Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

Isn't the issue one of lumens? The light from a star is inversely quadratically related to its distance. Assuming a random distribution of stars across a ring or plate in 3D space we should expect the quadratically growing number of stars for the incremental space. The two cancel and it becomes a ratio of the average brightness of a star (bright) versus the density of stars in space (super sparse).


Imagine an infinite series of nested hollow shells of equal thickness around Earth.

The number of stars in each shell is quadratic relative to the radius. The brightness of each star is inversely quadratic relative to the radius of the shell. Thus, each shell has a constant total brightness, as perceived from Earth. An infinite number of these shells add up to infinite brightness.


I'm not quite following. The light in each "shell" continues to dissipate in an inversely quadratic method from the shells distance from earth, no? It would help if I had this drawn out.


No, the total light in each spherical "shell" is the same as every other shell.

Stars that are 20 light-years away are 4x dimmer than stars 10 light-years away. But there are 4x more stars 20 light-years away than 10 light-years away. As you go outward from Earth, the stars get dimmer and more numerous, but these balance each other, and the infinite sum is 1 + 1 + 1 + ...

(This is no chance happening; regardless of the # of spatial dimensions the universe has, this relationship holds true.)




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: