Talk:Unitary matrix

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Mathematics rating: Stub Class Mid Priority  Field: Algebra

Could the author please replace the plus sign with a dagger?

—Preceding unsigned comment added by 146.232.75.208 (talk) 16:48, 14 September 2007 (UTC)

The conjugate transpose is also known as the hermitian adjoint, represented with a dagger. For example:

U^dagger * U = I_n where the carrot represents a superscript and the underscore the subscript.

Just a thought but could someone add in an explaination of the unitary group when the field is finite? Since the definition of the unitary matrix relies on the conjugate transpose is there an equivalent definition of "conjugate transpose on a finite field"? TooMuchMath 20:20, 13 April 2006 (UTC)

"Note this condition says that a matrix U is unitary if it has an inverse which is equal to its conjugate transpose U^* \,." Would it be more precise here to use "if and only if" rather than just "if" ? Or maybe call it an alternative definition? Richard Giuly 05:22, 24 October 2006 (UTC)

[edit] Symbol conventions

This article uses dagger for conjugate transpose, but in conjugate transpose article we use star. Both articles should use the same notation convention. I personally prefer dagger. What are your preferences? Merilius 21:30, 03 March 2008 (UTC)

I prefer A^\dagger both from personal use (quantum mechanics) and for the reduced ambiguity, since * means many things in many contexts. I think, though, that as long as each article uses an internally consistent convention and explains the symbology it is not necessary to regularize them. - Eldereft ~(s)talk~ 21:20, 3 March 2008 (UTC)