Abstract
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.
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Communicated by I. Rival
Research supported by ONR grant N00014 85-K-0769.
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Brightwell, G., Winkler, P. Sphere orders. Order 6, 235–240 (1989). https://doi.org/10.1007/BF00563524
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DOI: https://doi.org/10.1007/BF00563524