Abstract
Let G be a group that admits a cocompact classifying space for proper actions X. We derive a formula for the Bredon cohomological dimension for proper actions of G in terms of the relative cohomology with compact support of certain pairs of subcomplexes of X. We use this formula to compute the Bredon cohomological dimension for proper actions of fundamental groups of non-positively curved simple complexes of finite groups. As an application we show that if a virtually torsion-free group acts properly and chamber transitively on a building, its virtual cohomological dimension coincides with its Bredon cohomological dimension. This covers the case of Coxeter groups and graph products of finite groups.
Funding source: Danmarks Grundforskningsfond
Award Identifier / Grant number: Centre for Symmetry and Deformation (DNRF92)
Funding source: Ministerio de Educación, Cultura y Deporte
Award Identifier / Grant number: MTM2010-19938-C03-03
Funding statement: The first author was supported by the Danish National Research Foundation through the Centre for Symmetry and Deformation (DNRF92) and the second by Gobierno de Aragón, European Regional Development Funds and Ministerio de Educación, Cultura y Deporte through MTM2010-19938-C03-03.
References
[1] Abramenko P. and Brown K. S., Buildings. Theory and applications, Grad. Texts in Math. 248, Springer-Verlag, New York 2008. 10.1007/978-0-387-78835-7Search in Google Scholar
[2] Aramayona J. and Martínez-Pérez C., The proper geometric dimension of the mapping class group, Algebr. Geom. Topol. 14 (2014), no. 1, 217–227. 10.2140/agt.2014.14.217Search in Google Scholar
[3] Brady N., Leary I. and Nucinkis B., On algebraic and geometric dimensions for groups with torsion, J. Lond. Math. Soc. (2) 64 (2001), 489–500. 10.1112/S002461070100240XSearch in Google Scholar
[4] Bredon G. E., Equivariant cohomology theories, Lecture Notes in Math. 34, Springer-Verlag, Berlin 1967. 10.1007/BFb0082690Search in Google Scholar
[5] Bridson M. R. and Haefliger A., Metric spaces of non-positive curvature, Grundlehren Math. Wiss. 319, Springer-Verlag, Berlin 1999. 10.1007/978-3-662-12494-9Search in Google Scholar
[6] Brown K. S., Cohomology of groups, Grad. Texts in Math. 87, Springer-Verlag, New York 1982. 10.1007/978-1-4684-9327-6Search in Google Scholar
[7] Davis M., Buildings are CAT(0), Geometry and cohomology in group theory, London Math. Soc. Lecture Note Ser. 252, Cambridge University Press, Cambridge (1998), 108–123. 10.1017/CBO9780511666131.009Search in Google Scholar
[8] Davis M., The cohomology of a Coxeter group with group ring coefficients, Duke J. Math. 91 (1998), no. 2, 297–314. 10.1215/S0012-7094-98-09113-XSearch in Google Scholar
[9] Davis M., The geometry and topology of Coxeter groups, London Math. Soc. Monogr. Ser. 32, Princeton University Press, Princeton 2008. Search in Google Scholar
[10] Davis M., Dymara J., Januszkiewicz T., Meier J. and Okun B., Compactly supported cohomology of buildings, Comment. Math. Helv. 85 (2010), no. 3, 551–582. 10.4171/CMH/205Search in Google Scholar
[11] Degrijse D., Bredon cohomological dimensions for proper actions and Mackey functors, Forum Math. (2014), 10.1515/forum-2014-0003. 10.1515/forum-2014-0003Search in Google Scholar
[12] Dranishnikov A., On the virtual cohomological dimensions of Coxeter groups, Proc. Amer. Math. Soc 125 (1997), no. 7, 1885–1891. 10.1090/S0002-9939-97-04106-3Search in Google Scholar
