English

On the ranks and implicit constant fields of valuations induced by pseudo monotone sequences

Algebraic Geometry 2021-08-04 v2 Commutative Algebra

Abstract

Given a valued field (K,v)(K,v) and a pseudo monotone sequence EE in (K,v)(K,v), one has an induced valuation vEv_E extending vv to K(X)K(X). After fixing an extension of vEv_E to a fixed algebraic closure K(X)\overline{K(X)} of K(X)K(X), we show that the implicit constant field of the extension (K(X)K,vE)(K(X)|K,v_E) is simply the henselization of (K,v)(K,v). We consider the question: given a value transcendental extension ww of vv to K(X)K(X) and a pseudo monotone sequence EE in (K,v)(K,v), under which precise conditions is ww induced by EE? The dual nature of pseudo convergent sequences of algebraic type and pseudo divergent sequences is also explored. Further, we provide a complete description of the various possibilities of the rank of the valuation vEv_E, provided that vv has finite rank.

Keywords

Cite

@article{arxiv.2107.10570,
  title  = {On the ranks and implicit constant fields of valuations induced by pseudo monotone sequences},
  author = {Arpan Dutta},
  journal= {arXiv preprint arXiv:2107.10570},
  year   = {2021}
}

Comments

New version. Introduction and Section 9 have been modified. 24 pages, 4 figures