42,026 research outputs found
A new species of Prosekia (Philosciidae, Isopoda) from an inundation forest (igapó) in the Central Amazon
Prosekia tarumae n. sp. (Philosciidae, Isopoda) from a Central Amazonian black-water inundation forest (lgapó) is described
Comment on "Wave functions for a Duffin-Kemmer-Petiau particle in a time-dependent potential"
It is shown that the paper "Wave functions for a Duffin-Kemmer-Petiau
particle in a time-dependent potential", by Merad and Bensaid [J. Math. Phys.
48, 073515 (2007)] is not correct in using inadvertently a non-Hermitian
Hamiltonian in a formalism that does require Hermitian Hamiltonians.Comment: 2 page
Corroborating the equivalence between the Duffin-Kemmer-Petiau and the Klein-Gordon and Proca equations
It is shown that the Hamiltonian version of the Duffin-Kemmer-Petiau theory
with electromagnetic coupling brings about a source term at the current. It is
also shown that such a source term disappears from the scenario if one uses the
correct physical form for the Duffin-Kemmer-Petiau field, regardless the choice
for representing the Duffin-Kemmer-Petiau matrices. This result is used to fix
the ambiguity in the electromagnetic coupling in the Duffin-Kemmer-Petiau
theory. Moreover, some widespread misconceptions about the Hermiticity in the
Duffin-Kemmer-Petiau theory are discussed.Comment: 13 pages, to appears in Phys. Rev.
On the bound-state spectrum of a nonrelativistic particle in the background of a short-ranged linear potential
The nonrelativistic problem of a particle immersed in a triangular potential
well, set forth by N.A. Rao and B.A. Kagali, is revised. It is shown that these
researchers misunderstood the full meaning of the potential and obtained a
wrong quantization condition. By exploring the space inversion symmetry, this
work presents the correct solution to this problem with potential applications
in electronics in a simple and transparent way
Missing solution in a Cornell potential
Missing bound-state solutions for fermions in the background of a Cornell
potential consisting of a mixed scalar-vector-pseudoscalar coupling is
examined. Charge-conjugation operation, degeneracy and localization are
discussed
Bound states of the Duffin-Kemmer-Petiau equation with a mixed minimal-nonminimal vector cusp potential
The problem of spin-0 and spin-1 bosons subject to a general mixing of
minimal and nonminimal vector cusp potentials is explored in a unified way in
the context of the Duffin-Kemmer-Petiau theory. Effects on the bound-state
solutions due to a short-range interaction are discussed in some detail
Science with the World Space Observatory - Ultraviolet
The World Space Observatory-Ultraviolet (WSO-UV) will provide access to the
UV range during the next decade. The instrumentation on board will allow to
carry out high resolution imaging, high sensitivity imaging, high resolution
(R~55000) spectroscopy and low resolution (R~2500) long slit spectroscopy. In
this contribution, we briefly outline some of the key science issues that
WSO-UV will address during its lifetime. Among them, of special interest are:
the study of galaxy formation and the intergalactic medium; the astronomical
engines; the Milky Way formation and evol ution, and the formation of the Solar
System and the atmospheres of extrasolar p lanets.Comment: Just one text file (aigomezdecastro.tex). To be published in the
proceeding of the conference: "New Quest in Stellar Astrophysics II: UV
properties of evolved stellar populations" held in Puerto Vallarta - Mexico,
in april 200
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