Matrix representation in QM Assignment -- Need some help please

AI Thread Summary
The discussion revolves around a quantum mechanics assignment that requires constructing matrices for spin operators Sx, Sy, and Sz using the eigenstates |x+⟩ and |x−⟩ as a new basis. The original poster seeks validation for their method and algebra in transforming the eigenstates from |z+⟩ and |z−⟩ to the new basis. They provide their calculations, showing the relationships between the eigenstates and the Sx operator. Additionally, they request guidance on how to evaluate the Sy and Sz operators. The conversation emphasizes the importance of using LaTeX for clarity in presenting mathematical work.
Ashish Somwanshi
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Homework Statement
In the lecture, we used the eigenstates |z+⟩ and |z−⟩ of Sz^, we obtained the matrices for spin operators

Sx^=ℏ/2(0,1,1,0) Sy^=ℏ/2(0,i,−i,0) Sz^=ℏ/2(1,0,0,−1)
note: the numbers in brackets are 2×2 matrices!!!


Now use the eigenstates of |x+⟩ and |x−⟩ of Sx^,as a new basis, construct matrices for the spin operators Sx^, Sy^ and Sz^.
Relevant Equations
Both Question and Relevant equations are posted below in attempt.
This screenshot contains the original assignment statement and I need help to solve it. I have also attached my attempt below. I need to know if my matrices were correct and my method and algebra to solve the problem was correct...
Screenshot_20221008_235549.jpg
 

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Ashish Somwanshi said:
Homework Statement:: In the lecture, we used the eigenstates |z+⟩ and |z−⟩ of Sz^, we obtained the matrices for spin operators

Sx^=ℏ/2(0,1,1,0) Sy^=ℏ/2(0,i,−i,0) Sz^=ℏ/2(1,0,0,−1)
note: the numbers in brackets are 2×2 matrices!Now use the eigenstates of |x+⟩ and |x−⟩ of Sx^,as a new basis, construct matrices for the spin operators Sx^, Sy^ and Sz^.
Relevant Equations:: Both Question and Relevant equations are posted below in attempt.

I have also attached my attempt below.
Please make it a habit to post your work using LaTeX, and not in blurry attached pictures. There is a "LaTeX Guide" link below the Edit window to help you learn LaTeX. Thank you.
 
My solution to above assignment goes like this:

Since
| ×±> = 1/ sqrt(2) |z+> ± 1/sqrt(2) |z->

|x+> = 1/sqrt (2) |z+> + 1/sqrt(2) |z->
|x-> = 1/sqrt(2) |z+> - 1/sqrt(2) |z->

So eigenvalue equations are:

Sx |x+> = 1/sqrt(2) { |z+> + |z->}
Sx |x-> = 1/sqrt(2) { |z+> - |z->}

So we can represent Sx operator in matrix form as:

Sx = 1/sqrt(2)*
|z+> + |z->0
0|z+> - |z->

Is my method to evaluate Sx operator from the relationship between x and z correct? Also how can I evaluate Sy and Sz operators for spin.?
 
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