Discrete groups of affine isometries
Given a finite set S of isometries of an affine Euclidean space. We ask when the group Gamma generated by S is discrete. This includes as a special case the question when the group generated by a finite set of rotations is finite. This latter question is answered in an appendix. In the main part of the paper the general case is reduced to this special case. The result is phrased as a series of tests: Gamma is discrete iff S passes all the tests. The testing procedure is algorithmic.
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321-349
321-349
HELDERMANN VERLAG