8,893 research outputs found
On -norm preservers and the Aleksandrov conservative -distance problem
The goal of this paper is to point out that the results obtained in the
recent papers [7,8,10,11] can be seriously strengthened in the sense that we
can significantly relax the assumptions of the main results so that we still
get the same conclusions. In order to do this first, we prove that for any transformation which preserves the -norm of any vectors is
automatically plus-minus linear. This will give a re-proof of the well-known
Mazur--Ulam-type result that every -isometry is automatically affine () which was proven in several papers, e.g. in [9]. Second, following the
work of Rassias and \v{S}emrl [23], we provide the solution of a natural
Aleksandrov-type problem in -normed spaces, namely, we show that every
surjective transformation which preserves the unit -distance in both
directions () is automatically an -isometry
The phase diagram in the vector meson extended linear sigma model
We investigate the chiral phase transition of the strongly interacting matter
at nonzero temperature and baryon chemical potential within an extended
(2+1) flavor Polyakov constituent quark-meson model which incorporates the
effect of the vector and axial vector mesons. The parameters of the model are
determined by comparing masses and tree-level decay widths with experimental
values. We examine the restoration of the chiral symmetry by monitoring the
temperature evolution of condensates. We study the phase diagram of
the model and find that a critical end point exists, although at very low
density.Comment: 5 pages, 2 figures, Presented at CPOD 2016, Wrocla
Chiral phase transition in an extended linear sigma model: initial results
We investigate the scalar meson mass dependence on the chiral phase
transition in the framework of an SU(3), (axial)vector meson extended linear
sigma model with additional constituent quarks and Polyakov loops. We determine
the parameters of the Lagrangian at zero temperature in a hybrid approach,
where we treat the mesons at tree-level, while the constituent quarks at 1-loop
level. We assume two nonzero scalar condensates and together with the
Polyakov-loop variables we determine their temperature dependence according to
the 1-loop level field equations.Comment: Presented at the Workshop on Unquenched Hadron Spectroscopy:
Non-Perturbative Models and Methods of QCD vs. Experiment, At the occasion of
Eef van Beveren's 70th birthda
Probing in-medium vector meson decays by double-differential di-electron spectra in heavy-ion collisions at SIS energies
Within a transport code simulation for heavy-ion collisions at bombarding
energies around 1 AGeV, we demonstrate that double-differential di-electron
spectra with suitable kinematical cuts are useful to isolate (i) the
meson peak even in case of strong broadening, and (ii) the in-medium
decay contribution. The expected in-medium modifications of the vector meson
spectral densities can thus be probed in this energy range via the di-electron
channel
Massive Splenic Pseudocysts : Report of 2 cases
Splenic cysts can be classified as parasitic and nonparasitic. Non parasitic cysts can be further divided into true and pseudocysts. Pseudocysts of spleen does not contain an epithelial lining. Pseudocysts of spleen are usually post traumatic and they rarely grow to a large size and most of them are asymptomatic. It can be confused with cystic lesions of spleen or pancreas or from the surrounding structures. These cases require exploration and is both diagnostic and therapeutic. Conservative measures to preserve spleen can be considered only in presence of expertise and if remnant functional splenic parenchyma is more than 25 %. Here we present two cases of giant pseudocysts who were confused with malignancy and referred to our centre and were later found to be pseudocysts of spleen. We would like to report these cases as they are rare and as diagnostic dilemmas
Trajectories of the S-matrix poles in Salamon-Vertse potential
The trajectories of S-matrix poles are calculated in the finite-range
phenomenological potential introduced recently by P. Salamon and T. Vertse
(SV). The trajectories of the resonance poles in this SV potential are compared
to the corresponding trajectories in a cut-off Woods-Saxon (WS) potential for
l>0. The dependence on the cut-off radius is demonstrated. The starting points
of the trajectories turn out to be related to the average ranges of the two
terms in the SV potential
An elementary proof for the non-bijective version of Wigner's theorem
The non-bijective version of Wigner’s theorem states that a map which is defined on the set of self-adjoint, rank-one projections (or pure states) of a complex Hilbert space and which preserves the transition probability between any two elements, is induced by a linear or antilinear isometry. We present a completely new, elementary and very short proof of this famous theorem which is very important in quantum mechanics. We do not assume bijectivity of the mapping or separability of the underlying space like in many other proofs
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