[13] Dranishnikov A., Boundaries of Coxeter groups and simplicial complexes with given links, J. Pure Appl. Algebra 137 (1999), no. 2, 139–151. 10.1016/S0022-4049(97)00202-8Search in Google Scholar
[14] Fluch M., On Bredon (co-)homological dimensions of groups, Ph.D. thesis, University of Southampton, 2011. Search in Google Scholar
[15] Holm H., Gorenstein homological dimensions, J. Pure Appl. Algebra 189 (2004), 167–193. 10.1016/j.jpaa.2003.11.007Search in Google Scholar
[16] Kropholler P., Martínez-Pérez C. and Nucinkis B., Cohomological finiteness conditions for elementary amenable groups, J. reine angew. Math. 637 (2009), 49–62. 10.1515/CRELLE.2009.090Search in Google Scholar
[17] Kropholler P. and Wall C., Group actions on algebraic cell complexes, Publ. Mat. 55 (2011), no. 1, 3–18. 10.5565/PUBLMAT_55111_01Search in Google Scholar
[18] Leary I. and Nucinkis B., Some groups of type VF, Invent. Math. 151 (2003), no. 1, 135–162. 10.1007/s00222-002-0254-7Search in Google Scholar
[19] Lück W., Transformation groups and algebraic K-theory, Lecture Notes in Math. 1408, Springer-Verlag, Berlin 1989. 10.1007/BFb0083681Search in Google Scholar
[20] Lück W., The type of the classifying space for a family of subgroups, J. Pure Appl. Algebra 149 (2000), 177–203. 10.1016/S0022-4049(98)90173-6Search in Google Scholar
[21] Lück W., Survey on classifying spaces for families of subgroups, Infinite groups. Geometric, combinatorial and dynamical aspects (Gaeta 2003), Progr. Math. 248, Birkhäuser-Verlag, Basel (2005), 269–322. 10.1007/3-7643-7447-0_7Search in Google Scholar
[22] Lück W. and Meintrup D., On the universal space for group actions with compact isotropy, Geometry and topology (Aarhus 1998), Contemp. Math. 258, American Mathematical Society, Providence (2000), 293–305. 10.1090/conm/258/1778113Search in Google Scholar
[23] Martínez-Pérez C. and Nucinkis B., Cohomological dimension of Mackey functors for infinite groups, J. Lond. Math. Soc. (2) 74 (2006), 379–396. 10.1112/S0024610706023143Search in Google Scholar
[24] Nucinkis B., Cohomology relative to a G-set and finiteness conditions, Topology Appl. 92 (1999), no. 2, 153–171. 10.1016/S0166-8641(97)00234-4Search in Google Scholar
[25]
John-Green S. St.,
On the Gorenstein and
[26] Vogtmann K., Automorphisms of free groups and outer space, Geom. Dedicata 94 (2002), no. 1, 1–31. 10.1023/A:1020973910646Search in Google Scholar
© 2016 by De Gruyter
Articles in the same Issue
- Frontmatter
- Singularities with 𝔾m-action and\break the log minimal model program for ℳ¯g
- Normal functions, Picard--Fuchs equations, and elliptic fibrations on K3 surfaces
- Degrees of strongly special subvarieties and the André–Oort conjecture
- Ambitoric geometry I: Einstein metrics and extremal ambikähler structures
- The closure of spectral data for constant mean curvature tori in 𝕊3
- Modular p-adic L-functions attached to real quadratic fields and arithmetic applications
- Dimension invariants for groups admitting a cocompact model for proper actions
Articles in the same Issue
- Frontmatter
- Singularities with 𝔾m-action and\break the log minimal model program for ℳ¯g
- Normal functions, Picard--Fuchs equations, and elliptic fibrations on K3 surfaces
- Degrees of strongly special subvarieties and the André–Oort conjecture
- Ambitoric geometry I: Einstein metrics and extremal ambikähler structures
- The closure of spectral data for constant mean curvature tori in 𝕊3
- Modular p-adic L-functions attached to real quadratic fields and arithmetic applications
- Dimension invariants for groups admitting a cocompact model for proper actions