This one: http://en.wikipedia.org/wiki/Cosmic_latte

heh. that's cute. i knew karl back in the day.

you could also say that it's the colour of the microwave background, which dominates the radiation in the universe (it's the "glow" left over from the big bang), however that's cooled so much that it's effectively black.

i'm not sure how they defined average to avoid coming out with black from that. would be worth checking the paper...

#FFF8E7 ... this is amazing, but also unnatural. What I mean is, how can this be an unbalanced thing? Why not perfect white or perfect black?

Because some stars emit more blue and some more red. Also you can't have 100% light in universe (without creating a black hole that is), so when you mix lights, you have to mix different colors as unbounded values and then divide by max to get some normalized representable rgb value with 100% luminosity. #FFxxxx means there is more red than other colors, but only a little more. If every frequency in visible light would have the same strength in resulting spectrum, you would have #FFFFFF.

If the entire universe is in one pixel, there is no single photon outside, so it is of course black! But moreover from a quantum mechanics point of view, if there is nobody is outside the entire universe, there is no one observing something from the universe, so maybe the universe doesn't exist...(see this as an inspirement: http://www.iafe.uba.ar/e2e/phys230/history/moon.pdf)

http://en.wikipedia.org/wiki/Eigengrau ?

I think either black when matter is put in or transparent when matter and anti-matter is put in.

it depends on which filter you are applying. But probably blue. Because of the big oceans we have.

haha, very fuuny

The entire universe is a pixel. You are inside it, what do you see when you look out to nothing?