Isotopic invariants of natural planar ternary rings
In the paper the invariant (geometrical) character of some properties of natural planar ternary rings is shown by using isotopic transformations.
In the paper the invariant (geometrical) character of some properties of natural planar ternary rings is shown by using isotopic transformations.
Properties of -ary groups connected with the affine geometry are considered. Some conditions for an -ary -group to be derived from a binary group are given. Necessary and sufficient conditions for an -ary group -derived from an additive group of a field to be an -group are obtained. The existence of non-commutative -ary -groups which are not derived from any group of arity for every , is proved.
Bz the quadrileteral condition in a given net there is meant the following implication: If are arbitrary points, no three of them lie on the same line, with coll (collinearity) for any five from six couples then there follows the collinearity coll for the remaining couple . In the article there is proved the every net satisfying the preceding configuration condition is necessarity the Ostrom net (i.e., the net over a field). Conversely, every Ostrom net satisfies the above configuration...
In an absolute space with congruence there are line reflections and point reflections. With the help of point reflections one can define in a natural way an addition + of points which is only associative if the product of three point reflection is a point reflection again. In general, for example for the case that is a linear space with hyperbolic incidence structure, the addition is not associative. is a K-loop or a Bruck loop.