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Viewing Version 2 of 'Jordan canonical form theorem'
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Title of object: Jordan canonical form theorem
Canonical Name: JordanCanonicalFormTheorem
Type: Theorem

Created on: 2002-08-26 10:37:19.385473-04
Modified on: 2002-08-26 15:50:57.121592-04

Creator: vypertd
Modifier: vypertd
Author: vypertd

Classification: msc:15A18
Defines: Jordan block, Jordan matrix

Revision comment (for changes between this and next version):

Changes for correction #1022 ('title/synonym').

Preamble:

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Content:

Let $V$ be a finite-dimensional vector space over a field $F$ and $t:V \to V$ be a linear transformation. Then, if the characteristic polynomial factorizes completely over F, there will exist a basis of $V$ with respect to which the matrix of $t$ is of the form
$$\begin{pmatrix}
J_{1} & 0 & ... & 0\\
0 & J_{2} & ... & 0\\
& & ... & \\
0 & 0 & ... & J_{k}
\end{pmatrix}$$
where each $J_{i}$ is a reduced (Jordan) matrix in which $\lambda = \lambda_{i}$.
A \textbf{Jordan block} or Jordan matrix is a matrix of the form
$$\begin{pmatrix}
\lambda & 1 & 0 & ... & 0\\
0 & \lambda & 1 & ... & 0\\
0 & 0 & \lambda & ... & 0\\
\vdots & \vdots & \vdots & \ddots & 1\\
0 & 0 & 0 & ... & \lambda
\end{pmatrix}$$
with a constant value $\lambda$ along the diagonal and 1's on the superdiagonal. Some texts place the 1's on the subdiagonal instead.