Möbius transformation

Etymology
Named for German mathematician and theoretical astronomer (1790–1868).

Noun

 * 1)  A transformation of the extended complex plane that is a rational function of the form f(z) = (az + b) / (cz + d), where a, b, c, d are complex numbers such that ad &minus; bc ≠ 0; an automorphism of the complex projective line.
 * 2) * 2008, J. Vernon Armitage, John Parker, Jørgensen's inequality for Non-Archimedean Metric Spaces, Mikhail Kapranov, Sergii Kolyada, Yu. I. Manin, Pieter Moree, Leonid Potyagailo (editors), Geometry and Dynamics of Groups and Spaces: In Memory of Alexander Reznikov, page 97,
 * Jørgensen's inequality gives a necessary condition for a non-elementary group of Möbius transformations to be discrete.
 * 1) * 2012, Martin Delacourt, Petr Kůrka, Finite State Transducers of Modular Möbius Number Systems, Branislav Rovan, Vladimiro Sassone, Peter Widmayer (editors), Mathematical Foundations of Computer Science 2012, 37th International Symposium, MFCS 2012, Proceedings, Springer, LNCS 7464, page 323,
 * Modular Möbius number systems consist of Möbius transformations with integer coefficients and unit determinant.

Translations

 * Dutch: Möbius-transformatie
 * French: transformation de Möbius
 * German: Möbiustransformation
 * Italian: trasformazione di Möbius
 * Portuguese: transformação de Möbius
 * Spanish: transformación de Möbius