We calculate the mixed tensor susceptibility of QCD vacuum in the framework of the global color symmetry model. In our calculation, the functional integration over gluon fields can be performed and the gluonic vacuum observable can be expressed in terms of the quark operators and the gluon propagator. The mixed tensor susceptibility was obtained with the subtraction of the perturbative contribu...

Let J = [O,TJ and F : C°(J) x C°(J) x lH'.--7 Ll(J) be an operator. Existence theorems for the functional differential equation (g(x'(t)))' = (F(x,x',x'(t)))(t) with functional boundary conditions generalizing the non-homogeneous Dirichlet boundary conditions and nonhomogeneous mixed boundary conditions are given. Existence results are proved by the Leray-Schauder degree theory under some sign ...

We say a functional equation () is stable if any function g satisfying the equation () approximatelyis near to true solution of (). Using xed point methods, we investigate approximately higherternary derivations in Banach ternary algebras via the Cauchy functional equationf(1x + 2y + 3z) = 1f(x) + 2f(y) + 3f(z) :