IDEAS home Printed from https://ideas.repec.org/h/spr/sprchp/978-3-658-38640-5_3.html
   My bibliography  Save this book chapter

Incidence: Projective Geometry

In: Geometry - Intuition and Concepts

Author

Listed:
  • Jost-Hinrich Eschenburg

    (Universität Augsburg, Institut für Mathematik)

Abstract

Projective geometry is the proper domain for the notion of incidence for straight lines and points; it knows no other basic notions. The basic ideas were developed 600 years ago with the discovery of central perspective. The artists pioneered the mathematicians. Just as in a perspective view parallel lines appear to have a point of intersection on the horizon, so parallelism is interpreted as “intersecting at infinity”. For this, geometry must be extended by “points at infinity”. These arise quite easily by embedding into linear algebra: This extended (“projective”) geometry, however, no longer takes place on a vector space as affine geometry does, but on the set of its one-dimensional linear subspaces. The structure-preserving transformations (“collineations”) are then simply the (semi-)linear isomorphisms of the vector space. Now for the first time in this book interesting geometric theorems are discussed, the theorems of Desargues, Brianchon and Pascal. We will get to know conic sections and quadrics, and at the end an important numerical quantity which is invariant under projective transformations: the cross-ratio.

Suggested Citation

  • Jost-Hinrich Eschenburg, 2022. "Incidence: Projective Geometry," Springer Books, in: Geometry - Intuition and Concepts, chapter 3, pages 21-55, Springer.
  • Handle: RePEc:spr:sprchp:978-3-658-38640-5_3
    DOI: 10.1007/978-3-658-38640-5_3
    as

    Download full text from publisher

    To our knowledge, this item is not available for download. To find whether it is available, there are three options:
    1. Check below whether another version of this item is available online.
    2. Check on the provider's web page whether it is in fact available.
    3. Perform a
    for a similarly titled item that would be available.

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:spr:sprchp:978-3-658-38640-5_3. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Sonal Shukla or Springer Nature Abstracting and Indexing (email available below). General contact details of provider: http://www.springer.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.