Can I bra through a Modulus in Quantum Mechanics?

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SUMMARY

The discussion centers on the application of bra-ket notation in quantum mechanics, specifically regarding the modulus of the sum of two ket vectors, ||V> + |W>. The user kq6up inquires whether it is valid to express the inner product + |W>| as | + |. The consensus is that one cannot take an inner product between a vector and a scalar, indicating that the proposed manipulation is incorrect. Understanding the basis and coefficients of the vectors involved is essential for proper application of these concepts.

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If I have something like ||V>+|W>| That is the modulus of sum of two ket vectors, can I "bra" through the modulus like: <V|(||V>+|W>| )=|<V|V>+<V|W>|?

Thanks,
kq6up
 
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kq6up said:
||V>+|W>|
I have never heard of the modulus of a vector without knowing anything about the basis being used - at least you need to know the coefficients corresponding to each basis vector.
kq6up said:
can I "bra" through the modulus like: <V|(||V>+|W>| )=|<V|V>+<V|W>|?
You cannot take an inner product between a vector and a scalar.
 
When you put it as you did in your second line, it makes sense that my approach was wrong headed.

Thanks,
kq6up
 

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