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Related papers: Almost invariant subspaces and operators

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We give a streamlined proof of the multiplicative ergodic theorem for quasi-compact operators on Banach spaces with a separable dual.

Dynamical Systems · Mathematics 2016-12-05 Cecilia González-Tokman , Anthony Quas

We review recent work connected with the invariant subspace problem for operators, in particular new developments in the last 15 years. In particular, we include discussions of almost-invariant subspaces, universal operators, specific…

Functional Analysis · Mathematics 2025-07-30 I. Chalendar , J. R. Partington

We develop real Paley-Wiener theorems for classes ${\mathcal S}_\omega$ of ultradifferentiable functions and related $L^{p}$-spaces in the spirit of Bang and Andersen for the Schwartz class. We introduce results of this type for the…

Functional Analysis · Mathematics 2023-04-18 Chiara Boiti , David Jornet , Alessandro Oliaro

This paper explores the interactions of absolute continuity of the (quasi)norm with the concepts that are fundamental in the theory of rearrangement-invariant (quasi-)Banach function spaces, such as the Luxemburg representation or the…

Functional Analysis · Mathematics 2025-10-15 Dalimil Peša

We show that any bounded operator $T$ on a separable, reflexive, infinite-dimensional Banach space $X$ admits a rank one perturbation which has an invariant subspace of infinite dimension and codimension. In the non-reflexive spaces, we…

Functional Analysis · Mathematics 2012-08-30 Alexey I. Popov , Adi Tcaciuc

In this paper, we prove the Mohebi-Radjabalipour Conjecture under a little additional condition, and obtain a new invariant subspace theorem for subdecomposable operators. Our main results contain known results in this topic as special…

Functional Analysis · Mathematics 2019-01-29 Junfeng Liu , Songxiao Li

Almost uniform version of noncommutative Wiener-Wintner ergodic theorem and its extension to Besicovitch weights are proved.

Functional Analysis · Mathematics 2020-12-03 Vladimir Chilin , Semyon Litvinov

We prove various results on the size and structure of subsets of vector spaces over finite fields which, in some sense, have too many mutually orthogonal pairs of vectors. In particular, we obtain sharp finite field variants of a theorem of…

Combinatorics · Mathematics 2022-05-05 Ali Mohammadi , Giorgis Petridis

We develop a Galois theory of commutative rings under actions of finite inverse semigroups. We present equivalences for the definition of Galois extension as well as a Galois correspondence theorem. We also show how the theory behaves in…

Rings and Algebras · Mathematics 2025-01-03 Wesley G. Lautenschlaeger , Thaísa Tamusiunas

We exploit the Galois symmetries of the little disks operads to show that many differentials in the Goodwillie-Weiss spectral sequences approximating the homology and homotopy of knot spaces vanish at a prime $p$. Combined with recent…

Algebraic Topology · Mathematics 2025-03-25 Pedro Boavida de Brito , Geoffroy Horel

In this paper we prove off-diagonal, limited range, multilinear, vector-valued, and two-weight versions of the Rubio de Francia extrapolation theorem in general quasi-Banach function spaces. We prove mapping properties of the generalization…

Classical Analysis and ODEs · Mathematics 2024-09-16 Zoe Nieraeth

Given an arbitrary finite set of data F= {f_1,..., f_m} in L2(Rd) we prove the existence and show how to construct a "small shift invariant space" that is "closest" to the data F over certain class of closed subspaces of L2(Rd). The…

Functional Analysis · Mathematics 2019-01-09 Carlos Cabrelli , Carolina A. Mosquera

Let $M$ be a Hopf--von Neuman algebra with the predual $M_*$ and $WAP(M)$ the subspace in $M$ composed of weakly almost periodic functionals on $M_*$. The main example of such an algebra is $M=L^\infty(\mathbb G)$ for a locally compact…

Operator Algebras · Mathematics 2022-06-28 Yulia Kuznetsova

This article describes Hilbert spaces contractively contained in certain reproducing kernel Hilbert spaces of analytic functions on the open unit disc which are nearly invariant under division by an inner function. We extend Hitt's theorem…

Functional Analysis · Mathematics 2025-02-19 Arshad Khan , Sneh Lata , Dinesh Singh

A simple proof is provided to show that any bounded normal operator on a real Hilbert space is orthogonally equivalent to its transpose(adjoint). A structure theorem for invertible skew-symmetric operators, which is analogous to the finite…

Spectral Theory · Mathematics 2020-04-21 B V Rajarama Bhat , Tiju Cherian John

In this paper we develop a strategy and some technical tools for proving the Andre-Oort conjecture. We give lower bounds for the degrees of Galois orbits of geometric components of special subvarieties of Shimura varieties, assuming the…

Number Theory · Mathematics 2013-09-12 Emmanuel Ullmo , Andrei Yafaev

We discuss the concept of invariant subspaces for unbounded linear operators, point out some shortcomings of known definitions, and propose our own.

Functional Analysis · Mathematics 2025-05-13 M. I. Belishev , S. A. Simonov

An effective algorithm of determining Gromov--Witten invariants of smooth hypersurfaces in any genus (subject to a degree bound) from Gromov--Witten invariants of the ambient space is proposed. The Appendix is joint with E. Schulte-Geers.

Algebraic Geometry · Mathematics 2021-08-05 Honglu Fan , Yuan-Pin Lee

A characterization of finitely generated shift-invariant subspaces is given when generators are g-minimal. An algorithm is given for the determination of the coefficients in the well known representation of the Fourier transform of an…

Classical Analysis and ODEs · Mathematics 2019-06-18 K. S. Kazarian

In this article we study invariance properties of shift-invariant spaces in higher dimensions. We state and prove several necessary and sufficient conditions for a shift-invariant space to be invariant under a given closed subgroup of…

Classical Analysis and ODEs · Mathematics 2010-02-08 Magalí Anastasio , Carlos Cabrelli , Victoria Paternostro