Superquadratic functions and the refinement of some classical inequalities
Abstract
Convexity and inequalities have proved to be useful in many branches of mathematics
such as functional analysis, theory of di fferential and integral equations,
optimisation, interpolation, harmonic analysis and probability theory. They have
useful applications also in mechanics, physics, economics and other sciences.
Over the last 80 years, inequalities have seen a lot of interest from researchers,
which has led to a great number of recent published books and articles. Thus,
the theory of inequalities has developed into an independent branch or area of
mathematics.
This thesis is dedicated to a new refi nement of Jensen's inequality, which permits
the use of non-continuous functions considered to be superquadratic.
A re finement of Minkowski's inequality is established as a direct consequence of
our refi ned Jensen's inequality.
A lower bound for Young's inequality is also established as an application of superquadratic
functions.
Finally a re finement of the local submean inequality for subharmonic functions
is also presented as an application of superquadratic functions.
Description
A Thesis submitted to the Department of Mathematics, College of Science
in partial ful lment of the requirements for the degree of Doctor of Philosophy,