26,754 research outputs found
Hadronic B Decays to Charmless VT Final States
Charmless hadronic decays of B mesons to a vector meson (V) and a tensor
meson (T) are analyzed in the frameworks of both flavor SU(3) symmetry and
generalized factorization. We also make comments on B decays to two tensor
mesons in the final states. Certain ways to test validity of the generalized
factorization are proposed, using decays. We calculate the branching
ratios and CP asymmetries using the full effective Hamiltonian including all
the penguin operators and the form factors obtained in the non-relativistic
quark model of Isgur, Scora, Grinstein and Wise.Comment: 27 pages, no figures, LaTe
Observable estimation of entanglement of formation and quantum discord for bipartite mixed quantum states
We present observable lower and upper bounds for the entanglement of
formation (EOF) and quantum discord (QD), which facilitates estimates of EOF
and QD for arbitrary experimental unknown states in finite-dimensional
bipartite systems. These bounds can be easily obtained by a few experimental
measurements on a twofold copy of the mixed states.
Based on our results, we use the experimental measurement data of the real
experiment given by Schmid \textit{et al.} [Phys. Rev. Lett. \textbf{101},
260505 (2008)] to obtain the lower and upper bounds of EOF and QD for the
experimental unknown state.Comment: 8 pages, 5 figure
Incompressible strips in dissipative Hall bars as origin of quantized Hall plateaus
We study the current and charge distribution in a two dimensional electron
system, under the conditions of the integer quantized Hall effect, on the basis
of a quasi-local transport model, that includes non-linear screening effects on
the conductivity via the self-consistently calculated density profile. The
existence of ``incompressible strips'' with integer Landau level filling factor
is investigated within a Hartree-type approximation, and non-local effects on
the conductivity along those strips are simulated by a suitable averaging
procedure. This allows us to calculate the Hall and the longitudinal resistance
as continuous functions of the magnetic field B, with plateaus of finite widths
and the well-known, exactly quantized values. We emphasize the close relation
between these plateaus and the existence of incompressible strips, and we show
that for B values within these plateaus the potential variation across the Hall
bar is very different from that for B values between adjacent plateaus, in
agreement with recent experiments.Comment: 13 pages, 11 figures, All color onlin
Sustainable farming with native rocks: the transition without revolution.
The development process which humanity passed through favored a series of conquests, reflected in the better quality of life and longevity, however, it also provoked upsets and severe transformation in the environment and in the human food security. Such process is driving the ecosystems to be homogeneous, and, therefore,the nutrients� supply, via nourishment. To change this panorama, the present work discusses the gains of incorporating the stonemeal technique as a strategic alternative to give back the essential fertile characteristics to the soils. This technology has the function of facilitating the rejuvenation of the soils and increasing the availability of the necessary nutrients to the full development of the plants which is a basic input for the proliferation of life in all its dimensions
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