Product of three positive semi-definite matrices
نویسنده
چکیده
In [2], the author showed that a square matrix with nonnegative determinant can always be written as the product of five or fewer positive semi-definite matrices. This is an extension to the result in [1] asserting that every matrix with positive determinant is the product of five or fewer positive definite matrices. Analogous to the analysis in [1], the author of [2] studied those matrices which can be expressed as the product of two, three, or four positive semi-definite matrices. In particular, characterizations were obtained for the matrices that can be expressed as the product of two or four positive semi-definite matrices. For the remaining case, it was shown in [2] that for a complex square matrix T = [
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