Results 31 to 40 of about 485,398 (210)

Fredholm operators on C*-algebras [PDF]

Acta Scientiarum Mathematicarum, 2017
The aim of this note is to generalize the notion of Fredholm operator to an arbitrary $C^*$-algebra. Namely, we define "finite type" elements in an axiomatic way, and also we define Fredholm type element $a$ as such element of a given $C^*$-algebra for which there are finite type elements $p$ and $q$ such that $(1-q)a(1-p)$ is "invertible".
Kečkić, Dragoljub J., Lazović, Zlatko
openaire   +2 more sources

On Solvability in the Class of Distributions of Degenerate Integro-Differential Equations in Banach Spaces

Известия Иркутского государственного университета: Серия "Математика", 2020
The paper considers a new approach to constructing generalized solutions of degenerate integro-differential equations convolution type in Banach spaces.
M.V. Falaleev
doaj   +1 more source

THE TWO-SIDED ESTIMATES OF THE FREDHOLM RADIUS AND COMPACTNESS CONDITIONS FOR THE OPERATOR ASSOCIATED WITH A SECOND-ORDER DIFFERENTIAL EQUATION

Вестник КазНУ. Серия математика, механика, информатика, 2021
In this paper we consider the properties of the resolvent of a linear operator corresponding to a degenerate singular second-order differential equation with variable coefficients, considered in the Lebesgue space.
K. N. Ospanov, A. N. Yesbayev
doaj   +1 more source

$C_{0}$-Fredholm operators. IV [PDF]

Publicacions Matemàtiques, 1983
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +6 more sources

A Toeplitz-like operator with rational symbol having poles on the unit circle I: Fredholm properties [PDF]

, 2018
In this paper a definition is given for an unbounded Toeplitzlike operator with rational symbol which has poles on the unit circle. It is shown that the operator is Fredholm if and only if the symbol has no zeroes on the unit circle, and a formula for ...
Jaftha, J., Groenewald, G. J., G. J. Groenewald, A. C. M. Ran, Ran, A.C.M., Ran, A. C.M.; id_orcid, Groenewald, G.J., J. Jaftha, ter Horst, S., S. ter Horst   +9 more
core   +1 more source

On the solvability of the tracking problem in the optimization of the thermal process by moving point controls

Қарағанды университетінің хабаршысы. Математика сериясы, 2021
In the present article we investigate problems of tracking in the moving point control of thermal processes described by Fredholm integro-differential equations in partial derivatives with the Fredholm integral operator, in the case when the functions ...
A. Kerimbekov, A.T. Ermekbaeva, E. Seidakmat kyzy   +2 more
doaj   +1 more source

The time-dependent correlation function of the Jordan-Wigner operator as a Fredholm determinant

, 2009
We calculate a correlation function of the Jordan-Wigner operator in a class of free-fermion models formulated on an infinite one-dimensional lattice. We represent this function in terms of the determinant of an integrable Fredholm operator, convenient ...
Giamarchi, T., Zvonarev, M. B., Cheianov, Vadim   +2 more
core   +5 more sources

A Simple Proof of the Fredholm Alternative and a Characterization of the Fredholm Operators [PDF]

The American Mathematical Monthly, 2001
Let $A$ be a linear bounded operator in a Hilbert space $H$, $N(A)$ and $R(A)$ its null-space and range, and $A^*$ its adjoint.
openaire   +3 more sources

Block Toeplitz operators with frequency-modulated semi-almost periodic symbols

International Journal of Mathematics and Mathematical Sciences, 2003
This paper is concerned with the influence of frequency modulation on the semi-Fredholm properties of Toeplitz operators with oscillating matrix symbols.
A. Böttcher, S. Grudsky, I. Spitkovsky
doaj   +1 more source

Left and Right B-Fredholm Operators

Ukrainian Mathematical Journal, 2022
UDC 517.9 We introduce the families of left and right B-Fredholm operators in Banach space, realize their stabilization with the help of finite-rank operators, and  prove a spectral mapping theorem for the left and right B-Fredholm operators.
Abdmouleh, F., Lakhal, T. Ben
openaire   +2 more sources