Recently, Kayumov [Lobachevskii J. Math. 38 (2017), pp. 466–468] obtained a sharp estimate for the n n -th truncated area functional normalize...

When we deal with H∞, it is known that c0−interpolating sequences are interpolating and sufficient to interpolate idempotents of ℓ∞ in order the whole ℓ∞. We will extend these results frame for Bloch type spaces Bv∞ study connection between operators on Bv0. Furthermore, some particular weights v, provide examples whose constant separation as close 0 desired.

Motivated by a recent proposal on the possibility of observing a monopole in the band structure, and by an increasing interest on the role of Berry phase in spintronics, we studied the adiabatic motion of a wave packet of Bloch functions, under a perturbation varying slowly and incommensurately to the lattice structure. We show, using only the fundamental principles of quantum mechanics, that t...

We discuss a generalization to 2 qubits of the standard Bloch sphere representation for a single qubit, in the framework of Hopf fibrations of high dimensional spheres by lower dimensional spheres. The single qubit Hilbert space is the 3-dimensional sphere S. The S base space of a suitably oriented S Hopf fibration is nothing but the Bloch sphere, while the circular fibres represent the qubit o...