Difference between revisions of "Lie-Kolchin theorem"
Ulf Rehmann (talk | contribs) m (moved Lie–Kolchin theorem to Lie-Kolchin theorem: ascii title) |
Ulf Rehmann (talk | contribs) m (tex encoded by computer) |
||
(One intermediate revision by the same user not shown) | |||
Line 1: | Line 1: | ||
− | A | + | <!-- |
+ | l0587101.png | ||
+ | $#A+1 = 16 n = 0 | ||
+ | $#C+1 = 16 : ~/encyclopedia/old_files/data/L058/L.0508710 Lie\ANDKolchin theorem | ||
+ | Automatically converted into TeX, above some diagnostics. | ||
+ | Please remove this comment and the {{TEX|auto}} line below, | ||
+ | if TeX found to be correct. | ||
+ | --> | ||
+ | |||
+ | {{TEX|auto}} | ||
+ | {{TEX|done}} | ||
+ | |||
+ | A solvable subgroup $ G $ | ||
+ | of the group $ \mathop{\rm GL} ( V) $( | ||
+ | where $ V $ | ||
+ | is a finite-dimensional vector space over an algebraically closed field) has a normal subgroup $ G _ {1} $ | ||
+ | of index at most $ \rho $, | ||
+ | where $ \rho $ | ||
+ | depends only on $ \mathop{\rm dim} V $, | ||
+ | such that in $ V $ | ||
+ | there is a [[Flag|flag]] $ F = \{ V _ {i} \} $ | ||
+ | that is invariant with respect to $ G _ {1} $. | ||
+ | In other words, there is a basis in $ V $ | ||
+ | in which the elements of $ G _ {1} $ | ||
+ | are written as triangular matrices. If $ G $ | ||
+ | is a connected closed subgroup of $ \mathop{\rm GL} ( V) $ | ||
+ | in the Zariski topology, then $ G _ {1} = G $; | ||
+ | in this case the Lie–Kolchin theorem is a generalization of Lie's theorem, which was proved by S. Lie for complex connected (in the Euclidean topology) solvable Lie groups (see [[Lie group, solvable|Lie group, solvable]]; [[Lie theorem|Lie theorem]]). This assertion can also be considered as a special case of Borel's fixed-point theorem (cf. [[Borel fixed-point theorem|Borel fixed-point theorem]]). | ||
The following analogue of the Lie–Kolchin theorem is true for an arbitrary field: A solvable group of matrices contains a normal subgroup of finite index whose commutator subgroup is nilpotent. | The following analogue of the Lie–Kolchin theorem is true for an arbitrary field: A solvable group of matrices contains a normal subgroup of finite index whose commutator subgroup is nilpotent. | ||
Line 6: | Line 33: | ||
====References==== | ====References==== | ||
− | <table><TR><TD valign="top">[1]</TD> <TD valign="top"> | + | <table><TR><TD valign="top">[1]</TD> <TD valign="top"> E.R. Kolchin, "Algebraic matrix groups and the Picard–Vessiot theory of homogeneous linear ordinary differential equations" ''Ann. of Math. (2)'' , '''49''' (1948) pp. 1–42</TD></TR><TR><TD valign="top">[2]</TD> <TD valign="top"> A.I. [A.I. Mal'tsev] Mal'Avcev, "On certain classes of infinite soluble groups" ''Transl. Amer. Math. Soc. (2)'' , '''2''' (1956) pp. 1–21 ''Mat. Sb.'' , '''28''' (1951) pp. 567–588</TD></TR><TR><TD valign="top">[3]</TD> <TD valign="top"> M.I. Kargapolov, J.I. [Yu.I. Merzlyakov] Merzljakov, "Fundamentals of the theory of groups" , Springer (1979) (Translated from Russian) {{MR|0551207}} {{ZBL|0549.20001}} </TD></TR></table> |
− | |||
− | |||
====Comments==== | ====Comments==== | ||
− | In Western literature the Lie–Kolchin theorem usually designates the more restricted version about connected closed subgroups of | + | In Western literature the Lie–Kolchin theorem usually designates the more restricted version about connected closed subgroups of $ \mathop{\rm GL} ( V) $. |
