A bornological approach to rotundity and smoothness applied to approximation.
A chart preserving the normal vector and extensions of normal derivatives in weighted function spaces
Given a domain of class , , we construct a chart that maps normals to the boundary of the half space to normals to the boundary of in the sense that and that still is of class . As an application we prove the existence of a continuous extension operator for all normal derivatives of order 0 to on domains of class . The construction of this operator is performed in weighted function spaces where the weight function is taken from the class of Muckenhoupt weights.
A class of generalized best approximation problems in locally convex linear topological spaces.
A generalization of Dubovitskij-Miliutin theorem
A generalized dual maximizer for the Monge–Kantorovich transport problem
The dual attainment of the Monge–Kantorovich transport problem is analyzed in a general setting. The spaces X,Y are assumed to be polish and equipped with Borel probability measures μ and ν. The transport cost function c : X × Y → [0,∞] is assumed to be Borel measurable. We show that a dual optimizer always exists, provided we interpret it as a projective limit of certain finitely additive measures. Our methods are functional analytic and rely on Fenchel’s perturbation technique.
A generalized dual maximizer for the Monge–Kantorovich transport problem∗
The dual attainment of the Monge–Kantorovich transport problem is analyzed in a general setting. The spaces X,Y are assumed to be polish and equipped with Borel probability measures μ and ν. The transport cost function c : X × Y → [0,∞] is assumed to be Borel measurable. We show that a dual optimizer always exists, provided we interpret it as a projective limit of certain finitely additive measures. Our methods are functional analytic...
A generalized Fannes' inequality.
A "hidden" characterization of approximatively polyhedral convex sets in Banach spaces
A closed convex subset C of a Banach space X is called approximatively polyhedral if for each ε > 0 there is a polyhedral (= intersection of finitely many closed half-spaces) convex set P ⊂ X at Hausdorff distance < ε from C. We characterize approximatively polyhedral convex sets in Banach spaces and apply the characterization to show that a connected component of the space of closed convex subsets of X endowed with the Hausdorff metric is separable if and only if contains a polyhedral convex...
A low temperature expansion for the pseudoscalar Yukawa model of quantum fields in two space-time dimensions
A model of atomic radiation
A Modeling Framework For Immune-related Diseases
About twenty five years ago the first discrete mathematical model of the immune system was proposed. It was very simple and stylized. Later, many other computational models have been proposed each one adding a certain level of sophistication and detail to the description of the system. One of these, the Celada-Seiden model published back in 1992, was already mature at its birth, setting apart from the topic-specific nature of the other models. This...
A natural derivative on [0, n] and a binomial Poincaré inequality
We consider probability measures supported on a finite discrete interval [0, n]. We introduce a new finite difference operator ∇n, defined as a linear combination of left and right finite differences. We show that this operator ∇n plays a key role in a new Poincaré (spectral gap) inequality with respect to binomial weights, with the orthogonal Krawtchouk polynomials acting as eigenfunctions of the relevant operator. We briefly discuss the relationship of this operator to the problem of optimal transport...
A new algorithm for approximating the least concave majorant
The least concave majorant, , of a continuous function on a closed interval, , is defined by We present an algorithm, in the spirit of the Jarvis March, to approximate the least concave majorant of a differentiable piecewise polynomial function of degree at most three on . Given any function , it can be well-approximated on by a clamped cubic spline . We show that is then a good approximation to . We give two examples, one to illustrate, the other to apply our algorithm.
A note on Banach spaces and sub differentials of convex functions
A note on extremality and completeness in financial markets with infinitely many risky assets
A note on singular points of convex functions in Banach spaces
A note on the application of integrals involving cyclic products of kernels.
In statistics of stochastic processes and random fields, a moment function or a cumulant of an estimate of either the correlation function or the spectral function can often contain an integral involving a cyclic product of kernels. We define and study this class of integrals and prove a Young-Hölder inequality. This inequality further enables us to study asymptotics of the above mentioned integrals in the situation where the kernels depend on a parameter. An application to the problem of estimation...
A proximal point method for nonsmooth convex optimization problems in Banach spaces.
A quantum particle in a quadrupole radio-frequency trap
A representation theorem for time-scale functionals