[Retric]

Assuming the speed of light is absolute the odds of finding a civilization is vastly diminished. EX: Assume they are 1/2 the age of the universe and expand at the speed of light. From the 46.5 billion light-year radius observable sphere due to expansion. They have a bubble ~1/4 the size of the observable universe in size (less time for expansion of space/time). But, that's only ~(1/4)^3 = ~1/64th chance we see this super civilization even with such optimistic estimates.

Start plugging in more reasonable numbers for expansion say a smaller chunk of c and reasonable assumptions of requiring old rocky planets etc, and there could be 10^10th such civilizations and we just can't see them.