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تسجيل مستخدم جديدOn localized and coherent states on some new fuzzy spheres
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We construct various systems of coherent states (SCS) on the $O(D)$-equivariant fuzzy spheres $S^d_Lambda$ ($d=1,2$, $D=d!+!1$) constructed in [G. Fiore, F. Pisacane, J. Geom. Phys. 132 (2018), 423-451] and study their localizations in configuration space as well as angular momentum space. These localizations are best expressed through the $O(D)$-invariant square space and angular momentum uncertainties $(Deltaboldsymbol{x})^2,(Deltaboldsymbol{L})^2$ in the ambient Euclidean space $mathbb{R}^D$. We also determine general bounds (e.g. uncertainty relations from commutation relations) for $(Deltaboldsymbol{x})^2,(Deltaboldsymbol{L})^2$, and partly investigate which SCS may saturate these bounds. In particular, we determine $O(D)$-equivariant systems of optimally localized coherent states, which are the closest quantum states to the classical states (i.e. points) of $S^d$. We compare the results with their analogs on commutative $S^d$. We also show that on $S^2_Lambda$ our optimally localized states are better localized than those on the Madore-Hoppe fuzzy sphere with the same cutoff $Lambda$.
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