Semiclosed multivalued projections
M. Laura Arias, Maximiliano Contino, Alejandra Maestripieri, Stefania A. M. Marcantognini · Linear Algebra and its Applications · 2023
A multivalued projection is an idempotent linear relation with invariant domain. We characterize multivalued projections that are operator ranges (called semiclosed) and provide several formulae of them. Moreover, we study the decomposability and continuity of multivalued projections, and describe nilpotent relations.