Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

This modern translation of Sophus Lie's and Friedrich Engel's "Theorie der Transformationsgruppen I" will allow readers to discover the striking conceptual clarity and remarkably systematic organizational thought of the original German text. Volume I presents a comprehensive introduction to the theory and is mainly directed towards the generalization of ideas drawn from the study of examples. The major part of the present volume offers an extremely clear translation of the lucid original. The first four chapters provide not only a translation, but also a contemporary approach, which will help present day readers to familiarize themselves with the concepts at the heart of the subject. The editor's main objective was to encourage a renewed interest in the detailed classification of Lie algebras in dimensions 1, 2 and 3, and to offer access to Sophus Lie's monumental Galois theory of continuous transformation groups, established at the end of the 19th Century. Lie groups are widespread in mathematics, playing a role in representation theory, algebraic geometry, Galois theory, the theory of partial differential equations and also in physics, for example in general relativity. This volume is of interest to researchers in Lie theory and exterior differential systems and also to historians of mathematics. The prerequisites are a basic knowledge of differential calculus, ordinary differential equations and differential geometry.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

This modern translation of Sophus Lie's and Friedrich Engel's “Theorie der Transformationsgruppen I� will allow readers to discover the striking conceptual clarity and remarkably systematic organizational thought of the original German text. Volume I presents a comprehensive introduction to the theory and is mainly directed towards the generalization of ideas drawn from the study of examples. The major part of the present volume offers an extremely clear translation of the lucid original. The first four chapters provide not only a translation, but also a contemporary approach, which will help present day readers to familiarize themselves with the concepts at the heart of the subject. The editor's main objective was to encourage a renewed interest in the detailed classification of Lie algebras in dimensions 1, 2 and 3, and to offer access to Sophus Lie's monumental Galois theory of continuous transformation groups, established at the end of the 19th Century. Lie groups are widespread in mathematics, playing a role in representation theory, algebraic geometry, Galois theory, the theory of partial differential equations and also in physics, for example in general relativity. This volume is of interest to researchers in Lie theory and exterior differential systems and also to historians of mathematics. The prerequisites are a basic knowledge of differential calculus, ordinary differential equations and differential geometry.

In diesem Monat feiern wir den 150. Geburtstag von SOPHUS LIE, einem der groessten Mathematiker des vorigen Jahrhunderts. Es ist daher sehr zu begrussen, dass der Teubner Verlag, einer langen Traditionslinie bei der Veroeffentlichung von LIES Werken folgend, in seine Reihe "TEUBNER-ARCHIV zur Mathematik" Arbeiten von SOPHUS LIE und seinen Zeitgenossen EDuARD STUDY und FRIEDRICH ENGEL aufgenommen hat. Ausgewahlt wurden Beitrage zur Theorie der Differentialinvarianten. Zum einen ist dies ein Gebiet, auf dem alle drei tatig gewesen sind und das als Ausgangspunkt grosser Liescher Ideen zur Anwendung gruppentheoretischer Methoden in der Analysis betrachtet werden kann, obwohl es nur einen Ausschnitt aus LIES Schaffen darstellt. Zum anderen vermitteln die hier vorgestellten Arbeiten durch ihren kritischen Stil und durch den Streit um unterschied liche mathematische Auffassungen interessante Einblicke in das mathematische Geschehen jener Zeit. Neben der Wurdigung dieser drei namhaften Mathematiker stellt der vorliegende Band den Ursprung der Lieschen Theorie, ihre weitere Entwicklung und spatere Auspragung dar. Wir danken dem Teubner-Verlag und insbesondere Herrn J. WEISS fur das freundliche Entgegenkommen und die gute Zusammenarbeit. Greifswald und Leipzig, Dezember 1992 GUENTER CZICHOWSKI BERND FRITZSCHE SOPHUS LIE OElgemalde von ERIK THEODOR WERENSKIOLD aus dem Jahre 1902; im Besitz der Universitat Oslo (Katalognummer 818) Inhalt S. Lie: UEber Gruppen von Transformationen, 1874. (Gesammelte Abhandlungen, Bd. 5 (1924),1-8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 S. Lie: UEber Differentialinvarianten, 1884. (Gesammelte Abhandlungen, Bd. 6 (1927), 95-l38) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 . . . . . . . S. Lie: UEber die Gruppe der Bewegungen und ihre Differentialinvarianten, 1893. (Gesammelte Abhandlungen, Bd. 6 (1927), 376-383) . . . . . . . . . . . . . . .

Das Halten einer Antrittsvorlesung gehArte zu den bewAhrten Traditionen der deutschen UniversitAten. Diese Reden spiegelten in der Regel die Ansichten des Neuberufenen zu allgemeinen Fragen seiner Wissenschaft wider, nicht selten auch programmatische Vorstellungen A1/4ber das zukA1/4nftige Wirken. Sie waren so gehalten, daA sie einem breiten Publikum verstAndlich blieben. Die vorliegende Sammlung Leipziger mathematischer Antrittsvorlesungen der Jahre 1869 bis 1922 enthAlt fotomechanische Nachdrucke der entsprechenden Reden von Carl Neumann, Felix Klein, Sophus Lie, Friedrich Engel, Felix Hausdorff, Heinrich Liebmann, Wilhelm Blaschke und Leon Lichtenstein. Das Buch wird ergAnzt durch kurze Biographien dieser Gelehrten sowie durch einige aufschluAreiche, teilweise noch unverAffentlichte Archivalien.