\gimelThe symbol \gimel is used to represent the gimel function or cardinal number in set theory. It is a Hebrew letter that is often used in mathematical contexts to denote certain types of infinite cardinals.
Gimel function applied to an ordinal \alpha
\gimel_\alphaThe smallest infinite cardinal, often associated with the set of natural numbers
\gimel_0 = \aleph_0The cardinality of the continuum, representing the set of real numbers
\gimel_1 = 2^{\aleph_0}