38,090 research outputs found
Recommended from our members
A quantum theoretical explanation for probability judgment errors
A quantum probability model is introduced and used to explain human probability judgment errors including the conjunction, disjunction, inverse, and conditional fallacies, as well as unpacking effects and partitioning effects. Quantum probability theory is a general and coherent theory based on a set of (von Neumann) axioms which relax some of the constraints underlying classic (Kolmogorov) probability theory. The quantum model is compared and contrasted with other competing explanations for these judgment errors including the representativeness heuristic, the averaging model, and a memory retrieval model for probability judgments. The quantum model also provides ways to extend Bayesian, fuzzy set, and fuzzy trace theories. We conclude that quantum information processing principles provide a viable and promising new way to understand human judgment and reasoning
A spectral-based numerical method for Kolmogorov equations in Hilbert spaces
We propose a numerical solution for the solution of the
Fokker-Planck-Kolmogorov (FPK) equations associated with stochastic partial
differential equations in Hilbert spaces.
The method is based on the spectral decomposition of the Ornstein-Uhlenbeck
semigroup associated to the Kolmogorov equation. This allows us to write the
solution of the Kolmogorov equation as a deterministic version of the
Wiener-Chaos Expansion. By using this expansion we reformulate the Kolmogorov
equation as a infinite system of ordinary differential equations, and by
truncation it we set a linear finite system of differential equations. The
solution of such system allow us to build an approximation to the solution of
the Kolmogorov equations. We test the numerical method with the Kolmogorov
equations associated with a stochastic diffusion equation, a Fisher-KPP
stochastic equation and a stochastic Burgers Eq. in dimension 1.Comment: 28 pages, 10 figure
Hybridized solid-state qubit in the charge-flux regime
Most superconducting qubits operate in a regime dominated by either the
electrical charge or the magnetic flux. Here we study an intermediate case: a
hybridized charge-flux qubit with a third Josephson junction (JJ) added into
the SQUID loop of the Cooper-pair box. This additional JJ allows the optimal
design of a low-decoherence qubit. Both charge and flux noises are
considered. Moreover, we show that an efficient quantum measurement of either
the current or the charge can be achieved by using different area sizes for the
third JJ.Comment: 7 pages, 5 figures. Phys. Rev. B, in pres
Stability of real parametric polynomial discrete dynamical systems
We extend and improve the existing characterization of the dynamics of
general quadratic real polynomial maps with coefficients that depend on a
single parameter , and generalize this characterization to cubic real
polynomial maps, in a consistent theory that is further generalized to real
-th degree real polynomial maps. In essence, we give conditions for the
stability of the fixed points of any real polynomial map with real fixed
points. In order to do this, we have introduced the concept of Canonical
Polynomial Maps which are topologically conjugate to any polynomial map of the
same degree with real fixed points. The stability of the fixed points of
canonical polynomial maps has been found to depend solely on a special function
termed Product Position Function for a given fixed point. The values of this
product position determine the stability of the fixed point in question, when
it bifurcates, and even when chaos arises, as it passes through what we have
termed stability bands. The exact boundary values of these stability bands are
yet to be calculated for regions of type greater than one for polynomials of
degree higher than three.Comment: 23 pages, 4 figures, now published in Discrete Dynamics in Nature and
Societ
On the heating of source of the Orion KL hot core
We present images of the J=10-9 rotational lines of HC3N in the vibrationally
excited levels 1v7, 1v6 and 1v5 of the hot core (HC) in Orion KL. The images
show that the spatial distribution and the size emission from the 1v7 and 1v5
levels are different. While the J=10-9 1v7 line has a size of 4''x 6'' and
peaks 1.1'' NE of the 3 mm continuum peak, the J=10--9 1v5 line emission is
unresolved (<3'') and peaks 1.3'' south of the 3 mm peak. This is a clear
indication that the HC is composed of condensations with very different
temperatures (170 K for the 1v7 peak and K for the 1v5 peak). The
temperature derived from the 1v7 and 1v5 lines increases with the projected
distance to the suspected main heating source I. Projection effects along the
line of sight could explain the temperature gradient as produced by source I.
However, the large luminosity required for source I, >5 10^5 Lsolar, to explain
the 1v5 line suggests that external heating by this source may not dominate the
heating of the HC. Simple model calculations of the vibrationally excited
emission indicate that the HC can be internally heated by a source with a
luminosity of 10^5 Lsolar, located 1.2'' SW of the 1v5 line peak (1.8'' south
of source I). We also report the first detection of high-velocity gas from
vibrationally excited HC3N emission. Based on excitation arguments we conclude
that the main heating source is also driving the molecular outflow. We
speculate that all the data presented in this letter and the IR images are
consistent with a young massive protostar embedded in an edge-on disk.Comment: 13 pages, 3 figures, To be published in Ap.J. Letter
Correlation-induced suppression of decoherence in capacitively coupled Cooper-pair boxes
Charge fluctuations from gate bias and background traps severely limit the
performance of a charge qubit in a Cooper-pair box (CPB). Here we present an
experimentally realizable method to control the decoherence effects of these
charge fluctuations using two strongly capacitively coupled CPBs. This
coupled-box system has a low-decoherence subspace of two states. Our results
show that the inter-box Coulomb correlation can help significantly suppress
decoherence of this two-level system, making it a promising candidate as a
logical qubit, encoded using two CPBs.Comment: 5 pages, 2 figures. Phys. Rev. B, in pres
- …