Universal maps on trees
نویسنده
چکیده
A map f : R ! S of continua R and S is called a universal map from R to S if for any map g : R ! S, f(x) = g(x) for some point x 2 R. When R and S are trees, we characterize universal maps by reducing to the case of light minimal universal maps. The characterization uses the notions of combinatorial map and folded subedge of R. MOS Subject Classi cation Primary: 54H25 Secondary: 54F20
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تاریخ انتشار 2000