1 Contiguity and Contiguity Topology Defintion 1.1 Let X be a non-void set.A contiguity for X is a non-void family U of subsets of X×X such that (a) each member of U contains the diagonal △; (b) if u∈U and u(?)...1 Contiguity and Contiguity Topology Defintion 1.1 Let X be a non-void set.A contiguity for X is a non-void family U of subsets of X×X such that (a) each member of U contains the diagonal △; (b) if u∈U and u(?)v(?)X×X, then v∈U;and (c) if u and v are members of U, then u ∩v∈U. We also call pair (X, U) is a contiguous space. (where U is a contiguity for X).展开更多
文摘1 Contiguity and Contiguity Topology Defintion 1.1 Let X be a non-void set.A contiguity for X is a non-void family U of subsets of X×X such that (a) each member of U contains the diagonal △; (b) if u∈U and u(?)v(?)X×X, then v∈U;and (c) if u and v are members of U, then u ∩v∈U. We also call pair (X, U) is a contiguous space. (where U is a contiguity for X).