Existence and uniqueness conditions for solutions of linear functional equations in the classes of Lebesgue functions antiderivatives on a simple smooth curve
Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika, Tome 13 (2021) no. 4, pp. 13-23

Voir la notice de l'article provenant de la source Math-Net.Ru

The article describes linear functional equations on simple smooth curves with a shift function and fixed points only at the ends of the curve. The case when the shift function has a nonzero derivative satisfying the Hölder condition is considered. The objective of the article is to find the conditions of the existence and uniqueness of such equations solution in the classes of Lebesgue functions antiderivatives with a coefficient and the right-hand part belonging to the same classes. These conditions depend on the values of the equation coefficient at the ends of the curve. It is shown that if the coefficient and the right-hand side of a functional equation belong to the class of Lebesgue functions antiderivatives, then its solution also belongs to this class. The indicators of Hölder and of classes of Lebesgue functions antiderivatives are determined for the solutions. The research method is based on F. Riesz's criterion of a function's belonging to the class of antiderivatives of Lebesgue integrable functions. The possibilities of applying linear functional equations for studying and solving singular integral equations with logarithmic singularities are shown.
Keywords: singular integral equations with a shift, linear functional equations with a single variable, classes of Lebesgue functions antiderivatives.
@article{VYURM_2021_13_4_a1,
     author = {V. L. Dilman and D. A. Komissarova},
     title = {Existence and uniqueness conditions for solutions of linear functional equations in the classes of {Lebesgue} functions antiderivatives on a simple smooth curve},
     journal = {Vestnik \^U\v{z}no-Uralʹskogo gosudarstvennogo universiteta. Seri\^a, Matematika, mehanika, fizika},
     pages = {13--23},
     publisher = {mathdoc},
     volume = {13},
     number = {4},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VYURM_2021_13_4_a1/}
}
TY  - JOUR
AU  - V. L. Dilman
AU  - D. A. Komissarova
TI  - Existence and uniqueness conditions for solutions of linear functional equations in the classes of Lebesgue functions antiderivatives on a simple smooth curve
JO  - Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika
PY  - 2021
SP  - 13
EP  - 23
VL  - 13
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/VYURM_2021_13_4_a1/
LA  - ru
ID  - VYURM_2021_13_4_a1
ER  - 
%0 Journal Article
%A V. L. Dilman
%A D. A. Komissarova
%T Existence and uniqueness conditions for solutions of linear functional equations in the classes of Lebesgue functions antiderivatives on a simple smooth curve
%J Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika
%D 2021
%P 13-23
%V 13
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/item/VYURM_2021_13_4_a1/
%G ru
%F VYURM_2021_13_4_a1
V. L. Dilman; D. A. Komissarova. Existence and uniqueness conditions for solutions of linear functional equations in the classes of Lebesgue functions antiderivatives on a simple smooth curve. Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika, Tome 13 (2021) no. 4, pp. 13-23. http://geodesic.mathdoc.fr/item/VYURM_2021_13_4_a1/