Cohomology of integer matrices and local-global divisibility on the torus

Marco Illengo[1]

  • [1] Scuola Normale Superiore Piazza dei Cavalieri 7 56126 Pisa, Italia

Journal de Théorie des Nombres de Bordeaux (2008)

  • Volume: 20, Issue: 2, page 327-334
  • ISSN: 1246-7405

Abstract

top
Let p 2 be a prime and let  G be a p -group of matrices in SL n ( ) , for some integer  n . In this paper we show that, when n < 3 ( p - 1 ) , a certain subgroup of the cohomology group H 1 ( G , 𝔽 p n ) is trivial. We also show that this statement can be false when n 3 ( p - 1 ) . Together with a result of Dvornicich and Zannier (see [2]), we obtain that any algebraic torus of dimension n < 3 ( p - 1 ) enjoys a local-global principle on divisibility by  p .

How to cite

top

Illengo, Marco. "Cohomology of integer matrices and local-global divisibility on the torus." Journal de Théorie des Nombres de Bordeaux 20.2 (2008): 327-334. <http://eudml.org/doc/10838>.

@article{Illengo2008,
abstract = {Let $\{p\ne 2\}$ be a prime and let $G$ be a $p$-group of matrices in $\{\{\{\mathrm\{SL\}\}\}_n(\mathbb\{Z\})\}$, for some integer $n$. In this paper we show that, when $\{n&lt;3(p-1)\}$, a certain subgroup of the cohomology group $\{H^1(G,\{\{\mathbb\{F\}\}\}_p^n)\}$ is trivial. We also show that this statement can be false when $\{n\ge 3(p-1)\}$. Together with a result of Dvornicich and Zannier (see [2]), we obtain that any algebraic torus of dimension $\{n&lt;3(p-1)\}$ enjoys a local-global principle on divisibility by $p$.},
affiliation = {Scuola Normale Superiore Piazza dei Cavalieri 7 56126 Pisa, Italia},
author = {Illengo, Marco},
journal = {Journal de Théorie des Nombres de Bordeaux},
keywords = {cohomology of groups; algebraic tori; local-global divisibility},
language = {eng},
number = {2},
pages = {327-334},
publisher = {Université Bordeaux 1},
title = {Cohomology of integer matrices and local-global divisibility on the torus},
url = {http://eudml.org/doc/10838},
volume = {20},
year = {2008},
}

TY - JOUR
AU - Illengo, Marco
TI - Cohomology of integer matrices and local-global divisibility on the torus
JO - Journal de Théorie des Nombres de Bordeaux
PY - 2008
PB - Université Bordeaux 1
VL - 20
IS - 2
SP - 327
EP - 334
AB - Let ${p\ne 2}$ be a prime and let $G$ be a $p$-group of matrices in ${{{\mathrm{SL}}}_n(\mathbb{Z})}$, for some integer $n$. In this paper we show that, when ${n&lt;3(p-1)}$, a certain subgroup of the cohomology group ${H^1(G,{{\mathbb{F}}}_p^n)}$ is trivial. We also show that this statement can be false when ${n\ge 3(p-1)}$. Together with a result of Dvornicich and Zannier (see [2]), we obtain that any algebraic torus of dimension ${n&lt;3(p-1)}$ enjoys a local-global principle on divisibility by $p$.
LA - eng
KW - cohomology of groups; algebraic tori; local-global divisibility
UR - http://eudml.org/doc/10838
ER -

References

top
  1. J. W. S. Cassels, An introduction to the Geometry of Numbers. Springer, 1997. Zbl0866.11041MR1434478
  2. R. Dvornicich, U. Zannier, Local-global divisibility of rational points in some commutative algebraic groups. Bull. Soc. Math. France 129 (2001), no. 3, 317–338. Zbl0987.14016MR1881198
  3. R. Dvornicich, U. Zannier, On a local-global principle for the divisibility of a rational point by a positive integer. Bull. London Math. Soc. 39 (2007), 27–34. Zbl1115.14011MR2303515
  4. J.-P. Serre, Représentations linéaires des groupes finis. Hermann, 1967. Zbl0189.02603MR232867

NotesEmbed ?

top

You must be logged in to post comments.