THE HOMOMORPHIC IMAGES OF INFINITE SYMMETRICAL GROUPS

Authors
Citation
U. Felgner et F. Haug, THE HOMOMORPHIC IMAGES OF INFINITE SYMMETRICAL GROUPS, Forum mathematicum, 5(5), 1993, pp. 505-520
Citations number
18
Categorie Soggetti
Mathematics,Mathematics,Mathematics
Journal title
ISSN journal
09337741
Volume
5
Issue
5
Year of publication
1993
Pages
505 - 520
Database
ISI
SICI code
0933-7741(1993)5:5<505:THIOIS>2.0.ZU;2-A
Abstract
We give a solution of De Bruijn's problem as to which homomorphic imag es of an infinite symmetric group S(kappa) are embeddable into S(kappa ). We prove (in ZF + V = L) that S(kappa)/S(lambda)(kappa) can be embe dded into S(kappa) if and only if lambda < Cf(kappa). We also discuss F. Clare's problem whether S(kappa)/S(kappa)(kappa) is a universal gro up. We prove that it is consistent with ZFC that S(omega)/S(omega)(ome ga)) is not universal. However S(kappa)/S(kappa)(kappa) is almost univ ersal, since the group S(kappa+)(kappa+) of all bounded permutations O f kappa+ embeds into it when kappa is regular.