Jump to content

Strongly measurable function

From Wikipedia, the free encyclopedia
This is an old revision of this page, as edited by 1234qwer1234qwer4 (talk | contribs) at 01:09, 4 January 2021 (Added link). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Strong measurability has a number of different meanings, some of which are explained below.

Values in Banach spaces

For a function f with values in a Banach space (or Fréchet space), strong measurability usually means Bochner measurability.

However, if the values of f lie in the space of continuous linear operators from X to Y, then often strong measurability means that the operator f(x) is Bochner measurable for each , whereas the Bochner measurability of f is called uniform measurability (cf. "uniformly continuous" vs. "strongly continuous").[clarification needed]

Semigroups

A semigroup of linear operators can be strongly measurable yet not strongly continuous.[1] It is uniformly measurable if and only if it is uniformly continuous, i.e., if and only if its generator is bounded.

References

  1. ^ Example 6.1.10 in Linear Operators and Their Spectra, Cambridge University Press (2007) by E.B.Davies