We determine all hyperbolic 3-manifolds M such that M(π ) contains a Klein bottle, M(τ ) contains an essential torus, and (π, τ ) = 5. As a corollary, we prove that if a hyperbolic 3-manifold M has two slopes π and τ on its boundary torus such that M(π ) is a lens space containing a Klein bottle and M(τ ) is toroidal, then (π, τ ) ≤ 4.
IntroductionLet M be a compact, connected, orientable 3-manifold with a torus boundary component ∂ 0 M. A slope on ∂ 0 M is the isotopy class of an essential simple closedis obtained from M by gluing a solid torus V γ along ∂ 0 M so that γ bounds a meridional disk of V γ . For two slopes γ 1 , γ 2 on ∂ 0 M, denote by (γ 1 , γ 2 ) the distance between the slopes, which is their geometric intersection number.We shall say that a 3-manifold M is hyperbolic if M with its boundary tori removed admits a complete hyperbolic structure with totally geodesic boundary. A Dehn filling on M is said to be exceptional if it produces a nonhyperbolic 3-manifold, which is either reducible, boundary-reducible, annular, toroidal, or a small Seifert fiber space. It is a well-known theorem of Thurston that there are only finitely many exceptional Dehn fillings on each boundary torus of M.Gordon and Wu [2008] determined all hyperbolic 3-manifolds admitting two toroidal Dehn fillings at distance 4 or 5. In this paper, we determine all hyperbolic 3-manifolds M admitting two Dehn fillings at distance 5, one of which yields a Klein bottle, the other yielding an essential torus.Following [Martelli and Petronio 2006], we use N to denote the magic manifold, the exterior of the chain link with three components in S 3 , shown in Figure 1. Using the standard meridian-longitude framing on each boundary component of N , we identify a slope γ with a number in ޑ ∪ {1/0}. We denote by N (r ) the result of MSC2000: 57M50.