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13 votes
1 answer
370 views

Factorizing groups into a product of solvable subgroups

Does every finite group $G$ have a factorization $G=H_1\cdots H_k$ where the $H_i$ for $1\le i\le k$ are solvable subgroups of $G$ and $|G|=|H_1|\cdots |H_k|$ (equivalently, every element of $G$ is ...
Tom WIlde's user avatar
  • 787
7 votes
1 answer
256 views

Krasner–Kaloujnine universal embedding theorem for finitely generated groups?

The Krasner–Kaloujnine universal embedding theorem states that any group extension of a group $H$ by a group $A$ is isomorphic to a subgroup of the regular wreath product $A \operatorname{Wr} H$. When ...
tmh's user avatar
  • 775
8 votes
0 answers
190 views

Groups having exactly two non real-valued irreducible characters

This is an enlarged version of my question on MSE. It was suggested I ask here instead. Suppose the finite group $G$ has exactly two conjugacy classes that are not self-inverse (a conjugacy class is ...
Tom WIlde's user avatar
  • 787
10 votes
4 answers
1k views

Conjugation by elements of subgroups

Let $G$ be a group generated by a conjugacy class $C$. I am interested in studying this property: for every $x,y\in C$ there exists $h\in \langle x,y\rangle$ such that $y=hxh^{-1}$. Basically the ...
marcos's user avatar
  • 467
4 votes
2 answers
559 views

Groups whose derived length is logarithmic in the order?

Is there a class of solvable groups $G$ having a derived length $O(\log\lvert G\rvert)$? See Wikipedia for the definition of Big-Oh ($O$) and the definition of derived series of a group. Any help ...
User01's user avatar
  • 217
23 votes
2 answers
968 views

Solvable groups that are linear over $\mathbb{C}$ but not over $\mathbb{Q}$?

Let $\Gamma$ be a finitely generated finitely presented virtually solvable group. Assume that there exists an injective representation $\Gamma \to \operatorname{GL}_n(\mathbb{C})$. Is it true that ...
 V. Rogov's user avatar
  • 1,170
15 votes
1 answer
975 views

Is the infinite product of solvable groups amenable?

I am interested in the amenability properties of infinite products of solvable groups. The following facts are well-known: Any solvable group is amenable. The class of solvable groups is closed under ...
Asgar's user avatar
  • 153
18 votes
1 answer
752 views

Is solvability semi-decidable?

Let $G = \langle A \mid R \rangle$ be a finitely presented group, given by a finite presentation. If $G$ is abelian, then we can verify this fact: simply verify the fact that $[a, b] = 1$ for all ...
Carl-Fredrik Nyberg Brodda's user avatar
4 votes
0 answers
211 views

A different approach to proving a property of finite solvable groups

Edit: I'd be happy to hear any vague thoughts you might have, however far they may be from a complete solution! I asked this on math.stackexchange a couple of days ago, but it didn't attract any ...
semisimpleton's user avatar
0 votes
2 answers
359 views

Splitting of a finite group with no abelian subfactor in composition series

Let $G$ be a finite group with no abelian subfactor in its composition series. Is $G$ obtained from simple groups by iterating semidirect products? (Initially it was asked whether $G$ is a direct ...
User01's user avatar
  • 217
4 votes
1 answer
417 views

Is a solvable group satisfying a semigroup law?

Let $S$ be the free semigroup on the set $\{x_1,\ldots ,x_n\}$, where $n$ is a positive integer. Suppose that $\mu=\mu (x_1,\ldots ,x_n)$ and $\nu = \nu (x_1,\ldots ,x_n)$ are two elements in $S$. We ...
mahdi meisami's user avatar
15 votes
1 answer
620 views

Does $\mathbb{Q}$ embed into a finitely generated solvable group?

Does $\mathbb{Q}$ embed into a finitely generated solvable group? I've checked that $\mathbb{Q}$ is not a subgroup of any finitely generated metabelian group. I don't know how to show this (or ...
Josh F's user avatar
  • 545
2 votes
1 answer
132 views

Element that is in $\phi^{-1}(Z(F (G/F(G)))$

I'm studying an article but I'm not able to understand one of his statements. I have the following hypotheses: $G$ is a solvable group with trivial center, $J=\phi^{-1}(F(G/F(G)))$ and $J_2=\phi^{-1}(...
Thiago Luiz's user avatar
8 votes
2 answers
480 views

Abundancy index and non-solvable finite groups

Let $\sigma$ be the sum-of-divisors function. A number $n$ is called abundant if $\sigma(n)>2n$. Note that the natural density of the abundant numbers is about $25 \%$. The abundancy index of $n$ ...
Sebastien Palcoux's user avatar
11 votes
1 answer
241 views

Does $\chi(1)^2=|G:Z(G)|$ for irreducible character of a finite group $G$ imply $G$ is solvable?

