[OT] Power over radio is it a true thing or just a myth ?

[Shachar Shemesh]

Please excuse me for answering a humorous post seriously.

Gilad Ben-Yossef wrote:
>
> Despite popular belief, the speed of light is only fixed in vacuum and 
> scientists long acknowledged the fact that  light may travels in 
> different and lesser speeds when going through different materials, 
> such as air, or water.
Again, not precisely accurate.

While light will, indeed, travel slower through any material denser than 
vacuum, this is not what the term "speed of light" refers to. To the 
best of my knowledge, "speed of light" refers to a basic property of the 
universe (how fast will any change of any field propagate), and that is 
the property that goes into the time warping formulas (the famous "c" in 
Lorentz transformation). Just because light travels through glass at 30% 
less speed does not mean you have to aim 30% lower if you want to freeze 
time (unless, and this is something I'm not 100% clear about, YOU are 
traveling through glass as well).

> 88 miles per hour, it would seem, is the speed of light as it travels 
> through Hollywood movies.
At least that one seems pretty accurate. This also explains why pretty 
much anything looks different when viewed through the filters of a 
Holywood movie. The huge refraction coefficient acts like lens, only 
much more powerful.

Shachar

-- 
Shachar Shemesh
Lingnu Open Source Consulting Ltd.
http://www.lingnu.com

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