Symmetric Chain Decompositions of Quotients by Wreath Products

  • Dwight Duffus
  • Kyle Thayer


Subgroups of the symmetric group $S_n$ act on $C^n$ (the $n$-fold product $C \times \cdots \times C$ of a chain $C$) by permuting coordinates, and induce automorphisms of the power $C^n$. For certain families of subgroups of $S_n$, the quotients defined by these groups can be shown to have symmetric chain decompositions (SCDs). These SCDs allow us to enlarge the collection of subgroups $G$ of $S_n$ for which the quotient $\mathbf{2}^n/G$ on the Boolean lattice $\mathbf{2}^n$ is a symmetric chain order (SCO). The methods are also used to provide an elementary proof that quotients of powers of SCOs by cyclic groups are SCOs.

Author Biographies

Dwight Duffus, Emory University
Mathematics and Computer Science
Kyle Thayer, The University of Washington
Computer Science and Engineering
Article Number