A homological estimate for the Thurston norm
نویسنده
چکیده
We establish a new homological lower bound for the Thurston norm on 1-cohomology of 3-manifolds. This generalizes previous results of C. McMullen, S. Harvey, and the author. We also establish an analogous lower bound for 1-cohomology of 2-dimensional CW-complexes. AMS Classification 57M27, 57M20, 57M05
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