Undergrad Can a Hermitian matrix have complex eigenvalues?

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A Hermitian matrix cannot have complex eigenvalues; it must have real eigenvalues. The discussed matrix, which has complex roots and elements, is classified as non-Hermitian. It is identified as a complex matrix, but without additional properties, it cannot be classified further. The determinant being the same for the matrix and its transpose is a property of all square matrices. For more detailed classification, specific symmetry properties would be needed.
SeM
Hi, I have a matrix which gives the same determinant wether it is transposed or not, however, its eigenvalues have complex roots, and there are complex numbers in the matrix elements. Can this matrix be classified as non-Hermitian?

If so, is there any other name to classify it, as it is not unitary, norm or skew-hermitian?

Thanks
 
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SeM said:
Hi, I have a matrix which gives the same determinant wether it is transposed or not, ...
All square matrices have this property, because the determinant is a symmetric polynomial in the matrix entries..
... however, its eigenvalues have complex roots, and there are complex numbers in the matrix elements. Can this matrix be classified as non-Hermitian?
Yes.
If so, is there any other name to classify it, as it is not unitary, norm or skew-hermitian?

Thanks
A complex matrix. Without any further properties known, preferably symmetry properties, it is impossible to give a more detailed answer than this, because you basically asked: How would you name a complex matrix, which is neither ...?
 
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Note that the only way you can get a Complex determinant is if you have Complex entries; manipulation of Reals leading to determinant will necessarily produce Real values, i.e., matrix with Real entries will necessarily have Real determinant, tho not necessarily Real eigenvalues nor Real n-ples of eigenvectors...
 
fresh_42 said:
All square matrices have this property, because the determinant is a symmetric polynomial in the matrix entries..

Yes.

A complex matrix. Without any further properties known, preferably symmetry properties, it is impossible to give a more detailed answer than this, because you basically asked: How would you name a complex matrix, which is neither ...?

Thanks! Very clear and concise answer.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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