two psd matrices is psd if and only if the product is normal.
On the range of a Hadamard power of a positive semidefinite matrix
โ Scribed by Xiaosong Sun; Xiankun Du; Dayan Liu
- Publisher
- Elsevier Science
- Year
- 2006
- Tongue
- English
- Weight
- 88 KB
- Volume
- 416
- Category
- Article
- ISSN
- 0024-3795
No coin nor oath required. For personal study only.
โฆ Synopsis
For any n ร n complex matrix A and any integer k 1, we prove that the span of image of the map x โ (Ax) (k) is equal to the range of (AA * ) (k) , where X * and X (k) denote the conjugate transpose and the kth Hadamard power of a matrix X, respectively. This settles a conjecture, due to Gorni and Tutaj-Gasiลska, related to the study of the Jacobian Conjecture.
๐ SIMILAR VOLUMES
Let a(n) be the gre&est possible sum of the entries of a Hadamard matrix of order n. We derive n na 2-m 0 tn < a(n) f wh which implies Besides, u(n) is evaluated for n < 24 and several other values of n. 1.