User Benjamin Steinberg

13 votes

What are some examples of ingenious, unexpected constructions?

answered Mar 11, 2012 at 3:09

13 votes

Counterexamples in universal algebra

answered Jan 9, 2014 at 3:21

13 votes

Counterexamples in universal algebra

answered Jan 9, 2014 at 3:24

13 votes

Accepted

Is there an infinite group with exactly two conjugacy classes?

answered Nov 3, 2013 at 14:01

13 votes

Counterexamples in universal algebra

answered Jan 9, 2014 at 3:14

13 votes

Awfully sophisticated proof for simple facts

answered Dec 30, 2012 at 4:58

13 votes

Cayley graphs of $A_n.$

answered Apr 4, 2016 at 15:38

13 votes

Irreducible representation of $S_n$: contained in tensor powers of the standard representation?

answered Jul 31, 2020 at 18:01

12 votes

Is any interesting question about a group G decidable from a presentation of G?

answered Oct 27, 2019 at 0:51

12 votes

Accepted

Why do these finite group Dedekind matrices seem to have integer spectrum when specialized to the order of group elements?

answered Aug 17 at 16:05

12 votes

Uncountable counterexamples in algebra

answered May 9, 2021 at 20:34

12 votes

Is a solvable group satisfying a semigroup law?

answered Oct 6, 2021 at 15:11

12 votes

Accepted

Is a retract of a free object free?

answered Mar 9, 2012 at 18:42

12 votes

When k[G/H] is multiplicity free G module ?

answered Aug 18, 2012 at 19:35

11 votes

Accepted

A space of ideals

answered Mar 26, 2012 at 14:09

11 votes

Mapping from a finite index subgroup onto the whole group

answered Mar 2, 2012 at 14:29

11 votes

Characterizing specific "concrete" mathematical objects by abstract general properties

answered Dec 18, 2011 at 1:04

11 votes

Accepted

Characterizing Groupoids via Quotients?

answered Sep 13, 2011 at 22:28

11 votes

Examples of seemingly elementary problems that are hard to solve?

answered Sep 18, 2011 at 2:20

11 votes

SAT and Arithmetic Geometry

answered Dec 6, 2012 at 16:19

11 votes

What sets of self-maps are the continuous self-maps under some topology?

answered Jul 8, 2013 at 19:50

11 votes

Fixed point theorems

answered Apr 27, 2013 at 3:14

11 votes

Accepted

Lie groups vs Lie monoids

answered Dec 28, 2013 at 0:09

11 votes

Accepted

"Concretely" writing down elements in a free profinite group

answered Sep 29, 2013 at 2:00

11 votes

Are all free monoids residually finite?

answered Jul 20, 2023 at 22:45

11 votes

Cohomological dimension of $G \times G$

answered Jun 22, 2017 at 10:30

11 votes

The number of commuting m-tuples is divisible by order of group: Improvements?

answered Jul 19, 2017 at 13:52

11 votes

Accepted

Non-isomorphic Heisenberg groups over rings

answered Dec 1, 2016 at 22:42

10 votes

Accepted

Terminology for a monoid $H$ s.t. $xy \in H^\times$ only if $x, y \in H^\times$

answered Feb 12, 2017 at 2:29

10 votes

Ron L. Graham’s lesser known significant contributions

answered Jul 10, 2020 at 17:51

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558 Answers

What are some examples of ingenious, unexpected constructions?

Counterexamples in universal algebra

Counterexamples in universal algebra

Is there an infinite group with exactly two conjugacy classes?

Counterexamples in universal algebra

Awfully sophisticated proof for simple facts

Cayley graphs of $A_n.$

Irreducible representation of $S_n$: contained in tensor powers of the standard representation?

Is any interesting question about a group G decidable from a presentation of G?

Why do these finite group Dedekind matrices seem to have integer spectrum when specialized to the order of group elements?

Uncountable counterexamples in algebra

Is a solvable group satisfying a semigroup law?

Is a retract of a free object free?

When k[G/H] is multiplicity free G module ?

A space of ideals

Mapping from a finite index subgroup onto the whole group

Characterizing specific "concrete" mathematical objects by abstract general properties

Characterizing Groupoids via Quotients?

Examples of seemingly elementary problems that are hard to solve?

SAT and Arithmetic Geometry

What sets of self-maps are the continuous self-maps under some topology?

Fixed point theorems

Lie groups vs Lie monoids

"Concretely" writing down elements in a free profinite group

Are all free monoids residually finite?

Cohomological dimension of $G \times G$

The number of commuting m-tuples is divisible by order of group: Improvements?

Non-isomorphic Heisenberg groups over rings

Terminology for a monoid $H$ s.t. $xy \in H^\times$ only if $x, y \in H^\times$

Ron L. Graham’s lesser known significant contributions