Classical expansions and their relation to conjugate harmonic functions
Classical expansions and their relation to conjugate harmonic functions
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DOI:
10.1090/s0002-9947-1965-0199636-9
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发表时间:
1965-06
影响因子:
1.3
通讯作者:
B. Muckenhoupt;E. Stein
中科院分区:
文献类型:
--
作者:
B. Muckenhoupt;E. Stein
The common idea which unifies most of the techniques and results obtained here centers about the study of harmonic functions and their conjugates in several variables, and their variants. Ordinary Fourier series and integrals have an intimate connection with analytic functions, and this relation which they enjoy has long provided a fundamental tool in their study. Thus one of our main ob-jectives is the development of an analogous tool for the other expansions in question.The connection that is used between various expansions and generalized har-monic and conjugate harmonic functions seems to be of basic importance. In its formal aspects this connection has its roots in the classical literature. More recently, however, some of the ideas have been taken up in the theory of axially symmetric potential theory (see Weinstein [24]) and in the study of pseudoanalytic functions of Bers [2],[3], and Vekua [20]. We now describe in more detail the background and statements of our results ('). We begin by recalling some of the basic properties of the ultraspherical expansions and Fourier-Bessel transforms. Fix A> 0, and consider the ultraspherical polynomials of degree n, PR (t), defined by the generating relation: