ORCID
http://orcid.org/0000-0002-1945-7874
Date of Award
Spring 5-15-2020
Degree Name
Doctor of Philosophy (PhD)
Degree Type
Dissertation
Abstract
In this thesis, I will discuss the relations and differences between EL-shellable and CL-shellable posets. I will present examples of EL-shellable posets that are previously known to be CL-shellable, including rank-selected subposets of EL- shellable posets such as the Smirnov words posets, and comodernistic lattices. I will show that EL-shellability is equivalent to root-independent recursive atom ordering, and present two examples of CL-shellable posets that are not EL- shellable, one of which is a graded poset and the other is ungraded. In the end, I will briefly discuss how I think might fully characterize CL-shellable posets that are not EL-shellable.
Language
English (en)
Chair and Committee
John Shareshian
Committee Members
Laura Escobar-Vega, Renato Feres, Martha Precup, Sheila Sundaram,
Recommended Citation
Li, Tiansi, "A Study on Lexicographic Shellable Posets" (2020). Arts & Sciences Electronic Theses and Dissertations. 2211.
https://openscholarship.wustl.edu/art_sci_etds/2211