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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 12:51:56
Message: <4844252c@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> For example, there's no known mathematical model to indicate where a 
>> specific electron is, and indeed if I understand correctly, experiments 
>> show there cannot be one.
> 
>   That's a bit like being in the middle of the ocean and saying "there's
> no mathematical model which says where the water is", speaking as if the
> "water" was a point in space and you'd had to locate it at some specific
> coordinates.
> 
>   Your statement is like that. You are starting from the assumption that
> an electron is an extremely small particle with well-defined boundaries,
> approximately equal to a mathematical point, and then you ask for a
> mathematical model to say where that point is in space. As with the
> water example, that's kind of silly.

I guess I was kind of sloppy. I was saying that there's no mathematical 
model that tells you where you will find a specific electron when you 
look for it in a set of places. E.g., if you shoot an electron at a 
flourescent screen, there's no model (and *can* be no model) that tells 
you where on the screen that electron will hit.

>   What the mathematical model *can* do is to give a distribution function
> which tells how the electron is distributed in space (a bit like a
> function which tells how the water is distributed, except that with
> the electron the "density" of the "water" is not constant).

No, actually, it tells you the likelihood of finding it at any 
particular place, were you to look.

There's another distribution function that tells you the likelihood it's 
in a particular place if you *don't* look.

When you put those two together, you get the two-slit experiment.

>   It's not like you could shoot an electron to some direction, and then
> the electron suddenly hits the other side of the Earth (or the solar
> system). It hits a quite accurately calculable place.

No, it doesn't. The probability of hitting anywhere in particular is an 
infinite sum of complex (as in, real+imaginary) probabilities.

Yes, it can actually hit the other side of the Earth. It can also hit a 
week before you shoot it. Very unlikely, but possible.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 12:53:29
Message: <48442589@news.povray.org>
John VanSickle wrote:
> I wouldn't say that it is truly random, but merely that predicting the 
> outcome of any interaction requires information that is presently not 
> available.

You would be incorrect. Google on "Bell's Inequality".

> For instance, the decay of unstable particles appears to happen 
> randomly, but at what appears to be a predictable rate for aggregate 
> amounts of like particles.  What is likely is that the particles decay 
> when they encounter certain conditions (such as a gradient in the 
> electric or magnetic potential) that is high enough to overcome the weak 
> internal cohesiveness of the particle, causing it to come apart. 

That's the "hidden variable" theory. It has been disproven, multiple 
times and with hundreds of different experiments. Boggling, isn't it?

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 12:54:42
Message: <484425d2@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> No, it only interferes with other electrons. The electrons it interferes 
> with are electrons from other times. There's always a possibility that 
> it lands at any particular place. Why is it any stranger that it 
> interferes with electrons in the future than it is it interferes with 
> itself?

  Because time travel doesn't exist?

-- 
                                                          - Warp


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 13:02:20
Message: <4844279c$1@news.povray.org>
Mueen Nawaz wrote:
>     There's the whole issue of "renormalization" to deal with infinities 
> in physics. I won't go into any detail as I've never formally studied 
> it. But it's another often cited example of "fishy mathematics".

I understand it enough to explain informally. When you're calculating 
the probability of an event, you have to take into account every way 
that event could occur, and add them up. So maybe the photon leaves the 
candle and hits the film. Or it leaves the candle, splits into an 
electron and positron, which then later recombine into a photon, which 
hits the screen. Or it splits into an electron and positron, and the 
positron goes off to the Sun back in time to combine with an electron 
there, which makes it turn into a photon which happens to come back to 
Earth which strikes the electron which pushes it into the wall which 
emits a photon which hits the film. And so on.

So basically, you're adding up more and more events of lower and lower 
probability. And it turns out that if you add them all up, you get 
infinite probability everywhere.

But if you stop at, say, 10^-50 probability, and then renormalize 
(something like divide by 10^-50), you get a number. And if you stop at 
10^-60 and then renormalize (something like divide by 10^-60), you get 
the same number. As long as you renormalize to where you stopped, you 
get the same number. But nobody knows why you have to stop, and there's 
so far no physical reasoning as to where you have to stop.

Speculation is that space is actually quantum, so the mathematics of 
"real numbers" breaks down because they can get smaller than reality. 
Which is where the Plank's constant seems to come in - speculation that 
it's describing the quantum of size.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 13:03:13
Message: <484427d0@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> >   So when the electron hits the sensitive film *after* it has passed the
> > slits, it goes back to the past and changes it so that it goes through
> > only one of the slits after all?

> No. It either interferes with itself or not. You're assuming the only 
> way it can interfere with itself is to go through both slits. There's no 
> evidence that's the case, and much evidence that it isn't.

  So why does it interfere with itself when there are two slits but not
when there is only one? If it was just one regular physical macroscopical
particle it wouldn't matter how many slits there are: If it goes through
one of them, it just goes through one of them, that's it. It doesn't even
"know" that there are other slits.
  However, when there are two slits, the electron passes through and starts
interfering with itself, as if it has passed through both and changed
direction in different ways.

  How else can this be explained? How does the electron "know" that there's
another slit so that it "knows" to start interfering with itself, other than
actually going through the other slit as well?

  (I believe this has something to do with wave-particle duality: In the
double-slit experiment the wave nature of the electron shows up: The wave
goes through both slits and starts interfering with itself.)

> >   So you are saying that, even though the only possible explanation for
> > interference patterns is that the electron passed through both slits,
> > there's still no evidence of that?

> Yes. What makes you think that the only *possible* explanation is that 
> the electron passed through both slits?

  What is the other explanation?

> >   If there's "no evidence", what do you call the interference pattern?
> > "Non-evidence"?

> Interference.

  The interference can be explained with the electron passing through both
slits at the same time. Ergo the interference is evidence of that happening.
(Note that "evidence" is not the same thing as "proof".)

-- 
                                                          - Warp


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 13:03:22
Message: <484427da@news.povray.org>
Warp wrote:
>   Your statement is like that. You are starting from the assumption that
> an electron is an extremely small particle with well-defined boundaries,

By the way, this is why it's called "quantum" physics. :-) Because it's 
*not* a wave - there *is* a well-defined particle in a particular place.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 13:07:32
Message: <484428d4@news.povray.org>
Mueen Nawaz <m.n### [at] ieeeorg> wrote:
> Warp wrote:
> >   It's not like you could shoot an electron to some direction, and then
> > the electron suddenly hits the other side of the Earth (or the solar
> > system). It hits a quite accurately calculable place.

