Darren New wrote:
> Warp wrote:
>>   That's the kind of "observation" I don't understand.
> 
> They're still working on that one.  Someone recently proposed it's 
> actually gravity waves causing the "collapse", which is why it doesn't 
> happen until you get enough particles that gravity becomes significant. 
> Or some such.
> 
> That's another one of those "nobody is sure why yet" kind of things.
> 
Ok. Already gave and answer to why this is odd, but.. Just to let you 
clarify - How do you "measure" or "observe" what a particle as even 
done, without colliding it with something? What process do you use that 
doesn't involve a "state change" resulting directly from a scientific 
instrument *causing* the state to change? There isn't one, so the 
Copenhagen interpretation can't be arguing that "looking at something", 
without actually, you know... "looking at it", does anything. By 
definition, anything you can/do do, which looks at a particle, involves 
*other particles*, so I am unclear what the heck either one of you are 
claiming is different here from any other sort of quantum physics.

Again, we can't measure/observe a particle, without interacting with it, 
so claiming that "changing" it by observation differs from changing it 
by hitting it with another particle is just... not making any sense at all.

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   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>> Darren New <dne### [at] sanrrcom> wrote:
>>>>>   But it seems that everybody knows that it does not happen by the photon
>>>>> going through both slits?
>>>> Correct.  Or, rather, nobody has ever measured anything that would imply the 
>>>> photon goes through both slits as a wave.
>>>   The interference pattern in the detector is not a measurement?
> 
>> No. It's a bunch of individual measurements of different photons. There's no 
>> way to look at *one* photon and decide whether there was one slit or two. 
>> Because it's not a wave, it's a particle, so it always makes the same sort 
>> of single-spot quantum event in a single place.
> 
>   That's like saying that you can't measure the probability of a coin
> giving heads because you can only toss one coin at a time.

No. It's like saying a coin doesn't land half-heads-half-tails. You can 
certainly measure the *probability* of a photon hitting in a particular 
place. That doesn't mean the photon is or ever was a wave.

>   I'd say tossing 100 coins one after another is exactly as valid as if you
> had tossed one coin 100 times simultaneously (if that was physically possible).

Yes. And even tho you get about half heads and about half tails, not a 
single one of those coins wound up with half the heads showing or half the 
tails showing. They were all either 100% heads or 100% tails, when you look 
at each one individually.

Similarly, each photon is a particle, and it never goes through both slits, 
just like a coin never lands 50% heads and 50% tails.

>>>   But I thought that's the whole idea in the Copenhagen interpretation:
>>> Particles are in superpositions until they are measured, in which case
>>> they collapse into a definite state. Thus when you measure a photon, you
>>> will always find a collapsed photon.
> 
>> If every time one measures something, one gets "it isn't a wave", then why 
>> would one think it's ever a wave?
> 
>   Because of the interference pattern?

There's one set of measurements that give the same probabilities as if the 
photons were propagating as waves. But there's also other ways to explain 
the interference pattern (mathematically speaking) that has the same 
arithmetic but a different interpretation. This different interpretation is 
consistent with *all* the measurements.

It's like looking up at the sky and saying "The sun goes around the earth, 
obviously."  But yes, maybe the earth goes around the sun, and you'd get the 
same appearance as the sun, but if you look at other *planets* you can tell 
they're all going around the sun.

>   If it behaves like a wave, what can we deduce from that?

If you flip 1000 coins, and it comes up 500 heads and 500 tails, can we 
deduce that each flip landed half heads half tails?

>   It's an argument that measurement doesn't necessarily tell what was the
> state before the measurement was performed.

But *no* measurement *ever* detects waves. They only detect distributions of 
particles that match the mathematics of complex numbers. Waves also match 
the mathematics of complex numbers. But not everything that matches the 
mathematics of complex numbers is a wave.

>> Yes. But if a photon was a wave, it could interfere with *itself*. It could 
>> split up and go through two separate slits. One photon doesn't make an 
>> interference pattern, and that's how you know the photon isn't a wave.
> 
>   That just doesn't convince me. Just because the photon collapses when it
> hits the detector doesn't mean that on the way it didn't pass through both
> slits at the same time and interfered with itself.

Well, you're arguing the question that has confused nobel-prize-winning 
physicists. I can only try to explain what I understand them to say. I can't 
really convince you per se.

Nobody can figure out what would cause a "collapse", nobody has math that 
explains when the collapse happens, nobody has ever observed a particle in a 
non-collapsed state.

>   It sounds like you are arguing that particles cannot be in superimposed
> states 

No, I'm saying they aren't waves. What's superimposed isn't a "wave", but 
probabilities. Yes, particles are in superimposed states. That doesn't make 
them waves. Since the states particles can be superimposed and tangled up 
with the states of other particles, and that tangling does *not* act like a 
wave, then it's experimentally determined that superimposed states aren't 
waves either. It only looks like a wave if you look at one of them.

> and that there's no collapse phenomenon when they are measured, but
> instead they are always at single places at a time, in particle form.

That's not what I said. You only ever *measure* them in a single place at a 
single time in particle form. How would you really know what it's doing if 
you never observe it doing it?

There are theoretical reasons to believe it's impossible to observe them 
being waves. (Otherwise, they wouldn't be quantum, for example.) Indeed, the 
whole "black body radiation" question that started quantum physics falls 
down if photons are waves in flight, which is why people stopped thinking 
they were waves in the first place: it was impossible to understand 
something glowing hot if light is waves.

> other words, that the Copenhagen interpretation is wrong. (Of course, if
> I have understood correctly, nobody has proven that it's right, but you
> are seemingly claiming it's wrong. Has that been proven?)

I think people are still debating, but as far as I know, all the really 
smartest people think quantum theory comes in quantums. :-) The whole 
problem with the Copenhagen interpretation is that nobody knows why it would 
collapse, nobody has any math to explain the collapse, and it doesn't give 
you any answer better than you get with "it's never a wave", especially 
without being able to explain why it collapses.

Maybe if someone knew what caused the collapse, or under what circumstances 
it happened, you could test if Copenhagen was valid or not. But it doesn't 
make any predictions the always-a-particle theory makes.

