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Introduction to Groups and Geometries
David W. Lyons
Contents
Index
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Contents
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Front Matter
Colophon
Preface
About the author
1
Preliminaries
Complex Numbers
Quaternions
Stereographic projection
Equivalence Relations
2
Groups
Examples of groups
Definition of a group
Subgroups and cosets
Group homomorphisms
Group actions
Additional exercises
3
Geometries
Geometries and models
Möbius geometry
Hyperbolic geometry
Elliptic geometry
Projective geometry
Additional exercises
Back Matter
Further topics
References
Index
Notation
Authored in PreTeXt
Introduction to Groups and Geometries
David W. Lyons
Department of Mathematical Sciences
Lebanon Valley College
Annville, PA, USA
lyons@lvc.edu
January 2021 Edition, revised: March 2, 2021
Comments, discussion, error reports, and so on, are welcome.
Colophon
Preface
About the author