>         There is a non-zero probability that this can happen.

  I bet the probability is so small that it hits the barrier of some
physical constant (Planck maybe?)

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 13:12:54
Message: <48442a15@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> >   What the mathematical model *can* do is to give a distribution function
> > which tells how the electron is distributed in space (a bit like a
> > function which tells how the water is distributed, except that with
> > the electron the "density" of the "water" is not constant).

> No, actually, it tells you the likelihood of finding it at any 
> particular place, were you to look.

  Assuming the particle *is* at some specific location at any given time
instead of being distributed in space.

> Yes, it can actually hit the other side of the Earth. It can also hit a 
> week before you shoot it. Very unlikely, but possible.

  I don't believe in the time travelling. As for the location, I assume
the probability of it hitting the other side of the Earth is so small that
some physical constant prevents it.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 13:17:59
Message: <48442b46@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> >   Your statement is like that. You are starting from the assumption that
> > an electron is an extremely small particle with well-defined boundaries,

> By the way, this is why it's called "quantum" physics. :-) Because it's 
> *not* a wave - there *is* a well-defined particle in a particular place.

  Actually "quantum physics" means that everything is quantified. That is,
there's a minimum amount of everything (for example electric charge and
mass), and everything is an integer multiple of that amount. You just can't
have eg. half of the electric charge of an electron, for example.

  Waves are also quantified for the same reason: There's a minimum amount
of amplitude, for example, and all amplitudes are integer multiples of
that amount.

  These "quants" behave oddly. Sometimes they behave like particles,
sometimes they behave like waves, and sometimes they behave like both
at the same time. Different measurements of the exact same quant can
show wildly different behavior in this respect. (One experiment will
clearly show that light behaves like a wave and not like a stream of
particles, while another experiment will show the exact opposite.)

-- 
                                                          - Warp


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From: Stephen
Subject: Re: Quotable
Date: 2 Jun 2008 13:57:09
Message: <a3d84416qgsj31tpo7sngm2rlvdhqn5rte@4ax.com>
On Mon, 02 Jun 2008 09:29:24 -0700, Darren New <dne### [at] sanrrcom>
wrote:

>Stephen wrote:
>> Indeed, a straight edge and compass. What more do you need?
>
>A ruler?

No, I don't think so. ;)
-- 

Regards
     Stephen


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From: andrel
Subject: Re: Quotable
Date: 2 Jun 2008 15:00:18
Message: <48444370.5090202@hotmail.com>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>>   So when the electron hits the sensitive film *after* it has passed the
>>> slits, it goes back to the past and changes it so that it goes through
>>> only one of the slits after all?
> 
>> No. It either interferes with itself or not. You're assuming the only 
>> way it can interfere with itself is to go through both slits. There's no 
>> evidence that's the case, and much evidence that it isn't.
> 
>   So why does it interfere with itself when there are two slits but not
> when there is only one? If it was just one regular physical macroscopical
> particle it wouldn't matter how many slits there are: If it goes through
> one of them, it just goes through one of them, that's it. It doesn't even
> "know" that there are other slits.
>   However, when there are two slits, the electron passes through and starts
> interfering with itself, as if it has passed through both and changed
> direction in different ways.
> 
>   How else can this be explained? How does the electron "know" that there's
> another slit so that it "knows" to start interfering with itself, other than
> actually going through the other slit as well?
'It' knows that the second slit is there because an electron has an 
infinite size. Part of the problem is that you use 'it', implying that 
it is an identifiable object and it has a subconscious connotation of 
something finite.
> 
>   (I believe this has something to do with wave-particle duality: In the
> double-slit experiment the wave nature of the electron shows up: The wave
> goes through both slits and starts interfering with itself.)
Both 'wave' and 'particle' are concepts from classical physics that 
don't apply here.
In the double slit experiment you have a source of electrons, a double 
slit and a screen. You know that you had an electron at the source and 
you can compute the likelihood of the position on the screen that will 
light up, enabling you to estimate the pattern if you use a large number 
of electrons. Between the source and the screen, the electron passes 
through ever point in the universe and you are not even sure that the 
same electron hit the screen as the one you started with. Simply because 
'same' is not defined here.
A basic rule of quantum mechanics: don't try to visualize what happens. 
You can either visualize it or compute it, not both at the same time. ;)


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From: andrel
Subject: Re: Quotable
Date: 2 Jun 2008 15:17:06
Message: <48444760.50105@hotmail.com>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>>>   What the mathematical model *can* do is to give a distribution function
>>> which tells how the electron is distributed in space (a bit like a
>>> function which tells how the water is distributed, except that with
>>> the electron the "density" of the "water" is not constant).
> 
>> No, actually, it tells you the likelihood of finding it at any 
>> particular place, were you to look.
> 
>   Assuming the particle *is* at some specific location at any given time
> instead of being distributed in space.
> 
>> Yes, it can actually hit the other side of the Earth. It can also hit a 
>> week before you shoot it. Very unlikely, but possible.
> 
>   I don't believe in the time travelling. 
Luckily you don't have to believe it in order for it to exist. BTW I 
don't think what Darren proposes can actually happen, though it might be 
possible to create a situation that is indistinguishable from it.
> As for the location, I assume
> the probability of it hitting the other side of the Earth is so small that
> some physical constant prevents it.

The only thing that prevents it is the number of electrons you have to 
try it. Still even if it will never actually happen, yet the fact that 
it could will influence the outcome anyway.


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 15:17:08
Message: <48444734$1@news.povray.org>
Darren New wrote:
> Mueen Nawaz wrote:
>>     Yes - wasn't that proven only recently?
> 
> I heard about it recently, like in the last couple of years.

	Actually, I found it - proven in 1990.

> Something like 10^50 cuts or something?  I know it's on Wolfram's 
> mathworld somewhere, but I don't remember the name of it, so it's hard 
> to find.

http://en.wikipedia.org/wiki/Tarski%27s_circle-squaring_problem


-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 15:18:00
Message: <48444768$1@news.povray.org>
Warp wrote:
>> Indeed, a straight edge and compass. What more do you need?
> 
>   I assume that dividing the circle into an uncountable set of points.

	I posted the link in another message. The set of regions it is cut into 
is countably finite.

-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 15:37:13
Message: <48444be9$1@news.povray.org>
Warp wrote:
>   However, when there are two slits, the electron passes through and starts
> interfering with itself, as if it has passed through both and changed
> direction in different ways.
> 
>   How else can this be explained? How does the electron "know" that there's
> another slit so that it "knows" to start interfering with itself, other than
> actually going through the other slit as well?