>   (Not that I have the slightest idea what I'm talking about. The problem
> I'm having is that, seemingly, people have no idea why the interference
> pattern appears yet are completely sure it's *not* because photons are
> in wave state at any point.)

They know because when you actually put *two* photons together, they *don't* 
make an interference pattern. If photons were waves, you wouldn't get 
lasers, for example. And they wouldn't interact with electrons in the way 
they do, even when you're not "observing" them.

I may have no idea if you start out in your automobile in your driveway 
where you got to, but I'm pretty sure you didn't drive to Hawai'i. :-)

>> You 
>> don't see half the photon's energy hit here and half hit there with a blank 
>> spot in the middle.
> 
>   You don't see it because if you try to see it, the photon collapses and
> the only thing you see is a particle.

I think it's Occam's Razor here. Why postulate a quantum being a wave if (1) 
no observation is capable of ever seeing it as a wave, (2) it behaves in 
ways contrary to it being a wave when in flight, and (3) everything you *do* 
see can be explained without it ever being a wave?

-- 
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   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Patrick Elliott wrote:
> Ok. Already gave and answer to why this is odd, but.. Just to let you 
> clarify - How do you "measure" or "observe" what a particle as even 
> done, without colliding it with something?

You don't. But you can make a measurement after it has done something, and 
change what it "has done" already.

> definition, anything you can/do do, which looks at a particle, involves 
> *other particles*, 

Right. But it might involve *other* particles *after* the measurement of 
interest has been completed.

> Again, we can't measure/observe a particle, without interacting with it, 

Sure you can.  Look up Bell's Inequality, or Quantum Erasers.

http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

> so claiming that "changing" it by observation differs from changing it 
> by hitting it with another particle is just... not making any sense at all.

That's what makes the copenhagen interpretation problematic, yes.


-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Darren New <dne### [at] sanrrcom> wrote:
> I think it's Occam's Razor here. Why postulate a quantum being a wave if (1) 
> no observation is capable of ever seeing it as a wave

  I suppose that means that all phenomena caused by electromagnetic waves
(which light is) has to be explained by non-wave means, such as for example
electromagnetic radiation having a frequency and amplitude, as well as
exhibiting wave-like behavior such as polarization (how can you polarize
a particle given that polarization is by definition a property of waves
that describes the orientation of their oscillations?) and the effect
electromagnetic waves have on electric conductors (which is what radio and
TV broadcasts, among many other things. are based on).

  The effect on eletric conductors is interesting: Electromagnetic waves
cause electrons to move at the same frequency than the frequency of the
incoming radiation, which clearly demonstrates that it does have a
frequency. The amount of movement is proportional to the amplitude of
the incoming radiation, which demonstrates that it does have an amplitude.
The amount of movement is also proportional to the direction of oscillation
of the incoming radiation (something which is also demonstrated by
polarization).

  The double-slit experiment also demonstrates wave-like quality.

  If it looks like a wave, feels like a wave, smells like a wave, what is it?
Not a wave, it seems. It just fakes being one quite well.

-- 
                                                          - Warp

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Patrick Elliott <sel### [at] npgcablecom> wrote:
> It was never intended to be used to imply that the 
> state in such a box could/does exist in the real world.

  AFAIK there's a big difference between an analogy and a thought experiment.

  An analogy is describing in layman terms something complicated. The analogy
is not to be taken literally, but just as a way to visualize the concept
being explained.

  A thought experiment, however, is something which should happen (even if
it's physically unfeasible to put into practice). It's not an analogy, but
an actual phenomenon which should happen if the theory is true and the proper
conditions could be set up.

  Schrodinger's cat is a thought experiment, not an analogy.

> And, if you think about it, it can't be otherwise. If you observe a 
> particle with a detector, the detector "causes" the state change.

  But in the thought experiment the detector already measured the radioactive
particle and caused (or not) the hammer to break the flask. The cat itself
also observes what happens (quite literally). Yet the thought experiment
still maintains that (given that the inside of the box is completely isolated
from the outside), the cat is in two superposed states. Not as an analogy or
figure of speech, but literally.

  If the solution were that simple, it wouldn't be a thought experiment
(with multiple possible explanations) at all.

-- 
                                                          - Warp

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> I think it's Occam's Razor here. Why postulate a quantum being a wave if (1) 
>> no observation is capable of ever seeing it as a wave
> 
>   I suppose that means that all phenomena caused by electromagnetic waves
> (which light is)

I think it's not considered to be an electromagnetic wave any more.

> has to be explained by non-wave means, such as for example
> electromagnetic radiation having a frequency and amplitude, 

Yep. Explained.

> as well as
> exhibiting wave-like behavior such as polarization (how can you polarize
> a particle given that polarization is by definition a property of waves
> that describes the orientation of their oscillations?)

Not in QM. I don't know too much about polarization, but it's not purely 
based on "wave" stuff.

> and the effect
> electromagnetic waves have on electric conductors (which is what radio and
> TV broadcasts, among many other things. are based on).

Sure. Particles of light hitting the metal of the antenna and knocking 
electrons around causes radio reception, for example.

>   The effect on eletric conductors is interesting: Electromagnetic waves
> cause electrons to move at the same frequency than the frequency of the
> incoming radiation, which clearly demonstrates that it does have a
> frequency. 

The change in quantum-amplitude has a frequency, because you're changing it 
in a regular pattern at the transmitter.

> The amount of movement is proportional to the amplitude of
> the incoming radiation, 

It's proportional to the number of photons arriving. If by "amplitude" you 
mean "strength", then yes. If by "amplitude" you mean what people who talk 
about QED mean, then no.

 > which demonstrates that it does have an amplitude.
> The amount of movement is also proportional to the direction of oscillation
> of the incoming radiation (something which is also demonstrated by
> polarization).
> 
>   The double-slit experiment also demonstrates wave-like quality.
> 
>   If it looks like a wave, feels like a wave, smells like a wave, what is it?
> Not a wave, it seems. It just fakes being one quite well.

As I said, the probability of finding a particle in a particular place is 
based on multiplying complex numbers. But since you never actually find a 
wave, but only interference patterns (so to speak), it's probably not a 
wave.  The "wave" properties don't explain *all* the different kinds of 
interference, but only the kinds that interfere like waves do. There's also 
interference patterns that are the opposite of what you'd get with waves 
(lasing vs exclusion principle) that is *also* explained by the theory in 
which everything is a particle.

