The observable G, is however, somewhat misleading, since a signiﬁcant part of the ﬂuctuations δE0 from one realization of the ensemble to another arises simply from the ﬂuctuation of the centroid and width of the overall spectral envelope, TrH and TrH 2 .
Spin Structure of Many-Body Systems with Two-Body Random Interactions
The centroid and width for a given system are almost identical in sectors of different total many-body spin.
Spin Structure of Many-Body Systems with Two-Body Random Interactions
N >> m >> 2, the normalized state density ρ(E ) = hδ(H − E )i takes Gaussian form and it is deﬁned by its centroid ǫ = hH i and variance σ2 = h(H − ǫ)2 i.
Structure of wavefunctions in (1+2)-body random matrix ensembles
H − ǫH )2i h(Hk − ǫH )2i Note that the centroids of the E and Ek energies are both given by ǫH = hH i.
Structure of wavefunctions in (1+2)-body random matrix ensembles
The h(1) + V generates the Fk (E ) centroids Ek .
Structure of wavefunctions in (1+2)-body random matrix ensembles
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