Quote by Mentz114
A.T.:
I'm looking at a metric which when r = 0 goes to ds^2 = dr^2  c^2dt^2. I interpret this as 'flat', but I could be wrong.

The metric ds^2 = dr^2  c^2dt^2 is flat, it's the same with metric at infinity, but it can't be the metric in the cavity. Since a clock in the cavity run slower than a clock at infinity