Quasicontraction semigroup

In mathematical analysis, a C₀-semigroup Γ(t), t ≥ 0, is called a quasicontraction semigroup if there is a constant ω such that ||Γ(t)|| ≤ exp(ωt) for all t ≥ 0. Γ(t) is called a contraction semigroup if ||Γ(t)|| ≤ 1 for all t ≥ 0.

See also

• Contraction (operator theory)
• Hille-Yosida theorem
• Lumer-Phillips theorem

References

• Renardy, Michael; Rogers, Robert C. (2004). An introduction to partial differential equations. Texts in Applied Mathematics 13 (Second ed.). New York: Springer-Verlag. p. xiv+434. ISBN 0-387-00444-0.  MR 2028503