For the role of the Lie–Kolchin theorem in the Galois theory for ordinary linear differential equations see [[#References|[a1]]]. | For the role of the Lie–Kolchin theorem in the Galois theory for ordinary linear differential equations see [[#References|[a1]]]. | ||
====References==== | ====References==== | ||
− | <table><TR><TD valign="top">[a1]</TD> <TD valign="top"> | + | <table><TR><TD valign="top">[a1]</TD> <TD valign="top"> I. Kaplansky, "An introduction to differential algebra" , Hermann (1957) {{MR|0093654}} {{ZBL|0083.03301}} </TD></TR><TR><TD valign="top">[a2]</TD> <TD valign="top"> J.E. Humphreys, "Linear algebraic groups" , Springer (1975) pp. Sect. 35.1 {{MR|0396773}} {{ZBL|0325.20039}} </TD></TR><TR><TD valign="top">[a3]</TD> <TD valign="top"> A. Borel, "Linear algebraic groups" , Benjamin (1969) pp. 283ff {{MR|0251042}} {{ZBL|0206.49801}} {{ZBL|0186.33201}} </TD></TR></table> |
Latest revision as of 22:16, 5 June 2020
A solvable subgroup $ G $
of the group $ \mathop{\rm GL} ( V) $(
where $ V $
is a finite-dimensional vector space over an algebraically closed field) has a normal subgroup $ G _ {1} $
of index at most $ \rho $,
where $ \rho $
depends only on $ \mathop{\rm dim} V $,
such that in $ V $
there is a flag $ F = \{ V _ {i} \} $
that is invariant with respect to $ G _ {1} $.
In other words, there is a basis in $ V $
in which the elements of $ G _ {1} $
are written as triangular matrices. If $ G $
is a connected closed subgroup of $ \mathop{\rm GL} ( V) $
in the Zariski topology, then $ G _ {1} = G $;
in this case the Lie–Kolchin theorem is a generalization of Lie's theorem, which was proved by S. Lie for complex connected (in the Euclidean topology) solvable Lie groups (see Lie group, solvable; Lie theorem). This assertion can also be considered as a special case of Borel's fixed-point theorem (cf. Borel fixed-point theorem).
The following analogue of the Lie–Kolchin theorem is true for an arbitrary field: A solvable group of matrices contains a normal subgroup of finite index whose commutator subgroup is nilpotent.
The Lie–Kolchin theorem was proved by E.R. Kolchin [1] (for connected groups) and A.I. Mal'tsev [2] (in the general formulation). It is also sometimes called the Kolchin–Mal'tsev theorem.
References
[1] | E.R. Kolchin, "Algebraic matrix groups and the Picard–Vessiot theory of homogeneous linear ordinary differential equations" Ann. of Math. (2) , 49 (1948) pp. 1–42 |
[2] | A.I. [A.I. Mal'tsev] Mal'Avcev, "On certain classes of infinite soluble groups" Transl. Amer. Math. Soc. (2) , 2 (1956) pp. 1–21 Mat. Sb. , 28 (1951) pp. 567–588 |
[3] | M.I. Kargapolov, J.I. [Yu.I. Merzlyakov] Merzljakov, "Fundamentals of the theory of groups" , Springer (1979) (Translated from Russian) MR0551207 Zbl 0549.20001 |
Comments
In Western literature the Lie–Kolchin theorem usually designates the more restricted version about connected closed subgroups of $ \mathop{\rm GL} ( V) $.
For the role of the Lie–Kolchin theorem in the Galois theory for ordinary linear differential equations see [a1].
References
[a1] | I. Kaplansky, "An introduction to differential algebra" , Hermann (1957) MR0093654 Zbl 0083.03301 |
[a2] | J.E. Humphreys, "Linear algebraic groups" , Springer (1975) pp. Sect. 35.1 MR0396773 Zbl 0325.20039 |
[a3] | A. Borel, "Linear algebraic groups" , Benjamin (1969) pp. 283ff MR0251042 Zbl 0206.49801 Zbl 0186.33201 |
Lie-Kolchin theorem. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Lie-Kolchin_theorem&oldid=22741