Invariant projections, hyperinvariant subspaces, and transitive algebras
What the paper claims, in its own words
Constructs a nonzero norm-quasinilpotent operator on every infinite-dimensional separable complex Hilbert space with no nonzero proper closed subspace invariant under every commuting operator. The construction also gives operators with no nontrivial invariant projection in the hyperfinite type II1 factor.
The plain-language explainer for this entry is still coming.
The original papers (2)
- Invariant-projection counterexamples for every irrational rotation (PDF, opens in a new tab) September 27, 2026
- Backward intertwiners and a transitive commutant (PDF, opens in a new tab) September 27, 2026 Formal proof listed