... | ... | @@ -69,8 +69,8 @@ can define this in the following way. We take all the sites that are in the |
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fundamental domain of the symmetry group, or connected by a hopping to such
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sites; call this set `S`. We now define the *connection set*, `C`, as the set
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of symmetry group elements that map sites from the fundamental domain to sites
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in `S`. Note that the connection set always contains the identity (for a finite
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system or a completely disconnected infinite system).
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in `S`. Note that the connection set always contains the identity (and only
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this element for a finite system or a completely disconnected infinite system).
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Take the example of a 1D chain with nearest-neighbor hoppings, the connection
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set is `{(0,), (1,), (-1,)}`. With second-nearest neighbor hoppings in addition
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