Limits on Light Density

Most recent answer: 06/03/2011

Q:
is there a limit to how much light there can be in a space? if there is what is that limit?
- Cole L. (age 16)
Oakville, ON, Canada
A:
There's a limit on the total energy density in any region, including light energy. Too much energy causes things to collapse into black holes.  Roughly speaking, in a region with radius R, the energy can't be more than ~Rc4/G where c is the speed of light and G is Newton's gravitational constant.

Mike W.

(published on 06/03/2011)