All Questions
5
questions
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53
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Ising configuration after rotation in one sub-lattice
I do not understand Eq. (5.9) in Auerbach's book Interacting electrons an quantum magnetism. Consider the general spin-$S$ Heisenberg model on a bipartite lattice with $N$ sites:
$$
H = \frac{1}{2} \...
- 660
0
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0
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121
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Is it possible to construct an operator for $z$-component of spin for a 2D system?
Let's say we have an arrangement of spins in 2D space (as given in the below picture).
Assume that the $z$-axis is out of the plane and a spin (circled in red) makes an angle $\theta$ with the $x$-...
- 1,335
2
votes
1
answer
307
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Describing a subspace of a Hilbert space of $N$ spins 1/2
Consider having $N$ spins $1/2$, so the overall state of $N$ particles can be described by the total spin value $S=0 \ldots N/2$ (let us set $N$ to be even for simplicity), and the projection of the ...
- 133
0
votes
1
answer
61
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Indistinguishability in Spin-1/2-system
In terms of statistical physics I thought the microcanonical partition function can be interpreted as summing over all possible quantum numbers. Neglecting indistinguishability in the case of two ...
- 71
4
votes
1
answer
201
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Clebsch-Gordan coefficients, spin networks and intertwiners
After spending some time with LQG books and articles i have still some problems regarding concepts of this theory.
Spin network is built from lines labeled by spin label $j$ and since angular momentum ...