	Your questions are interesting, but the conclusions do not necessarily 
follow. If you actually attempt to detect the electron passing through a 
slit, you'll detect it passing through only one slit (and you won't get 
an interference pattern). When you don't try to detect it, you get an 
interference pattern.

	You're concluding it passed through two slits when you don't try to 
detect it? It knows before passing through the slit that you're trying 
to detect it? Such a suggestion is about as weird as an electron 
interfering with itself. It may be true, or it may not be. I don't 
presume to know.

	As you yourself stated elsewhere, you get an interference pattern even 
when only one electron is shot at a time. However, the electron strikes 
the screen in only one place at a time. Looking at where they struck 
individually gives no evidence of any interference - it doesn't "weakly" 
strike two places at once. Looking at the whole set of locations the 
electron struck, though, does. One could simply explain this by saying 
that the presence of two slits causes the electron to act in a 
probabilistic manner - resulting in an interference pattern.

	And, AFAIK, that's the best explanation there is. I have a formalism 
that describes experimental results, and I don't have to resort to 
thinking about electrons interfering with themselves.

	The reason I don't want to declare self-interference is that there is 
no way I can test it (or as Darren would say - any attempt to show this 
fails). I can have two slits and put detectors at each slit. When you 
detect an electron passing through a slit, interference ceases. Why? If 
the electron can pass through both slits, why can't you actually detect 
this?

>>>   If there's "no evidence", what do you call the interference pattern?
>>> "Non-evidence"?
> 
>> Interference.
> 
>   The interference can be explained with the electron passing through both
> slits at the same time. Ergo the interference is evidence of that happening.
> (Note that "evidence" is not the same thing as "proof".)

	And detecting which slit an electron passes through is also evidence 
that it isn't passing through both slits.

-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 15:39:44
Message: <48444c80$1@news.povray.org>
Warp wrote:
>>         There is a non-zero probability that this can happen.
> 
>   I bet the probability is so small that it hits the barrier of some
> physical constant (Planck maybe?)

	I'm not sure what that means. Probability is a mathematical construct - 
not beholden to physical constants. If the probability is 1e-100, you 
can't use physics to conclude that it *won't* happen tomorrow.

-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 15:43:54
Message: <48444d7a$1@news.povray.org>
Darren New wrote:
> John VanSickle wrote:
>> I wouldn't say that it is truly random, but merely that predicting the 
>> outcome of any interaction requires information that is presently not 
>> available.
> 
> You would be incorrect. Google on "Bell's Inequality".
> 
>> For instance, the decay of unstable particles appears to happen 
>> randomly, but at what appears to be a predictable rate for aggregate 
>> amounts of like particles.  What is likely is that the particles decay 
>> when they encounter certain conditions (such as a gradient in the 
>> electric or magnetic potential) that is high enough to overcome the 
>> weak internal cohesiveness of the particle, causing it to come apart. 
> 
> That's the "hidden variable" theory. It has been disproven, multiple 
> times and with hundreds of different experiments. Boggling, isn't it?

	I question the assertion that it's been disproven. I think only a 
certain class of hidden variables have been shown not to exist. (Local 
vs non-local?)

-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:09:08
Message: <48445364$1@news.povray.org>
Mueen Nawaz wrote:
> http://en.wikipedia.org/wiki/Tarski%27s_circle-squaring_problem

Interestingly, following the links from there to 
http://en.wikipedia.org/wiki/Non-measurable_subset give an example of 
what might be a reality inconsistent with math:

"""
These sets are rich enough to include every conceivable definition of a 
set that arises in standard mathematics, but they require a lot of 
formalism to prove that sets are measurable.
"""

So if reality actually includes non-measurable sets (something that 
wouldn't seem too impossible, given the definition, such as "space where 
you can't pick any random position", i.e., quantum space), you already 
have a serious problem.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:09:32
Message: <4844537c@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> No, it only interferes with other electrons. The electrons it interferes 
>> with are electrons from other times. There's always a possibility that 
>> it lands at any particular place. Why is it any stranger that it 
>> interferes with electrons in the future than it is it interferes with 
>> itself?
> 
>   Because time travel doesn't exist?

At the quantum level, it most certainly does.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:21:16
Message: <4844563c$1@news.povray.org>
Warp wrote:
>   So why does it interfere with itself when there are two slits but not
> when there is only one?

I don't know, offhand.  That's actually one of the burning questions of 
quantum physics.  Are you saying you've figured it out? :-)

Incidentally, it doesn't interfere with itself - I misspoke. It 
interferes with other electrons. Sure, they only go through one at a 
time. What was that about time travel?

>   However, when there are two slits, the electron passes through and starts
> interfering with itself, as if it has passed through both and changed
> direction in different ways.

How do you know?  Every time you measure whether it went through both 
slits, the answer is "no, there was only one electron." You keep 
asserting this, with no evidence other than "I can't think of any other 
explanation", along with rejecting both evidence and other explanations.

>   How else can this be explained? How does the electron "know" that there's
> another slit so that it "knows" to start interfering with itself, other than
> actually going through the other slit as well?

Your intuition is confusing you. How does it "know" there's a back 
surface to the glass and therefore needs to reflect differently? How 
does it "know" there's another electron already "on the way" to where 
it's going and hence that position needs to be avoided?

Why is it a wave going through both slits but a particle by the time it 
gets to the detector?

>   (I believe this has something to do with wave-particle duality: In the
> double-slit experiment the wave nature of the electron shows up: The wave
> goes through both slits and starts interfering with itself.)

That's the older explanation from when physicists thought like you're 
thinking, yes. The math works like a wave function, so people thought it 
was a wave. It's not.

>>>   So you are saying that, even though the only possible explanation for
>>> interference patterns is that the electron passed through both slits,
>>> there's still no evidence of that?
> 
>> Yes. What makes you think that the only *possible* explanation is that 
>> the electron passed through both slits?
> 
>   What is the other explanation?

I don't know, and as far as I understand, nobody else does either. But 
all of the evidence so far suggests your interpretation is incorrect.

For example, if you do the same thing with photons, wait for them to go 
thru the slits, and after they've already passed through, you either 
turn on or off the detector that says which slit they went through, you 
always see them only go through one slit when the detector is on, and 
always generate interference probabilities when the detector is off. How 
do you explain that?

>   The interference can be explained with the electron passing through both
> slits at the same time.

Yes. But that's also at odds with many other experiments. If the 
electron goes through both slits, why is it that you never see it go 
through both slits when you put a detector behind each slit? It's one 
possible explanation with reams of experimental evidence against it.

