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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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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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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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...


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                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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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."

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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."

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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...


                     /\  /\               /\  /
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                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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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...


                     /\  /\               /\  /
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                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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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."

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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...


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                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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