, Volume 6, Issue 3, pp 235–240 | Cite as

Sphere orders

  • Graham Brightwell
  • Peter Winkler


Ann-sphere order is a finite partially ordered set representable by containment ofn-spheres in Euclidean (n+1)-space. We present a sequence {P i } of ordered sets such that eachP i is ann-sphere order only forn≥i; one consequence is that we are able to determine the dimension of a Euclidean space-time manifold from the finite suborders of its causality order.

AMS subject classifications (1980)

06A10 52A37 

Key words

Order sphere partially ordered set space-time 


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Graham Brightwell
    • 1
  • Peter Winkler
    • 2
  1. 1.London School of Economics and Political ScienceLondonUnited Kingdom
  2. 2.BellcoreMorristownU.S.A.

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