You really should watch the lectures (or read the book) I pointed you to. 
They do a very nice job of explaining it. Both the video and the book are 
Feynman, who got a nobel prize for figuring out how to explain to other 
quantum physicists how to figure out wtf is going on with quantum mechanics, 
so it's really quite interesting.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
>   Schrodinger's cat is a thought experiment, not an analogy.

It's not even that hard to set up. :-)

I think the point is that you have to question what an "observation" is. If 
the particle gets emitted and runs into the detector when the power is 
turned off, is it "observed"?  If the power is on but the detector isn't 
connected to anything?  If it's connected to a speaker you can't hear? If 
it's connected to poison but there's no cat in the box?  Etc?

In other words, if it takes an "observer" to collapse the wave function, is 
the cat enough of an "observer" to count? If so, how does the human get 
involved? According to the math, the cat is still superimposed. But that 
would imply the cat isn't sufficiently an observer to cause the collapse. 
*Or* that the math doesn't match reality. And multi-worlds is an attempt to 
say "no, the math really matches reality."

-- 
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   Human nature dictates that toothpaste tubes spend
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On 12/02/09 19:06, Darren New wrote:
>> I suppose that means that all phenomena caused by electromagnetic waves
>> (which light is)
>
> I think it's not considered to be an electromagnetic wave any more.

	Throughout this thread (which I admit I did not read all of), you've 
stated stuff a bit too definitively for my taste, as if all the top 
physicists agree on this.

	I can only abuse David Mermin's quote: "Shut up and calculate!"

	I'm guessing that the actual mathematical formalism that we have for QM 
addresses all that is _needed_, in that it always works, and we know of 
no phenomenon (except perhaps gravity) that our mathematical formalism 
fails at. Given that, having an argument about whether it's a wave or a 
particle is philosophy of the pointless kind. The theory will remain 
unchanged.

	I'm truly baffled as to why y'all are arguing so much about this.

	*Knowing* that it's a particle or a wave is not (as far as anyone 
knows) going to change physics, or its rules, or even give better 
results, or allow you to do better calculations. I'm not even sure if 
any of you has bothered to *define* what a particle is or what a wave 
is. Without doing so, the argument becomes even more amusing - 
especially considering that what an electron/photon is may truly not fit 
either one.

	Which is likely the view I favor: Notions of particles and waves for 
things like photons and electrons are somewhat meaningless Heck, a wave 
was "meaningless" for light even before QM was known - what is it waving 
in? I'm sure some of your (Darren's) arguments against viewing it as a 
wave were as applicable in the 1800's, before QM came around.

	Particles/waves, to me, are macroscopic phenomena. Photons and 
electrons are described accurately by the mathematical rules in QM. 
That's all there is. There's really nothing more to know about it. We 
know as much as there is to know about QM as we did classical mechanics. 
Ultimately, the latter was also properly described by a mathematical 
formalism. We had an illusion that we understood that better merely 
because we were used to it in our daily lives. But that's just an illusion.

	(OK, I may be exaggerating a tiny bit in the last paragraph, but the 
main point is that just because it seems "weird" doesn't mean it's any 
weirder than classical mechanics).

>> as well as
>> exhibiting wave-like behavior such as polarization (how can you polarize
>> a particle given that polarization is by definition a property of waves
>> that describes the orientation of their oscillations?)
>
> Not in QM. I don't know too much about polarization, but it's not purely
> based on "wave" stuff.

	In general, are you sure polarization cannot be described just by 
waves? If you have waves in 3-D materials? FYI, the standard model for 
sound waves in solids (i.e. phonons) assumes they have a polarization.

> You really should watch the lectures (or read the book) I pointed you
> to. They do a very nice job of explaining it. Both the video and the
> book are Feynman, who got a nobel prize for figuring out how to explain
> to other quantum physicists how to figure out wtf is going on with
> quantum mechanics, so it's really quite interesting.

	I haven't read the book, but my physics professor said that it's THE 
book to read (QED) if you want to get an understanding of light/EM 
phenomenon.

-- 
Even if you win the rat race, you are still a rat.

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Neeum Zawan wrote:
>     Throughout this thread (which I admit I did not read all of), you've 
> stated stuff a bit too definitively for my taste, as if all the top 
> physicists agree on this.

I'm just stating my understanding of the general consensus. I freely admit 
that maybe they're wrong, but when the guy who got the nobel prize for 
explaining to other theoretical pysicists how it works says "It's never ever 
a wave", I'm gonna go with his explanation. :-)

>     I'm guessing that the actual mathematical formalism that we have for 
> QM addresses all that is _needed_, in that it always works, and we know 
> of no phenomenon (except perhaps gravity) that our mathematical 
> formalism fails at. 

The other quantum stuff is similar but not identcail formulas, yes.

> Given that, having an argument about whether it's a 
> wave or a particle is philosophy of the pointless kind. The theory will 
> remain unchanged.

Yep.

> any of you has bothered to *define* what a particle is or what a wave 
> is. 

Well, I tried to indirectly describe things a wave would do that a particle 
doesn't, but yeah.

> We had an illusion that we understood that better merely 
> because we were used to it in our daily lives. But that's just an illusion.

True. It's like asking *why* there are three dimensions, or *why* you 
subtract the square of time instead of adding it in GR.

>     In general, are you sure polarization cannot be described just by 
> waves? If you have waves in 3-D materials? FYI, the standard model for 
> sound waves in solids (i.e. phonons) assumes they have a polarization.

I think the effect of polarization of quanta does stuff that polarization 
based entirely on the directions of waves can't do, like lasing and fermion 
exclusion.

>     I haven't read the book, but my physics professor said that it's THE 
> book to read (QED) if you want to get an understanding of light/EM 
> phenomenon.

