Presentations for groups acting on simply-connected complexes
نویسندگان
چکیده
منابع مشابه
Groups acting on CAT(0) cube complexes
We show that groups satisfying Kazhdan’s property (T) have no unbounded actions on nite dimensional CAT(0) cube complexes, and deduce that there is a locally CAT(−1) Riemannian manifold which is not homotopy equivalent to any nite dimensional, locally CAT(0) cube complex. AMS Classi cation numbers Primary: 20F32 Secondary: 20E42, 20G20
متن کاملGroups Acting on CAT (0) Square Complexes
We study groups acting on CAT (0) square complexes. In particular we show if Y is a nonpositively curved (in the sense of A. D. Alexandrov) finite square complex and the vertex links of Y contain no simple loop consisting of five edges, then any subgroup of π1(Y ) either is virtually free abelian or contains a free group of rank two. In addition we discuss when a group generated by two hyperbol...
متن کاملMean eigenvalues for simple, simply connected, compact Lie groups
We determine for each of the simple, simply connected, compact and complex Lie groups SU(n), Spin(4n+2) and E6 that particular region inside the unit disk in the complex plane which is filled by their mean eigenvalues. We give analytical parameterizations for the boundary curves of these so-called trace figures. The area enclosed by a trace figure turns out to be a rational multiple of π in eac...
متن کاملUnramified Cohomology of Classifying Varieties for Exceptional Simply Connected Groups
Let BG be a classifying variety for an exceptional simple algebraic group G. We compute the degree 3 unramified Galois cohomology of BG with values in (Q/Z)′(2) over a nearly arbitrary field F . Combined with a paper by Merkurjev, this completes the computation of these cohomology groups for G semisimple simply connected over (nearly) all fields. Let G be an algebraic group over a field F with ...
متن کاملA Character Formula for Representations of Loop Groups Based on Non-simply Connected Lie Groups
In this paper we compute characters of certain irreducible representations of loop groups based on non simply connected Lie groups. Apart from a general representation theoretic interest, our motivation to study these characters comes from the fact that they appear naturally in the theory of moduli spaces of semistable principal bundles over elliptic curves. The characters of highest weight rep...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 1984
ISSN: 0022-4049
DOI: 10.1016/0022-4049(84)90009-4