The median bubble size for a
region of space is defined as follows: Half the volume of the region is
contained in bubbles larger than the median size. I prefer to use
median rather mean, which is more difficult to define. If bubble
sizes are random, there might be so many very small ones that the mean
volume is very small. Also, it is difficult to decide if a small bubble
really is a bubble.
Observations
suggest that the laws of physics operate uniformly thruout our
universe. I believe this means that the ether is uniform, and the
median size of ether-foam bubbles is uniform within
the visible universe at all scales larger than a few bubbles across. I
speculate that significant variations of the median size may occur in
regions a few bubbles across.
I further speculate that the median bubble size of our ether foam is
roughly equal to the Planck length, about 10-35
m. This being the case, the median bubble volume is about 10-105
m3.
There
is also a median bubble size in the cosmic foam. This is approximately
10^24 m in diameter, which is roughly 1000 times the width of our
galaxy.