive particles decay with a certain probability from this point forward regardless of how long they have gone without decaying.

[luckyme]

Membranes, spin foams, loop quantum gravity, causal sets, various versions of string theory, twistor, multiverses ... some of them closing in on test cases, may drastically change how we model reality. what seems strange ( which is just an expression of expectation not actuality ) now may be relatively ho-hum 20 years from now.

Why should any current scientific theory bother us on a metaphysical level? The actuality is what it is, there is no need for it to conform to anything, ... nothing is strange from a big picture view, only if we want to make it conform to our evolved primate perspective.

The above theories account for some puzzling aspects of QM, for example ( and raise their own 'weirdness').

luckyme.

[John21]

I'm beginning to wonder if consciousness is some type of quantum effect.

[David Steele]

I am hoping for some better replies but here is a stab:

1) how photons behave differently depending on whether they are observed.

In the slit experiment the photon behaves differently
when you open vs close one slit. It doesn't matter if
someone is examining the measuring screen.

2) And the fact that they appear to "know" whether their present tracks will be observed even in the future.

There are different sets of consistant histories in the
different configurations, including the delayed ones, so
naturally you find the measurement with one of these histories. ( for me it only gets ugly if somehow all the other histories exist).

3) And how radioactive particles decay with a certain probability from this point forward regardless of how long they have gone without decaying.

This never bothered me, but maybe I am missing something.

In a classical atomic model, the pieces of the atom would be orbiting and moving etc. Every once in a while it would find itself in an unstable formation and decay. Same story for the QM model even if the parameters are different.

It seems pretty typical of many processes,hitting your favorite roulette numnber, getting AA UTG in HE etc, that not seeing the event doesn't change the time expectation for it to occur. I suppose other things use the rotting food model, but why expect that here?

Dave

[David Steele]

I'm beginning to wonder if consciousness is some type of quantum effect.
You and Roger Penrose, but not me.

I am satisfied that human interaction plays no role in physical phenomena other then obvious things ( like stepping on the apparatus ) and that consciousness also plays no role.

D.

[SocalHoldEem]

[ QUOTE ]
I'm beginning to wonder if consciousness is some type of quantum effect.

[/ QUOTE ]

This has been proposed. It also plays a role in both the Red Mars book series by Kim Stanley Robinson and the Hominid series by Robert J. Sawyer

[evank15]

[ QUOTE ]
And how radioactive particles decay with a certain probability from this point forward regardless of how long they have gone without decaying.

[/ QUOTE ]

What do you mean be "how long they have gone without decaying"?

Alpha decay is based on specific quantum mechanical transmission probabilities. These probabilities are dependant on the fundamental properties of the specific atom. They cannot be changed.

Maybe I'm misunderstanding what you're saying.

[John21]

[ QUOTE ]
I'm beginning to wonder if consciousness is some type of quantum effect.
You and Roger Penrose, but not me.

I am satisfied that human interaction plays no role in physical phenomena other then obvious things ( like stepping on the apparatus ) and that consciousness also plays no role.

D.

[/ QUOTE ]

Wouldn't that invalidate Bell's theorem?

It's my understanding that if the quantum phase connection is real, then it links 'all' systems that have once interacted (not just twin-state photons).

[JMAnon]

[ QUOTE ]


1) how photons behave differently depending on whether they are observed.

In the slit experiment the photon behaves differently
when you open vs close one slit. It doesn't matter if
someone is examining the measuring screen.
[b]


[/ QUOTE ]

I don't think he was referring to the slit experiments, but to the experiments showing violations of bell's inequality.