Approximately Linear Functionals on Hilbert Spaces
✍ Scribed by Peter Šemrl
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 147 KB
- Volume
- 226
- Category
- Article
- ISSN
- 0022-247X
No coin nor oath required. For personal study only.
✦ Synopsis
Let H be a real or complex Hilbert space, and let ) 0. A functional f on H is < Ž . Ž . Ž .< called an -approximately linear functional if f x q y y f x y f y F Ž< < 5 5 < < 5 5.
x q y for all scalars , and all vectors x, y g H. If such a functional f is bounded then there exists a continuous linear functional g on H such < Ž . Ž .< 5 5 that f x y g x F 37 x for every x g H.
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