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Scalar mesons nonet in a scaled effective Lagrangian
A scaled SU(3) Nambu - Jona-Lasinio Lagrangian is used to compute the mass of
the nine scalar mesons in the vacuum and the mass of the gluball. It is shown
that a suitable choice of the vacuum gluon condensate allows to reproduce the
experimental masses of the scalar mesons except for the {}(1430). This
choice corresponds to a weak coupling between the gluon and quark condensates,
giving a {}(1500) or a {}(1710) which is nearly a pure glueball.Comment: 12 pages, Latex, use elsart.st
Fluctuation theorem for black-body radiation
The fluctuation theorem is verified for black-body radiation, provided the
bunching of photons is taken into account appropriately.Comment: 4 pages, 3 figure
Comment on "Conductance fluctuations in mesoscopic normal-metal/superconductor samples"
Recently, Hecker et al. [Phys. Rev. Lett. 79, 1547 (1997)] experimentally
studied magnetoconductance fluctuations in a mesoscopic Au wire connected to a
superconducting Nb contact. They claimed to have observed an enhancement of the
rms magnitude of these conductance fluctuations in the superconducting state
(rms(Gns)) relative to that in the normal state (rms(Gn)) by a factor of 2.8.
In this comment, we argue that the measured rms(Gns) is NOT significantly
enhanced compared to rms(Gn) when we correct for the presence of an incoherent
series resistance from the contacts, which is different when Nb is in the
superconducting or normal state.Comment: 1 pag
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