The sun rising can be explained by angels pushing it along, as well, but 
that too is at odds with many other experiments. "I can't think of a 
better explanation" isn't the same as "the one I thought of must be 
true", *particularly* when evidence from other measurements is 
consistently at odds with one's explanation. (True regardless who "I" is 
in there.)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:23:26
Message: <484456be@news.povray.org>
Warp wrote:
>   I bet the probability is so small that it hits the barrier of some
> physical constant (Planck maybe?)

Possibly. Renormalization works, but I don't think anyone yet knows why.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:27:30
Message: <484457b2$1@news.povray.org>
Warp wrote:
>   Assuming the particle *is* at some specific location at any given time
> instead of being distributed in space.

That too. Note that's why I specified "when you look". It's easy to tell 
whether an electron is in a particular place at a particular time when 
you look. It's called, for example "Dynamic RAM."  It's more difficult 
to tell when you're not looking.

>> Yes, it can actually hit the other side of the Earth. It can also hit a 
>> week before you shoot it. Very unlikely, but possible.
> 
>   I don't believe in the time travelling. 

You're mistaken. Happens all the time (on a sufficiently small scale). 
QED doesn't work if you don't take it into account. Plus, most (or all) 
of QED is time-reversable. I.e., an electron going forward in time looks 
just like a positron going backwards in time.

Indeed, given a photon travels at the speed of light, time must be 
stopped. Yet, we know events happen during the lifetime of a photon. If 
time is stopped (by Lorenz contraction), why would a photon ever 
spontaneously change into something else?

> As for the location, I assume
> the probability of it hitting the other side of the Earth is so small that
> some physical constant prevents it.

Good to know. Your opinion has been noted and filed appropriately. ;-)

Seriously, there are (reputable) people who believe electrons are 
fungible because it's all the same electron moving around in time and space.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:33:57
Message: <48445935$1@news.povray.org>
Warp wrote:
>   Actually "quantum physics" means that everything is quantified.

Nobody has figured out for sure if space or time are quantified. Lots of 
speculation, but nothing concrete, last I heard.

> there's a minimum amount of everything (for example electric charge and
> mass), 

Nope. Electric charge, yes, but not mass. Photons will have mass 
proportional to their frequency, and frequency isn't apparently quantified.

> and everything is an integer multiple of that amount. You just can't
> have eg. half of the electric charge of an electron, for example.

Uh, yeah, you can, but that's because they found smaller things like 
quarks. I'll grant that nobody has found something with half the charge 
of a quark. :-)

>   Waves are also quantified for the same reason: There's a minimum amount
> of amplitude, for example, and all amplitudes are integer multiples of
> that amount.

Well, if you're talking about frequency, as far as I understand, this 
isn't true. There's no lower limit to the frequency of a photon, nor any 
quantum levels thereof. Indeed, if you believe in General Relativity, 
that'll tell you there's no quantum of frequency - look at a photon 
climbing out of a gravity well.

Photons are quantified, but not frequencies. There's a minimum amount of 
energy a collection of photons of a specific frequency can have, and 
it's an integer multiple of the energy of one photon, but there's no 
quantification between photons of different frequencies.

>   These "quants" behave oddly. Sometimes they behave like particles,
> sometimes they behave like waves, and sometimes they behave like both
> at the same time. Different measurements of the exact same quant can
> show wildly different behavior in this respect. (One experiment will
> clearly show that light behaves like a wave and not like a stream of
> particles, while another experiment will show the exact opposite.)

You are out of date by several decades, I believe. That's how the math 
works out, because the probabilities are two-dimensional. But you never 
wind up measuring waves as such. Just probabilities of certain events 
happening.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:35:10
Message: <4844597e$1@news.povray.org>
Mueen Nawaz wrote:
>     I question the assertion that it's been disproven. I think only a 
> certain class of hidden variables have been shown not to exist. (Local 
> vs non-local?)

I believe you're correct. I overgeneralized.

There are no hidden variables whose state is transported slower than the 
speed of light. Certainly if general relativity is wrong, there might be 
hidden quantum variables.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 16:40:42
Message: <48445aca$1@news.povray.org>
Warp wrote:
>   So why does it interfere with itself when there are two slits but not
> when there is only one? 

Here's another conceivable answer, btw:

The electron you shoot out second? It's the same electron you shot out 
the first time. Since it knows whether the slit was open or not last 
time, it knows whether to follow the probability distribution of a 
1-slit or 2-slit experiment. Since either is random, the fact there's a 
one-electron delay between the two cases isn't visible.

Now, why is that sillier than "it knows whether you're going to measure 
which slit it went through after it has already gone through them"? :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 17:39:59
Message: <484468af$1@news.povray.org>
Darren New wrote:
> Nope. Electric charge, yes, but not mass. Photons will have mass 
> proportional to their frequency, and frequency isn't apparently quantified.

	Define mass.

-- 
The next war will determine not what is right, but what is left.


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 17:53:47
Message: <48446beb@news.povray.org>
Mueen Nawaz wrote:
> Darren New wrote:
>> Nope. Electric charge, yes, but not mass. Photons will have mass 
>> proportional to their frequency, and frequency isn't apparently 
>> quantified.
> 
>     Define mass.

E=mc^2?  Isn't mass measured in electron-volts?

Why? What's your point?  (This isn't sarcastic. I don't know enough to 
know why someone who knows more would point out that I didn't define 
mass, or that my naive understanding of it isn't correct.)

Maybe mass is quantified at the quantum level, since mass seems to be 
related to gravity (as in, inertial mass seems to always equal 
gravitational mass) and gravity hasn't found a quantum theory yet, sure.

But frequency isn't "and everything is an integer multiple of that 
amount" kind of thing, as far as I know, right?

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 17:57:20
Message: <48446cc0$1@news.povray.org>
Warp wrote:
 >   These "quants" behave oddly. Sometimes they behave like particles,
 > sometimes they behave like waves, and sometimes they behave like both
 > at the same time.

Actually, you might be confused because you're not being precise enough.

The way I think you want to think about it is this:

"Sometimes they behave like particles" means "in some experiments, we 
get results whose mathematical formulation is isomorphic to the 
whatever-they-ares being particles."

"Sometimes they behave like waves" means "in other experiments, we get 
results whose mathematical formulation is isomorphic to the the behavior 
of waves."

