Hello(adsbygoogle = window.adsbygoogle || []).push({});

I'd like to know how to prove that the trace of A.A* is positive.

I don't really know how to handle the imaginary part of it. If A has any complex number in it, is it possible to get traces like 10-2i? If yes, do I consider it as a positive number or negative?:zzz:

Thanks in advance

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# How to prove trace(A.A*) is positive

**Physics Forums | Science Articles, Homework Help, Discussion**