13,466 research outputs found
Polyadic Entropy, Synergy and Redundancy among Statistically Independent Processes in Nonlinear Statistical Physics with Microphysical Codependence
The information shared among observables representing processes of interest
is traditionally evaluated in terms of macroscale measures characterizing
aggregate properties of the underlying processes and their interactions.
Traditional information measures are grounded on the assumption that the
observable represents a memoryless process without any interaction among
microstates. Generalized entropy measures have been formulated in non-extensive
statistical mechanics aiming to take microphysical codependence into account in
entropy quantification. By taking them into consideration when formulating
information measures, the question is raised on whether and if so how much
information permeates across scales to impact on the macroscale information
measures. The present study investigates and quantifies the emergence of
macroscale information from microscale codependence among microphysics. In
order to isolate the information emergence coming solely from the nonlinearly
interacting microphysics, redundancy and synergy are evaluated among macroscale
variables that are statistically independent from each other but not
necessarily so within their own microphysics. Synergistic and redundant
information are found when microphysical interactions take place, even if the
statistical distributions are factorable. These findings stress the added value
of nonlinear statistical physics to information theory in coevolutionary
systems
Convergence of the Crank-Nicolson-Galerkin finite element method for a class of nonlocal parabolic systems with moving boundaries
The aim of this paper is to establish the convergence and error bounds to the
fully discrete solution for a class of nonlinear systems of reaction-diffusion
nonlocal type with moving boundaries, using a linearized
Crank-Nicolson-Galerkin finite element method with polynomial approximations of
any degree. A coordinate transformation which fixes the boundaries is used.
Some numerical tests to compare our Matlab code with some existing moving
finite elements methods are investigated
Implications of the LHC two-photon signal for two-Higgs-doublet models
We study the implications for Two Higgs Doublet Models of the recent
announcement at the LHC giving a tantalizing hint for a Higgs boson of mass 125
GeV decaying into two photons. We require that the experimental result be
within a factor of two of the theoretical Standard Model prediction, and
analyze the type I and type II models as well as the lepton-specific and
flipped models, subject to this requirement. It is assumed that there is no new
physics other than two Higgs doublets. In all of the models, we display the
allowed region of parameter space taking the recent LHC announcement at face
value, and we analyze the , , and
expectations in these allowed regions. Throughout the entire range of parameter
space allowed by the constraint, the number of events for Higgs
decays into , and are not changed from the Standard Model
by more than a factor of two. In contrast, in the Lepton Specific model, decays
to are very sensitive across the entire -allowed region.Comment: Latex, 6 pages, 4 figures; v2 - added 2 reference
On asymptotically optimal tests under loss of identifiability in semiparametric models
We consider tests of hypotheses when the parameters are not identifiable
under the null in semiparametric models, where regularity conditions for
profile likelihood theory fail. Exponential average tests based on integrated
profile likelihood are constructed and shown to be asymptotically optimal under
a weighted average power criterion with respect to a prior on the
nonidentifiable aspect of the model. These results extend existing results for
parametric models, which involve more restrictive assumptions on the form of
the alternative than do our results. Moreover, the proposed tests accommodate
models with infinite dimensional nuisance parameters which either may not be
identifiable or may not be estimable at the usual parametric rate. Examples
include tests of the presence of a change-point in the Cox model with current
status data and tests of regression parameters in odds-rate models with right
censored data. Optimal tests have not previously been studied for these
scenarios. We study the asymptotic distribution of the proposed tests under the
null, fixed contiguous alternatives and random contiguous alternatives. We also
propose a weighted bootstrap procedure for computing the critical values of the
test statistics. The optimal tests perform well in simulation studies, where
they may exhibit improved power over alternative tests.Comment: Published in at http://dx.doi.org/10.1214/08-AOS643 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
ScannerS: Constraining the phase diagram of a complex scalar singlet at the LHC
We present the first version of a new tool to scan the parameter space of
generic scalar potentials, ScannerS. The main goal of ScannerS is to help
distinguish between different patterns of symmetry breaking for each scalar
potential. In this work we use it to investigate the possibility of excluding
regions of the phase diagram of several versions of a complex singlet extension
of the Standard Model, with future LHC results. We find that if another scalar
is found, one can exclude a phase with a dark matter candidate in definite
regions of the parameter space, while predicting whether a third scalar to be
found must be lighter or heavier. The first version of the code is publicly
available and contains various generic core routines for tree level vacuum
stability analysis, as well as implementations of collider bounds, dark matter
constraints, electroweak precision constraints and tree level unitarity.Comment: 24 pages, 4 figures, 3 tables. Project development webpage -
http://gravitation.web.ua.pt/Scanner
Wrong sign and symmetric limits and non-decoupling in 2HDMs
We analyse the possibility that, in two Higgs doublet models, one or more of
the Higgs couplings to fermions or to gauge bosons change sign, relative to the
respective Higgs Standard Model couplings. Possible sign changes in the
coupling of a neutral scalar to charged ones are also discussed. These
\textit{wrong signs} can have important physical consequences, manifesting
themselves in Higgs production via gluon fusion or Higgs decay into two gluons
or into two photons. We consider all possible wrong sign scenarios, and also
the \textit{symmetric limit}, in all possible Yukawa implementations of the two
Higgs doublet model, in two different possibilities: the observed Higgs boson
is the lightest CP-even scalar, or the heaviest one. We also analyse thoroughly
the impact of the currently available LHC data on such scenarios. With all 8
TeV data analysed, all wrong sign scenarios are allowed in all Yukawa types,
even at the 1 level. However, we will show that B-physics constraints
are crucial in excluding the possibility of wrong sign scenarios in the case
where is below 1. We will also discuss the future prospects for
probing the wrong sign scenarios at the next LHC run. Finally we will present a
scenario where the alignment limit could be excluded due to non-decoupling in
the case where the heavy CP-even Higgs is the one discovered at the LHC.Comment: 20 pages, 15 figure
Mass-degenerate Higgs bosons at 125 GeV in the Two-Higgs-Doublet Model
The analysis of the Higgs boson data by the ATLAS and CMS Collaborations
appears to exhibit an excess of h --> gamma\gamma events above the Standard
Model (SM) expectations; whereas no significant excess is observed in h --> ZZ*
--> {four lepton} events, albeit with large statistical uncertainty due to the
small data sample. These results (assuming they persist with further data)
could be explained by a pair of nearly mass-degenerate scalars, one of which is
a SM-like Higgs boson and the other is a scalar with suppressed couplings to
W+W- and ZZ. In the two Higgs doublet model, the observed \gamma\gamma and ZZ*
--> {four lepton} data can be reproduced by an approximately degenerate CP-even
(h) and CP-odd (A) Higgs boson for values of \sin(\beta-\alpha) near unity and
0.7 < \tan\beta < 1. An enhanced \gamma\gamma signal can also arise in cases
where m_h ~ m_H, m_H ~ m_A, or m_h ~ m_H ~ m_A. Since the ZZ* --> {four lepton}
signal derives primarily from a SM-like Higgs boson whereas the \gamma\gamma
signal receives contributions from two (or more) nearly mass-degenerate states,
one would expect a slightly different invariant mass peak in the ZZ* --> {four
lepton} and \gamma\gamma channels. The phenomenological consequences of such
models can be tested with additional Higgs data that will be collected at the
LHC in the near future.Comment: 18 pages, 19 pdf figures, v2: references added, v3&v4: added refs and
explanation
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