Matrices That Commute with Their Conjugate and Transpose ()
Abstract
It is known that if A∈Mn is normal (AA*=A*A) , then AA￣=A￣A if and only if AAT=ATA. This leads to the question: do both AA￣=A￣A and AAT=ATA imply that A is normal? We give an
example to show that this is false when n=4, but we show that it is true when n=2 and n=3.
Share and Cite:
G. Goodson, "Matrices That Commute with Their Conjugate and Transpose,"
Advances in Linear Algebra & Matrix Theory, Vol. 3 No. 3, 2013, pp. 22-25. doi:
10.4236/alamt.2013.33005.
Conflicts of Interest
The authors declare no conflicts of interest.
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