Hostname: page-component-5c6d5d7d68-wtssw Total loading time: 0 Render date: 2024-08-22T02:23:46.671Z Has data issue: false hasContentIssue false

Stable summands of U(n)

Published online by Cambridge University Press:  14 November 2011

M. C. Crabb
Affiliation:
Department of Mathematical Sciences, University of Aberdeen AB24 3QY, Scotland, U.K.
J. R. Hubbuck
Affiliation:
Department of Mathematical Sciences, University of Aberdeen AB24 3QY, Scotland, U.K.
J. A. W. McCall
Affiliation:
School of Computer and Mathematical Sciences, The Robert Gordon University, Aberdeen AB25 1HG, Scotland, U.K.

Synopsis

The special unitary group SU(n) has the stable homotopy type of a wedge of n − 1 finite complexes. The ‘first’ of these complexes is ΣℂPn–1, which is well known to be indecomposable at the prime 2 whether n is finite or infinite. We show that the ‘second’ finite complex is again indecomposable at the prime 2 when n is finite, but splits into a wedge of two pieces when n is infinite.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1Alghamdi, Mohamed Ali, Crabb, M. C. and Hubbuck, J. R.. Representations of the homology of BV and the Steenrod Alebra I. In Adams Memorial Symposium on Algebraic Topology, Vol. 2, London Mathematical Society Lecture Note Series 176, 217–34 (Cambridge: Cambridge University Press, 1992).Google Scholar
2Baker, A., Clarke, F., Ray, N. and Schwartz, L.. On the Kummer congruence and the stable homotopy of BU. Trans. Amer. Math. Soc. 316 (1989), 385432.Google Scholar
3Crabb, M. C.. ℤ/2-Homotopy Theory, London Mathematical Society Lecture Note Series 44 (Cambridge: Cambridge University Press, 1980).CrossRefGoogle Scholar
4Crabb, M. C.. On the stable splitting of U(n) and ΩU(n). Algebraic Topology Barcelona 1986, Lecture Notes in Mathematics 1298, 3553 (Berlin: Springer, 1987).Google Scholar
5Crabb, M. C. and Xu, Kai. Quadratic spaces. Math. Z. (to appear).Google Scholar
6Eccles, P. J. and Mitchell, W. P. R.. Splitting Σ(ℂP × ℂP)localized at 2. Quart. J. Math. Oxford 39 (1988), 285–9.CrossRefGoogle Scholar
7Hubbuck, J. R.. Numerical forms. J. London Math. Soc. 55 (1997), 6775.CrossRefGoogle Scholar
8McCall, J. A. W.. Stable indecomposability of certain summands in Miller's splitting of the special unitary and symplectic groups (Ph.D. Thesis, University of Amerdeen, 1991).Google Scholar
9Miller, H.. Stable splittings of Stiefel manifolds. Topology 24 (1985), 411–19.Google Scholar