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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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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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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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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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."

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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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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."

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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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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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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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