A norm for the cohomology of 2-complexes
نویسنده
چکیده
We introduce a norm on the real 1-cohomology of finite 2complexes determined by the Euler characteristics of graphs on these complexes. We also introduce twisted Alexander-Fox polynomials of groups and show that they give rise to norms on the real 1-cohomology of groups. Our main theorem states that for a finite 2-complex X , the norm on H(X ;R) determined by graphs on X majorates the Alexander-Fox norms derived from π1(X). AMS Classification 57M20; 57M05
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تاریخ انتشار 2002