DOI: 10.68381/jca03023 ISSN: 0944-6532

A New Tool in the Theory of Integral Representation

R. Becker

Let

E E
be a Hausdorff locally convex space,
E^\prime E ′
its dual, and
X\subset E X ⊂ E
a proper convex cone, not necessarily closed. Recall that an open ray
\delta δ
of
X X
is said to be extreme if
(x \in \delta ( x ∈ δ
and
x = y +z x = y + z
with
y,z \in X \setminus 0) y , z ∈ X ∖ 0 )
implies
(y,z \in \delta) ( y , z ∈ δ )
. We denote by
\mathcal{E}(X) E ( X )
the union of all extreme open rays of
X X
. We say that
X X
has the property of integral representation if for each
x \in X x ∈ X
there is a positive Radon measure
m m
on
\mathcal{E}(X) E ( X )
such that each
f \in E^\prime f ∈ E ′
is
m m
-integrable and
m(f)=f(x) m ( f ) = f ( x )
. Recently E. Thomas ["Integral representations in conuclear cones", J. Convex Analysis 1/2 (1994) 225–258] proved a theorem of integral representation for a class of convex cones, called conuclear. The aim of this work is to give a quite different presentation of his results, with the help of other tools, one of which is new (the pseudo-caps), allowing to avoid some of his hypotheses.