Abstract:
We introduce the notion of spherical jump of a function of several variables at a given point with respect to a homogeneous harmonic polynomial. Here, if the function is integrable over spheres of sufficiently small radius centered at the given point and is continuous at this point, then its spherical jump at this point with respect to any homogeneous harmonic polynomial, distinct from a constant, is zero. Under certain conditions on a function of n variables (n⩾2) at a point where the spherical jump of this function with respect to a homogeneous harmonic polynomial P is distinct from zero, we calculate the first term of the asymptotics of the spherical Bochner–Riesz means of the critical order (n−1)/2 of the series (integral) conjugate to the n-multiple Fourier series (integral) of this function with respect to the Riesz-type kernel generated by the polynomial P. This first term of the asymptotics contains the spherical jump of the function as a multiplicative constant.
Keywords:
spherical jump of a function, harmonic polynomial, Bochner–Riesz mean, multiple Fourier series, Fourier integral, Riesz-type kernel.
Citation:
B. I. Golubov, “Spherical Jump of a Function and the Bochner–Riesz Means of Conjugate Multiple Fourier Series and Fourier Integrals”, Mat. Zametki, 91:4 (2012), 506–514; Math. Notes, 91:4 (2012), 479–486
\Bibitem{Gol12}
\by B.~I.~Golubov
\paper Spherical Jump of a Function and the Bochner--Riesz Means of Conjugate Multiple Fourier Series and Fourier Integrals
\jour Mat. Zametki
\yr 2012
\vol 91
\issue 4
\pages 506--514
\mathnet{http://mi.mathnet.ru/mzm8739}
\crossref{https://doi.org/10.4213/mzm8739}
\mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=3201450}
\elib{https://elibrary.ru/item.asp?id=20731510}
\transl
\jour Math. Notes
\yr 2012
\vol 91
\issue 4
\pages 479--486
\crossref{https://doi.org/10.1134/S0001434612030212}
\isi{https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=Publons&SrcAuth=Publons_CEL&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=000303478900021}
\elib{https://elibrary.ru/item.asp?id=17983871}
\scopus{https://www.scopus.com/record/display.url?origin=inward&eid=2-s2.0-84860358300}
Linking options:
https://www.mathnet.ru/eng/mzm8739
https://doi.org/10.4213/mzm8739
https://www.mathnet.ru/eng/mzm/v91/i4/p506
This publication is cited in the following 10 articles:
A. Yu. Trynin, “O skhodimosti obobschenii sink-approksimatsii na klasse Privalova–Chanturiya”, Sib. zhurn. industr. matem., 24:3 (2021), 122–137
A. Yu. Trynin, “On the Convergence of Generalizations of the Sinc Approximations on the Privalov–Chanturia Class”, J. Appl. Ind. Math., 15:3 (2021), 531
A. Yu. Trynin, E. D. Kireeva, “Printsip lokalizatsii na klasse funktsii, integriruemykh po Rimanu, dlya protsessov Lagranzha–Shturma–Liuvillya”, Izv. Sarat. un-ta. Nov. ser. Ser.: Matematika. Mekhanika. Informatika, 20:1 (2020), 51–63
A. Yu. Trynin, “On the uniform approximation of functions of bounded variation by Lagrange interpolation
polynomials with a matrix L(αn,βn)n of Jacobi nodes”, Izv. Math., 84:6 (2020), 1224–1249
A. Yu. Trynin, “Error Estimate for Uniform Approximation by Lagrange–Sturm–Liouville Processes”, J Math Sci, 247:6 (2020), 939
A. Yu. Trynin, “Uniform convergence of Lagrange–Sturm–Liouville processes on one functional class”, Ufa Math. J., 10:2 (2018), 93–108
A. Yu. Trynin, “Approximation of continuous on a segment functions with the help of linear combinations of sincs”, Russian Math. (Iz. VUZ), 60:3 (2016), 63–71
A. Yu. Trynin, “On necessary and sufficient conditions for convergence of sinc-approximations”, St. Petersburg Math. J., 27:5 (2016), 825–840
A. Yu. Trynin, “On some properties of sinc approximations of continuous functions on the interval”, Ufa Math. J., 7:4 (2015), 111–126