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

Dynamics of a magnetic dimer with exchange, dipolar and Dzyalozhinski-Moriya interaction

We investigate the dynamics of a magnetic system consisting of two magnetic moments coupled by either exchange, dipole-dipole, or Dzyalozhinski-Moriya interaction. We compare the switching mechanisms and switching rates as induced by the three couplings. For each coupling and each configuration of the two anisotropy axes, we describe the switching modes and, using the kinetic theory of Langer, we provide (semi-)analytical expressions for the switching rate. We then compare the three interactions with regard to their efficiency in the reversal of the net magnetic moment of the dimer. We also investigate how the energy barriers vary with the coupling. For the dipole-dipole interaction we find that the energy barrier may either increase or decrease with the coupling depending on whether the latter is weak or strong. Finally, upon comparing the various switching rates, we find that the dipole-dipole coupling leads to the slowest magnetic dimer, as far as the switching of its net magnetic moment is concerned.Comment: 20 pages, 18 Figures, 2 table

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 $>230$ 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

An Evidence Based Time-Frequency Search Method for Gravitational Waves from Pulsar Glitches

We review and expand on a Bayesian model selection technique for the detection of gravitational waves from neutron star ring-downs associated with pulsar glitches. The algorithm works with power spectral densities constructed from overlapping time segments of gravitational wave data. Consequently, the original approach was at risk of falsely identifying multiple signals where only one signal was present in the data. We introduce an extension to the algorithm which uses posterior information on the frequency content of detected signals to cluster events together. The requirement that we have just one detection per signal is now met with the additional bonus that the belief in the presence of a signal is boosted by incorporating information from adjacent time segments.Comment: 6 pages, 4 figures, submitted to AMALDI 7 proceeding

The dynamical Casimir effect in superconducting microwave circuits

We theoretically investigate the dynamical Casimir effect in electrical circuits based on superconducting microfabricated waveguides with tunable boundary conditions. We propose to implement a rapid modulation of the boundary conditions by tuning the applied magnetic flux through superconducting quantum interference devices (SQUIDs) that are embedded in the waveguide circuits. We consider two circuits: (i) An open waveguide circuit that corresponds to a single mirror in free space, and (ii) a resonator coupled to a microfabricated waveguide, which corresponds to a single-sided cavity in free space. We analyze the properties of the dynamical Casimir effect in these two setups by calculating the generated photon-flux density, output-field correlation functions, and the quadrature squeezing spectra. We show that these properties of the output field exhibit signatures unique to the radiation due to the dynamical Casimir effect, and could therefore be used for distinguishing the dynamical Casimir effect from other types of radiation in these circuits. We also discuss the similarities and differences between the dynamical Casimir effect, in the resonator setup, and downconversion of pump photons in parametric oscillators.Comment: 18 pages, 14 figure

The Lorentzian distance formula in noncommutative geometry

For almost twenty years, a search for a Lorentzian version of the well-known Connes' distance formula has been undertaken. Several authors have contributed to this search, providing important milestones, and the time has now come to put those elements together in order to get a valid and functional formula. This paper presents a historical review of the construction and the proof of a Lorentzian distance formula suitable for noncommutative geometry.Comment: 16 pages, final form, few references adde

Quantum two-level systems in Josephson junctions as naturally formed qubits

The two-level systems (TLSs) naturally occurring in Josephson junctions constitute a major obstacle for the operation of superconducting phase qubits. Since these TLSs can possess remarkably long decoherence times, we show that such TLSs can themselves be used as qubits, allowing for a well controlled initialization, universal sets of quantum gates, and readout. Thus, a single current-biased Josephson junction (CBJJ) can be considered as a multiqubit register. It can be coupled to other CBJJs to allow the application of quantum gates to an arbitrary pair of qubits in the system. Our results indicate an alternative way to realize superconducting quantum information processing.Comment: Reference adde