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Eleven papers published by Geometry & Topology Publications
Posted:
May 24, 2011 10:00 AM


Eight papers have been published by Algebraic & Geometric Topology
(1) Algebraic & Geometric Topology 11 (2011) 13231343 The moduli space of hex spheres by AldoHilario CruzCota URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p042.xhtml DOI: 10.2140/agt.2011.11.1323
(2) Algebraic & Geometric Topology 11 (2011) 13451359 Nonsmoothable group actions on spin 4manifolds by Kazuhiko Kiyono URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p043.xhtml DOI: 10.2140/agt.2011.11.1345
(3) Algebraic & Geometric Topology 11 (2011) 13611403 Units of equivariant ring spectra by Rekha Santhanam URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p044.xhtml DOI: 10.2140/agt.2011.11.1361
(4) Algebraic & Geometric Topology 11 (2011) 14051433 Complete graphs whose topological symmetry groups are polyhedral by Erica Flapan, Blake Mellor and Ramin Naimi URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p045.xhtml DOI: 10.2140/agt.2011.11.1405
(5) Algebraic & Geometric Topology 11 (2011) 14351443 Dividing sets as nodal sets of an eigenfunction of the Laplacian by Samuel T Lisi URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p046.xhtml DOI: 10.2140/agt.2011.11.1435
(6) Algebraic & Geometric Topology 11 (2011) 14451454 On links with locally infinite Kakimizu complexes by Jessica E Banks URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p047.xhtml DOI: 10.2140/agt.2011.11.1445
(7) Algebraic & Geometric Topology 11 (2011) 14551469 Systoles of hyperbolic manifolds by Mikhail V Belolipetsky and Scott A Thomson URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p048.xhtml DOI: 10.2140/agt.2011.11.1455
(8) Algebraic & Geometric Topology 11 (2011) 14711495 Complexes and exactness of certain Artin groups by Erik Guentner and Graham A Niblo URL: http://www.msp.warwick.ac.uk/agt/2011/1103/p049.xhtml DOI: 10.2140/agt.2011.11.1471
Three papers have been published by Geometry & Topology
(9) Geometry & Topology 15 (2011) 707733 Orthospectra of geodesic laminations and dilogarithm identities on moduli space by Martin Bridgeman URL: http://www.msp.warwick.ac.uk/gt/2011/1502/p020.xhtml DOI: 10.2140/gt.2011.15.707
(10) Geometry & Topology 15 (2011) 735764 Concerning the existence of Einstein and Ricci soliton metrics on solvable Lie groups by Michael Jablonski URL: http://www.msp.warwick.ac.uk/gt/2011/1502/p021.xhtml DOI: 10.2140/gt.2011.15.735
(11) Geometry & Topology 15 (2011) 765826 Targetlocal Gromov compactness by Joel W Fish URL: http://www.msp.warwick.ac.uk/gt/2011/1502/p022.xhtml DOI: 10.2140/gt.2011.15.765
Abstracts follow
(1) The moduli space of hex spheres by AldoHilario CruzCota
A hex sphere is a singular Euclidean sphere with four cone points whose cone angles are (integer) multiples of 2pi/3 but less than 2pi. We prove that the Moduli space of hex spheres of unit area is homeomorphic to the the space of similarity classes of Voronoi polygons in the Euclidean plane. This result gives us as a corollary that each unitarea hex sphere M satisfies the following properties: (1) it has an embedded (open Euclidean) annulus that is disjoint from the singular locus of M; (2) it embeds isometrically in the 3dimensional Euclidean space as the boundary of a tetrahedron; and (3) there is a simple closed geodesic gamma in M such that a fractional Dehn twist along gamma converts M to the double of a parallelogram.
(2) Nonsmoothable group actions on spin 4manifolds by Kazuhiko Kiyono
We show that every closed, simply connected, spin topological 4manifold except the 4sphere and the product of the 2sphere with itself admits a homologically trivial, pseudofree, locally linear action of cyclic group of any sufficiently large prime order which is nonsmoothable for any possible smooth structure.
(3) Units of equivariant ring spectra by Rekha Santhanam
It is well known that very special Gammaspaces and grouplike E_infinityspaces both model connective spectra. Both these models have equivariant analogues in the case when the group acting is finite. Shimakawa defined the category of equivariant Gammaspaces and showed that special equivariant Gammaspaces determine positive equivariant spectra. Costenoble and Waner [Trans. Amer. Math. Soc. 326 (1991) 485505] showed that grouplike equivariant E_infinityspaces determine connective equivariant spectra.
