Calculate the eigenfunctions for a spin half particle

borndisaster
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Homework Statement


Spin can be represented by matrices. For example, a spin half particle can be described by the following Pauli spin matrices
s_x = \frac{\hbar} {2} \begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix} , s_y = \frac{\hbar} {2} \begin{pmatrix} 0 & -i \\ i & 0 \end{pmatrix} , s_z = \frac{\hbar} {2} \begin{pmatrix} 1 & 0 \\ 0 & -1 \end{pmatrix}

Calculate the corresponding eigenfunctions which we will denote as ɑ- and β-eigenfunctions corresponding to spin 1/2 particles. Further show that sj can be determined by the commutation of the other two matrices sn and sm , n,m≠j.

Homework Equations

The Attempt at a Solution


I have calculated the eigenvalues (first section of the question) of all three matrices to be ±ħ/2

I think the diagonal matrix sz has eigenfunctions |α> = (1; 0) and |β> = (0; 1)
From that I found the eigenfunctions of sx and sx to be
|x+> = |α> + |β> & |x-> = -|α> + |β> and
|y+> = -i|α> + |β> & |y-> = i|α> + |β> respectively

But I'm not entirely sure I'm correct...
 
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borndisaster said:
From that I found the eigenfunctions of sx and sx to be
|x+> = |α> + |β> & |x-> = -|α> + |β> and
|y+> = -i|α> + |β> & |y-> = i|α> + |β> respectively
Apart from normalization, these are correct.
 
Thanks @DrClaude

Any ideas as to how I show the commutation part of the question?
 
borndisaster said:
Any ideas as to how I show the commutation part of the question?
Calculate the commutator for each pair of operators and see what you get.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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