What also surprised me is that the speed difference depending on medium is actually quite substantial. For example, glass has a refractive index of about 1.5.
So, the speed of light in glass is c/1.5 ≈ 200.000 km/s, i.e. 66% of the speed of light in vacuum.
That is the very definition of colour. The part of the electromagnetic spectrum that we can see. The rest of the scale includes infrared, gamma or X-ray. If you want, you can call them invisible colours - or you can call green superhighultraviolet.
In everyday context yes, but it’s pretty common to use “colour” to refer to frequency outside the visible range, and it’s interesting to consider what interesting “colours” we are missing out on because they’re outside our visible range.
Silver/grey implies even response across the spectrum, and is the normal expectation.
If we couldn’t see yellow (red/green) then gold would presumably look silver to us, so are there silver/grey metals that would have an interesting colour if only we could see it?
Color is visible light in the human spectrum. We would say they see in the ultraviolet or infrared spectrum. Non human animals don’t use the literature so it’s designed with human perception in mind.
I wonder if there are some metals that appear grey to us but actually have a color, we just don’t see it because it’s outside our visible spectrum
Uranium is neon blue:
So that got me curious, and found this
Somehow I’ve gone through decades of life without knowing this…
What also surprised me is that the speed difference depending on medium is actually quite substantial. For example, glass has a refractive index of about 1.5.
So, the speed of light in glass is c/1.5 ≈ 200.000 km/s, i.e. 66% of the speed of light in vacuum.
uranium itself isn’t, anything will glow that colour if it undergoes nuclear fission underwater.
That is the very definition of colour. The part of the electromagnetic spectrum that we can see. The rest of the scale includes infrared, gamma or X-ray. If you want, you can call them invisible colours - or you can call green superhighultraviolet.
In everyday context yes, but it’s pretty common to use “colour” to refer to frequency outside the visible range, and it’s interesting to consider what interesting “colours” we are missing out on because they’re outside our visible range.
Silver/grey implies even response across the spectrum, and is the normal expectation.
If we couldn’t see yellow (red/green) then gold would presumably look silver to us, so are there silver/grey metals that would have an interesting colour if only we could see it?
If a bee sees a color we cannot, it would be pretty silly to insist it’s not a color on the basis of us being unable to see it, wouldn’t it?
Are there creatures that see radio? (Which I suppose is pretty general.) if so, they must hate us.
Color is visible light in the human spectrum. We would say they see in the ultraviolet or infrared spectrum. Non human animals don’t use the literature so it’s designed with human perception in mind.
Well infrared goes the other direction. Along with radio.