Generalized parton distributions and strong forces inside nucleons and nuclei

We argue that generalized parton distributions (GPDs), accessible in hard exclusive processes, carry information about the spatial distribution of forces experienced by quarks and gluons inside hadrons. This way the measurements of hard exclusive processes open a possibility for direct measurements of strong forces in different parts of nucleons and nuclei. Also such studies open avenue for addressing questions of the properties of the quark (gluon) matter inside hadrons and nuclei. We give a simple example of relations between GPDs and properties of nuclear matter in finite nuclei. (C) 2003 Published by Elsevier Science B.V.