Resonances generated by analytic singularities on the density of states measure for perturbed periodic Schrödinger operators.
Resonances in an abstract analytic scattering theory
Resonant delocalization for random Schrödinger operators on tree graphs
We analyse the spectral phase diagram of Schrödinger operators on regular tree graphs, with the graph adjacency operator and a random potential given by random variables. The main result is a criterion for the emergence of absolutely continuous spectrum due to fluctuation-enabled resonances between distant sites. Using it we prove that for unbounded random potentials spectrum appears at arbitrarily weak disorder in an energy regime which extends beyond the spectrum of. Incorporating...
Resonant problem for a class of bvps on the half-line.
Restriction of an operator to the range of its powers
Let T be a bounded linear operator acting on a Banach space X. For each integer n, define to be the restriction of T to viewed as a map from into . In [1] and [2] we have characterized operators T such that for a given integer n, the operator is a Fredholm or a semi-Fredholm operator. We continue those investigations and we study the cases where belongs to a given regularity in the sense defined by Kordula and Müller in[10]. We also consider the regularity of operators with topological...
Results for twin singular nonlinear problems with damping term.
Results in L..(...) for the Schrödinger equation with a time-dependent potential.
Results of nonexistence of solutions for some nonlinear evolution problems
In the present paper, we prove nonexistence results for the following nonlinear evolution equation, see works of T. Cazenave and A. Haraux (1990) and S. Zheng (2004), posed in where is -fractional power of Our method of proof is based on suitable choices of the test functions in the weak formulation of the sought solutions. Then, we extend this result to the case of a system of the same type.
Results on common fixed points.
Results on controlling the residuals of perturbed Newton-like methods on Banach spaces with a convergence structure.
Results on Non-resonant Oscillations for some Nonlinear Vector Fourth Order Differential Systems
This paper presents vector versions of some existence results recently published for certain fourth order differential systems based on generalisations drawn from possibilities arising from the underlying auxiliary equation. The results obtained also extend some known works involving third order differential systems to the corresponding fourth order.
Results on the existence and convergence of best proximity points.
Retractions onto the Space of Continuous Divergence-free Vector Fields
We prove that there does not exist a uniformly continuous retraction from the space of continuous vector fields onto the subspace of vector fields whose divergence vanishes in the distributional sense. We then generalise this result using the concept of -charges, introduced by De Pauw, Moonens, and Pfeffer: on any subset satisfying a mild geometric condition, there is no uniformly continuous representation operator for -charges in .
Retracts, fixed point index and differential equations.
Some problems in differential equations evolve towards Topology from an analytical origin. Two such problems will be discussed: the existence of solutions asymptotic to the equilibrium and the stability of closed orbits of Hamiltonian systems. The theory of retracts and the fixed point index have become useful tools in the study of these questions.
Reverse inequalities on chaotically geometric mean via Specht ratio. II.
Reverse of the grand Furuta inequality and its applications.
Reverse order law for the Moore-Penrose inverse in -algebras.
Reversibility for diffusions via quasi-invarience
Revisiting Cauty's proof of the Schauder conjecture.
Revisiting the construction of gap functions for variational inequalities and equilibrium problems via conjugate duality
Based on conjugate duality we construct several gap functions for general variational inequalities and equilibrium problems, in the formulation of which a so-called perturbation function is used. These functions are written with the help of the Fenchel-Moreau conjugate of the functions involved. In case we are working in the convex setting and a regularity condition is fulfilled, these functions become gap functions. The techniques used are the ones considered in [Altangerel L., Boţ R.I., Wanka...