The notion of singular quadratic form appears in mathematical physics as a tool for the investigation of formal expressions corresponding to perturbations devoi

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The present book is the second of the two volume Proceedings of the Mark Krein International Conference on Operator Theory and Applications. This conference, wh

This volume and Stochastic Processes, Physics and Geometry: New Interplays I present state-of-the-art research currently unfolding at the interface between math