Understanding Quantum Physics Identities

kennalj65
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Hey, so today for our quantum physics class we were supposed to go through these identities, |+_x > = \frac{1}{2^{0.5}} (|+> + |->)|-_x > = \frac{1}{2^{0.5}} (|+> - |->)
|+_y > = \frac{1}{2^{0.5}} (|+> + i|->)
|-_y > = \frac{1}{2^{0.5}} (|+> - i|->)where |+ (x)> would represent spin up in the x direction for example, and |+> simply denotes spin up in (I believe) the z direction.
now I couldn't make sense of any of it, had no idea where they came from and what the proof is, I came home and googled it and noticed a strong resemblance to the pauli matrices (which I have discovered as of half an hour ago), so I'm hoping someone could enlighten me as to what this means and where it comes from.
Thanks in advance
 
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The Pauli matrices are the matrix elements of the operators
\hat{\sigma}^j=\frac{2}{\hbar} \hat{s}^j,
where \hat{s}_j are the spin components of a spin-1/2 particle.

The Pauli matrix are the matrix elements with respect to the eigenbasis of \hat{\sigma}^3,
\hat{\sigma}^3 |k \rangle=k |k \rangle, \quad k \in \{-1,1 \},
where the choice of the 3-component is conventional. The Pauli matrices are given by
{\sigma^{j}}_{kl}=\langle{k}|\hat{\sigma}^j|l\rangle, \quad k,l \in \{-1,1 \}.

You can easily calculate the Pauli matrices by making use of the raising- and lowering operators
\hat{\sigma}^{\pm} = \hat{\sigma}^{1} \pm \mathrm{i} \hat{\sigma}^{2}.
Just look in your textbook, how those operate on the basis vectors!
 
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