A Class of Homomorphisms of Pre-Hjelmslev Groups
Canadian journal of mathematics, Tome 36 (1984) no. 3, pp. 470-494

Voir la notice de l'article provenant de la source Cambridge University Press

E. Salow [8] introduced the concept of pre-Hjelmslev groups, a generalization of F. Bachmann's Hjelmslev groups [1] which leads to a more natural theory of homomorphisms and permits a simpler construction of algebraic models. Basically, both types of groups are the groups of motions of a metric plane, the so-called group plane. In such a plane there is a unique perpendicular through any point to any line and the product of three collinear points (three copunctal lines) is a point (a line). Our first section contains the precise definitions and some basic facts.The homomorphic image of a pre-Hjelmslev group can be more complicated than the pre-image. For instance, there may always be a unique line through two distinct points of the pre-image but not of the image. We study regular homomorphisms of pre-Hjelmslev groups, i.e., homomorphisms with the following property: If two lines intersect at exactly one point, their images will also have precisely one point in common.
Knüppel, Frieder. A Class of Homomorphisms of Pre-Hjelmslev Groups. Canadian journal of mathematics, Tome 36 (1984) no. 3, pp. 470-494. doi: 10.4153/CJM-1984-029-4
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[1] 1. Bachmann, F., Aufbau der Geometrie aus clem Spiege lungs be griff, Second supplemented edition (Springer, 1973). Google Scholar | DOI

[2] 2. Bachmann, F., Hjelmslev-Gruppen. Arbeitsgemeinschaft über geometrische Fragen, Universität Kiel, second print (1976). Google Scholar

[3] 3. Klingenberg, W., Euklidische Ebenen mit Nachbar element en, Math. Z. 61 (1954), 1–25. Google Scholar

[4] 4. Knüppel, F. and Kunze, M., Neighbor relation and neighbor homomorphism of Hjelmslev groups, Can. J. Math. 31 (1979), 680–699. Google Scholar

[5] 5. Knüppel, F. and Kunze, M., Regulare Hjelmslev-Homomorphismen, Geom. Ded. 11 (1981), 195–225. Google Scholar

[6] 6. Knüppel, F., Äquiforme Ebenen über kommutativen Ringen und singuläre Prä-Hjelmslev-gruppen, Abh. math. Sem. Univ. Hamburg 54 (1983), 229–257. Google Scholar

[7] 7. Knüppel, F., The set of fixed points of a rotation in a pre-Hjelmslev group, to appear. Google Scholar

[8] 8. Salow, E., Singuläre Hjelmslev-Gruppen, Geom. Ded. 1 (1973), 447–467. Google Scholar

[9] 9. Salow, E., Fixpunktmenge von Drehungen in Hjelmslev-Gruppen, Abh. math. Sem. Univ. Hamburgh (1974), 37–73. Google Scholar

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