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Stefan Witzel's user avatar
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Stefan Witzel
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8 Answers

Score Activity Newest
13 votes

Fundamental Examples

  • examples
  • soft-question
  • big-picture
  • big-list
  • ho.history-overview
answered Apr 13, 2010 at 18:32
13 votes
Accepted

Cohomological dimension of torsion-free groups and its subgroups

  • gr.group-theory
  • homological-algebra
  • cohomology
  • group-cohomology
  • projective-resolution
answered Jul 15, 2021 at 19:35
8 votes

Quasisplit but not split semisimple groups

  • ag.algebraic-geometry
  • reference-request
  • gr.group-theory
  • algebraic-groups
answered Jul 7, 2021 at 5:19
4 votes

Finite models for torsion-free lattices

  • reference-request
  • at.algebraic-topology
  • gt.geometric-topology
  • lie-groups
  • symmetric-spaces
answered Feb 11, 2020 at 21:04
3 votes

Properly Discontinuous Action

  • riemann-surfaces
  • at.algebraic-topology
  • group-actions
  • gn.general-topology
answered Jun 30, 2011 at 21:15
2 votes

Is this the CAT(0) metric on an affine building?

  • mg.metric-geometry
  • alexandrov-geometry
  • buildings
answered Aug 29, 2011 at 13:16
1 vote

Angles and Busemann function in CAT(0)

  • gt.geometric-topology
  • mg.metric-geometry
answered Jul 2, 2021 at 14:39
1 vote

Homology software

  • at.algebraic-topology
  • big-list
  • mathematical-software
  • computational-topology
answered Jul 26, 2021 at 9:23
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