Witt vectors, semirings, and total positivity

Autor: Borger, James M.
Rok vydání: 2013
Předmět:
Druh dokumentu: Working Paper
Popis: We extend the big and $p$-typical Witt vector functors from commutative rings to commutative semirings. In the case of the big Witt vectors, this is a repackaging of some standard facts about monomial and Schur positivity in the combinatorics of symmetric functions. In the $p$-typical case, it uses positivity with respect to an apparently new basis of the $p$-typical symmetric functions. We also give explicit descriptions of the big Witt vectors of the natural numbers and of the nonnegative reals, the second of which is a restatement of Edrei's theorem on totally positive power series. Finally we give some negative results on the relationship between truncated Witt vectors and $k$-Schur positivity, and we give ten open questions.
Comment: The form as it will appear in the published volume. Some minor improvements to the text, some new references
Databáze: arXiv