First, let me distinguish Concrete Mathematics ( Mathematic branches that studies fixed structures ) from Abstract Mathematics ( branches that study classes of structures, such as algebra , topology, etc ).
Number theory studies fixed set(s) whose cardinality is at most of the reals ( but mainly of the naturals ).
Analysis studies fixed set(s) whose cardinality is at most the cardinality of the reals ( but mainly of the reals ).
Is there any actual concrete mathematics that is done under fixed set(s) of cardinality greater than the reals, in other words, is there any set with cardinality greater than the reals that is important enough to have its own discipline ?
Does anyone know why that's the case ?
P.S : Obviously, i'm not considering set theory as a possible option, since the sets there are not concrete, but abstract.
Thanks in advance