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 1 24th August 16:51 geometry and topology External User   Posts: 1 Seven papers published by Geometry & Topology Publications Four papers have been published by Algebraic and Geometric Topology (1) Algebraic & Geometric Topology 6 (2006) 1429-1457 Holomorphic discs and sutured manifolds by Andras Juhasz URL: http://www.msp.warwick.ac.uk/agt/2006/06/p052.xhtml DOI: 10.2140/agt.2006.6.1429 (2) Algebraic & Geometric Topology 6 (2006) 1459-1469 The Karoubi envelope and Lee's degeneration of Khovanov homology by Dror Bar-Natan and Scott Morrison URL: http://www.msp.warwick.ac.uk/agt/2006/06/p053.xhtml DOI: 10.2140/agt.2006.6.1459 (3) Algebraic & Geometric Topology 6 (2006) 1471-1489 Cohomology of preimages with local coefficients by Daciberg Goncalves and Peter Wong URL: http://www.msp.warwick.ac.uk/agt/2006/06/p054.xhtml DOI: 10.2140/agt.2006.6.1471 (4) Algebraic & Geometric Topology 6 (2006) 1491-1517 Cosmetic surgeries on genus one knots by Jiajun Wang URL: http://www.msp.warwick.ac.uk/agt/2006/06/p055.xhtml DOI: 10.2140/agt.2006.6.1491 Three papers have been published by Geometry and Topology (5) Geometry & Topology 10 (2006) 1373-1389 Dense embeddings of surface groups by Emmanuel Breuillard, Tsachik Gelander, Juan Souto and Peter Storm URL: http://www.msp.warwick.ac.uk/gt/2006/10/p034.xhtml DOI: 10.2140/gt.2006.10.1373 (6) Geometry & Topology 10 (2006) 1391-1424 On the chain-level intersection pairing for PL manifolds by J E McClure URL: http://www.msp.warwick.ac.uk/gt/2006/10/p035.xhtml DOI: 10.2140/gt.2006.10.1391 (7) Geometry & Topology 10 (2006) 1425-1452 Stabilization in the braid groups II: Transversal simplicity of knots by Joan S Birman and William W Menasco URL: http://www.msp.warwick.ac.uk/gt/2006/10/p036.xhtml DOI: 10.2140/gt.2006.10.1425 Abstracts follow (1) Holomorphic discs and sutured manifolds by Andras Juhasz In this paper we construct a Floer-homology invariant for a natural and wide class of sutured manifolds that we call balanced. This generalizes the Heegaard Floer hat theory of closed three-manifolds and links. Our invariant is unchanged under product decompositions and is zero for nontaut sutured manifolds. As an application, an invariant of Seifert surfaces is given and is computed in a few interesting cases. (2) The Karoubi envelope and Lee's degeneration of Khovanov homology by Dror Bar-Natan and Scott Morrison We give a simple proof of Lee's result from [Adv. Math. 179 (2005) 554-586], that the dimension of the Lee variant of the Khovanov homology of a c-component link is 2^c, regardless of the number of crossings. Our method of proof is entirely local and hence we can state a Lee-type theorem for tangles as well as for knots and links. Our main tool is the Karoubi envelope of the cobordism category'', a certain enlargement of the cobordism category which is mild enough so that no information is lost yet strong enough to allow for some simplifications that are otherwise unavailable. (3) Cohomology of preimages with local coefficients by Daciberg Goncalves and Peter Wong Let M,N and B\subset N be compact smooth manifolds of dimensions n+k,n and \ell, respectively. Given a map f from M to N, we give homological conditions under which g^{-1}(B) has nontrivial cohomology (with local coefficients) for any map g homotopic to f. We also show that a certain cohomology class in H^j(N,N-B) is Poincare dual (with local coefficients) under f^* to the image of a corresponding class in H_{n+k-j}(f^{-1}(B)) when f is transverse to B. This generalizes a similar formula of D\,Gottlieb in the case of simple coefficients. (4) Cosmetic surgeries on genus one knots by Jiajun Wang In this paper, we prove that there are no truly cosmetic surgeries on genus one classical knots. If the two surgery slopes have the same sign, we give the only possibilities of reflectively cosmetic surgeries. The result is an application of Heegaard Floer theory and number theory. (5) Dense embeddings of surface groups by Emmanuel Breuillard, Tsachik Gelander, Juan Souto and Peter Storm We discuss dense embeddings of surface groups and fully residually free groups in topological groups. We show that a compact topological group contains a nonabelian dense free group of finite rank if and only if it contains a dense surface group. Also, we obtain a characterization of those Lie groups which admit a dense faithfully embedded surface group. Similarly, we show that any connected semisimple Lie group contains a dense copy of any fully residually free group. (6) On the chain-level intersection pairing for PL manifolds by J E McClure Let M be a compact oriented PL manifold and let C_*M be its PL chain complex. The domain of the chain-level intersection pairing is a subcomplex G of C_*M\otimes C_*M. We prove that G is a full'' subcomplex, that is, the inclusion of G in C_*M \otimes C_*M is a quasi-isomorphism. An ****ogous result is true for the domain of the iterated intersection pairing. Using this, we show that the intersection pairing gives C_*M a structure of partially defined commutative DGA, which in particular implies that C_*M is canonically quasi-isomorphic to an E_\infty chain algebra. (7) Stabilization in the braid groups II: Transversal simplicity of knots by Joan S Birman and William W Menasco The main result of this paper is a negative answer to the question: are all transversal knot types transversally simple? An ******** infinite family of examples is given of closed 3-braids that define transversal knot types that are not transversally simple. The method of proof is topological and indirect.