A note on the homotopy type of posets
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P. Sankaran; K. Varadarajan
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Article
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1994
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Elsevier Science
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English
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For any poset P let J(P) denote the complete lattice of order ideals in P. J(P) is a contravariant functor in P. Any order-reversing map f: P-+Q can be regarded as an isotone (= order-preserving) map of either P\* into Q or P into Q\*. The induced map of J(Q) to J(P\*) (resp. J(Q\*) into J(P)) will