In particular, the times you see "behavior like waves" is when you stop 
*measuring* "does it behave like a particle?"  The times you see 
"behavior like a particle" is when you stop *measuring* whether it 
behaves like waves. But in each case, you're explicitly excluding some 
of the behavior and not too unsurprisingly seeing the other behavior.

In other words, when you do the math, sometimes the results you get for 
electrons are the same results as those you get for waves. That doesn't 
mean electrons *are* waves, any more than it means that light behaving 
like a wave needs a medium to "wave" in order to travel.

Sort of like a PRNG. Some experiments you do, it looks random. That 
doesn't mean it's random. It just means you haven't seen the real thing, 
and you haven't measured whether it's deterministic or not. But every 
time you *do* measure whether it's deterministic, it looks like it is.
Every time you take a (good) PRNG and measure its statistical 
properties, it looks random. Every time you start a (good) PRNG from the 
same seed, you get the same values. That doesn't mean sometimes the PRNG 
is deterministic and sometimes it isn't.

Sort of like General Relativity. You can predict which way a satellite 
in outer space will go by assuming gravity is a force like muscular 
exertion is a force. That doesn't mean gravity *is* a force - it just 
has the same equations (modulo Lorenz contraction, of course).

 > Different measurements of the exact same quant can
 > show wildly different behavior in this respect.

"Exact same"? I didn't know you could tell electrons apart.

 > (One experiment will
 > clearly show that light behaves like a wave and not like a stream of
 > particles, while another experiment will show the exact opposite.)

Yes. That doesn't mean sometimes it *is* a wave and sometimes it *is* a 
particle. It means that sometimes the particle behaves in a way that can 
be predicted with the same mathematical formulas that predict the 
behavior of waves.

Plus, as I understand it, light as such doesn't have a specific 
"frequency". The light source does, but not the photons themselves. But 
I'll admit I'm probably very confused on this one. I.e., a photon isn't 
"waving" as such while it travels, but you can tell frequency by looking 
at the probability vectors of photons over time coming out of a source. 
If there's anyone who can actually explain that better to a layman, I'd 
love to hear it. :-)

Note that a single electron does *not* interfere with itself in the same 
way a wave does. If it did, it would cancel itself out sometimes, and 
that doesn't happen. You can set up a detector behind the two slits 
that's too imprecise to tell you *which* slit the electron went through, 
but can tell you it went through, and the two sets of detectors will 
count approximately the same number of events. Hence, electrons don't 
interfere with themselves in a wave-like manner. They just change the 
probabilities of where they'll land, and the formula for that is the 
same as the formula for a wave, and for the same reason - they're both 
multiplications (and hence convolutions) of cyclic 2-dimensional values.




(Oh, and as for "half the charge of an electron", the one that boggles 
my mind is spin-2 particles. A particle that's not symmetric when you 
turn it 360 degrees, but is when you turn it 720?)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: andrel
Subject: Re: Quotable
Date: 2 Jun 2008 18:24:14
Message: <4844733C.8080700@hotmail.com>
Darren New wrote:
> Mueen Nawaz wrote:
>> Darren New wrote:
>>> Nope. Electric charge, yes,
Though quarks are supposed to have fractional charge.
>>> but not mass. Photons will have mass 
>>> proportional to their frequency, and frequency isn't apparently 
>>> quantified.
>>
>>     Define mass.
> 
> E=mc^2?  Isn't mass measured in electron-volts?
> 
> Why? What's your point?  (This isn't sarcastic. I don't know enough to 
> know why someone who knows more would point out that I didn't define 
> mass, or that my naive understanding of it isn't correct.)
> 

Also not sure what Mueen means, but the m in E=mc^2 is the m that was 
used by einstein. IIRC the current definition would require a division 
by sqrt(1-v^2/c^2). The old definition was certainly not quantified for 
arbitrary velocities.

> Maybe mass is quantified at the quantum level, since mass seems to be 
> related to gravity (as in, inertial mass seems to always equal 
> gravitational mass) and gravity hasn't found a quantum theory yet, sure.

I have still not heard if the experiment to do gravitational experiments 
with anti-hydrogen (anti-proton with positron) did succeed, but I left 
the field some time ago.

> But frequency isn't "and everything is an integer multiple of that 
> amount" kind of thing, as far as I know, right?
>


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:16:52
Message: <48447f64@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> >   Because time travel doesn't exist?

> At the quantum level, it most certainly does.

  That would create paradoxes.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:26:25
Message: <484481a1@news.povray.org>
Mueen Nawaz <m.n### [at] ieeeorg> wrote:
> One could simply explain this by saying 
> that the presence of two slits causes the electron to act in a 
> probabilistic manner - resulting in an interference pattern.

  That's not an explanation. You are not telling what exactly is it
with the two slits that causes the interference pattern, you are just
telling that when there are two slits, there is an interference pattern.
Thus you are not explaining anything, you are simply stating the result
of the experiment.

>         And, AFAIK, that's the best explanation there is.

  Except that it's not an explanation at all. It's simply stating the
result of the experiment.

>         And detecting which slit an electron passes through is also evidence 
> that it isn't passing through both slits.

  It's only evidence that measurements mess up with the electron. It
doesn't explain the reason for the interference pattern.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:44:21
Message: <484485d5@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> Incidentally, it doesn't interfere with itself - I misspoke. It 
> interferes with other electrons.

  What other electrons?

> Sure, they only go through one at a 
> time. What was that about time travel?

  The electron somehow magically knows that in the future more electrons
will be there and act accordingly?

> >   However, when there are two slits, the electron passes through and starts
> > interfering with itself, as if it has passed through both and changed
> > direction in different ways.

> How do you know?

  I don't, but there seems to be just two alternatives:

1) The electron passes through both slits at the same time, interferes
   with itself, and thus acts according to a logical mathematical formula.

2) Something completely unknown is happening which we can't even begin
   to theoretize.

  From these two you want me to choose number 2. Moreover, you seem to
be saying that an electron passing through two slits at the same time is
too hard to believe, but things like time travel are completely believable
and understandable. Your reasoning doesn't make too much sense to me.

>  Every time you measure whether it went through both 
> slits, the answer is "no, there was only one electron."

  Of course there was only one electron. And yes, measuring messes up
the electron. So what?

> You keep 
> asserting this, with no evidence other than "I can't think of any other 
> explanation", along with rejecting both evidence and other explanations.

  You want me to believe some stories about time-travelling electrons
instead of thinking that the interference is simply caused by the
electron going through both slits as if it was a wave. Honestly, what
do you expect me to believe more, as a rational person?

