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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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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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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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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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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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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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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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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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."

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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."

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