A characterization of Eisenstein polynomials generating extensions of degree p 2 and cyclic of degree p 3 over an unramified 𝔭 -adic field

Maurizio Monge[1]

  • [1] Instituto de Matemática da UFRJ, Av. Athos da Silveira Ramos 149, Centro de Tecnologia Bloco C Cidade Universitária Ilha do Fundão Caixa Postal 68530 21941-909 Rio de Janeiro - RJ - Brasil

Journal de Théorie des Nombres de Bordeaux (2014)

  • Volume: 26, Issue: 1, page 201-231
  • ISSN: 1246-7405

Abstract

top
Let p 2 be a prime. We derive a technique based on local class field theory and on the expansions of certain resultants allowing to recover very easily Lbekkouri’s characterization of Eisenstein polynomials generating cyclic wild extensions of degree p 2 over p , and extend it to when the base fields K is an unramified extension of p .When a polynomial satisfies a subset of such conditions the first unsatisfied condition characterizes the Galois group of the normal closure. We derive a complete classification of Eisenstein polynomials of degree p 2 whose splitting field is a p -extension, providing a full description of the Galois group and its higher ramification subgroups.The same methods are used to give a characterization of Eisenstein polynomials of degree p 3 generating a cyclic extension.In the last section, we deduce a combinatorial interpretation of monomial symmetric functions evaluated in the roots of the unity, which appear in certain expansions.

How to cite

top

Monge, Maurizio. "A characterization of Eisenstein polynomials generating extensions of degree $p^2$ and cyclic of degree $p^3$ over an unramified $\mathfrak{p}$-adic field." Journal de Théorie des Nombres de Bordeaux 26.1 (2014): 201-231. <http://eudml.org/doc/275781>.

@article{Monge2014,
abstract = {Let $p\ne 2$ be a prime. We derive a technique based on local class field theory and on the expansions of certain resultants allowing to recover very easily Lbekkouri’s characterization of Eisenstein polynomials generating cyclic wild extensions of degree $p^2$ over $\mathbb\{Q\}_p$, and extend it to when the base fields $K$ is an unramified extension of $\mathbb\{Q\}_p$.When a polynomial satisfies a subset of such conditions the first unsatisfied condition characterizes the Galois group of the normal closure. We derive a complete classification of Eisenstein polynomials of degree $p^2$ whose splitting field is a $p$-extension, providing a full description of the Galois group and its higher ramification subgroups.The same methods are used to give a characterization of Eisenstein polynomials of degree $p^3$ generating a cyclic extension.In the last section, we deduce a combinatorial interpretation of monomial symmetric functions evaluated in the roots of the unity, which appear in certain expansions.},
affiliation = {Instituto de Matemática da UFRJ, Av. Athos da Silveira Ramos 149, Centro de Tecnologia Bloco C Cidade Universitária Ilha do Fundão Caixa Postal 68530 21941-909 Rio de Janeiro - RJ - Brasil},
author = {Monge, Maurizio},
journal = {Journal de Théorie des Nombres de Bordeaux},
language = {eng},
month = {4},
number = {1},
pages = {201-231},
publisher = {Société Arithmétique de Bordeaux},
title = {A characterization of Eisenstein polynomials generating extensions of degree $p^2$ and cyclic of degree $p^3$ over an unramified $\mathfrak\{p\}$-adic field},
url = {http://eudml.org/doc/275781},
volume = {26},
year = {2014},
}

TY - JOUR
AU - Monge, Maurizio
TI - A characterization of Eisenstein polynomials generating extensions of degree $p^2$ and cyclic of degree $p^3$ over an unramified $\mathfrak{p}$-adic field
JO - Journal de Théorie des Nombres de Bordeaux
DA - 2014/4//
PB - Société Arithmétique de Bordeaux
VL - 26
IS - 1
SP - 201
EP - 231
AB - Let $p\ne 2$ be a prime. We derive a technique based on local class field theory and on the expansions of certain resultants allowing to recover very easily Lbekkouri’s characterization of Eisenstein polynomials generating cyclic wild extensions of degree $p^2$ over $\mathbb{Q}_p$, and extend it to when the base fields $K$ is an unramified extension of $\mathbb{Q}_p$.When a polynomial satisfies a subset of such conditions the first unsatisfied condition characterizes the Galois group of the normal closure. We derive a complete classification of Eisenstein polynomials of degree $p^2$ whose splitting field is a $p$-extension, providing a full description of the Galois group and its higher ramification subgroups.The same methods are used to give a characterization of Eisenstein polynomials of degree $p^3$ generating a cyclic extension.In the last section, we deduce a combinatorial interpretation of monomial symmetric functions evaluated in the roots of the unity, which appear in certain expansions.
LA - eng
UR - http://eudml.org/doc/275781
ER -

References

top
  1. L. Caputo, A classification of the extensions of degree p 2 over p whose normal closure is a p -extension. Journal de théorie des nombres de Bordeaux 19 (2007), no. 2, 337–355. Zbl1161.11034MR2394890
  2. I. B. Fesenko and S. V. Vostokov, Local fields and their extensions. American Mathematical Society, 2002. Zbl1156.11046MR1915966
  3. C. Greve and S. Pauli, Ramification polygons, splitting fields, and galois groups of eisenstein polynomials. International Journal of Number Theory 8 (2012), no. 06, 1401–1424. Zbl1286.11201MR2965757
  4. M. Krasner, Nombre des extensions d’un degré donné d’un corps 𝔭 -adique. C. R. Acad. Sc. Paris 254 (1962), 3470–3472, ibidem255 (1962), 224–226, 1682–1684, 2342–2344, 3095–3097. Zbl0117.02801
  5. A. Lbekkouri, On the construction of normal wildly ramified extensions over p , ( p 2 ). Archiv der Mathematik 93 (2009), no. 4, 331–344. Zbl1233.11123MR2558526
  6. E. Maus, On the jumps in the series of ramifications groups. Bull. Soc. math. France 25 (1971), 127–133. Zbl0245.12014MR364194
  7. H. Miki, On the ramification numbers of cyclic p-extensions over local fields. Journal für die Reine und Angewandte Mathematik 328 (1981), 99–115. Zbl0457.12005MR636198
  8. J. Montes Peral, Polígonos de newton de orden superior y aplicaciones aritméticas. Ph.D. thesis, Universitat de Barcelona, 1999. 
  9. J. Mináč and J. Swallow, Galois embedding problems with cyclic quotient of order p . Israel Journal of Mathematics 145 (2005), no. 1, 93–112. Zbl1069.12002MR2154722
  10. Ö. Ore, Newtonsche polygone in der theorie der algebraischen körper. Mathematische Annalen 99 (1928), no. 1, 84–117. Zbl54.0191.02MR1512440
  11. W. C. Waterhouse, The normal closures of certain Kummer extensions. Canad. Math. Bull 37 (1994), no. 1, 133–139. Zbl0794.12003

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.