What is the Adjoint of a Linear Operator?

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SUMMARY

The discussion focuses on the properties of the adjoint of a linear operator, specifically addressing the relationship between the null spaces of the operators T and T*T in finite-dimensional vector spaces. It establishes that N(T*T) is a subset of N(T), contingent on the rank of T being greater than zero. The participant also notes that if the dimension of the range of T, denoted as dim(R(T)), is zero, then the null space of T is trivially satisfied. The conversation seeks alternative methods to demonstrate these properties.

PREREQUISITES
  • Understanding of linear operators in vector spaces
  • Familiarity with null spaces and range of operators
  • Knowledge of inner product spaces and their properties
  • Basic concepts of linear algebra, particularly regarding dimensions
NEXT STEPS
  • Study the properties of adjoint operators in linear algebra
  • Learn about the implications of the Rank-Nullity Theorem
  • Explore examples of linear operators and their null spaces
  • Investigate alternative proofs for the relationship between N(T*T) and N(T)
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Students and educators in linear algebra, mathematicians exploring operator theory, and anyone interested in the properties of linear transformations and their adjoints.

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Homework Statement


T is a linear operator on a finite dimensional vector space. then N(T*T)=N(T). the null space are equal.


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The Attempt at a Solution


this is my method, but its does not work if dim(R(T))=0. I'm only concerned with showing
N(T*T) [tex]\subseteq[/tex] N(T). let x beong to N(T*T) then <T*T(x),y>=0=<T(x),T(y)> for all y in the vector space. thus, if dim(R(T)) > 0 then there exists y such that T(y) is not equal to zero so T(x)=0.

any other methods out there?
 
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okay i think i got it if dim(R(T))=0 then ofcourse x is in the null space of T.
 
But that's only true for the trivial case, the 0 matrix.
 

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