4,563 research outputs found
Vacuum condensates, flavor mixing and spontaneous supersymmetry breaking
Spontaneous supersymmetry (SUSY) breaking is revealed in all phenomena in
which vacuum condensates are physically relevant. The dynamical breakdown of
SUSY is generated by the condensates themselves, which lift the zero point
energy. Evidence is presented in the case of the Wess-Zuimino model, and the
flavor mixing case is treated in detail.Comment: 5 page
Vacuum condensates as a mechanism of spontaneous supersymmetry breaking
A possible mechanism for the spontaneous breaking of SUSY, based on the
presence of vacuum condensates, is reviewed. Such a mechanism could occur in
many physical examples, both at the fundamental and emergent level, and would
be formally analogous to spontaneous SUSY breaking at finite temperature in the
TFD formalism, in which case it can be applied as well. A possible experimental
setup for detecting such a breaking through measurement of the Anandan-Aharonov
invariants associated with vacuum condensates in an optical lattice model is
proposed.Comment: 6 pages, 2 figures, review article to appear in the special issue
"Supersymmetry, Supergravity, and Superstring Phenomenology" of Advances in
High Energy Physic
Extracting the Italian output gap: a Bayesian approach
During the last decades particular effort has been directed towards
understanding and predicting the relevant state of the business cycle with the
objective of decomposing permanent shocks from those having only a transitory
impact on real output. This trend--cycle decomposition has a relevant impact on
several economic and fiscal variables and constitutes by itself an important
indicator for policy purposes. This paper deals with trend--cycle decomposition
for the Italian economy having some interesting peculiarities which makes it
attractive to analyse from both a statistic and an historical perspective. We
propose an univariate model for the quarterly real GDP, subsequently extended
to include the price dynamics through a Phillips curve. This study considers a
series of the Italian quarterly real GDP recently released by OECD which
includes both the 1960s and the recent global financial crisis of 2007--2008.
Parameters estimate as well as the signal extraction are performed within the
Bayesian paradigm which effectively handles complex models where the parameters
enter the log--likelihood function in a strongly nonlinear way. A new Adaptive
Independent Metropolis--within--Gibbs sampler is then developed to efficiently
simulate the parameters of the unobserved cycle. Our results suggest that
inflation influences the Output Gap estimate, making the extracted Italian OG
an important indicator of inflation pressures on the real side of the economy,
as stated by the Phillips theory. Moreover, our estimate of the sequence of
peaks and troughs of the Output Gap is in line with the OECD official dating of
the Italian business cycle
Mixing-induced Spontaneous Supersymmetry Breaking
It is conjectured that flavor mixing furnishes a universal mechanism for the
spontaneous breaking of supersymmetry. The conjecture is proved explicitly for
the mixing of two Wess--Zumino supermultiplets and arguments
for its general validity are given. The mechanism relies on the fact that,
despite mixing treats fermions and bosons symmetrically, both the fermionic and
the bosonic zero point energies are shifted by a positive amount and this kind
of shift does not respect supersymmetry.Comment: 5 pages, 1 figure, Eq(12) of V1 corrected to Eq(22), explicit
off-shell formulation included, one reference adde
GPGPU for track finding in High Energy Physics
The LHC experiments are designed to detect large amount of physics events
produced with a very high rate. Considering the future upgrades, the data
acquisition rate will become even higher and new computing paradigms must be
adopted for fast data-processing: General Purpose Graphics Processing Units
(GPGPU) is a novel approach based on massive parallel computing. The intense
computation power provided by Graphics Processing Units (GPU) is expected to
reduce the computation time and to speed-up the low-latency applications used
for fast decision taking. In particular, this approach could be hence used for
high-level triggering in very complex environments, like the typical inner
tracking systems of the multi-purpose experiments at LHC, where a large number
of charged particle tracks will be produced with the luminosity upgrade. In
this article we discuss a track pattern recognition algorithm based on the
Hough Transform, where a parallel approach is expected to reduce dramatically
the execution time.Comment: 6 pages, 4 figures, proceedings prepared for GPU-HEP 2014 conference,
submitted to DESY-PROC-201
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