{ "id": "math/9904047", "version": "v5", "published": "1999-04-12T02:15:20.000Z", "updated": "1999-05-05T02:37:46.000Z", "title": "Discrete versions of the Beckman-Quarles theorem", "authors": [ "Apoloniusz Tyszka" ], "comment": "LaTeX209, 14 pages, textonly.tex, text&gif.ps, to appear in Aeq. Math", "journal": "Aequationes Mathematicae 59 (2000), pp.124-133", "categories": [ "math.MG" ], "abstract": "TO APPEAR IN AEQUATIONES MATHEMATICAE - WITHOUT THEOREM 2. THEOREM 2 IS CORRECTLY PROVED IN PREVIOUS VERSIONS 1 AND 2. AUTHOR'S VERSION 3 (WITH A NEW FIGURE 6A) IS UNNECESSARY. Let F \\subseteq R denote the field of numbers which are constructible by means of ruler and compass. We prove that: (1) if x,y \\in R^n (n>1) and |x-y| is an algebraic number then there exists a finite set S(x,y) \\subseteq R^n containing x and y such that each map from S(x,y) to R^n preserving all unit distances preserves the distance between x and y; if x,y \\in F^n then we can choose S(x,y) \\subseteq F^n, (2) only algebraic distances |x-y| have the property from item (1), (3) if X1,X2,...,Xm \\in R^n (n>1) lie on some affine hyperplane then there exists a finite set L(X1,X2,...,Xm) \\subseteq R^n containing X1,X2,...,Xm such that each map from L(X1,X2,...,Xm) to R^n preserving all unit distances preserves the property that X1,X2,...,Xm lie on some affine hyperplane, (4) if J,K,L,M \\in R^n (n>1) and |JK|=|LM| (|JK|<|LM|) then there exists a finite set C(J,K,L,M) \\subseteq R^n containing J,K,L,M such that any map f:C(J,K,L,M) \\to R^n that preserves unit distance satisfies |f(J)f(K)|=|f(L)f(M)| (|f(J)f(K)|<|f(L)f(M)|).", "revisions": [ { "version": "v5", "updated": "1999-05-05T02:37:46.000Z" } ], "analyses": { "subjects": [ "51M05", "05C12" ], "keywords": [ "beckman-quarles theorem", "discrete versions", "unit distances preserves", "finite set", "affine hyperplane" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1999math......4047T" } } }