Expand all Collapse all | Results 1 - 6 of 6 |
1. CMB 2012 (vol 57 pp. 326)
On Zero-divisors in Group Rings of Groups with Torsion Nontrivial pairs of zero-divisors in group rings are
introduced and discussed. A problem on the existence of nontrivial
pairs of zero-divisors in group rings of free Burnside groups of odd
exponent $n \gg 1$ is solved in the affirmative. Nontrivial pairs of
zero-divisors are also found in group rings of free products of groups
with torsion.
Keywords:Burnside groups, free products of groups, group rings, zero-divisors Categories:20C07, 20E06, 20F05, , 20F50 |
2. CMB 2011 (vol 56 pp. 395)
Coessential Abelianization Morphisms in the Category of Groups An epimorphism $\phi\colon G\to H$ of groups, where $G$ has rank $n$, is called
coessential if every (ordered) generating $n$-tuple of $H$ can be
lifted along $\phi$ to a generating $n$-tuple for $G$. We discuss this
property in the context of the category of groups, and establish a criterion
for such a group $G$ to have the property that its abelianization
epimorphism $G\to G/[G,G]$, where $[G,G]$ is the commutator subgroup, is
coessential. We give an example of a family of 2-generator groups whose
abelianization epimorphism is not coessential.
This family also provides counterexamples to the generalized Andrews--Curtis conjecture.
Keywords:coessential epimorphism, Nielsen transformations, Andrew-Curtis transformations Categories:20F05, 20F99, 20J15 |
3. CMB 2006 (vol 49 pp. 347)
Affine Completeness of Generalised Dihedral Groups In this paper we study affine completeness of generalised dihedral
groups. We give a formula for the number of unary compatible
functions on these groups, and we characterise for every $k \in~\N$
the $k$-affine complete generalised dihedral groups. We find that
the direct product of a $1$-affine complete group with itself need not
be $1$-affine complete. Finally, we give an example of a nonabelian
solvable affine complete group. For nilpotent groups we find a
strong necessary condition for $2$-affine completeness.
Categories:08A40, 16Y30, 20F05 |
4. CMB 2003 (vol 46 pp. 299)
A Basis of Bachmuth Type in the Commutator Subgroup of a Free Group We show here that the commutator subgroup of a free group of finite
rank poses a basis of Bachmuth's type.
Categories:20E05, 20F12, 20F05 |
5. CMB 2003 (vol 46 pp. 310)
Second Order Dehn Functions of Asynchronously Automatic Groups Upper bounds of second order Dehn functions of asynchronously
automatic groups are obtained.
Keywords:second order Dehn function, combing, asynchronously automatic group Categories:20E06, 20F05, 57M05 |
6. CMB 1998 (vol 41 pp. 231)
The growth series of compact hyperbolic Coxeter groups with 4 and 5 generators The growth series of compact hyperbolic Coxeter groups with 4 and 5
generators are explicitly calculated. The assertions of J.~Cannon
and Ph.~Wagreich for the 4-generated groups, that the poles of the
growth series lie
on the unit circle, with the exception of a single real reciprocal pair of
poles, are verified. We also verify that for the 5-generated groups, this
phenomenon fails.
Categories:20F05, 20F55 |