EXISTENCE THEOREMS FOR GENERALIZED NONLINEAR QUADRATIC INTEGRAL EQUATIONS VIA A NEW FIXED POINT RESULT

摘要

The existence of L~2-nonnegative solutions for nonlinear quadratic integral equations on a bounded closed interval is investigated. Two existence results for different classes of functions are shown. As a consequence an existence theorem for the Chandrasekhar integral quadratic equation, well-known in theory of radiative transfer, is obtained. The aim is achieved by means of a new fixed point theorem for multimaps in locally convex linear topological spaces.