Please check my work on inner product operation

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SUMMARY

The discussion centers on the calculation of the norm of a vector represented in bra-ket notation, specifically |e> = (1+i, 1, i). The initial calculation incorrectly suggests that ||e|| = √(2i), neglecting the requirement for complex conjugation in the inner product. The correct approach involves computing as a real number, which requires taking the Hermitian conjugate of |e>. This correction is crucial for accurate results in linear algebra involving complex vectors.

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iScience
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i realize this is a linear algebra question, but the bra-ket notation is still a little confusing to me so i posted it in this section.


|e>=(1+i,1,i) (n-tuple representation, where i's are the imaginaries)

so the norm of this would then be the following?

||e||=$$\sqrt{<e|e>}$$=$$\sqrt{(1+i,1,i)\cdot(1+i,1,i)}$$=$$\sqrt{(1+2i+i^2)+1+i^2}$$=$$\sqrt{2i}$$
 
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iScience said:
i realize this is a linear algebra question, but the bra-ket notation is still a little confusing to me so i posted it in this section.


|e>=(1+i,1,i) (n-tuple representation, where i's are the imaginaries)

so the norm of this would then be the following?

||e||=$$\sqrt{<e|e>}$$=$$\sqrt{(1+i,1,i)\cdot(1+i,1,i)}$$=$$\sqrt{(1+2i+i^2)+1+i^2}$$=$$\sqrt{2i}$$

No, it's not right. If |e>=(1+i,1,i) then <e| is the hermitian conjugate vector. You forgot the complex conjugation. <e|e> should be a real number.
 

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