Lower semicontinuous convex functions

Part of the Lecture Notes in Mathematics book series (LNM, volume 1364)


Our differentiability results for convex functions made heavy and consistent use of continuity, but in both the theoretical and applied aspects of convex functions, it is sometimes desirable to weaken this hypothesis. Lower semicontinuity is precisely what is needed. Uncomfortable as it may seem at first, the subject is best treated by introducing the seeming complication of admitting extended real-valued functions, that is, functions with values in R ∪ {00}. We adopt the conventions that
$$ r \cdot \infty = \infty and \left( { - r} \right) \cdot \infty = - \infty if r > 0, and r \pm \infty for all r \in R. $$
(We won’t have occasion to worry about ∞ — ∞ or 0 · ∞.)


Banach Space Convex Function Monotone Operator Nonempty Closed Convex Subset Support Point 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Personalised recommendations