Yep. It's awesome, explained by the guy who invented the way to calculate 
the stuff *based* on the explanation. The link to the videos is Feynman 
presenting the lectures that got edited into the book, which is also 
fascinating.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Darren New wrote:
> In other words, if it takes an "observer" to collapse the wave function, 
> is the cat enough of an "observer" to count? If so, how does the human 
> get involved? According to the math, the cat is still superimposed. But 
> that would imply the cat isn't sufficiently an observer to cause the 
> collapse. *Or* that the math doesn't match reality. And multi-worlds is 
> an attempt to say "no, the math really matches reality."
> 

One tends to suspect that, as a thought experiment, it runs into the 
same problem as Zeno's Paradox. Which is to say, there is some specific 
minimum interaction/time frame/minimal distance, or what ever, in which 
something either does *or* doesn't happen, and you can't have it be both 
at the same time. In Zeno's case, there is literally a very small, but 
provable, distance that you *must* move, if you move at all, and 
crossing that line eliminates the paradox (in this case, probably 
something like the closest you can get to another particle, without it 
nudging the other particle, or something to that effect). They have 
already proven, using QM experiments, that they *is* such a limit with 
time, and that *before* that point you can nudge a particle back into 
what ever state it had prior to measurement, but, anything after that 
you are stuck with what ever the prior interaction gave you. The 
previous assumption was that such events where instantaneous, and no 
such micro-time event was possible.

Thus, the thought experiment is flawed, unless, as I said, you assume 
that the entire box, everything in it, and thus what it does, is all 
*one* object. A classic case of, "Of course a tree makes a sound if it 
falls in an empty forest with no one to see it." The flaw is the 
assumption that *someone* has to look into the box. I am not sure how to 
put it.. Basically, its like astrology. Imagining that just because a 
lot of big stuff is wandering around the universe, the small stuff 
**must** be so drastically influenced by it that a cat can actually *be* 
in such an indeterminate state. Not so. Either *any* interacting causes 
a state change, in which case the cat *must* be in a known state 
already, or nothing is, including the poor deluded fool worrying about 
whether or not he killed the neighbors cat in the experiment, in which 
case we might as well start talking to priest and gurus about 
transcendentalism, and give up on physics.

Yeah, there are some goofy theories that sort of allow for it, but most 
of them are notable in that they have to do things like throwing out 
time, without having any damn math, never mind real theory, about how to 
replace it with something that still *acts* like time from our view. Its 
one thing to propose a thought experiment, its another to invent an 
entire branch of, "this will fill in all the holes, I promise", 
'science', which consists of no concrete data, experiments, theories, or 
plausible mechanisms, and amounts to nothing *but* a long list of 
thought experiments.

People tried that once before. It was called Alchemy, and, within its 
own, flawed and incorrect, framework, everything known at the time 
"worked" by its rules, including the math involved. It would be nice of 
we at least tried to stick with dealing with the universe we can 
observe, instead of wandering off into 50,000 of them we can't, trying 
to find some weird sort of universe that would **look like** ours, if 
stuck inside it. Not even string theory gets that odd, most of the time, 
and it, so far, is about as useful at explaining anything as staring at 
a something like the "accidental isosuface" thread is *actually* an 
accurate method of predicting planet formation.

It might lead some place, maybe. At the moment, even some of the people 
that wanted it to lead some place are looking at those studying the math 
and thinking, "Ok, so... when are we going to get a theory, never mind 
actual useful data, out of this 'science'?" lol

-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

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On 12/02/09 22:15, Darren New wrote:
> I'm just stating my understanding of the general consensus. I freely

	The only real consensus is on the mathematical formalism. It wouldn't 
surprise me if most physicists I've interacted would either say "acts 
like both a particle or a wave, so it's both" or simply say "it's 
neither, and don't waste time thinking about it".

	Take the two Nobel laureates here:

"The 29 December 2005 edition of the International Herald Tribune 
printed an article, "New tests of Einstein's 'spooky' reality", which 
referred to Leggett's Autumn 2005 debate at a conference in Berkeley, 
California, with fellow Nobel laureate Norman Ramsey of Harvard 
University.[5] Both debated the worth of attempts to change quantum 
theory. Leggett thought attempts were justified, Ramsey opposed. Leggett 
believes quantum mechanics may be incomplete because of the quantum 
measurement problem."

	(From Leggett's Wikipedia page). His stance is interesting, as there 
was another well known physicist (not a Nobel Laureate, but a member of 
the NAS nevertheless) who argued that the derivation of the Bell's 
Inequalities used arguments/theorems from statistics which, while 
correct, were more limited in scope than most physicists think, and he 
believed it wasn't sufficient enough to completely counter the notion of 
hidden variables.

	The "interesting" thing was that Leggett, who himself has issues with 
the whole quantum measurement problem, thought this third guy was a 
quack (on this topic, not as a physicist as a whole).

	Physicists _do_ disagree. They probably only agree that it's 
irrelevant.<G>

> admit that maybe they're wrong, but when the guy who got the nobel prize
> for explaining to other theoretical pysicists how it works says "It's
> never ever a wave", I'm gonna go with his explanation. :-)

	Well, sure. And I don't doubt that many physicists including Nobel 
Laureates disagree. And they're free to, because it is now in the realm 
of philosophy. The theory won't change either way. I don't think any one 
so far has come up with a "Well if we could show that it's REALLY a 
wave/particle (whatever that means), then we'd have this phenomenon that 
QM doesn't already predict".

	I guess I mean to say that I doubt you can scientifically demonstrate 
(i.e. with repeatable experiments) that it is truly a particle or truly 
a wave or truly both. And if you did, I bet that you merely defined 
particle/wave/both to be whatever the outcome of the experiment is.

>> We had an illusion that we understood that better merely because we
>> were used to it in our daily lives. But that's just an illusion.
>
> True. It's like asking *why* there are three dimensions, or *why* you
> subtract the square of time instead of adding it in GR.

	Precisely.

>> In general, are you sure polarization cannot be described just by
>> waves? If you have waves in 3-D materials? FYI, the standard model for
>> sound waves in solids (i.e. phonons) assumes they have a polarization.
>
> I think the effect of polarization of quanta does stuff that
> polarization based entirely on the directions of waves can't do, like
> lasing and fermion exclusion.

