Proof of an Intersection Theorem via Graph Homomorphisms

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Proof of an Intersection Theorem via Graph Homomorphisms

Let 0 ≤ p ≤ 1/2 and let {0, 1} be endowed with the product measure μp defined by μp(x) = p |x|(1 − p)n−|x|, where |x| = ∑ xi. Let I ⊆ {0, 1} n be an intersecting family, i.e. for every x, y ∈ I there exists a coordinate 1 ≤ i ≤ n such that xi = yi = 1. Then μp(I) ≤ p. Our proof uses measure preserving homomorphisms between graphs. One of the fundamental questions first studied in extremal graph...

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ژورنال

عنوان ژورنال: The Electronic Journal of Combinatorics

سال: 2006

ISSN: 1077-8926

DOI: 10.37236/1144