9,611 research outputs found
INFLATION TARGET ZONES AS A COMMITMENT MECHANISM
In a simple new keyenesian model of monetary policy under discretion constraining the Central Bank to put inflation within a pre-specified Inflation Target Zone can eliminate the inflation bias and, at least for certain parameter ranges, significantly reduce the stabilization bias. Also, it is possible to investigate what is the optimal Inflation Target Zone for different economies. These seem to depend of the structural parameters in a non-linear and often non-monotonic way.
"A Theory of Production" The Estimation of the Cobb-Douglas Function: A Retrospective View
The Cobb-Douglas production function is still today the most ubiquitous form in theoretical and empirical analyses of growth and productivity. The estimation of the parameters of aggregate production functions is central to much of today's work on growth, technological change, productivity, and labor. This paper has taken up Samuelson's [1979] invitation to verify empirically his claim that all the regression of the Cobb-Douglas [1928] production function does is to reproduce the income accounting identity according to which value added equals the sum of the wage bill plus total profits. This paper concludes that Samuelson was right, and believes that this argument has very serious implications for today's work in macroeconomics.
Radiatively Induced Lorentz and CPT Violation in Schwinger Constant Field Approximation
The Schwinger proper-time method is an effective calculation method,
explicitly gauge invariant and nonperturbative. We make use of this method to
investigate the radiatively induced Lorentz and CPT-violating effects in
quantum electrodynamics when an axial vector interaction term is introduced in
the fermionic sector. The induced Lorentz and CPT-violating Chern-Simons term
coincides with the one obtained using a covariant derivative expansion but
differs from the result usually obtained in other regularization schemes. A
possible ambiguity in the approach is also discussed.Comment: 11 pages, REVTeX, typos and a few equations corrected, a comment
added to the conclusions, acknowledgments adde
Extracting Information from Qubit-Environment Correlations
Most works on open quantum systems generally focus on the reduced physical
system by tracing out the environment degrees of freedom. Here we show that the
qubit distributions with the environment are essential for a thorough analysis,
and demonstrate that the way that quantum correlations are distributed in a
quantum register is constrained by the way in which each subsystem gets
correlated with the environment. For a two-qubit system coupled to a common
dissipative environment , we show how to optimise interqubit
correlations and entanglement via a quantification of the qubit-environment
information flow, in a process that, perhaps surprisingly, does not rely on the
knowledge of the state of the environment. To illustrate our findings, we
consider an optically-driven bipartite interacting qubit system under the
action of . By tailoring the light-matter interaction, a
relationship between the qubits early stage disentanglement and the
qubit-environment entanglement distribution is found. We also show that, under
suitable initial conditions, the qubits energy asymmetry allows the
identification of physical scenarios whereby qubit-qubit entanglement minima
coincide with the extrema of the and entanglement
oscillations.Comment: 4 figures, 9 page
A new bridge between leptonic CP violation and leptogenesis
Flavor effects due to lepton interactions in the early Universe may have
played an important role in the generation of the cosmological baryon asymmetry
through leptogenesis. If the only source of high-energy CP violation comes from
the left-handed leptonic sector, then it is possible to establish a bridge
between flavored leptogenesis and low-energy leptonic CP violation. We explore
this connection taking into account our present knowledge about low-energy
neutrino parameters and the matter-antimatter asymmetry observed in the
Universe. In this framework, we find that leptogenesis favors a hierarchical
light neutrino mass spectrum, while for quasi-degenerate and inverted
hierarchical neutrino masses there is a very narrow allowed window. The
absolute neutrino mass scale turns out to be m < 0.1 eV.Comment: 10 pages, 3 figure
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