	Except that there's nothing fundamental in physics that doesn't allow 
lasing with phonons instead of photons. God simply didn't give us solids 
with the proper material properties that would allow it easily, and no 
one has figured out a way to engineer such solids. See

http://en.wikipedia.org/wiki/Sound_Amplification_by_Stimulated_Emission_of_Radiation

	The theory of phonons is almost identical to that of photons. Discrete, 
energy packets of energy h*f, that can be absorbed/emitted by particles 
like electrons. The math is quite similar. It's just that photons are 
fundamental particles, and phonons, well, don't seem to be. They're just 
atomic/ionic vibrations in a crystal lattice, and some kinds of phonons 
are responsible for sound in solids.

	Don't know what you mean by fermion exclusion. Maybe it was in another 
message. You mean as in the Pauli exclusion? If so, I was referring to 
photons and making the analogy, where Pauli exclusion doesn't apply.

PS - Apparently some people did claim to produce a phonon laser a few 
months ago. I should try to see if I can make any sense of their paper...

http://today.caltech.edu/today/story-display-blurb?story_id=38363

-- 
Americans are getting stronger. Twenty years ago, it took two people to 
carry ten dollars' worth of groceries. Today, a five-year-old can do it.

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Patrick Elliott wrote:
> Either *any* interacting causes 
> a state change, in which case the cat *must* be in a known state 
> already, or nothing is, including the poor deluded fool worrying about 
> whether or not he killed the neighbors cat in the experiment, 

Except that's exactly the point. The math says it's the latter case. And the 
cat experiment is to point out how absurd that conclusion is. Hence, the 
math must be mistaken.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New <dne### [at] sanrrcom> wrote:
> As I said, the probability of finding a particle in a particular place is 
> based on multiplying complex numbers.

  Btw, I find it curious how you use the mathematical models as some kind
of evidence that photons are not waves. After all, Feynman himself stressed
that his formulation is merely a mathematical description, not an attempt to
describe a real process that we cannot meassure.

-- 
                                                          - Warp

Post a reply to this message

Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> >   Schrodinger's cat is a thought experiment, not an analogy.

> It's not even that hard to set up. :-)

> I think the point is that you have to question what an "observation" is. If 
> the particle gets emitted and runs into the detector when the power is 
> turned off, is it "observed"?  If the power is on but the detector isn't 
> connected to anything?  If it's connected to a speaker you can't hear? If 
> it's connected to poison but there's no cat in the box?  Etc?

> In other words, if it takes an "observer" to collapse the wave function, is 
> the cat enough of an "observer" to count? If so, how does the human get 
> involved? According to the math, the cat is still superimposed. But that 
> would imply the cat isn't sufficiently an observer to cause the collapse. 
> *Or* that the math doesn't match reality. And multi-worlds is an attempt to 
> say "no, the math really matches reality."

  AFAIK those are the things Erwin Schr?dinger questioned about the
Copenhagen interpretation with his now-famous thought experiment.

-- 
                                                          - Warp

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> As I said, the probability of finding a particle in a particular place is 
>> based on multiplying complex numbers.
> 
>   Btw, I find it curious how you use the mathematical models as some kind
> of evidence that photons are not waves.

I believe you misunderstand me. I'm saying we never observe a wave. We just 
observe math that's the same math as a wave. That isn't what makes it "not a 
wave", that's what makes people used to think (and some people still think) 
it was a wave. :-)

I.e., just the opposite. The mathematical model is *not* evidence it's a 
wave, any more than the interference patterns are.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
>   AFAIK those are the things Erwin Schr?dinger questioned about the
> Copenhagen interpretation with his now-famous thought experiment.

Yes. I'm agreeing with you, and hopefully adding some more to the discussion.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New <dne### [at] sanrrcom> wrote:
> I.e., just the opposite. The mathematical model is *not* evidence it's a 
> wave, any more than the interference patterns are.

  I don't really know your definition of "evidence", but as I understand it,
the interference pattern *is* evidence for it to be wave. It's not *proof* of
it, but evidence is no proof anyways.

-- 
                                                          - Warp

Post a reply to this message

> Except that's exactly the point. The math says it's the latter case. And 
> the cat experiment is to point out how absurd that conclusion is. Hence, 
> the math must be mistaken.

What happens if you shut the double-slit experiment away in a box, with 
photon detector attached to each slit?  Will the interference pattern still 
be generated?

Post a reply to this message

scott wrote:
>> Except that's exactly the point. The math says it's the latter case. 
>> And the cat experiment is to point out how absurd that conclusion is. 
>> Hence, the math must be mistaken.
> 
> What happens if you shut the double-slit experiment away in a box, with 
> photon detector attached to each slit?  Will the interference pattern 
> still be generated?

No.  Worse, check out this:

http://en.wikipedia.org/wiki/Wheeler%27s_delayed_choice_experiment

Basically, the photon behaves differently even if you measure it *after* it 
has passed through the slits. Which is why it's pretty safe to assume it's 
not "going thru both slits" when you get the interference pattern.

http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

This one changes whether the photon went thru one or both slits *after* it 
has already been detected. Hard to see how that's the behavior of a wave 
that passes through both slits.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

>> What happens if you shut the double-slit experiment away in a box, with 
>> photon detector attached to each slit?  Will the interference pattern 
>> still be generated?
>
> No.  Worse, check out this:
>
> http://en.wikipedia.org/wiki/Wheeler%27s_delayed_choice_experiment
>
> Basically, the photon behaves differently even if you measure it *after* 
> it has passed through the slits. Which is why it's pretty safe to assume 
> it's not "going thru both slits" when you get the interference pattern.

But put the whole thing inside a big closed box so nobody can observe the 
patterns (exactly like the cat in a box setup).  If a cat's status is not 
decided until someone looks inside (even though there is a particle detector 
and related mechanisms inside) then why should the interference pattern not 
be there if nobody is observing it?

Post a reply to this message

scott wrote:
> If a cat's status is not decided until someone looks inside 

Since that isn't true, it's a meaningless question to ask.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

>> If a cat's status is not decided until someone looks inside
>
> Since that isn't true, it's a meaningless question to ask.

I thought the whole point of that experiment was that according to QM the 
cat was both alive and dead until you actually tried to look?  Maybe 
something changed since I read about it?

Post a reply to this message

scott wrote:
>>> If a cat's status is not decided until someone looks inside
>>
>> Since that isn't true, it's a meaningless question to ask.
> 
> I thought the whole point of that experiment was that according to QM 
> the cat was both alive and dead until you actually tried to look?