We show that with suitable model category structures the category of equivariant Gammaspaces is Quillen equivalent to the category of equivariant E_infinityspaces. We define the units of equivariant ring spectra in terms of equivariant Gammaspaces and show that the units of an equivariant ring spectrum determines a connective equivariant spectrum.
(4) Complete graphs whose topological symmetry groups are polyhedral by Erica Flapan, Blake Mellor and Ramin Naimi
We determine for which m the complete graph K_m has an embedding in the threesphere whose topological symmetry group is isomorphic to one of the polyhedral groups A_4, A_5 or S_4.
(5) Dividing sets as nodal sets of an eigenfunction of the Laplacian by Samuel T Lisi
We show that for any convex surface S in a contact 3manifold, there exists a metric on S and a neighbourhood contact isotopic to S times I with the contact structure given by ker(u dt  star du) where u is an eigenfunction of the Laplacian on S and star is the Hodge star from the metric on S. This answers a question posed by Komendarczyk [Trans. Amer. Math. Soc. 358 (2006) 23992413].
(6) On links with locally infinite Kakimizu complexes by Jessica E Banks
We show that the Kakimizu complex of a knot may be locally infinite, answering a question of PrzytyckiSchultens. We then prove that if a link L only has connected Seifert surfaces and has a locally infinite Kakimizu complex then L is a satellite of either a torus knot, a cable knot or a connected sum, with winding number 0.
(7) Systoles of hyperbolic manifolds by Mikhail V Belolipetsky and Scott A Thomson
We show that for every n>=2 and any epsilon > 0 there exists a compact hyperbolic nmanifold with a closed geodesic of length less than epsilon. When epsilon is sufficiently small these manifolds are nonarithmetic, and they are obtained by a generalised inbreeding construction which was first suggested by Agol for n = 4. We also show that for n >= 3 the volumes of these manifolds grow at least as 1/epsilon^{n2} when epsilon > 0.
(8) Complexes and exactness of certain Artin groups by Erik Guentner and Graham A Niblo
In his work on the Novikov conjecture, Yu introduced Property A as a readily verified criterion implying coarse embeddability. Studied subsequently as a property in its own right, Property A for a discrete group is known to be equivalent to exactness of the reduced group C^*algebra and to the amenability of the action of the group on its StoneCech compactification. In this paper we study exactness for groups acting on a finite dimensional CAT(0) cube complex. We apply our methods to show that Artin groups of type FC are exact. While many discrete groups are known to be exact the question of whether every Artin group is exact remains open.
(9) Orthospectra of geodesic laminations and dilogarithm identities on moduli space by Martin Bridgeman
Given a measured lamination lambda on a finite area hyperbolic surface we consider a natural measure M_lambda on the real line obtained by taking the pushforward of the volume measure of the unit tangent bundle of the surface under an intersection function associated with the lamination. We show that the measure M_lambda gives summation identities for the Rogers dilogarithm function on the moduli space of a surface.
(10) Concerning the existence of Einstein and Ricci soliton metrics on solvable Lie groups by Michael Jablonski In this work we investigate solvable and nilpotent Lie groups with special metrics. The metrics of interest are leftinvariant Einstein and algebraic Ricci soliton metrics. Our main result shows that one may determine the existence of a such a metric by analyzing algebraic properties of the Lie algebra and infinitesimal deformations of any initial metric.
Our second main result concerns the isometry groups of such distinguished metrics. Among the completely solvable unimodular Lie groups (this includes nilpotent groups), if the Lie group admits such a metric, we show that the isometry group of this special metric is maximal among all isometry groups of leftinvariant metrics.
(11) Targetlocal Gromov compactness by Joel W Fish We prove a version of Gromov's compactness theorem for pseudoholomorphic curves which holds locally in the target symplectic manifold. This result applies to sequences of curves with an unbounded number of free boundary components, and in families of degenerating target manifolds which have unbounded geometry (eg no uniform energy threshold). Core elements of the proof regard curves as submanifolds (rather than maps) and then adapt methods from the theory of minimal surfaces.
Geometry & Topology Publications is an imprint of Mathematical Sciences Publishers