> Your intuition is confusing you. How does it "know" there's a back 
> surface to the glass and therefore needs to reflect differently? How 
> does it "know" there's another electron already "on the way" to where 
> it's going and hence that position needs to be avoided?

  What another electron? I don't understand.

> Why is it a wave going through both slits but a particle by the time it 
> gets to the detector?

  Why do quanta behave both like waves and particles? I don't know.
It just seems they do.

> >> Yes. What makes you think that the only *possible* explanation is that 
> >> the electron passed through both slits?
> > 
> >   What is the other explanation?

> I don't know, and as far as I understand, nobody else does either. But 
> all of the evidence so far suggests your interpretation is incorrect.

  *All* the evidence? Including the interference pattern?

  How come a phenomenon which was evidence for the electron passing as
a wave through both slits has suddenly become evidence of the contrary?

> For example, if you do the same thing with photons, wait for them to go 
> thru the slits, and after they've already passed through, you either 
> turn on or off the detector that says which slit they went through, you 
> always see them only go through one slit when the detector is on, and 
> always generate interference probabilities when the detector is off. How 
> do you explain that?

  I don't know why measuring quanta messes up with their behavior.

> >   The interference can be explained with the electron passing through both
> > slits at the same time.

> Yes.

  First you say that *all* evidence suggests that the claim is incorrect,
and now you admit that at least one piece of evidence doesn't.

> But that's also at odds with many other experiments. If the 
> electron goes through both slits, why is it that you never see it go 
> through both slits when you put a detector behind each slit?

  I don't know why measuring quanta messes up with their behavior.

> The sun rising can be explained by angels pushing it along, as well,

  Or electrons travelling in time.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:47:38
Message: <4844869a@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> The electron you shoot out second? It's the same electron you shot out 
> the first time.

  And you insinuate *my* explanation makes no sense.

> Since it knows whether the slit was open or not last 
> time, it knows whether to follow the probability distribution of a 
> 1-slit or 2-slit experiment.

  Yeah, electrons are sentient beings now, and have memory.

> Now, why is that sillier than "it knows whether you're going to measure 
> which slit it went through after it has already gone through them"? :-)

  Explain to me how would you measure the location of an electron without
affecting it in any way.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:48:40
Message: <484486d7@news.povray.org>
Mueen Nawaz <m.n### [at] ieeeorg> wrote:
> Warp wrote:
> >>         There is a non-zero probability that this can happen.
> > 
> >   I bet the probability is so small that it hits the barrier of some
> > physical constant (Planck maybe?)

>         I'm not sure what that means. Probability is a mathematical construct - 
> not beholden to physical constants.

  Electrons are physical particles, not mathematical constructs.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 19:55:40
Message: <4844887b@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> Seriously, there are (reputable) people who believe electrons are 
> fungible because it's all the same electron moving around in time and space.

  Which does *not* go through the two slits at the same time. Everything
else is ok. The same electron being here and at the other side of the
Andromeda galaxy? No problem. Electrons travelling in time and acting
depending on what happens one week from now? No problem. The one and the
same electron being shot, detected in a photographic film, and then shot
again a minute later? No problem.
  But an electron passing through two slits at the same time? Absolute
nonsense. Laughable even as a wild theory.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 20:02:56
Message: <48448a30@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> > and everything is an integer multiple of that amount. You just can't
> > have eg. half of the electric charge of an electron, for example.

> Uh, yeah, you can, but that's because they found smaller things like 
> quarks.

  Except that the electron is an elementary particle, with no known
subdivision into smaller components. And, as far as I know, the charge
of an electron is the smallest known charge.

> >   These "quants" behave oddly. Sometimes they behave like particles,
> > sometimes they behave like waves, and sometimes they behave like both
> > at the same time. Different measurements of the exact same quant can
> > show wildly different behavior in this respect. (One experiment will
> > clearly show that light behaves like a wave and not like a stream of
> > particles, while another experiment will show the exact opposite.)

> You are out of date by several decades, I believe.

  You are saying that all experiments which show light as behaving like
a wave and the experiments showing it behaving like a stream of particles
are wrong?

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 20:07:51
Message: <48448b56@news.povray.org>
andrel <a_l### [at] hotmailcom> wrote:
> Also not sure what Mueen means, but the m in E=mc^2 is the m that was 
> used by einstein. IIRC the current definition would require a division 
> by sqrt(1-v^2/c^2). The old definition was certainly not quantified for 
> arbitrary velocities.

  I really can't understand what you are talking about. The 'm' which
Einstein used (and others before him) is what is currently used. There's
no "current definition of m".

  Don't confuse the 'm' in the E=mc^2 with 'm0' (m subscript zero), which
is the rest mass of an object. The 'm' in E=mc^2 is the relativistic mass,
and equal to m0/sqrt(1-v^2/c^2). That was the definition back then, and
that's the definition today. It hasn't changed.

-- 
                                                          - Warp


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From: Warp
Subject: Re: Quotable
Date: 2 Jun 2008 20:15:15
Message: <48448d13@news.povray.org>
Darren New <dne### [at] sanrrcom> wrote:
> Sort of like General Relativity. You can predict which way a satellite 
> in outer space will go by assuming gravity is a force like muscular 
> exertion is a force. That doesn't mean gravity *is* a force - it just 
> has the same equations (modulo Lorenz contraction, of course).

  Are you sure Lorentz contraction is enough to "fix" the regular
newtonian gravitation calculations using forces? Gravity wells mess
up with time as well.

> Note that a single electron does *not* interfere with itself in the same 
> way a wave does. If it did, it would cancel itself out sometimes, and 
> that doesn't happen.

  Two waves with the same frequency interfering each other don't
necessarily cancel each other at any moment.

  Besides, what would "cancelling itself" mean with an electron?
Wouldn't it mean that it just goes straight, because the forces cancel
each other, and thus don't affect the direction of the electron?
Certainly some electrons in the slit experiment go straight?

-- 
                                                          - Warp


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:19:12
Message: <48448e00$1@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>>>   Because time travel doesn't exist?
>> At the quantum level, it most certainly does.
>   That would create paradoxes.

And the reason you say this is....?

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:37:43
Message: <48449257$1@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> The electron you shoot out second? It's the same electron you shot out 
>> the first time.
> 
>   And you insinuate *my* explanation makes no sense.

No. I'm just pointing out that your explanation isn't the only 
*possible* one. You are discounting other explanations that, to *you*, 
seem less likely, rather than doing any sort of experiment (or looking 
up any of the experiments that countless others have done).

