The basis monomial ring of a matroid
β Scribed by Neil L White
- Publisher
- Elsevier Science
- Year
- 1977
- Tongue
- English
- Weight
- 331 KB
- Volume
- 24
- Category
- Article
- ISSN
- 0001-8708
No coin nor oath required. For personal study only.
β¦ Synopsis
We define the basis monomial ring M, of a matroid G and prove that it is Cohen-Macaulay for finite G. We then compute the Krull dimension of M, , which is the rank over Q of the basis-point incidence matrix of G, and prove that dim B, > dim M, under a certain hypothesis on coordinatizability of G, where Bo is the bracket ring of G.
π SIMILAR VOLUMES
We consider the problem of characterizing the sets of externally and internally active elements in a matroid. The main result is a canonical decomposition of the set of elements of a matroid on a linearly ordered set into external and internal elements with respect to a given basis.
We introduce the concept of depth and r-depth of a matroid M, proving that the sequence of the r-depths is the conjugate partition of the rank partition of M. The notion of quasitransversal is defined and its properties stated. We also present connections between the concept of r-depth, the quasi-tr