Mellin transform

The integral transform

The substitution reduces it to the Laplace transform. The Mellin transform is used for solving a specific class of planar problems for harmonic functions in a sectorial domain, of problems in elasticity theory, etc.

The inversion theorem. Suppose that and that the function has bounded variation in a neighbourhood of the point . Then

The representation theorem. Suppose that the function is summable with respect to on and has bounded variation in a neighbourhood of the point . Then

where

References

[1]	H. Mellin, "Ueber die fundamentelle Wichtigkeit des Satzes von Cauchy für die Theorie der Gamma- und hypergeometrischen Funktionen" Acta Soc. Sci. Fennica , 21 : 1 (1896) pp. 1–115
[2]	H. Mellin, "Ueber den Zusammenhang zwischen linearen Differential- und Differenzengleichungen" Acta Math. , 25 (1902) pp. 139–164
[3]	E.C. Titchmarsh, "Introduction to the theory of Fourier integrals" , Oxford Univ. Press (1948)
[4]	V.A. Ditkin, A.P. Prudnikov, "Transformations intégrales et calcul opérationnel" , MIR (1978) (Translated from Russian)

Comments

If denotes the Mellin transform of , then the Parseval equality takes the form:

if .

The Mellin transform also serves to link Dirichlet series with automorphic functions (cf. Automorphic function); in particular, the inversion formula plays a role in the proof of a functional equation for Dirichlet series similar to that for the Riemann zeta-function. Cf. [a1]–[a5].

References

[a1]	E. Hecke, "Ueber die Bestimmung Dirichletscher Reihen durch ihre Funktionalgleichung" Math. Ann. , 112 (1936) pp. 664–699
[a2]	A. Weil, "Ueber die Bestimmung Dirichletscher Reihen durch ihre Funktionalgleichung" Math. Ann. , 168 (1967) pp. 149–156
[a3]	A. Weil, "Zeta functions and Mellin transforms" , Algebraic geometry (Bombay Coll., 1968) , Oxford Univ. Press & Tata Inst. (1968) pp. 409–426
[a4]	A. Ogg, "Modular forms and Dirichlet series" , Benjamin (1969)
[a5]	G. Shimura, "Introduction to the arithmetic theory of automorphic functions" , Princeton Univ. Press & Iwanami-Shoten (1971) pp. §3.6, pp 89–94