>> Since it knows whether the slit was open or not last 
>> time, it knows whether to follow the probability distribution of a 
>> 1-slit or 2-slit experiment.
> 
>   Yeah, electrons are sentient beings now, and have memory.

Hey, you're the one that makes them switch between waves and particles 
after the fact.

>> Now, why is that sillier than "it knows whether you're going to measure 
>> which slit it went through after it has already gone through them"? :-)
> 
>   Explain to me how would you measure the location of an electron without
> affecting it in any way.

By measuring it later in time than the property you're trying to detect.

How do you measure which slit (or both) the electron went through 
without affecting it? You do so by putting detectors *after* the slit. 
Do you think the electron can go thru both slits and then only affect 
one detector, but only if there's two detectors instead of one?

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:38:46
Message: <48449296$1@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Incidentally, it doesn't interfere with itself - I misspoke. It 
>> interferes with other electrons.
> 
>   What other electrons?

The other electrons in the experiment. You don't get an interference 
pattern from a single electron - that's exactly why people say electrons 
are particles. You get an interference pattern when you average the 
probability of many electrons.

>> Sure, they only go through one at a 
>> time. What was that about time travel?
> 
>   The electron somehow magically knows that in the future more electrons
> will be there and act accordingly?

I don't know. Nobody knows. Except, apparently, you. :-)

> 1) The electron passes through both slits at the same time, interferes
>    with itself, and thus acts according to a logical mathematical formula.

And yet, somehow, whenever you look, it only goes through one slit at a 
time. How does it know?

> 2) Something completely unknown is happening which we can't even begin
>    to theoretize.

Yes, that. Actually, lots of theories. Little progress.

That's what all the "brane" theory and string theory and all that is about.

>   From these two you want me to choose number 2. 

Given the choice between a theory that has copious experimental evidence 
against it, and saying "we don't have a good theory", yes, picking "we 
don't have a good theory" is better.

 > Moreover, you seem to
> be saying that an electron passing through two slits at the same time is
> too hard to believe,

It's not too hard to believe. It's just counter to every experimental 
measurement.

> but things like time travel are completely believable
> and understandable.

Checked to 15 decimal places or so.

> Your reasoning doesn't make too much sense to me.

Common sense doesn't really apply to quantum electrodynamics.

> 
>>  Every time you measure whether it went through both 
>> slits, the answer is "no, there was only one electron."
> 
>   Of course there was only one electron. And yes, measuring messes up
> the electron. So what?

If every time you measure whether it went through both slits, the answer 
is "no", why do you think it ever goes through both slits? Even if you 
measure after it has already passed through the slits?

>> You keep 
>> asserting this, with no evidence other than "I can't think of any other 
>> explanation", along with rejecting both evidence and other explanations.
> 
>   You want me to believe some stories about time-travelling electrons
> instead of thinking that the interference is simply caused by the
> electron going through both slits as if it was a wave. Honestly, what
> do you expect me to believe more, as a rational person?

"You expect me to believe you could just pick up a lump of plastic, rub 
your fingers on it, and magically communicate with someone on the other 
side of the world? What kind of fool do you think I am?"

Quantum physics isn't intuitive. But you don't get to throw out 
experimental evidence just because you can't figure out *why* you get 
those results.

How do you explain electrons going through both slits if, after it goes 
through the slits, you measure which slit it went through, and you 
always get the answer "only one"?

> 
>> Your intuition is confusing you. How does it "know" there's a back 
>> surface to the glass and therefore needs to reflect differently? How 
>> does it "know" there's another electron already "on the way" to where 
>> it's going and hence that position needs to be avoided?
> 
>   What another electron? I don't understand.

Electrons don't interfere with or cancel themselves out. It's a 
probability thing. One flip of a coin doesn't give you a result of "one 
half head and one half tail."

>> Why is it a wave going through both slits but a particle by the time it 
>> gets to the detector?
> 
>   Why do quanta behave both like waves and particles? I don't know.
> It just seems they do.

Then why is it so hard to believe that's true even without it going thru 
both slits?

>>>> Yes. What makes you think that the only *possible* explanation is that 
>>>> the electron passed through both slits?
>>>   What is the other explanation?
> 
>> I don't know, and as far as I understand, nobody else does either. But 
>> all of the evidence so far suggests your interpretation is incorrect.
> 
>   *All* the evidence? Including the interference pattern?

How do you know it went thru both slits? Every time you ask, it only 
goes through one slit. You're saying "the only way you can have an 
interference pattern is for every electron to go through both slits." 
That's an invalid inference.

>   How come a phenomenon which was evidence for the electron passing as
> a wave through both slits has suddenly become evidence of the contrary?

It hasn't. You are mistaken that the only possible explanation is that 
the electron is a wave as it passes through both slits.

>> For example, if you do the same thing with photons, wait for them to go 
>> thru the slits, and after they've already passed through, you either 
>> turn on or off the detector that says which slit they went through, you 
>> always see them only go through one slit when the detector is on, and 
>> always generate interference probabilities when the detector is off. How 
>> do you explain that?
> 
>   I don't know why measuring quanta messes up with their behavior.

So do you believe in time travel or not? Because clearly the decision as 
to whether the electron went thru one slit or both is traveling back in 
time in this experiment, *if* that's what's happening.

>>>   The interference can be explained with the electron passing through both
>>> slits at the same time.
> 
>> Yes.
> 
>   First you say that *all* evidence suggests that the claim is incorrect,
> and now you admit that at least one piece of evidence doesn't.

No. The interference can also be "explained" by God screwing with our 
heads, by intelligent electrons trying to confuse you, or by magic fairy 
dust. None of those are correct either.

How does one determine this? One does experiments that would have 
different results if electrons were intelligent, or if fairies were 
present, and which consistently find negative results. Welcome to science.

>> But that's also at odds with many other experiments. If the 
>> electron goes through both slits, why is it that you never see it go 
>> through both slits when you put a detector behind each slit?
> 
>   I don't know why measuring quanta messes up with their behavior.

But you *do* know that they go through both slits. Interesting.

>> The sun rising can be explained by angels pushing it along, as well,
>   Or electrons travelling in time.

Mmmmm.  The sweet, sweet smell of assertive ignorance.

How come it's reasonable that time isn't comparable everywhere, but that 
subatomic particles can't travel in time?

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:40:48
Message: <48449310$1@news.povray.org>
Warp wrote:
>   But an electron passing through two slits at the same time? Absolute
> nonsense. Laughable even as a wild theory.

No, it's not a wild theory. It's just a disproven theory. As in, lots of 
evidence against it. The "there's only one electron" is a wild theory.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:41:48
Message: <4844934c$1@news.povray.org>
andrel wrote:
> I have still not heard if the experiment to do gravitational experiments 
> with anti-hydrogen (anti-proton with positron) did succeed, but I left 
> the field some time ago.

I *did* hear where they managed experimental evidence that the speed of 
gravity is at most twice the speed of light, and likely the speed of 
light exactly.  Which I thought was cool.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


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From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 20:45:47
Message: <4844943b$1@news.povray.org>
Warp wrote:
>   That's not an explanation. You are not telling what exactly is it
> with the two slits that causes the interference pattern, you are just
> telling that when there are two slits, there is an interference pattern.
> Thus you are not explaining anything, you are simply stating the result
> of the experiment.

	Precisely. It's a descriptive formalism. AFAIK, physicists simply don't 
know what is going on, and nor are they sure there is any more to it 
than the above.

>>         And, AFAIK, that's the best explanation there is.
> 
>   Except that it's not an explanation at all. It's simply stating the
> result of the experiment.

	Isn't that what a theory is?

	A theory is not a theory if it is not testable. My "explanation" is 
testable. If you do the experiment tomorrow, my description will hold true.

	Your claim that it passes through both slits is untestable. We can 
never detect that it is doing this.

>>         And detecting which slit an electron passes through is also evidence 
>> that it isn't passing through both slits.
> 
>   It's only evidence that measurements mess up with the electron. It
> doesn't explain the reason for the interference pattern.

	And that there is an interference pattern does not explain how many 
slits the wave passed through.

-- 
A closed mouth gathers no feet...


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:47:47
Message: <484494b3$1@news.povray.org>
Warp wrote:
>   Except that the electron is an elementary particle, with no known
> subdivision into smaller components. And, as far as I know, the charge
> of an electron is the smallest known charge.

Yet, oddly enough, the proton seems to be composed of three quarks each 
with some charge, and has the same charge as an electron. You know, a 
really fast google on "quark charge" turns up

http://education.jlab.org/qa/quark_05.html

Now, given that electrons seem to be elementary particles, and quarks 
seem to have a partial charge compared to electrons, there's some mighty 
funky stuff going on with charge there.

>   You are saying that all experiments which show light as behaving like
> a wave and the experiments showing it behaving like a stream of particles
> are wrong?

No. I'm saying that your phrase "like a wave" is too imprecise to be 
worth talking about. Define "like".

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 20:50:01
Message: <48449539@news.povray.org>
Warp wrote:
>   Are you sure Lorentz contraction is enough to "fix" the regular
> newtonian gravitation calculations using forces? Gravity wells mess
> up with time as well.

It was an analogy. Don't push it too far.

>> Note that a single electron does *not* interfere with itself in the same 
>> way a wave does. If it did, it would cancel itself out sometimes, and 
>> that doesn't happen.
> 
>   Two waves with the same frequency interfering each other don't
> necessarily cancel each other at any moment.

No matter how you arrange it, the number of electrons matches up, even 
if there are places where no measurable number of electrons get found.

>   Besides, what would "cancelling itself" mean with an electron?

I don't know. You're the one saying the electron interferes with 
*itself*. In spite of the fact that it never seems to interfere with 
itself to zero.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 20:52:04
Message: <484495b4$1@news.povray.org>
Warp wrote:
>>>>         There is a non-zero probability that this can happen.
>>>   I bet the probability is so small that it hits the barrier of some
>>> physical constant (Planck maybe?)
> 
>>         I'm not sure what that means. Probability is a mathematical construct - 
>> not beholden to physical constants.
> 
>   Electrons are physical particles, not mathematical constructs.

	Yes, but probabilities of electrons doing something are mathematical 
constructs.

	If I calculate the probability of an event occurring to be much smaller 
than any physical constant, it can still happen tomorrow.

-- 
A closed mouth gathers no feet...


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


Post a reply to this message

From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 20:57:20
Message: <484496f0@news.povray.org>
Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>>> and everything is an integer multiple of that amount. You just can't
>>> have eg. half of the electric charge of an electron, for example.
> 
>> Uh, yeah, you can, but that's because they found smaller things like 
>> quarks.
> 
>   Except that the electron is an elementary particle, with no known
> subdivision into smaller components. And, as far as I know, the charge
> of an electron is the smallest known charge.

	Darren just told you otherwise. An electron is not an elementary 
particle, and quarks can have smaller charges.

-- 
A closed mouth gathers no feet...


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


Post a reply to this message

From: Darren New
Subject: Re: Quotable
Date: 2 Jun 2008 21:09:49
Message: <484499dd@news.povray.org>
Darren New wrote:
> You would be incorrect. Google on "Bell's Inequality".

Actually, here's a pretty easy to read description of one such 
experiment, that I just happened to wander across while reading 
something else:

http://www.overcomingbias.com/2008/05/bells-theorem-n.html

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."


Post a reply to this message

From: Mueen Nawaz
Subject: Re: Quotable
Date: 2 Jun 2008 21:11:27
Message: <48449a3f$1@news.povray.org>
Darren New wrote:
> Mueen Nawaz wrote:
>> Darren New wrote:
>>> Nope. Electric charge, yes, but not mass. Photons will have mass 
>>> proportional to their frequency, and frequency isn't apparently 
>>> quantified.
>>
>>     Define mass.
> 
> E=mc^2?  Isn't mass measured in electron-volts?
> 
> Why? What's your point?  (This isn't sarcastic. I don't know enough to 
> know why someone who knows more would point out that I didn't define 
> mass, or that my naive understanding of it isn't correct.)

	The usual convention I've seen is to state that photons have momentum, 
not mass. A lot of physics textbooks (these days) don't talk about 
relativistic mass or mass changing when one speeds up.

	The original formalism by Einstein did have the mass changing.

	I'm not saying your definition is inconsistent, but I think physicists 
did not like the suggestion that a body gains more mass just by going 
faster.

You can see a bit of it here:

http://en.wikipedia.org/wiki/Mass_in_special_relativity#Controversy

	I'm used to people meaning "rest mass" when they just say mass. And a 
photon has 0 rest mass.

	Doing a Google search, it seems people are divided as to what they call 
"mass". For example, the American Institute of Physics page here 
casually refers to the rest mass as simply mass:

http://www.aip.org/pnu/2003/split/625-2.html

	Nothing deep - just wanted to make sure we were talking about the same 
thing.

-- 
A closed mouth gathers no feet...


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl


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