Mr. Maniac
"blacklight" is actually kind of purpleish white, the reason they call it blacklight is that it doesn't light things up, exept light colors (making white shirts glow, for example)
And the problem with the solution of the absence is the fact that, to absorb light, you need atoms, you need a material, and with that, a mass. (because emmision and absorbion of light is based on the changing energy levels of electrons in atoms, a change in energy of 2 eV gives a redish color, 2 MeV gives gamma rays I believe)
Anyway, since the blade of a saber is pure energy, it consists of fotons emitted from the saber. Fotons with the enery 2 eV give a red light, but they cannot absorb light...just "show" it. Making a black blade impossible
which would mean a lightsaber, in the core, is a concentrated ray of fotons in all colors (white), on the edge it's of one color (the blade color). Only, since they're concentrated in a beam, you shouldn't see them (because they don't escape in all directions), unless the fotons are reflected by smoke and all, like with a laser (and the edge between the core and blade wouldn't be that sharp, it would likely be a monotone color blade, light with the tone of the blade color)
edit: blacklight is ultraviolet, the works: http://electronics.howstuffworks.com/question59.htm
And the problem with the solution of the absence is the fact that, to absorb light, you need atoms, you need a material, and with that, a mass. (because emmision and absorbion of light is based on the changing energy levels of electrons in atoms, a change in energy of 2 eV gives a redish color, 2 MeV gives gamma rays I believe)
Anyway, since the blade of a saber is pure energy, it consists of fotons emitted from the saber. Fotons with the enery 2 eV give a red light, but they cannot absorb light...just "show" it. Making a black blade impossible
which would mean a lightsaber, in the core, is a concentrated ray of fotons in all colors (white), on the edge it's of one color (the blade color). Only, since they're concentrated in a beam, you shouldn't see them (because they don't escape in all directions), unless the fotons are reflected by smoke and all, like with a laser (and the edge between the core and blade wouldn't be that sharp, it would likely be a monotone color blade, light with the tone of the blade color)
edit: blacklight is ultraviolet, the works: http://electronics.howstuffworks.com/question59.htm
