> it doesn't make sense to me how something could be described as infinite (density) and finite (time) at the same time. The sequence A_n = 2-n = 1, 1/2, 1/4,

> it doesn't make sense to me how something could be described as infinite (density) and finite (time) at the same time. The sequence A_n = 2-n = 1, 1/2, 1/4, ..., has infinitely many terms, yet a finite sum 2. Different properties of a thing are different after all.