Zobrazeno 1 - 10
of 59
pro vyhledávání: '"Câmara, M. Cristina"'
Publikováno v:
JHEP06(2024)027
The Riemann-Hilbert approach, in conjunction with the canonical Wiener-Hopf factorisation of certain matrix functions called monodromy matrices, enables one to obtain explicit solutions to the non-linear field equations of some gravitational theories
Externí odkaz:
http://arxiv.org/abs/2404.03373
This paper considers paired operators in the context of the Lebesgue Hilbert space on the unit circle and its subspace, the Hardy space $H^2$. The kernels of such operators, together with their analytic projections, which are generalizations of Toepl
Externí odkaz:
http://arxiv.org/abs/2308.16644
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 commute, generalizations of the Brown--Halmos results for Toeplitz ope
Externí odkaz:
http://arxiv.org/abs/2304.07252
Publikováno v:
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences (2024)
Explicit solutions to the non-linear field equations of some gravitational theories can be obtained, by means of a Riemann-Hilbert approach, from a canonical Wiener-Hopf factorisation of certain matrix functions called monodromy matrices. In this pap
Externí odkaz:
http://arxiv.org/abs/2211.01702
Autor:
Câmara, M. Cristina, Krejcirik, David
Publikováno v:
Anal. Math. Phys. 13 (2023), art. no. 6
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 extension theory, refined polar and singular-value decompositions, and antili
Externí odkaz:
http://arxiv.org/abs/2208.05739
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 truncated operators is investigated. Most of the results obtained are ne
Externí odkaz:
http://arxiv.org/abs/2203.09265
Autor:
Câmara, M. Cristina1 cristina.camara@tecnico.ulisboa.pt, Kliś-Garlicka, Kamila2 rmklis@cyfronet.pl, Ptak, Marek2 rmptak@cyf-kr.edu.pl
Publikováno v:
Opuscula Mathematica. 2024, Vol. 44 Issue 3, p341-357. 17p.
We relate dual-band general Toeplitz operators to block truncated Toeplitz operators and, via equivalence after extension, with Toeplitz operators with $4 \times 4$ matrix symbols. We discuss their norm, their kernel, Fredhomlness, invertibility and
Externí odkaz:
http://arxiv.org/abs/2012.14725
Following Beurling's theorem the natural compressions of the multiplication operator in the classical $L^2$ space are compressions to model spaces and to their orthogonal complements. Two possibly different model spaces are considered hence asymmetri
Externí odkaz:
http://arxiv.org/abs/2012.05330
We consider kernels of unbounded Toeplitz operators in $H^p(\mathbb C^+)$ in terms of a factorization of their symbols. We study the existence of a minimal Toeplitz kernel containing a given function in $H^p(\mathbb C^+)$, we describe the kernels of
Externí odkaz:
http://arxiv.org/abs/2004.09985