Results 21 to 30 of about 736 (56)
On positivity and roots in operator algebras [PDF]
, 2014 In earlier papers the second author and Charles Read have introduced and studied a new notion of positivity for operator algebras, with an eye to extending certain C*-algebraic results and theories to more general algebras.
Bearden, Clifford A. +2 more
core +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
Linear Fractional PDE, Uniqueness of Global Solutions [PDF]
, 2005 Mathematics Subject Classification: 26A33, 47A60, 30C15.In this paper we treat the question of existence and uniqueness of solutions of linear fractional partial differential equations.
Kempfle, Siegmar +2 more
core
The sectorial projection defined from logarithms
, 2011 For a classical elliptic pseudodifferential operator P of order m>0 on a closed manifold X, such that the eigenvalues of the principal symbol p_m(x,\xi) have arguments in \,]\theta,\phi [\, and \,]\phi, \theta +2\pi ...
Grubb, Gerd
core +1 more source
Nash type inequalities for fractional powers of non-negative self-adjoint operators [PDF]
Transaction of the American Mathematical Society. 359, 7 (2007)
3085-3097, 2004 Assuming that a Nash type inequality is satisfied by a non-negative self-adjoint operator $A$, we prove a Nash type inequality for the fractional powers $A^{\alpha}$ of $A$. Under some assumptions, we give ultracontractivity bounds for the semigroup $(T_{t,{\alpha}})$ generated by $-A^{\alpha}$.
arxiv +1 more source
Asymptotic parabolicity for strongly damped wave equations
, 2013 For $S$ a positive selfadjoint operator on a Hilbert space, \[ \frac{d^2u}{dt}(t) + 2 F(S)\frac{du}{dt}(t) + S^2u(t)=0 \] describes a class of wave equations with strong friction or damping if $F$ is a positive Borel function.
Fragnelli, Genni +3 more
core +1 more source
Further refinements of the Cauchy-Schwarz inequality for matrices [PDF]
, 2014 Let $A, B$ and $X$ be $n\times n$ matrices such that $A, B$ are positive semidefinite. We present some refinements of the matrix Cauchy-Schwarz inequality by using some integration techniques and various refinements of the Hermite--Hadamard inequality ...
Bakherad, Mojtaba
core
Integral equalities for functions of unbounded spectral operators in Banach spaces [PDF]
Dissertationes Mathematicae, 464 (2009), 2008 We investigate a limiting procedure for extending local integral operator equalities to the global ones and to applying it to obtaining generalizations of the Newton-Leibnitz formula for operator-valued maps for a wide class of unbounded operators.
arxiv +1 more source
, 2002 We establish what we consider to be the definitive versions of Jensen's operator inequality and Jensen's trace inequality for functions defined on an interval.
Hansen, Frank, Pedersen, Gert K.
core +1 more source
Some operator Bellman type inequalities
, 2015 In this paper, we employ the Mond--Pe\v{c}ari\'c method to establish some reverses of the operator Bellman inequality under certain conditions. In particular, we show \begin{equation*} \delta I_{\mathscr K}+\sum_{j=1}^n\omega_j\Phi_j\left((I_{\mathscr H}-
Bakherad, Mojtaba, Morassaei, Ali
core +1 more source