unit sphere

(redirected from Closed unit ball)

unit sphere

[′yü·nət ′sfir]
(mathematics)
The set of points in three-space (more generally n-space) which are precisely one unit distance from the origin.
References in periodicals archive ?
Nygaard and Werner [10] showed that in every infinite-dimensional uniform algebra, every nonempty relatively weakly open subset of its closed unit ball has diameter 2.
Let BX and SX denote its closed unit ball and its unit sphere, respectively.