13 citations · 30 across the 12 of their papers we have counts for
18 papers
Riemann-Hilbert problems, Toeplitz operators and ergosurfaces
M. Cristina Câmara, Gabriel Lopes Cardoso
The Riemann-Hilbert approach, in conjunction with the canonical Wiener-Hopf factorisation of certain matrix functions called monodromy matrices, enables one to obtain explicit solu…
Paired kernels and their applications
M. Cristina Câmara, Jonathan R. Partington
This paper considers paired operators in the context of the Lebesgue Hilbert space on the unit circle and its subspace, the Hardy space . The kernels of such operators, togeth…
Paired operators and paired kernels
M. Cristina Câmara, André Guimarães, Jonathan R. Partington
This paper is concerned with paired operators in the context of the Lebesgue Hilbert space on the unit circle and its subspace, the Hardy space. By considering when such operators…
Complex-self-adjointness
M. Cristina Câmara, David Krejcirik
We develop the concept of operators in Hilbert spaces which are similar to their adjoints via antiunitary operators, the latter being not necessarily involutive. We discuss extensi…
Shift invariance and reflexivity of compressions of multiplication operators
M. Cristina Câmara, Kamila Kliś-Garlicka, Bartosz Łanucha +1
The property of being shift invariant and being reflexive or transitive in the case of the space of (asymmetric) truncated Toeplitz operators, and the space of (asymmetric) dual tr…
Intertwining property for compressions of multiplication operators
M. Cristina Câmara, Kamila Kliś--Garlicka, Bartosz Łanucha +1
Following Beurling's theorem the natural compressions of the multiplication operator in the classical space are compressions to model spaces and to their orthogonal complemen…
Dual-band general Toeplitz operators
M. Cristina Câmara, Ryan O'Loughlin, Jonathan R. Partington
We relate dual-band general Toeplitz operators to block truncated Toeplitz operators and, via equivalence after extension, with Toeplitz operators with matrix symbols.…
Kernels of unbounded Toeplitz operators and factorization of symbols
M. Cristina Câmara, M. Teresa Malheiro, Jonathan R. Partington
We consider kernels of unbounded Toeplitz operators in in terms of a factorization of their symbols. We study the existence of a minimal Toeplitz kernel containi…
The dual of the compressed shift
M. C. Camara, W. T. Ross
For an inner function u we discuss the dual operator for the well-known compressed shift. We establish conditions for two dual compressed shifts to be unitarily equivalent/similar…
Conjugations in
M. Cristina Câmara, Kamila Kliś--Garlicka, Bartosz Łanucha +1
Conjugations commuting with and intertwining and in , where is a Hilbert space, are characterize…
Invertibility, Fredholmness and kernels of dual truncated Toeplitz operators
M. Cristina Câmara, Kamila Kliś-Garlicka, Bartosz Łanucha +1
Asymmetric dual truncated Toeplitz operators acting between the orthogonal complements of two (eventually different) model spaces are introduced and studied. They are shown to be e…
Conjugations in and their invariants
M. Cristina Câmara, Kamila Kliś--Garlicka, Bartosz Łanucha +1
Conjugations in space of the unit circle commuting with multiplication by or intertwining multiplications by and are characterized. We also study their behav…
Weyl metrics and Wiener-Hopf factorization
P. Aniceto, M. C. Câmara, G. L. Cardoso +1
We consider the Riemann-Hilbert factorization approach to the construction of Weyl metrics in four space-time dimensions. We present, for the first time, a rigorous proof of the re…
A Riemann-Hilbert approach to rotating attractors
M. C. Camara, G. L. Cardoso, T. Mohaupt +1
We construct rotating extremal black hole and attractor solutions in gravity theories by solving a Riemann-Hilbert problem associated with the Breitenlohner-Maison linear system. B…
Model spaces and Toeplitz kernels in reflexive Hardy spaces
M. C. Câmara, M. T. Malheiro, J. R. Partington
This paper considers model spaces in an setting. The existence of unbounded functions and the characterisation of maximal functions in a model space are studied, and decompos…
Asymmetric truncated Toeplitz operators and Toeplitz operators with matrix symbol
M. Cristina Câmara, Jonathan R. Partington
Truncated Toeplitz operators and their asymmetric versions are studied in the context of the Hardy space of the half-plane for . It is shown that they are equival…
One sided invertibility of matrices over commutative rings, corona problems, and Toeplitz operators with matrix symbols
Maria Cristina Câmara, Leiba Rodman, Ilya M. Spitkovsky
Conditions are established under which Fredholmness, Coburn's property and one- or two-sided invertibility are shared by a Toeplitz operator with matrix symbol and the Toeplitz…
Factorization, Riemann-Hilbert problems and the corona problem
M. C. Camara, C. Diogo, Yu. I. Karlovich +1
The solvability of the Riemann-Hilbert boundary value problem on the real line is described in the case when its matrix coefficient admits a Wiener-Hopf type factorization with bou…