Skip to main content
edited tags
Link
Todd Trimble
  • 53.3k
  • 6
  • 205
  • 322
removed tag, fixed typos
Source Link
YCor
  • 63.9k
  • 5
  • 187
  • 286

A finite 2 group-group containing the dihedral group of order 16?

A question for finite 2-group junkies ...

The dihedral group $D_{16}$ of order 16 has a presentation $D_{16}= \langle a,t \ | \ a^2=t^8=atat=e\rangle$.

Question: Does there exist a finite 2-group $G$ containing $D_{16}$ as a subgroup, and an element $g \in G$ such that $gag^{-1}=t^4$? Bonus pats-on-the-back if $G$ has order 64.

An obvious reduction: one can assume that $G =\langle D_{16},g\rangle$.

An obvious constraint: $D_{16}$ cannot be normal in $G$ (so $G$ can't have order 32).

[This question has come up in investigations of the Balmer spectrum of $G$--equivariant stable homotopy for finite $p$--groups $G$. LikeLike Dr. Frankenstein, I am looking for interesting subjects to experiment on, and my student Chris Lloyd is serving as the able assistant to the mad scientist.]

A finite 2 group containing the dihedral group of order 16?

A question for finite 2-group junkies ...

The dihedral group $D_{16}$ of order 16 has a presentation $D_{16}= \langle a,t \ | \ a^2=t^8=atat=e\rangle$.

Question: Does there exist a finite 2-group $G$ containing $D_{16}$ as a subgroup, and an element $g \in G$ such that $gag^{-1}=t^4$? Bonus pats-on-the-back if $G$ has order 64.

An obvious reduction: one can assume that $G =\langle D_{16},g\rangle$.

An obvious constraint: $D_{16}$ cannot be normal in $G$ (so $G$ can't have order 32).

[This question has come up in investigations of the Balmer spectrum of $G$--equivariant stable homotopy for finite $p$--groups $G$. Like Dr. Frankenstein, I am looking for interesting subjects to experiment on, and my student Chris Lloyd is serving as the able assistant to the mad scientist.]

A finite 2-group containing the dihedral group of order 16?

The dihedral group $D_{16}$ of order 16 has a presentation $D_{16}= \langle a,t \ | \ a^2=t^8=atat=e\rangle$.

Question: Does there exist a finite 2-group $G$ containing $D_{16}$ as a subgroup, and an element $g \in G$ such that $gag^{-1}=t^4$? Bonus pats-on-the-back if $G$ has order 64.

An obvious reduction: one can assume that $G =\langle D_{16},g\rangle$.

An obvious constraint: $D_{16}$ cannot be normal in $G$ (so $G$ can't have order 32).

[This question has come up in investigations of the Balmer spectrum of $G$-equivariant stable homotopy for finite $p$-groups $G$. Like Dr. Frankenstein, I am looking for interesting subjects to experiment on, and my student Chris Lloyd is serving as the able assistant to the mad scientist.]

Became Hot Network Question
Source Link
Nicholas Kuhn
  • 11.1k
  • 31
  • 58
Loading