In "Character Theory of Finite Groups" I.M. Isaacs mention the following conjecture: It is only possible in a solvable group $G$ to have $\chi(1)^2=|G:Z(G)|$ with $\chi \in$ Irr$(G)$. Is this ...
Anton B's user avatar
  • 178
2 votes
1 answer
265 views

Does the sequence (Number of groups of even order $\le n$) / (Number of groups of order $\leq n$) converge? If not, what are its cluster points?

I recently gave an undergraduate course on group theory (which is not entirely my field of expertise, so the following questions might have a well-known answer of which I am simply unaware). As I was ...
The Thin Whistler's user avatar
4 votes
0 answers
260 views

A big class of finite groups

During my researches, I've obtained a class of finite groups as follows. Let $\mathcal{C}$ be the class of all finite groups $G$ such that for every factorization $|G|=ab$ there exists a subgroup $H\...
M.H.Hooshmand's user avatar
9 votes
1 answer
321 views

Subgroups of infinite solvable groups

I'm looking for results of the form "every infinite solvable group contains <...> as a subgroup". Specifically, I believe: If $G$ is infinite solvable, finitely generated and not ...
grok's user avatar
  • 2,519
4 votes
1 answer
165 views

Centre of solvable locally nilpotent groups

This question is motivated by two examples of locally nilpotent groups which I came across (see below). Question: Given an infinite solvable and locally nilpotent group $G$, does $G$ have an infinite ...
ARG's user avatar
  • 4,432
4 votes
0 answers
200 views

Derived length in linear groups

If $G$ is a group let $(G^{(m)})_{m \geq 0}$ be the derived series. If there is some $m$ such that $G^{(m+1)} = G^{(m)}$, call the smallest such $m$ the derived length of $G$. I am interested in ...
Sean Eberhard's user avatar
9 votes
0 answers
445 views

Which finite solvable groups have solvable automorphism groups?

Is it possible to give a reasonable description of those finite solvable groups $G$ such that $A = {\rm Aut}(G)$ is also solvable? The central case to deal with is that in which $G$ is a $p$-group of ...
Geoff Robinson's user avatar
1 vote
1 answer
102 views

Infinite pro-$p$ group of finite solvable length and finite coclass

I was reading about infinite pro-$p$ groups of finite coclass from the book "The Structure of Groups of Prime Power Order" by Leedham-Green and McKay. I asked this question in math....
usermath's user avatar
  • 243
2 votes
1 answer
401 views

Questions about a finite solvable group

These questions are by Moshe Newman Let $G$ be a finite solvable group of derived length $d$, with the property that every proper subgroup and every proper quotient of $G$ has derived length less ...
David S. Newman's user avatar
3 votes
1 answer
1k views

Conditions for a solvable group to have a non-trivial center

I am working on a problem in character theory where I try to bound the derived length of a solvable group using information about its characters. In my specific case, it will be extremely helpful for ...
Joakim Færgeman's user avatar
4 votes
0 answers
124 views

Abelian-by-cyclic subgroups of exponential growth solvable groups

I am currently looking for a reference to a proof (or counterexample) to the following statement: Statement: Assume $G$ is a finitely generated solvable group of exponential growth, then there is a ...
ARG's user avatar
  • 4,432
5 votes
2 answers
377 views

Does the group G(K) have a cocompact solvable closed subgroup?

Let $K$ be a (locally compact) local field and $G$ be a linear algebraic $K$-group. Does the topological group $G(K)$ have a cocompact solvable closed subgroup? If $\mathrm{char}(K)=0$, it is true ...
m07kl's user avatar
  • 1,702
3 votes
1 answer
215 views

Commutator length in connected solvable Lie groups

Let $G$ be a connected solvable Lie group and let $H$ denote ist commutator subgroup. By definition, every element $g \in H$ can be written as a product of commutators and the minimal number of ...
Lyonel's user avatar
  • 97
3 votes
4 answers
757 views

Lucido's three prime lemma

Let G be a finite solvable group. If p,q,r are distinct primes dividing |G|, then G contains an element of order the product of two of these three primes. This is lucido's three prime lemma. I ...
Bhaskar Vashishth's user avatar
21 votes
2 answers
1k views

Is there a big solvable subgroup in every finite group?

