设(M;H1,H2;F0)为带边3-流形M的-个SD-分解.称该分解为可约的(或弱可约的)若存在本质圆片D1包含于H1,D2包含于H2使得δD1,δD2包含于F0并且δD1=δD2(或δD1∩δD2=0).称(M;H1,H2;F0)为内亏格1若F0为穿孔环面.本文主要结果:一个弱可约的内亏格1的SD一分解或是可约的或是双经的.
Let (M; H1, H2; Fo) be a SD-splitting for bordered 3-manifold M. The splitting is reducible (weakly reducible, respectively) if there exist essential disks D1 belong to H1 and D2 belong to H2 such that δD1,δD2 belong to Fo and δD1 =δD2 (δD1 ∩ δD2 =φ, respectively). A SD-splitting (M; H1, H2; Fo) for bordered 3-manifold M is of inner genus 1 if Fo is a punctured torus. In the present paper, we show that a weakly reducible SD-splitting of inner genus 1 is either reducible or bilongitudional.