Question on spin 1/2 states in arbitrary direction

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SUMMARY

The discussion centers on solving a problem related to spin 1/2 states in arbitrary directions, specifically finding the coefficients gamma and beta. The user initially struggles with the calculations involving the states |n;+> and |n;->, which are expressed in terms of angles theta and phi. The resolution involves normalizing the state |ψ⟩ and factoring out a phase, leading to a correct solution. The key takeaway is the importance of normalization and proper handling of phase factors in quantum state calculations.

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Shivy G
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Homework Statement



upload_2016-2-29_18-55-54.png


The problem is given above. I am struggling on the first two parts, where I am tasked with finding gamma and beta.

Homework Equations



For spin one half states in arbitrary directions, I know that psi = a*|n;+> + b*|n;-> .

|n;+> = cos(theta/2)|+> +sin(theta/2)*ei*phi|->

|n;-> = -sin(theta/2)e-i*phi|+> + cos(theta/2)|->

The Attempt at a Solution



I have attached my attempt at a solution. I am not sure what I am doing wrong at this point. Any help for the problem would be greatly appreciated :)
 

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There are multiple mistakes in your calculation. I would suggest that you start over again from the first step by first normalizing the given ##|\psi\rangle##.
 
I ended up getting the solution. I was making a mistake by splitting it up into |n;+> and |n;->. Instead, I factored out a phase and then normalized the whole thing. The answer came fairly quickly from there. Thanks.
 

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