2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/61609For all transcendental parameters, the irrational rotation algebra is shown to contain infinitely many C*-subalgebras satisfying the following properties. Each subalgebra is isomorphic to a direct sum of two matrix algebras of the same (perfect square) dimension; the Fourier transform maps each summand onto the other; the corresponding unit projection is approximately central; the compressions of the canonical generators of the irrational rotation algebra are approximately contained in the subalgebra.20 pagesOperator AlgebrasFunctional Analysis46L80, 46L40, 46L35text