Definition: Let $G$ be a group, and let $H \leq G$ be a subgroup. We say that $H$ is big in $G$ if for every intermediate subgroup $H \leq L \leq G$ there exists some $x \in L$ such that $\langle H \...
Pablo's user avatar
  • 11.3k
3 votes
1 answer
156 views

Bounding the derived length of a solvable group given the degrees of the irreducible monomial characters

Much is known about the derived length of a solvable group given the degrees and cardinality of the set of degrees of the irreducible characters. Martin Isaacs and Donald Passman pretty much started ...
Joakim Færgeman's user avatar
11 votes
1 answer
499 views

Are all sneaky groups products of Frobenius and 2-Frobenius groups?

I've been stuck thinking about this for a while. Def. Let $G$ be a finite solvable group whose order is divisible by only three primes: $p,q,$ and $r$. Suppose that $G$ has cyclic subgroups of ...
Alexander Gruber's user avatar
1 vote
1 answer
230 views

Portability of Thompson theorem about solvability to Moufang loops

Say we have a finite Moufang Loop $Q$, $|Q|<\infty$. There is a theorem proved by Thompson that states: Group $G$, $|G|<\infty$ is solvable $\iff$ $\forall a, b \in G \langle a, b\rangle$ is ...
Evgeny's user avatar
  • 51
4 votes
4 answers
318 views

Can group solvability be detected from identities among the generators?

For $n=1$ the answer is "yes." -- A group is abelian iff its generators commute. Let $G_0=G$ be a group and let it be generated by $X_0=X$. For each $n>0$ let $G_n=[G_{n-1},G_{n-1}]$ and let $X_n=...
Matt Brin's user avatar
  • 1,625
9 votes
1 answer
897 views

An extension of the converse to Hall's theorem.

This is an extension of this MSE question, in which I asked whether there was a counterexample to the following statement, Conjecture. If a finite group $G$ contains a $\lbrace p,q \rbrace$-Hall ...
Alexander Gruber's user avatar
5 votes
1 answer
221 views

Finite solvable groups are generated by a nilpotent subgroup + K elements?

Is there a constant $K \in \mathbb{N}$ such that for every finite solvable group $G$, there exists a nilpotent subgroup $N \leq G$, and a subset $S \subseteq G$ with $|S| \leq K$, and $\langle N,S\...
Pablo's user avatar
  • 11.3k
1 vote
0 answers
67 views

Irreducible characters of a semi-direct product with a p-group

Suppose G is a semi-direct product of P with H where P is a (non-abelian) p-group and G is solvable. I wonder what can be said about the irreducible characters of G given information about the ...
Joakim Færgeman's user avatar
4 votes
1 answer
455 views

Generators of Sylow subgroups

Is there a function $f : \mathbb{N} \rightarrow \mathbb{N}$ such that for each finite supersolvable group $G$, and a Sylow subgroup $S \leq G$ we have $d(S) \leq f(d(G))$? Here $d(H)$ denotes the ...
Pablo's user avatar
  • 11.3k
3 votes
1 answer
260 views

Schreier's formula and supersolvable groups

A finitely generated profinite group $G$ is said to satisfy Schreier's formula if for every open subgroup $L \leq_o G$ we have $d(L) = (d(G)-1)[G:L] + 1$. Here $d$ stands for the smallest cardinality ...
Pablo's user avatar
  • 11.3k
2 votes
2 answers
304 views

Number of generators of the commutator

Can one find a function $f : \mathbb{N} \rightarrow \mathbb{N}$ such that for every finite supersolvable group $G$ we have: $d(G') \leq f(d(G))$? Here $d(K)$ is the cardinality of a minimal set of ...
Pablo's user avatar
  • 11.3k
4 votes
2 answers
500 views

Is there any way to check whether a group is residually solvable?

For a given group presentation of a group(finitely presented), I want to check whether it is residually solvable or not. Is there any good way to do it? Actually, I'm curious whether the finitely ...
hopflink's user avatar
  • 537
4 votes
0 answers
177 views

Is there any probabilistic characterization for generalized solvable groups?

References: This question is inspired by a conjecture of Alon Amit that is solved by Miklós Abért, Nikolay Nikolov and Dan Segal in the following papers: (1) On the probability of satisfying a word in ...
user avatar
4 votes
2 answers
1k views

Are all connected solvable affine algebraic groups supersolvable?

The basic question is whether there is a notion of chief factor of a connected solvable algebraic group that matches my intuition. A few smaller assertions are sprinkled through the explanation, and ...
Jack Schmidt's user avatar
  • 10.7k
3 votes
1 answer
504 views

Generalization of a Result on Solvable Groups

This question concerns finite groups. It is a well-known fact that every subgroup of a solvable group must again be solvable; this is easily proven by looking at the derived series of a given ...
ARupinski's user avatar
  • 5,191