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Bishop · 2007-01-14 01:22:51

I was reading about the wavefunction collapse in QM and I tried to think about an anology for it that would help me get my head around it. Now, it seems like a pretty foreign idea when compared to other physical properties and theories, but I started thinking about communication and human language and came up with something: the collapse of a waveform seems (to me at least) to sound pretty similar to what happens when you acquire knowledge in a very human setting. Say there's an object in a dark room that you know nothing about, and someone tells you that it's "square" - well this collapses the vague idea you had about it and immediately (read: INSTANTANEOUSLY) removes the possibility of it being "round".

So it occurred to me that the collapsing of a wavefunction seems unlike a physical event, and instead seems like a conversion of physical possibilities into knowledge - that the strangeness of wavefunction collapse is because the wavefunction is passing from the physical world to the human world of language and knowledge, and that transition causes an abrupt "bump" in the mathematics.

I don't know if this makes a lot of sense. Well, actually, I'm pretty sure it doesn't. But I just wanted to see if I was *completely* out to lunch, or whether this idea of wavefunction collapse has a possibility of holding water.

Bishop · 2007-01-21 00:56:18

Does anyone even answer anything on this forum?? This sucks.

Chris · 2007-01-21 02:42:27

Does anyone even answer anything on this forum??

Did you have a specific question?

I'm not sure your dark room situation is completely analogous, though you're not far off base. When you observe something, then that something is what it is. Until you observe it, you don't really know exactly what it is, but you can figure out what it probably is.

BenTheMan · 2007-01-21 03:44:13

Hi Bishop---I generally try to answer posts like this one....I must have missed it.

Ok collapse of the wavefunction. This seems like a good abstract way to think about it, but I would caution you reading too much into this. The wave-function is not a physical thing, it only tells you probabilities. You are correct in saying that "the collapsing of a wavefunction is unlike a physical event."

Let me think about this some more and I will get back to you:)

Bishop · 2007-01-22 18:41:58

Chris wrote:
Did you have a specific question?

Okay, sorry, I didn't technically use a question mark. I just wanted to generally discuss my idea...

And it's my understanding that there is quite a controversy on how to interpret the wavefunction, with views ranging from it being a mathematical abstraction to it being more concrete than every day objects. It just occurred to me that this bizarre occurrence of the wavefunction collapsing, which is an alien idea when in the context of classical "middle-range' physics, is actually pretty straightforward and understandable - when viewed in the context of grammar and language. This sort of instantaneous collapse of possibilities happens all the time in language. And so maybe when you try to funnel "reality" (dealing with probabilities and ranges) into human language and human knowledge (dealing with hard, but maybe arbitrary, definitions) you get the jump of the wavefunction collapse. (I've said this all in the first post - just restating it...)

I guess what I need answered to disprove this, is whether something like spin, say, is really and truly a fundamental property of reality, existing as spin without us, or whether it's a definition that we impose. Is there, say, another version of the quantum numbers? I mean, given n, l, ml, and ms, is there another set of numbers you could map to that does the same job of describing the system? Or are these things just out-and-out fundamental?

Am I making any sense??

Chris · 2007-01-23 22:05:43

And it's my understanding that there is quite a controversy on how to interpret the wavefunction, with views ranging from it being a mathematical abstraction to it being more concrete than every day objects.

You are correct that there are MANY interpretations. I'm not quite sure I would call it a controversy, since most physicists recognize that such a discussion is philosophical and not physical (at least as it pertains to quantum mechanics.)

This sort of instantaneous collapse of possibilities happens all the time in language.

I'm still not quite sure I understand your analogy. Are you suggesting that if I'm looking at a ball it doesn't become a ball in my mind until it is called a ball? OR are you talking about having a conversation that you are not quite following until the other person becomes more clear? (This exact discussion may end up being an example, if this is the case ).

... whether something like spin, say, is really and truly a fundamental property of reality, existing as spin without us, or whether it's a definition that we impose.

Well, in a sense, the concept of spin is a fabrication. It's possible an alternative "concept" could be devised that is mathematically equivalent, however it would just be another way of saying the same thing. Your question delves into metaphysics and epistemology, which are areas inaccessible to physics. (That isn't to say they aren't interesting.)

Nicholas · 2007-09-22 02:28:21

Light collapses the wave function. waveless electron light.

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#1 2007-01-14 01:22:51

Wavefunction collapse

#2 2007-01-21 00:56:18

Re: Wavefunction collapse

#3 2007-01-21 02:42:27

Re: Wavefunction collapse

#4 2007-01-21 03:44:13

Re: Wavefunction collapse

#5 2007-01-22 18:41:58

Re: Wavefunction collapse

Chris wrote:

#6 2007-01-23 22:05:43

Re: Wavefunction collapse

#7 2007-09-22 02:28:21

Re: Wavefunction collapse

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