New 'iPhoD' can 'adjust the speed of light by turning a knob' Optical stuff is great, as everyone knows: optical links mean huge bandwidth right now, and computers running on photons rather than electrons might be truly amazing things - tremendously powerful, very economical of energy, and potentially able to exploit quantum effects to achieve all manner of mindbending feats. But …
Nah, patent. Even Apple wouldn't dare go up against the Mad Military in a court of lore[1]. They'll not hesitate to try to patent and/or claim other people's ideas, though.
"We invented the GUI! Windows copied us!"
So X/PARC and Digital Research were just sitting there playing with themselves, were they? Yeah right, Steve. NURSE!
[1] No, that wasn't a typo. Think about it.
... as you think.
Heisenberg tells us that you can't measure something without changing it, or more (less?) precisely, you can't know everything about something in full detail.
Therefore, if the Feds read your mail before you send it, then the copy you send won't be the copy they've read... :-)
In physics in school they drummed 2 things into you constantly:
1. Energy can't be created or destroyed
2. The speed of light is constant
If (2) isn't true any more I'm glad I got out of physics at high school! God knows how I'd answer the homework if C isn't a constant any more :p
It would appear they didn't drum constantly enough.
Your point 2 should be stated as "The speed of light *in a vacuum* is constant.
This is a very important distinction as light travels at different speeds depending on the transmission medium. Just look up refraction for and everyday example of the effects of this.
The speed of light's only constant in a vacuum; when travelling through a transparent medium it can be (and is) different.
That's not an obscure physics effect with no practical implications either; amongst other things it's the mechanism lens use to work, including the ones in eyes!
The speed of light is constant - in a particular medium with fixed properties (remember the c most talked about is the speed of light in a vacuum, which is faster than the speed of light through the atmosphere and so on. Go re-read your high school physics books on refraction!). These guys are simply talking about changing the properties of the rubidium vapour, thus altering the speed of light in that substance. However, all light in that substance at that particular attunement will move at the same speed. So there you go. All sorted out for you.
"2. The speed of light is constant"
The speed of 'light' depends on the properties of the medium that it's traveling in. For a bulk medium, like the vacuum of space, a block of glass, etc; this is easy enough to work out and the behaviour of the waves/photons, whatever, is easily predicted. Hence school level physics.
When the photons start interacting with exotic substances that absorb and re-emit, then it all gets very complicated and scientific articles are born.
The constant "c" (as in "just 'c' ") is the speed of light **in a vacuum**.
The speed of light can and does vary, depending on the material (or lack thereof) through which the light moves.
Thus: c_Rb != c_vacuum
It is even possible for physical charged particles (electrons and/or protons) to **exceed** the speed of light **of a given moderating material**, if the particles have enough momentum. For a more detailed explanation, look up Cherenkov radiation:
-- http://en.wikipedia.org/wiki/Cherenkov_radiation
Ah yes, we've all heard "The speed of light is constant and is approximately 3x10^8 ms^-1", but the important bit that sometimes gets missed out is "in a vacuum".
If you want to see a very cool effect caused by the difference in the speed of light between material A and material B, look up Cherenkov radiation on the net, especially for pictures!
I always thought that was a cool step up from cold cathode lighting for a games rig, but the health and safety implications (not to mention getting raided by SO13 at 4am for being a terrorist implications) make it a little less attractive.
You;ve gotta admit tho - the cooling and visual benefits of dropping your rig in heavy water with some beta emmitters are definitely there...
Gravitic lenses caused by galaxies should be the most familiar, but even planets can cause the light path to curve.
Space-time is affected by mass - so another way of creating a light pulse would, I postulate, consist of a black-hole which can have its' mass altered.
Feed some light into the black hole at the right angle whilst adding sufficient mass to trap the light, and then simply remove some mass to release the light.
Wouldn't change the speed of the light, of course.
Simples*
Now is it worth patenting that idea I wonder?? hmm
ttfn
*Ok - there may be an element of sarcasm in there.
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