contraction semigroup

contraction semigroup

[kən′trak·shən ′sem·i‚grüp]
(mathematics)
A strongly continuous semigroup all of whose elements have norms which are equal to or less than a constant which is, in turn, less than 1.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.