Dyade Dirac Notation: Why Last Equation?

LagrangeEuler
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\{\vec{A},\vec{B}\}\cdot \vec{C}=\vec{A}(\vec{B}\cdot \vec{C})
\vec{C} \cdot \{\vec{A},\vec{B}\}=(\vec{C}\cdot \vec{A}) \vec{B}

I want to write dyade in Dirac notation.

(|\vec{A}\rangle\langle\vec{B}|)|\vec{C}\rangle= |\vec{A}\rangle\langle\vec{B}|\vec{C}\rangle
\langle\vec{C}|(|\vec{A}\rangle\langle\vec{B}|)=< \vec{C} |\vec{A}\rangle|\vec{B}\rangle

Why not

\langle \vec{C} |\vec{A}\rangle\langle \vec{B}|

in last equation?
 
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It should be, it should have the same 'bra-keting' as the C in the LHS.
 
I'm confused. In QM |\psi \rangle and \langle \psi | are vectors from some vector space and his dual respectively. But in some tensor analyses I don't see difference between |\vec{A}\rangle and \langle \vec{A}|.
In this case precisely. I have some number \langle|\rangle which multiply vector.
 
LagrangeEuler said:
I'm confused. In QM |\psi \rangle and \langle \psi | are vectors from some vector space and his dual respectively. But in some tensor analyses I don't see difference between |\vec{A}\rangle and \langle \vec{A}|.
In this case precisely. I have some number \langle|\rangle which multiply vector.
I don't follow what you're saying here. Yes, ##\langle C|A\rangle## is a number. Why is that a problem?

There's no need to use the arrow notation for vectors here (unless what you have in mind is that ##\vec A## is a vector in some other vector space ##\mathbb R^3##), since kets are always vectors.
 
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