On Sums of Projections
- Cite this article as:
- Kruglyak, S.A., Rabanovich, V.I. & Samoilenko, Y.S. Functional Analysis and Its Applications (2002) 36: 182. doi:10.1023/A:1020193804109
In the paper, for all n∈ℕ, we describe the set ∑n of all real numbers α admitting a collection of projections P1,...,Pn on a Hilbert space H such that ∑k=1nPk=α I (I is the identity operator on H) and study the problem to find all collections of this kind for a given α∈∑n.