Is there a guide to using the density matrix formalism in quantum mechanics?

peterjaybee
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Hello, I am looking for a guide to quantum mechanics and the density matrix formalism which uses the Einstein summation convention. Does such a guide exist?
 
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I ask because bra's and ket's seem to behave in a similar manner to co-varient and contra-varient vectors. I guess this is not a coincidence.
 
peterjaybee said:
I ask because bra's and ket's seem to behave in a similar manner to co-varient and contra-varient vectors. I guess this is not a coincidence.

No. See the section ''What are bras and kets'' in Chapter A1 of my theoretical physics FAQ at
http://arnold-neumaier.at/physfaq/physics-faq.html#A1
 

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