Results 11 to 20 of about 40 (40)
The Cayley transform of Banach algebras
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 7, Page 427-428, 2002., 2002 The main result of Haynes (1991) is that a square matrix is convergent (limn→∞Dn = 0) if and only if it is the Cayley transform CA = (I−A)−1(I + A) of a stable matrix A. In this note, we show, with a simple proof, that the above is true in a much more general setting of complex Banach algebras.
Zhidong Pan
wiley +1 more source
Continuity and general perturbation of the Drazin inverse for closed linear operators
Abstract and Applied Analysis, Volume 7, Issue 6, Page 335-347, 2002., 2002 We study perturbations and continuity of the Drazin inverse of a closed linear operator A and obtain explicit error estimates in terms of the gap between closed operators and the gap between ranges and nullspaces of operators. The results are used to derive a theorem on the continuity of the Drazin inverse for closed operators and to describe the ...
N. Castro González +2 more
wiley +1 more source
Regularized functional calculi, semigroups, and cosine functions for pseudodifferential operators
Abstract and Applied Analysis, Volume 2, Issue 1-2, Page 121-136, 1997., 1997 Let iAj(1 ≤ j ≤ n) be generators of commuting bounded strongly continuous groups, A ≡ (A1, A2, …, An). We show that, when f has sufficiently many polynomially bounded derivatives, then there exist k, r > 0 such that f(A) has a ‐regularized BCk(f(Rn)) functional calculus.
Ralph Delaubenfels, Yansong Lei
wiley +1 more source
Fractional powers of non‐negative operators in Fréchet spaces
, 1988 International Journal of Mathematics and Mathematical Sciences, Volume 12, Issue 2, Page 309-320, 1989.
C. Martinez, M. Sanz, V. Calvo
wiley +1 more source
Soluciones explícitas de ecuaciones diferenciales matriciales con coeficientes variables
, 2009 La resolución de sistemas de ecuaciones diferenciales de orden superior suele apoyarse en la consideración de un sistema ampliado de primer orden. Este enfoque clásico presenta dos inconvenientes.
Company Rossi, Rafael
core +1 more source
Fractional Powers of Almost Non-Negative Operators [PDF]
, 2005 Mathematics Subject Classification: Primary 47A60, 47D06.In this paper, we extend the theory of complex powers of operators to a class of operators in Banach spaces whose spectrum lies in C \ ]−∞, 0[ and whose resolvent satisfies an estimate ||(λ + A ...
Martínez, Celso +2 more
core
, 2007 We give a minimal and maximal description in the sense of AronszajnGagliardo for the real methods in the case of n-tuple of quasi-Banach.
S M S Modarres, Z Ghorbani
core
On spatial Gevrey regularity for some strongly dissipative second order evolution equations
, 2019 Let A be a positive self-adjoint linear operator acting on a real Hilbert space H and α, c be positive constants. We show that all solutions of the evolution equation u" + Au + c A^α u' = 0 with u(0) ∈ D( A_1/2), u (0) ∈ H belong for all t > 0 to the ...
Haraux, Alain, Otani, Mitsuharu
core
Global well-posedness and interior regularity of 2D Navier-Stokes equations with stochastic boundary conditions. [PDF]
Math AnnAgresti A, Luongo E.
europepmc +1 more source
Operator means, barycenters, and fixed point equations. [PDF]
Acta Sci MathVirosztek D.
europepmc +1 more source