That's correct. But it's clearly not true, because the *cat* is observing 
the situation, right? Of course the cat's status is decided by the cat 
before anyone looks in the box, and thus there must be something wrong with 
the concept that states remain in superposition until "observed." The point 
was to ask "how observed does it need to be?"

I.e., the whole point of the experiment is to show how absurd it was to 
think the QM "collapsed because it's observed" promoters were right.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New wrote:
> scott wrote:
>>>> If a cat's status is not decided until someone looks inside
>>>
>>> Since that isn't true, it's a meaningless question to ask.
>>
>> I thought the whole point of that experiment was that according to QM 
>> the cat was both alive and dead until you actually tried to look?
> 
> That's correct. But it's clearly not true, because the *cat* is 
> observing the situation, right? Of course the cat's status is decided by 
> the cat before anyone looks in the box, 

Who on Earth would let a cat decide anything? One whiff of catnip and it 
would say whatever you wanted. ;)
> 
> I.e., the whole point of the experiment is to show how absurd it was to 
> think the QM "collapsed because it's observed" promoters were right.
> 

That’s what I thought too.

-- 

Best Regards,
	Stephen

Post a reply to this message

scott <sco### [at] scottcom> wrote:
> I thought the whole point of that experiment was that according to QM the 
> cat was both alive and dead until you actually tried to look?

  Not according to QM. According to the Copenhagen interpretation of it.

-- 
                                                          - Warp

Post a reply to this message

Darren New <dne### [at] sanrrcom> wrote:
> I.e., the whole point of the experiment is to show how absurd it was to 
> think the QM "collapsed because it's observed" promoters were right.

  That might have been the point of the experiment, but did it cause the
Copenhagen interpretation to be ditched, or is it still a "we don't know
for sure"?

-- 
                                                          - Warp

Post a reply to this message

Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> I.e., the whole point of the experiment is to show how absurd it was to 
>> think the QM "collapsed because it's observed" promoters were right.
> 
>   That might have been the point of the experiment, but did it cause the
> Copenhagen interpretation to be ditched, or is it still a "we don't know
> for sure"?

As far as I know, they're still trying to figure out *why* the math works 
like it does. Neeum posted this, which (after the Bell Inequality stuff at 
the start indicating a need to consider this in the first place) discusses 
the different possible view on the "why" of it all...

http://www.karlin.mff.cuni.cz/~motl/entan-interpret.pdf

Overall, I think some people are saying "if you're careful with the math, 
it's obvious why it 'collapses'" but others obviously aren't so sure. Half 
the people looking at the copenhagen interpretation think the wave is real 
and half think it's just a way of looking at it mathematically, even so.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
> scott <sco### [at] scottcom> wrote:
>> I thought the whole point of that experiment was that according to QM 
the 
>> cat was both alive and dead until you actually tried to look?
> 
>   Not according to QM. According to the Copenhagen interpretation of it
.

More technically, according to the math of the Schrödinger equation,
 which 
has no allowance for any non-QM events inside it. I.e., the math of QM 
doesn't anywhere say "and at this point, you get quantum collapse." It's 

trying to figure out why you *do* get quantum collapse that's the problem
.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

On Mon, 07 Dec 2009 08:27:20 -0800, Darren New wrote:

> But it's clearly not true, because the *cat* is observing the situation,
> right?

Only if the cat's alive.... ;-)

Jim

Post a reply to this message

Stephen wrote:
>> I.e., the whole point of the experiment is to show how absurd it was 
>> to think the QM "collapsed because it's observed" promoters were right.
>>
> 
> That’s what I thought too.
> 

Of course, the only flaw in the argument is that a cat isn't a particle, 
so what effects *one* particle, doesn't effect something made of a *lot* 
of them. This is the absurdity involved. Its like asking why relativity 
doesn't work in black holes. Because its a bloody black hole, which has 
different rules. In effect, QM is what goes on in single instances, 
normal reality is an emergent property of what happens when QM can't 
(or, if you prefer, the constraints put on the system reduce the 
probability of a different result to near zero). Sort of like those 
strange attractor images. Without the attractor, you don't get an image, 
add one in, and the system gains constraints it didn't have before. Same 
with particle interactions. Right?

-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models, 
3D Content, and 3D Software at DAZ3D!</A>

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Patrick Elliott wrote:
> Of course, the only flaw in the argument is that a cat isn't a particle, 
> so what effects *one* particle, doesn't effect something made of a *lot* 
> of them. 

Why not?  Indeed, that *is* the flaw in the argument, but the question is 
"why not?"

> This is the absurdity involved. Its like asking why relativity 
> doesn't work in black holes. Because its a bloody black hole, which has 
> different rules. 

Relativity works just fine in black holes. That's why we know about them.

> In effect, QM is what goes on in single instances, 

Single instances of what?

> normal reality is an emergent property of what happens when QM can't 
> (or, if you prefer, the constraints put on the system reduce the 
> probability of a different result to near zero).

Like what, in the case of the cat, specifically?  A different result from 
being alive or dead?

> Same with particle interactions. Right?

You tell me. You seem to have it all figured out so trivially.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New wrote:
> Warp wrote:
>>   Schrodinger's cat is a thought experiment, not an analogy.
> 
> It's not even that hard to set up. :-)

I beg to differ -- AFAIK it's unbelievably difficult to put a box the 
size of a cat into complete quantum isolation with the rest of a room.

Post a reply to this message

scott wrote:
>>> If a cat's status is not decided until someone looks inside
>>
>> Since that isn't true, it's a meaningless question to ask.
> 
> I thought the whole point of that experiment was that according to QM 
> the cat was both alive and dead until you actually tried to look?  Maybe 
> something changed since I read about it?


To be clear, strictly speaking this is not "according to QM" but rather 
according to the Copenhagen Interpretation of QM (which is currently the 
most popular interpretation of the mathematics).

Post a reply to this message

Kevin Wampler wrote:
> scott wrote:
>>>> If a cat's status is not decided until someone looks inside
>>>
>>> Since that isn't true, it's a meaningless question to ask.
>>
>> I thought the whole point of that experiment was that according to QM 

>> the cat was both alive and dead until you actually tried to look?  
>> Maybe something changed since I read about it?
> 
> 
> To be clear, strictly speaking this is not "according to QM" but rather
 
> according to the Copenhagen Interpretation of QM (which is currently th
e 
> most popular interpretation of the mathematics).

