Why do cosmologists consider the cosmos infinite?
I am reviewing to books on Infinity I found interesting.
Infinity by A. W. Moore (1993) is a difficult read and approaches Infinity from a more philosophical agenda. It contains talks and essays from different authors over the last 40 years or so.
Infinity and the Mind by Rudy Rucker (1995) Easier to read and more current in many ways than the Moore compilation. It is well illustrated and more for the well educated general public.
From page 15 to 24 he introduces the concept of spatial infinities, which would be potential infinities as opposed to actual infinities.
I will post more from these two references.