Planar-busting Curves on the Boundary of a Handlebody

Let Hn be an orientable handlebody of genus n. It has been proved that for n not less than 2, there exists an annulus-busting curve in δHm. In the present paper, we prove that for n not less than 2, there exists an essential simple closed curve C in OHm which intersects each essential planar surface in Hn non-emptily. Furthermore, we show that for n not less than 3, a pants-busting curve must also be an annulus-busting curve.

Subsurface 1-distance of the Handlebody

For a handlebody H w ith dH = 5, let F belong S be an essential connected subsurface of S. Let C（S） be the curve complex of S, AC（F） be the arc and curve complex of F , D（H） belong C（S） be the disk complex of H and πf（D （H ） ） belong AC（F） be the image of D （H） in AC （F）. We introduce the definition of subsurface 1-distance between the 1-simplices of AC（F） and show that under some hypothesis, πF（D（H） ） comes within subsurface 1-distance at most 4 of every 1-simplex of AC （F）.

A necessary and sufficient condition for a surface sum of two handlebodies to be a handlebody

The main results of the paper are that we give a necessary and sufficient condition for a surface sum of two handlebodies along a connected surface to be a handlebody as follows:(1)The annulus sum H=H1∪AH2 of two handlebodies H1 and H2 is a handlebody if and only if the core curve of A is a longitude for either H1 or H2;(2)Let H=H1∪Sg,b H2 be a surface sum of two handlebodies H1 and H2 along a connected surface S=Sg,b,b 1,ni=g(Hi)2,i=1,2.Suppose that S is incompressible in both H1 and H2.Then H is a handlebody if and only if there exists a basis J={J1,...,Jm}with a partition(J1,J2)of J such that J1 is primitive in H1 and J2 is primitive in H2.

On n-relator 3-manifolds Which Are Handlebodies

Let H be a handlebody, J={J 1, …, J n} a collection of 2 sided pairwise disjoint simple closed curves on H. The 3 manifold obtained from H by attaching 2 handles to H along the curves in J is called an n relator 3 manifold, and is denoted as H J. In this paper, a sufficient and necessary condition for H J to be a handlebody is described.

A standard form of incompressible surfaces in 3-dimensional handlebodies

Applying the Morse theory,we give a standard form for a class of surfaces which includes all the properly embedded incompressible surfaces in 3-dimensional handlebodies.We also give a necessary and sufficient condition to determine the incompressibility of such surfaces placed in our standard form.Our algorithm is practical.Several examples are given to test the algorithm.

On 3-Submanifolds of S3 Which Admit Complete Spanning Curve Systems

Let M be a compact connected 3-submanifold of the 3-sphere S^3 with one boundary component F such that there exists a collection of n pairwise disjoint connected orientable surfaces S = {S_1, ···, S_n} properly embedded in M, ?S = {?S_1, ···, ?S_n}is a complete curve system on F. We call S a complete surface system for M, and ?S a complete spanning curve system for M. In the present paper, the authors show that the equivalent classes of complete spanning curve systems for M are unique, that is, any complete spanning curve system for M is equivalent to ?S. As an application of the result,it is shown that the image of the natural homomorphism from the mapping class group M(M) to M(F) is a subgroup of the handlebody subgroup Hn.

SD-splittings for Some Bordered 3-Manifolds

In the present paper, we characterize the bordered 3-manifolds with genus 1 D-splittings and SD-splittings. We also describe a minimal genus SD-splitting for a handlebody and surface × I.