Articles

Notes on the representational possibilities of projective quadrics in four dimensions

Published:
2006-06-01
Authors
View
Keywords
License

Copyright (c) 2006 Sándor Bácsó and Zoltán Szilasi

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How To Cite
Selected Style: APA
Bácsó, S., & Szilasi, Z. (2006). Notes on the representational possibilities of projective quadrics in four dimensions. Teaching Mathematics and Computer Science, 4(1), 167-177. https://doi.org/10.5485/TMCS.2006.0114
Abstract
The paper deals with hyper-quadrics in the real projective 4-space. According to [1] there exist 11 types of hypersurfaces of 2nd order, which can be represented by 'projective normal forms' with respect to a polar simplex as coordinate frame. By interpreting this frame as a Cartesian frame in the (projectively extended) Euclidean 4-space one will receive sort of Euclidean standard types of hyper-quadrics resp., hypersurfaces of 2nd order: the sphere as representative of hyper-ellipsoids, equilateral hyper-hyperboloids, and hyper-cones of revolution. It seems to be worthwhile to visualize the "typical" projective hyper-quadrics by means of descriptive geometry in the (projectively extended) Euclidean 4-space using Maurin's method [4] or the classical (skew) axonometric mapping of that 4-space into an image plane.