Generated by GPT-5-mini| Hankel transform | |
|---|---|
| Name | Hankel transform |
| Inventor | Hermann Hankel |
| Introduced | 19th century |
| Related | Bessel function, Fourier transform, Laplace transform |
Hankel transform
The Hankel transform is an integral transform involving Bessel functions introduced in the 19th century by Hermann Hankel. It arises in problems with radial symmetry in Germany, in work connected to the Bessel equation and developments contemporaneous with contributors such as Bernhard Riemann, Carl Gustav Jacobi, and George Green. The transform connects to techniques used by practitioners at institutions like the University of Göttingen and the Polytechnic University of Milan and has been applied in contexts ranging from the Royal Society-published studies to modern computational projects at organizations such as NASA and MIT.
The Hankel transform of order ν is defined by an integral pairing with the Bessel function of the first kind J_ν, a special function studied by Friedrich Bessel and expanded in texts by Oliver Heaviside and Lord Kelvin. In classical treatments appearing in works from the Paris Academy of Sciences and lectures at the École Polytechnique, the transform maps radial functions on [0,∞) to radial spectra using kernels tied to the Bessel functions studied by François Arago-era mathematicians. Formal definitions appear in compendia by authors associated with the Cambridge University Press and the American Mathematical Society.
Key properties mirror those of other integral transforms developed in traditions tied to figures like Joseph Fourier and Pierre-Simon Laplace. Properties include linearity, scaling relations, and an inversion formula relying on orthogonality properties first exploited in studies at the Royal Institution and by analysts affiliated with the Königsberg University. Parseval–Plancherel type identities appear in expositions by scholars at the Institute for Advanced Study and in treatises used in curricula at Princeton University. Convolution theorems for the transform parallel results appearing in the works of Siméon Denis Poisson and later expositions distributed by Springer.
Connections to the Fourier transform and the Laplace transform are historically traced through correspondences among analysts at the Bourbaki gatherings and seminars influenced by the Institut Henri Poincaré. Radial Fourier transforms in dimensions studied by researchers at the University of Cambridge reduce to Hankel transforms; similar reductions appear in treatises by mathematicians from the University of Oxford and in applied analyses at the Max Planck Society. Links to the Mellin transform and to integral representations encountered in monographs associated with the Society for Industrial and Applied Mathematics illustrate how the transform interfaces with frameworks used by engineers at Bell Labs and scientists at the Lawrence Livermore National Laboratory.
Numerical evaluation methods evolved alongside computational projects at institutions such as IBM and laboratories like Los Alamos National Laboratory. Discrete analogues and fast algorithms draw on methods developed in software by groups at Argonne National Laboratory and libraries originating from research at Courant Institute of Mathematical Sciences. Techniques include quadrature schemes influenced by guidelines from the National Institute of Standards and Technology and fast Hankel transform algorithms inspired by fast Fourier transform implementations at Bell Labs Research and by numerical analysts associated with the University of California, Berkeley.
Applications span wave propagation problems studied at the Jet Propulsion Laboratory, imaging modalities advanced at the Mayo Clinic and the Johns Hopkins Hospital, and scattering theory developed in collaborations involving the European Organization for Nuclear Research and the California Institute of Technology. In geophysics, seismic inversion practitioners at the United States Geological Survey employ Hankel-based methods; in optics, investigations at the Max Planck Institute for the Science of Light and industrial research at Siemens have used related transforms. Remote sensing groups at NOAA and antenna designers at Raytheon use radial spectral tools that invoke Hankel transforms, while mathematical models in plasma physics draw on analyses from the Princeton Plasma Physics Laboratory.
Standard pairs are tabulated in manuals used in courses at Harvard University and in handbooks produced by CRC Press. Typical examples include transforms of power-law functions, exponential decays, and Gaussian profiles, commonly encountered in lectures at the University of Chicago and seminar notes distributed by the Mersenne Research community. Tables presenting transforms and inverse pairs appear in reference works associated with the Wiley publishing program and in technical reports from Stanford University.