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A question about linear algebra...

In this link:

http://math.rice.edu/~friedl/math355_fall04/Jordan.pdf

On page 3, what does it mean by the dimension of E? Does it mean the dimension of the null space?

Thanks in advance
Reply 1
The E-spaces are just vector spaces. It is the dimension of those vector spaces.

They are defined as the null spaces of certain linear transformations i.e.

EλkE_\lambda^k is defined (on the same page) to be the null space of the linear transformation (AλI)k(A-\lambda I)^k.

So for example, Eλ1E_\lambda^1 is the null space of (AλI)(A-\lambda I) i.e. the eigenspace for λ\lambda.
(edited 11 years ago)
Reply 2
Original post by Mark85
The E-spaces are just vector spaces. It is the dimension of those vector spaces.

They are defined as the null spaces of certain linear transformations i.e.

EλkE_\lambda^k is defined (on the same page) to be the null space of the linear transformation (AλI)k(A-\lambda I)^k.

So for example, EλkE_\lambda^k is the null space of (AλI)(A-\lambda I) i.e. the eigenspace for λ\lambda.


So that's just the number of free varaibles right?
Reply 3
Original post by Artus
So that's just the number of free varaibles right?


It depends what you mean by "the number of free variables".

If you mean the number of zero-rows in the reduced echelon form of the matrix (AλI)k(A-\lambda I)^k, then yes - that is one way to calculate the nullity i.e. the dimension of the nullspace of (AλI)k(A-\lambda I)^k.
Reply 4
Original post by Mark85
It depends what you mean by "the number of free variables".

If you mean the number of zero-rows in the reduced echelon form of the matrix (AλI)k(A-\lambda I)^k, then yes - that is one way to calculate the nullity i.e. the dimension of the nullspace of (AλI)k(A-\lambda I)^k.


By "the number of free variables" I mean the number of columns that do not have a pivot...so I'm gussing that that's equal to the number of zero rows...
(edited 11 years ago)
Reply 5
Original post by Artus
By "the number of free variables" I mean the number of columns that do not have a pivot...so I'm gussing that that's equal to the number of zero rows...


Yes. You are using method specific language and terminology which is more varied whereas I was trying to talk about what it is you are actually trying to calculate which has more standard and less varied terminology.

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