Invariant Subspaces for Commuting Operators on a Real Banach Space
Funkcionalʹnyj analiz i ego priloženiâ, Tome 52 (2018) no. 1, pp. 65-69
Voir la notice de l'article provenant de la source Math-Net.Ru
It is proved that the commutative algebra $\mathcal{A}$ of operators on a reflexive real Banach space has an invariant subspace if each operator $T\in\mathcal{A}$ satisfies the condition
$$
\|1-\varepsilon T^2\|_e\le 1+o(\varepsilon)\ \text{as}\ \varepsilon\searrow 0
$$
where $\|\cdot\|_e$ denotes the essential norm. This implies the existence of an invariant subspace for any commutative family of essentially self-adjoint operators on a real Hilbert space.
Keywords:
Banach space, algebra of operators, invariant subspace.
@article{FAA_2018_52_1_a6,
author = {V. I. Lomonosov and V. S. Shul'man},
title = {Invariant {Subspaces} for {Commuting} {Operators} on a {Real} {Banach} {Space}},
journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
pages = {65--69},
publisher = {mathdoc},
volume = {52},
number = {1},
year = {2018},
language = {ru},
url = {http://geodesic.mathdoc.fr/item/FAA_2018_52_1_a6/}
}
TY - JOUR AU - V. I. Lomonosov AU - V. S. Shul'man TI - Invariant Subspaces for Commuting Operators on a Real Banach Space JO - Funkcionalʹnyj analiz i ego priloženiâ PY - 2018 SP - 65 EP - 69 VL - 52 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/FAA_2018_52_1_a6/ LA - ru ID - FAA_2018_52_1_a6 ER -
V. I. Lomonosov; V. S. Shul'man. Invariant Subspaces for Commuting Operators on a Real Banach Space. Funkcionalʹnyj analiz i ego priloženiâ, Tome 52 (2018) no. 1, pp. 65-69. http://geodesic.mathdoc.fr/item/FAA_2018_52_1_a6/