1,578 research outputs found
IS A TAX CUT ON CULTURAL GOODS CONSUMPTION ACTUALLY DESIRABLE?:A MICROSIMULATION ANALYSIS
Proposals for tax cuts on cultural goods represent an ongoing debate in cultural policy. The main aim of this paper is to shed some light on this debate using microsimulation tools. First, we have estimated an Almost Ideal Demand System for nineteen different groups of goods, including cultural goods. Expenditure and price elasticities have been obtained from this model. Using this information, three alternatives cuts in the V.A.T. rate on cultural goods have been microsimulated and evaluated in terms of revenue and welfare. These types of fiscal reforms will lead to welfare and efficiency gains that can be described as regressive.Microsimulation, tax reforms, cultural consumption, welfare
A few words about Resonances in the Electroweak Effective Lagrangian
Contrary to a widely spread believe, we have demonstrated that strongly
coupled electroweak models including both a light Higgs-like boson and massive
spin-1 resonances are not in conflict with experimental constraints on the
oblique S and T parameters. We use an effective Lagrangian implementing the
chiral symmetry breaking SU(2)_L x SU(2)_R -> SU(2)_{L+R} that contains the
Standard Model gauge bosons coupled to the electroweak Goldstones, one
Higgs-like scalar state h with mass m_h=126 GeV and the lightest vector and
axial-vector resonance multiplets V and A. We have considered the one-loop
calculation of S and T in order to study the viability of these
strongly-coupled scenarios, being short-distance constraints and dispersive
relations the main ingredients of the calculation. Once we have constrained the
resonance parameters, we do a first approach to the determination of the low
energy constants of the electroweak effective theory at low energies (without
resonances). We show this determination in the case of the purely Higgsless
bosonic Lagrangian.Comment: 6 pages, 2 figures. Talk given at XIth Quark Confinement and Hadron
Spectrum, 8-12th September (2014), Saint Petersburg (Russia
Fingerprints of heavy scales in electroweak effective Lagrangians
The couplings of the electroweak effective theory contain information on the
heavy-mass scales which are no-longer present in the low-energy Lagrangian. We
build a general effective Lagrangian, implementing the electroweak chiral
symmetry breaking , which couples the
known particle fields to heavier states with bosonic quantum numbers
and . We consider colour-singlet heavy fields that are in
singlet or triplet representations of the electroweak group. Integrating out
these heavy scales, we analyze the pattern of low-energy couplings among the
light fields which are generated by the massive states. We adopt a generic
non-linear realization of the electroweak symmetry breaking with a singlet
Higgs, without making any assumption about its possible doublet structure.
Special attention is given to the different possible descriptions of massive
spin-1 fields and the differences arising from naive implementations of these
formalisms, showing their full equivalence once a proper short-distance
behaviour is required.Comment: 57 pages, 1 pdf figure. Version published at JHE
Positivity constraints on the low-energy constants of the chiral pion-nucleon Lagrangian
Positivity constraints on the pion-nucleon scattering amplitude are derived
in this article with the help of general S-matrix arguments, such as
analyticity, crossing symmetry and unitarity, in the upper part of Mandelstam
triangle, R. Scanning inside the region R, the most stringent bounds on the
chiral low energy constants of the pion-nucleon Lagrangian are determined. When
just considering the central values of the fit results from covariant baryon
chiral perturbation theory using extended-on-mass-shell scheme, it is found
that these bounds are well respected numerically both at O(p^3) and O(p^4)
level. Nevertheless, when taking the errors into account, only the O(p^4)
bounds are obeyed in the full error interval, while the bounds on O(p^3) fits
are slightly violated. If one disregards loop contributions, the bounds always
fail in certain regions of R. Thus, at a given chiral order these terms are not
numerically negligible and one needs to consider all possible contributions,
i.e., both tree-level and loop diagrams. We have provided the constraints for
special points in R where the bounds are nearly optimal in terms of just a few
chiral couplings, which can be easily implemented and employed to constrain
future analyses. Some issues about calculations with an explicit Delta(1232)
resonance are also discussed.Comment: 15 pages, 13 eps figures, 2 table
One-loop renormalization of the electroweak chiral Lagrangian with a light Higgs
We consider the general chiral effective action which parametrizes the
nonlinear realization of the spontaneous breaking of the electroweak symmetry
with a light Higgs, and compute the one-loop ultraviolet divergences coming
from Higgs and electroweak Goldstone fluctuations using the background field
method. The renormalization of the divergences is carried out through operators
of next-to-leading order in the chiral counting, i.e. of O(p^4). Being of the
same order in power counting, the logarithmic corrections linked to these
divergences can be as important as the tree-level contributions from the O(p^4)
operators, and must be accounted for in the phenomenological analysis of
experimental data. Deviations in the O(p^2) (leading-order) couplings with
respect to the Standard Model values, e.g., in the h->WW coupling, would
generate contributions from the 1-loop chiral logarithms computed in this work
to a vast variety of observables, which do not have a counterpart in the
conventional electroweak effective theory with a linearly transforming Higgs
complex doublet.Comment: 6 page
- …