Abstract



It is well known that a bounded Hessenberg matrix with positive subdiagonal defines a subnormal operator and there exits a measure as the solution of the associated moment problem. In a recent work, the authors introduced a method to obtain the Hessenberg matrix of a sum of measures from the Hessenberg matrix of the component measures. In this work we extend this results to bounded Hessenberg matrices that represent not subnormal operators. We will denote this operation a msum and we give its expression in terms of the Cholesky factorization of the corresponding hermitian positive definite matrices associated to the Hessenberg components. Finally, we give some examples to compute the msum introduced in this paper obtaining the exact value of the finite sections of the Hessenberg matrix.  
International

Si 
Congress

10th International Symposium on Orthogonal Polynomials, Special Functions and Applications (OPSFA 2010) 

960 
Place

Leuven (Belgica) 
Reviewers

Si 
ISBN/ISSN

1111111111 


Start Date

20/07/2009 
End Date

25/07/2009 
From page

40 
To page

40 

Orthogonal Polynomials, Special Functions and Applications 