Nicolas Alvarez <nic### [at] gmailisthebestcom> wrote:

> > nemesis wrote:
> >
> >> a more direct link in his own site:
> >> http://www.imagico.de/pov/metamaterials.html
> >
> > Woah - so you mean POV-Ray already does this *now*?
> >
> > Now suddenly the subject line seems even more appropriate. ;-)
>
> WOAH

updated the "External links" section in the wikipedia article to point to the
very handy visual presentation by Hormann...

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"Stephen" <mcavoys_AT_aolDOT.com> wrote in message 
news:web.473305e34b19b3ff726bd13c0@news.povray.org...
> Invisible <voi### [at] devnull> wrote:
>
>>
>> * Electricity does not, under any remotely "normal" conditions, produce
>> light or affect it in any way. (E.g., you can't bend light using
>> electricity.) The same goes for magnetism.
>>
> I thought lightning was normal at least in a storm.
>
>> (I still can't figure out why you can use an oscilator to make radio
>> waves, but not light rays...)
>
> If you oscillate something fast enough it will heat up and emit light.

     Oh wow! When I was about 20('83), I remember borrowing a friends 
German-made echo box for my (then horrible) lecky guitar, (it was a 
*fantastic* echo box, but I can't remember what it was called), and it had 
two lime green flourescent 'beams' that met in the middle when you hit the 
sweet notes. Is that what you mean?

    (Anyway, I'm looking for loops for my old Copycat now... That's damn 
good too...)   ;)

      Sorry, just reminiscing...    ;)


         ~Steve~




>
> Stephen
>
>

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> It's a phenomenon that has something to do with electricity, magnetism, 
> waves and particles, but nobody really understands what exactly. ;-)
>
> Specifically, light is an electromagnetic wave (or is it a subatomic 
> particle?) in a particular frequency range (or is that particle energy?) 
> that registers in our eyes due to the chemical transformations it induces 
> in certain protein groups.

E=MC^2
All matter is both mass and energy.
Photons are "packets" of energy that fluxuate between
electical potential and magnetic potential at a certain frequency,
a.k.a. an electromagnetic wave.
They have more energy than an electron.

> However, it's really damn unusual for a material's electrical or magnetic 
> properties to have any bearing at all on its optical properties.

This is a common misconception.
The color of normal objects IS an electrical property,
it is the variation in electrical conductivity at optical frequencies.

> * Impure water is an excellent conductor, while pure water is a very good 
> insulator. Yet both substances have almost identical optical properties.

Resistance in materials varies by frequency.
Both salt-water and pure water are conductive at optical frequencies.

> * Iron is highly magnetic, while aluminium isn't. Good luck telling the 
> two metals apart by their appearence!
>
> * Electricity does not, under any remotely "normal" conditions, produce 
> light or affect it in any way. (E.g., you can't bend light using 
> electricity.) The same goes for magnetism.

Because photons are in high frequency flux, they have both positive
and negative charge, or no DC charge (depending on
how you look at it).

> Sure, theoretically they're related. But it's not something you see in the 
> real world very often. ;-)
>
> (I still can't figure out why you can use an oscilator to make radio 
> waves, but not light rays...)

Imagine three arrow vectors sitting at the origin, they point X,Y,Z,
this represents mass, electical, and magnetic.
The arrows must maintain the same overall vector length
X+Y+Z = k. However, they can fluctuate.

If a photon collides with something it regains its mass, so the
electrical and magnetic portions are gone, if the photon then
reflects it again has no mass, but electical and magnetic.

In a solar panel the photon collides, gains mass, but then at
lower frequencies it's conduductive, so only a portion is
reflected as radiation, an electron sized chunk of the energy
goes off down the wires.

As an electron is excited to high frequencies by equipment,
many of the components (like wires) have high resistance to
high frequencies.  That is why lasers use rubies, or gas tubes,
they are controlable high frequency oscilators that are still
conductive at optical frequencies.

That is also why you can fit more information down a fiber-
optic line than a copper line, fiber can operate at higher frequencies.

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Alain wrote:
> A wave guide have ior <1 for radio waves. You can't find the equivalent 
> for IR and visible light.

Huh. Why not?  Just because of the size of the atoms you'd have to build 
it from or something?

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Invisible wrote:
> bizare that electronic properties should actually affect optical ones, 
> but there we are.)

Actually, the only interactions that take place outside the nucleus are 
between electrons (and antielectrons, I guess) and photons, so it seems 
pretty *necessary* more than *bizarre*. :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Invisible wrote:
> However, it's really damn unusual for a material's electrical or 
> magnetic properties to have any bearing at all on its optical properties.

That's why mirrors made out of wood work so well, after all. :-)

> * Iron is highly magnetic, while aluminium isn't. Good luck telling the 
> two metals apart by their appearence!

Magnetism is a field of photons at a frequency you just can't see.

> * Electricity does not, under any remotely "normal" conditions, produce 
> light or affect it in any way. (E.g., you can't bend light using 
> electricity.) The same goes for magnetism.

Except for photoelectric effects, LEDs, solar cells, florescent light 
bulbs, all that sort of thing.

> Sure, theoretically they're related. But it's not something you see in 
> the real world very often. ;-)

Don't you use a computer? What do you think you're looking at?

> (I still can't figure out why you can use an oscilator to make radio 
> waves, but not light rays...)

You can. It just has to osscilate a lot faster.

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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M_a_r_c wrote:
> Is not a laser an excitated resonant optical cavity eg a oscillator?

No. You have to pump up the electrons into higher valences, and then 
when one photon hits, it causes the excited atom to drop the next photon 
at the same frequency and phase, because that's how the math comes out 
for photons. (It's the opposite for electrons, which is why you can't 
have more than two electrons in the same place and phase and all.)

The resonance comes from putting a mirror at each end to get the photons 
crossing the substrate more than once, so they have a better chance of 
hitting more atoms. But in theory, it would work if you just made a 
sufficiently long tube, or you could keep the atoms pumped up without 
interfering with the emmision. (The latter is what laser LEDs do, I think.)

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Vincent Le Chevalier wrote:
> And what makes it work is that the mirrors build a resonant optical cavity, 

I'm pretty sure that's not fundamental to getting the photons in phase.

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Phil Cook wrote:
> On a more serious note can anyone explain refraction in terms of 
> particles.

Yes.

http://www.amazon.com/QED-Strange-Princeton-Science-Library/dp/0691125759/ref=pd_bbs_1



-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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And lo on Fri, 09 Nov 2007 00:41:46 -0000, Darren New <dne### [at] sanrrcom> 
 

did spake, saying:

> Phil Cook wrote:
>> On a more serious note can anyone explain refraction in terms of  

>> particles.
>
> Yes.
>
> http://www.amazon.com/QED-Strange-Princeton-Science-Library/dp/0691125
759/ref=pd_bbs_1
Thanks, though I note one commentator said "The problem is that we never
  

get an explanation for why the vectors point the way the do, are rotated
  

just so, etc. Without that it's simply voodoo, and nothing has been  

explained." never mind. Amazon UK stocks it, but I'll check out my local
  

store first.

-- 

Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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