I thought it was "according to the Schrödinger's wave equations"?

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New wrote:
>>> I thought the whole point of that experiment was that according to QM 
>>> the cat was both alive and dead until you actually tried to look?  
>>> Maybe something changed since I read about it?
>>
>>
>> To be clear, strictly speaking this is not "according to QM" but 
>> rather according to the Copenhagen Interpretation of QM (which is 
>> currently the most popular interpretation of the mathematics).
> 
> I thought it was "according to the Schrödinger's wave equations"?


I should have checked to see that Warp had already written the same 
thing I had, oh well.

At any rate, the relevant part of the wave equations here is really the 
fact that they describe the probabilities of the outcomes of 
measurements.  In terms of "what's actually going on" any explanation 
which can reproduce these probabilities is on equal footing WRT the 
equations, and stating that the cat in superposition before measurement 
and "collapses" when we open the box is only one such possible explanation.

Granted, it's worth noting (as you're aware) that the nature of QM puts 
some pretty severe restrictions on what sorts of explanations can match 
the observed measurements, but it's not as if the Copenhagen 
Interpretation is the only possibility: 
http://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics

Post a reply to this message

Kevin Wampler wrote:
> At any rate, the relevant part of the wave equations here is really the 
> fact that they describe the probabilities of the outcomes of 
> measurements.  

Right. And the question is "what's a measurement" in this case. That's the 
outstanding question.  Since measuring a superimposed state can give you an 
answer different from any possible "outcome" per se, figuring out when a 
"measurement" has occurred is the problem.

> and stating that the cat in superposition before measurement 
> and "collapses" when we open the box is only one such possible explanation.

For us, maybe. Not for the cat.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
>   If it looks like a wave, feels like a wave, smells like a wave, what is it?
> Not a wave, it seems. It just fakes being one quite well.

In general I agree with Neeum that it's not meaningful to discuss 
weather it's a "wave" without defining what you even mean by a wave, but 
I still thought I'd point out one way in which the "waves" in QM behave 
differently from classical waves.

This was mentioned by Feynman in the short video linked by Darren, and 
it's that in multiple particle systems the wave function doesn't just 
describe the probability of finding a single particle at a given 
position, but rather the probability of finding the entire system of 
particles in a given configuration.  This is distinct from the way that 
classical waves behave, and is the source of effects of "non locality" 
in quantum systems which would not arise from a system with classical waves.

If you want to still call this a wave (perhaps a wave in the 
configuration space of the system?) then that's clearly fine, but it's 
worth keeping in mind that it's a different sort of wave than one 
generally means in classical systems.

Post a reply to this message

Darren New wrote:
> Kevin Wampler wrote:
>> At any rate, the relevant part of the wave equations here is really 
>> the fact that they describe the probabilities of the outcomes of 
>> measurements.  
> 
> Right. And the question is "what's a measurement" in this case. That's 
> the outstanding question.  Since measuring a superimposed state can give 
> you an answer different from any possible "outcome" per se, figuring out 
> when a "measurement" has occurred is the problem.

Exactly why I phrased my sentence the way I did.  The Schrödinger 
equations don't directly say anything about what state the cat's in, or 
even if it's in a deterministic state or not -- it's how you treat the 
process of measurement that does, and that's a philosophical questions 
rather than a scientific one at this point (and thus not part of QM 
proper but of its interpretation).

More specifically, AFAIK there are some interpretations of QM which give 
the cat a deterministic state, and others which don't (and I assume 
others which regard the question as meaningless).  All are in agreement 
with he Schrödinger wave equation, so it's not the equation that's the 
issue here.


>> and stating that the cat in superposition before measurement and 
>> "collapses" when we open the box is only one such possible explanation.
> 
> For us, maybe. Not for the cat.

Indeed, but I don't understand what this has to do with the Schrödinger 
equations, since it seems (as I mentioned) to be only a problem with the 
Copenhagen interpretation.  Perhaps I'm missing what point you're making?

Post a reply to this message

Kevin Wampler wrote:
> If you want to still call this a wave (perhaps a wave in the 
> configuration space of the system?) then that's clearly fine, but it's 
> worth keeping in mind that it's a different sort of wave than one 
> generally means in classical systems.

I think that's really the problem. When I say "it's not a wave", I'm saying 
you don't get any of the same measurements from one particle that you'd get 
from a wave. There's some wave-like stuff going on, but not in a way that 
you'd normally say the photon *is* a wave.


For more fun confusion, what does multi-world say about stuff?

http://en.wikipedia.org/wiki/Quantum_suicide_and_immortality

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Kevin Wampler wrote:
> All are in agreement 
> with he Schrödinger wave equation, so it's not the equation that's
 the 
> issue here.

OK. I'm now more educated, I think.

> Indeed, but I don't understand what this has to do with the Schröd
inger 
> equations, since it seems (as I mentioned) to be only a problem with th
e 
> Copenhagen interpretation.  Perhaps I'm missing what point you're makin
g?

Only that the quantum equations don't *seem* to apply to the macroscopic 

world, for reasons unknown?

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New wrote:
> Kevin Wampler wrote:
>> All are in agreement with he Schrödinger wave equation, so it's not 
>> the equation that's the issue here.
> 
> OK. I'm now more educated, I think.

It's a point which is often neglected.  Just to be clear though, the 
issue is more subtle than I'm making it sound and AFAIK most 
interpretations which give a deterministic state to the cat have run 
into problems (for instance when incorporating them into special 
relativity).  Also such interpretations are necessarily non-local.


>> Perhaps I'm missing what  point you're making?
> 
> Only that the quantum equations don't *seem* to apply to the macroscopic 
> world, for reasons unknown?

Yeah, IANAP (I am not a physicist) but as far as I'm aware this is 
correct.  Although I think there's some interpretations which describe 
why this is the case perfectly well, they just might come with other 
philosophical implications that are undesirable (for instance I'd put 
the many-worlds interpretation into this class).

Post a reply to this message

Kevin Wampler wrote:
> Also such interpretations are necessarily non-local.

