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We define a new integer invariant of a finite graph G, the freeness index, that measures the extent to which G can be embedded in the 3-sphere so that it and its subgraphs have ``simple" complements, i.e., complements which are homeomorphic to a connect-sum of handlebodies. We relate the freeness index to questions of embedding graphs into surfaces, in particular to the orientable cycle double cover conjecture. We show that a cubic graph satisfying the orientable double cycle cover conjecture has freeness index at least two.

This is the first of a three parts paper providing full details for our previous announcement in Pr\'epublications Orsay 2007-16, arXiv:0711.3579. Here we prove the results stated in the title.

v1: In this paper, we will give an elementary proof by the Heegaard splittings of the 3-dimentional Poincare conjecture in point of view of PL topology. This paper is of the same theory in [4](1983) excluding the last three lines of the proof of the main theorem. v2: This paper gives the basic result of [1](1997), i.e., a handle sliding and a band move of Heegaard diagrams correspond to a replacement and a substitution in relations of the fundamental groups derived from Heegaard diagrams, respectively (Theorem 12). Corollary 13 is a new addition for the homotopy 3-sphere., Comment: v1:3 pages with 3 figures v2:9 pages with 9 figures

We show that a certain geometric property, the QSF introduced by S. Brick and M. Mihalik, is universally true for {\ibf all} finitely presented groups $\Gamma$. One way of defining this property is the existence of a smooth compact manifold $M$ with $\pi_1 M = \Gamma$, such that $\tilde M$ is geometrically simply-connected ({\it i.e.} without handles of index $\lambda = 1$). There are also alternative, more group-theoretical definitions, which are presentation independent. But $\Gamma \in {\rm QSF}$ is not only a universal property, it is quite highly non-trivial too; its very special case for $\Gamma = \pi_1 M^3$ (where it means $\pi_1^{\infty} \tilde M^3 = 0$) is actually already known, as a corollary of G. Perelman's big breakthrough on the Geometrization of 3-Manifolds.

Let ${\mathcal H}$ be the group of isotopy classes of orientation preserving homeomorphisms of $S^3$ that preserve a Heegaard splitting of genus two. In this paper, we use a tree in the barycentric subdivision of the disk complex of a handlebody of the splitting to obtain a finite presentation of ${\mathcal H}$.

This manuscript contains a detailed proof of the Poincare Conjecture. The arguments we present here are expanded versions of the ones given by Perelman in his three preprints posted in 2002 and 2003. This is a revised version taking in account the comments of the referees and others. It has been reformatted in the AMS book style., Comment: 493 pages with over 30 figures and 3 pages of front material

We give a short proof of Bing's characterization of $S^3$: a compact, connected 3-manifold $M$ is $S^3$ if and only if every knot in $M$ is isotopic into a ball., Comment: To appear in Proceedings of the AMS, 2 pages

It is well known that a three dimensional (closed, connected and compact) manifold is obtained by identifying boundary faces from a polyhedron P. The study of (\partial P)/~, the boundary \partial P with the polygonal faces identified in pairs leads us to the following conclusion: either a three dimensional manifold is homeomorphic to a sphere or to a polyhedron P with its boundary faces identified in pairs so that (\partial P)/~ is a finite number of internally flat complexes attached to each other along the edges of a finite graph that contains at least one closed circuit. Each of those internally flat complexes is obtained from a polygon where each side may be identified with more than one different sides. Moreover, Euler characteristic of (\partial P)/~ is equal to one and the fundamental group of (\partial P)/~ is not trivial.

We prove that the three-sphere recognition problem lies in the complexity class NP. Our work relies on Thompson's original proof that the problem is decidable [Math. Res. Let., 1994], Casson's version of her algorithm, and recent results of Agol, Hass, and Thurston [ArXiv, 2002]., Comment: 36 pages, 12 figures

Understanding non-Haken 3-manifolds is central to many current endeavors in 3-manifold topology. We describe some results for closed orientable surfaces in non-Haken manifolds, and extend Fox's theorem for submanifolds of the 3-sphere to submanifolds of general non-Haken manifolds. In the case where the submanifold has connected boundary, we show also that the boundary-connected sum decomposition of the submanifold can be aligned with such a structure on the submanifold's complement., Comment: 10 pages

It is well known that a compact two dimensional surface is homeomorphic to a polygon with the edges identified in pairs. This paper not only presents a new proof of this statement but also generalizes it for any connected n-dimensional stellar manifold with a finite number of vertices.

This paper proves that any compact, closed, simply connected and connected three dimensional stellar manifold is stellar equivalent to the three dimensional sphere., Comment: Th. 2.8 was wrong in version 1 that made the proof incomplete. It was fixed in version 2. The definition of simple connectivity (Definition 10) was too strong in version 2. It was fixed in version 3. Versions 4 has minor editorial changes that make presentation more clear and precise . Definition 3 (Cutting along a simplex) is fixed in Version 5 . Versions 6, 7 and 8 contain an improved presentation of the main result