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A remark on the local Lipschitz continuity of vector hysteresis operators

Pavel Krejčí (2001)

Applications of Mathematics

It is known that the vector stop operator with a convex closed characteristic Z of class C 1 is locally Lipschitz continuous in the space of absolutely continuous functions if the unit outward normal mapping n is Lipschitz continuous on the boundary Z of Z . We prove that in the regular case, this condition is also necessary.

A representation of the coalgebra of derivations for smooth spaces

Fischer, Gerald (1999)

Proceedings of the 18th Winter School "Geometry and Physics"

Let K be a field. The generalized Leibniz rule for higher derivations suggests the definition of a coalgebra 𝒟 K k for any positive integer k . This is spanned over K by d 0 , ... , d k , and has comultiplication Δ and counit ε defined by Δ ( d i ) = j = 0 i d j d i - j and ε ( d i ) = δ 0 , i (Kronecker’s delta) for any i . This note presents a representation of the coalgebra 𝒟 K k by using smooth spaces and a procedure of microlocalization. The author gives an interpretation of this result following the principles of the quantum theory of geometric spaces.

A Riemann-Roch-Hirzebruch formula for traces of differential operators

Markus Engeli, Giovanni Felder (2008)

Annales scientifiques de l'École Normale Supérieure

Let D be a holomorphic differential operator acting on sections of a holomorphic vector bundle on an n -dimensional compact complex manifold. We prove a formula, conjectured by Feigin and Shoikhet, giving the Lefschetz number of D as the integral over the manifold of a differential form. The class of this differential form is obtained via formal differential geometry from the canonical generator of the Hochschild cohomology H H 2 n ( 𝒟 n , 𝒟 n * ) of the algebra of differential operators on a formal neighbourhood of a...

A short note on f -biharmonic hypersurfaces

Selcen Y. Perktaş, Bilal E. Acet, Adara M. Blaga (2020)

Commentationes Mathematicae Universitatis Carolinae

In the present paper we give some properties of f -biharmonic hypersurfaces in real space forms. By using the f -biharmonic equation for a hypersurface of a Riemannian manifold, we characterize the f -biharmonicity of constant mean curvature and totally umbilical hypersurfaces in a Riemannian manifold and, in particular, in a real space form. As an example, we consider f -biharmonic vertical cylinders in S 2 × .

A special type of triangulations in numerical nonlinear analysis.

J. M. Soriano (1990)

Collectanea Mathematica

To calculate the zeros of a map f : Rn → Rn we consider the class of triangulations of Rn so that a certain point belongs to a simplex of fixed diameter and dimension. In this paper two types of this new class of triangulations are constructed and shown to be useful to calculate zeros of piecewise linear approximations of f.

A spectral estimate for the Dirac operator on Riemannian flows

Nicolas Ginoux, Georges Habib (2010)

Open Mathematics

We give a new upper bound for the smallest eigenvalues of the Dirac operator on a Riemannian flow carrying transversal Killing spinors. We derive an estimate on both Sasakian and 3-dimensional manifolds, and partially classify those satisfying the limiting case. Finally, we compare our estimate with a lower bound in terms of a natural tensor depending on the eigenspinor.

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