Invisible wrote:
> Well, you know, there are conductive materials that are reflective, and 
> ones that aren't. There are insulators that are reflective, and ones 
> that aren't. There seems to be little correlation here.

I suppose if you don't understand what makes something a conductor or 
what makes it reflective, that could be the case, yes.

>>> * 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.
> 
> Solar cells work by using strange chemistry rather than directly turning 
> light into electricity. (Presumably that's why they're so inefficient.)

Depends on the solar cell, but in general, I think when you say "strange 
chemistry", you don't understand that "chemistry" is an electromagnetic 
effect.

> Florescent light bulbs work by stimulating atoms to release photons, not 
> by directly turning electric oscilations into light.

And what is it that stimulates atoms to release photons?

> I have no clue why LEDs work. But apparently they do. ;-)

You have a crystal of semiconductor (i.e., 4 valence electrons), one 
side of which is doped with a mild concentration of atoms with 5 valence 
electrons, one with a mild concentration of 3 valence. (Say, gallium and 
arsinide.) You put negative voltage (i.e., an excess of electrons) on 
the side with 5 electrons, and it pushes them across the gap to the side 
with waiting "holes", into which they fall. As they fall, they release a 
photon of a color specific to how far they fall.

Originally, the cheapest chemicals to do this with had holes deep enough 
to emit red light. Hence the traditional red LEDs.

For bonus: A light sensitive diode is the same thing, basically, with 
less electricity. When light hits it, it knocks an electron free, which 
can then migrate across the junction and into the + side of the voltage, 
causing current that can be detected.

So LEDs both turn electricity *directly* into photons and vice versa.

>> Don't you use a computer? What do you think you're looking at?
> 
> Electricity can be used to excite atoms in such a way that they release 
> photons. So can heat energy, chemical energy, and all kinds of other 
> energy.

Nope. Heat doesn't stimulate atoms to release photons. The electrons in 
atoms banging into electrons in other atoms generates photons. When you 
heat atoms up, they bang into each other much more.

But take a bunch of atoms that are very hot but going all the same way, 
and you won't get much light out, until they hit something.  You know, 
like a cosmic ray.

And, as I said, "chemical energy" is energy in the valence electrons of 
atoms. Hence, it's electromagnetic.

> So it seems that unless you can find a material with an index of 
> refraction of several thousand, you aren't going to make light with an 
> electric oscilator.

Well, no, not like that sort of thing. You'd have to use a quantum-scale 
ossilator.

-- 
   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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