A normed vector space is said to be uniformly
convex if for sequences
,
, the assumptions
,
, and
together imply that
as
tends to infinity.
Such spaces are important in functional analysis. For example, the classical Banach-Saks theorem
can be generalized so that the desired conclusion holds in the case that is a Banach space whose conjugate
space (that is, the complex conjugate of the
dual vector space
) is uniformly convex.