I read recently that someone did a Bell's Inequality type of experiment with 
  more than 20 angles measured in 3D and from that somehow deduced locality. 
Interesting.

> Yeah, IANAP (I am not a physicist) but as far as I'm aware this is 
> correct.  Although I think there's some interpretations which describe 
> why this is the case perfectly well, they just might come with other 
> philosophical implications that are undesirable (for instance I'd put 
> the many-worlds interpretation into this class).

Yah. I suspect it's much more mundane, like the "decoherence" section of the 
paper Neeum posted.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Darren New wrote:
> Kevin Wampler wrote:
>> Also such interpretations are necessarily non-local.
> 
> I read recently that someone did a Bell's Inequality type of experiment 
> with  more than 20 angles measured in 3D and from that somehow deduced 
> locality. Interesting.

Do you have a reference to this?  I'd be interested to see the details 
of what exactly they mean by that.

Post a reply to this message

Kevin Wampler wrote:
> Do you have a reference to this?  I'd be interested to see the details 
> of what exactly they mean by that.

I'm afraid that was before I started bookmarking everything that caught my 
interest. :-)  It was in something like Discover magazine, so there wasn't 
much detail beyond what I already said in the article itself, but there 
might have been links to the actual publication on the page.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

Invisible wrote:
> http://en.wikipedia.org/wiki/File:Perseid_Meteor.jpg
> 
> Here in the name of God does the night sky actually look like this?!

Anywhere far away from any major population center.  In addition to 
being able to see many more stars, I've found that you can also spot 
about 10-30 shooting stars per hour in areas like that.  It's quite 
beautiful, and unfortunate that many people have always lived where you 
simply can't see that sort of thing.

Post a reply to this message

Darren New wrote:
> Patrick Elliott wrote:
>> Of course, the only flaw in the argument is that a cat isn't a 
>> particle, so what effects *one* particle, doesn't effect something 
>> made of a *lot* of them. 
> 
> Why not?  Indeed, that *is* the flaw in the argument, but the question 
> is "why not?"
> 
>> This is the absurdity involved. Its like asking why relativity doesn't 
>> work in black holes. Because its a bloody black hole, which has 
>> different rules. 
> 
> Relativity works just fine in black holes. That's why we know about them.
> 
>> In effect, QM is what goes on in single instances, 
> 
> Single instances of what?
> 
>> normal reality is an emergent property of what happens when QM can't 
>> (or, if you prefer, the constraints put on the system reduce the 
>> probability of a different result to near zero).
> 
> Like what, in the case of the cat, specifically?  A different result 
> from being alive or dead?
> 
>> Same with particle interactions. Right?
> 
> You tell me. You seem to have it all figured out so trivially.
> 
No, what I am getting at is the math works in some specific cases, but 
most of the time your particles are "not" in a state where that case 
applies. That is what I mean about constraints. The cat, as a 
collection, has constraints that an individual particle, in the test 
cases, doesn't. After all, we don't throw cats are targets to measure 
their QM, we generate single particles. And, no, that isn't bloody 
trivial, any more than saying, "adding a strange attractor", tell you 
what the result will actually look like. It just tells you it won't be 
what you would have had *without it*. If I said A + B = QM, that would 
be a "trivial" solution. lol

-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models, 
3D Content, and 3D Software at DAZ3D!</A>

Post a reply to this message

Patrick Elliott wrote:
> No, what I am getting at is the math works in some specific cases, but 

> most of the time your particles are "not" in a state where that case 
> applies. 

Why not? If the particle gets in that state, how does it get out of that 

state? You can't just say "interaction" without giving specifics, since 
"interaction with other particles" is exactly what QM defines. If it was 

obvious that mere interactions with other particles resolved the problem,
 
the guy who invented the Schrödinger equations wouldn't have come up
 with 
the thought experiment in the first place.

What situations do particles get into where the QM equations don't apply?
 
Because every test seems to indicate we know the right *equations* to a 
tremendous number of decimal places.  You can't just say "it doesn't appl
y 
sometimes" without saying the circumstances under which it doesn't.

> That is what I mean about constraints. The cat, as a 
> collection, has constraints that an individual particle, in the test 
> cases, doesn't. 

That's the "decoherence" argument, if I understand you right. It's one of
 
many possible answers, but it's not obviously accepted by everyone involv
ed.

What constraint applies to many particles that doesn't apply to one, 
according the the Schrödinger equations?

> After all, we don't throw cats are targets to measure 
> their QM, we generate single particles. 

Sure. But we look at distant stars to see the QM manifest in outer space.
 We 
generate Bose-einstein condensates bigger than a cat.

> It just tells you it won't be 
> what you would have had *without it*. 

Sorry. Pronoun overflow. What tells me what what wont be without what?


-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Darren New wrote:
>> It just tells you it won't be what you would have had *without it*. 
> 
> Sorry. Pronoun overflow. What tells me what what wont be without what?
> 

What the result will be, without an attractor. As I said, I don't have a 
math equation to explain it, but there obviously needs to be one, since, 
under normal circumstances, as you say, you don't get non-decoherent 
effects.


-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

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3D Content, and 3D Software at DAZ3D!</A>

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Patrick Elliott wrote:
> What the result will be, without an attractor. 

OK, I'm afraid you're not making any sense to me, so ... nevermind.

You're either completely missing my point, or you're talking about something 
entirely different than what I am.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Darren New wrote:
> Patrick Elliott wrote:
>> What the result will be, without an attractor. 
> 
> OK, I'm afraid you're not making any sense to me, so ... nevermind.
> 
> You're either completely missing my point, or you're talking about 
> something entirely different than what I am.
> 
I am saying that, in general principle, large masses of particles act 
"similar" to what a strange attractor does for the images some people 
have been making in povray.images. It changes the behavior of the 
system. Until you plot the result, you don't necessarily have a 
prediction of what that will be, but it "not" what you end up with if 
you had one single particle. Mind, in reality, we have fairly clear 
ideas what happens if you place x number of protons/neutrons and 
electrons together, in a stable configuration, you end up with an 
element or isotope.

None of which describes why, or how, trivially or otherwise, which is 
the crux of your accusation.

-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models, 
3D Content, and 3D Software at DAZ3D!</A>

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