20,463 research outputs found
Stability of Tsallis antropy and instabilities of Renyi and normalized Tsallis entropies: A basis for q-exponential distributions
The q-exponential distributions, which are generalizations of the
Zipf-Mandelbrot power-law distribution, are frequently encountered in complex
systems at their stationary states. From the viewpoint of the principle of
maximum entropy, they can apparently be derived from three different
generalized entropies: the Renyi entropy, the Tsallis entropy, and the
normalized Tsallis entropy. Accordingly, mere fittings of observed data by the
q-exponential distributions do not lead to identification of the correct
physical entropy. Here, stabilities of these entropies, i.e., their behaviors
under arbitrary small deformation of a distribution, are examined. It is shown
that, among the three, the Tsallis entropy is stable and can provide an
entropic basis for the q-exponential distributions, whereas the others are
unstable and cannot represent any experimentally observable quantities.Comment: 20 pages, no figures, the disappeared "primes" on the distributions
are added. Also, Eq. (65) is correcte
Exponents of 2-multiarrangements and multiplicity lattices
We introduce a concept of multiplicity lattices of 2-multiarrangements,
determine the combinatorics and geometry of that lattice, and give a criterion
and method to construct a basis for derivation modules effectively.Comment: 14 page
-cofiniteness of 2-cyclic permutation orbifold models
In this article, we consider permutation orbifold models of -cofinite
vertex operator algebras of CFT type. We show the -cofiniteness of the
2-cyclic permutation orbifold model for an arbitrary
-cofinite simple vertex operator algebra of CFT type. We also give a
proof of the -cofiniteness of a -orbifold model of the
lattice vertex operator algebra associated with a rank one positive
definite even lattice by using our result and the -cofiniteness of
.Comment: 25 pages, no figure, some typo are correcte
On Observing Top Quark Production at the Tevatron
A technique for separating top quark production from Standard Model
background events is introduced. It is applicable to the channel in which one
top quark decays semi-leptonically and its anti-quark decays hadronically into
three jets, or vice versa. The method is shown to discriminate dramatically
between Monte Carlo generated events with and without simulated top quarks of
mass around 120 GeV and above. The simulations were performed with CDF detector
characteristics incorporated, showing that the method is applicable to existing
data.Comment: 8 pages, TUFTS-TH-92-G01 (Two minor TeX mistakes corrected
Negative s and Light New Physics
Motivated by the difference between SLD's recent measurement of ALR and the
corresponding LEP results, we explore which kinds of new particles can (1)
contribute dominantly to new physics through oblique corrections, (2) produce
negative values for S and T, and (3) not be in conflict with any other
experiments, on or off the Z resonance. We are typically led to models which
involve new particles which are not much heavier than MZ/2, and so which may
also have implications for other experiments in the near future. For such light
particles, we show how the oblique-parameter analysis of purely Z-pole data
requires the interpretation of the data in terms of modified parameters, S' and
T', whose difference from S and T improves the available parameter space of the
models.Comment: plain TeX, 16 pages, 6 figures attached as a uuencoded file,
McGill-94/27, NEIP-94-00
IKT approach for quantum hydrodynamic equations
A striking feature of standard quantum mechanics is its analogy with
classical fluid dynamics. In particular it is well known the Schr\"{o}dinger
equation can be viewed as describing a classical compressible and non-viscous
fluid, described by two (quantum) fluid fields {\rho ,% \mathbf{V}} , to be
identified with the quantum probability density and velocity field. This
feature has suggested the construction of a phase-space hidden-variable
description based on a suitable inverse kinetic theory (IKT; Tessarotto et al.,
2007). The discovery of this approach has potentially important consequences
since it permits to identify the classical dynamical system which advances in
time the quantum fluid fields. This type of approach, however requires the
identification of additional fluid fields. These can be generally identified
with suitable directional fluid temperatures (for ), to be
related to the expectation values of momentum fluctuations appearing in the
Heisenberg inequalities. Nevertheless the definition given previously for them
(Tessarotto et al., 2007) is non-unique. In this paper we intend to propose a
criterion, based on the validity of a constant H-theorem, which provides an
unique definition for the quantum temperatures.Comment: Contributed paper at RGD26 (Kyoto, Japan, July 2008
Three-Jet Event Orientation in e+e- Annihilation: New Tests of the Standard Model
We discuss the orientation of e+e- -> q qbar g events in terms of the polar
and azimuthal angles of the event plane w.r.t. the electron beam direction. We
define an asymmetry of the azimuthal-angle distribution, which, along with the
left-right forward-backward polar-angle asymmetry, is sensitive to
parity-violating effects in three-jet events; these have yet to be explored
experimentally. We have evaluated these observables at O(alpha_s) in
perturbative QCD and present their dependence on longitudinal beam polarisation
and c.m. energy. We also define a moments analysis in terms of the orientation
angles that allows a new and more detailed test of QCD by isolating the six
independent helicity cross-sections.Comment: 15 pages, 5 figures in eps format. This version replaces the garbled
Figure 2 in the original submission. Submitted to Physics Letters B
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