Products of Positive Dehn-twists on Surfaces Feng Luo
نویسنده
چکیده
Theorem 2. Suppose Σg,n is a compact orientable surface of genus g with n boundary components. Let {a1, ...., a3g−3+2n} be a 3-holed sphere decomposition of the surface where ∂Σg,n = a3g−2+n ∪ ... ∪ a3g−3+2n. Then each orientation preserving homeomorphism of the surface which is the identity map on ∂Σg,n is isotopic to a composition qp where p is positive and q is a composition of negative Dehn-twists on ai’s.
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