Towards violation of Born's rule: description of a simple experiment

Recently a new model with hidden variables of the wave type was elaborated, so called prequantum classical statistical field theory (PCSFT). Roughly speaking PCSFT is a classical signal theory applied to a special class of signals -- "quantum systems". PCSFT reproduces successfully all probabilistic predictions of QM, including correlations for entangled systems. This model peacefully coexists with all known no-go theorems, including Bell's theorem. In our approach QM is an approximate model. All probabilistic predictions of QM are only (quite good) approximations of "real physical averages". The latter are averages with respect to fluctuations of prequantum fields. In particular, Born's rule is only an approximate rule. More precise experiments should demonstrate its violation. We present a simple experiment which has to produce statistical data violating Born's rule. Since the PCSFT-presentation of this experiment may be difficult for experimenters, we reformulate consequences of PCSFT in terms of the conventional wave function. In general, deviation from Born's rule is rather small. We found an experiment amplifying this deviation. We start with a toy example in section 2. Then we present a more realistic example based on Gaussian states with very small dispersion, see section 3.Comment: The paper was completed with the description of an experiment with Gaussian states with very small dispersion. This experiment should induce violation of Born's rule, the fundamental law of Q

A Fast and Compact Quantum Random Number Generator

We present the realization of a physical quantum random number generator based on the process of splitting a beam of photons on a beam splitter, a quantum mechanical source of true randomness. By utilizing either a beam splitter or a polarizing beam splitter, single photon detectors and high speed electronics the presented devices are capable of generating a binary random signal with an autocorrelation time of 11.8 ns and a continuous stream of random numbers at a rate of 1 Mbit/s. The randomness of the generated signals and numbers is shown by running a series of tests upon data samples. The devices described in this paper are built into compact housings and are simple to operate.Comment: 23 pages, 6 Figs. To appear in Rev. Sci. Inst

Boxfishes (Teleostei: Ostraciidae) as a model system for fishes swimming with many fins: kinematics

Swimming movements in boxfishes were much more complex and varied than classical descriptions indicated. At low to moderate rectilinear swimming speeds (<5 TL s^(-1), where TL is total body length), they were entirely median- and paired-fin swimmers, apparently using their caudal fins for steering. The pectoral and median paired fins generate both the thrust needed for forward motion and the continuously varied, interacting forces required for the maintenance of rectilinearity. It was only at higher swimming speeds (above 5 TL s^(-1)), when burst-and-coast swimming was used, that they became primarily body and caudal-fin swimmers. Despite their unwieldy appearance and often asynchronous fin beats, boxfish swam in a stable manner. Swimming boxfish used three gaits. Fin-beat asymmetry and a relatively nonlinear swimming trajectory characterized the first gait (0–1 TL s^(-1)). The beginning of the second gait (1–3 TL s^(-1)) was characterized by varying fin-beat frequencies and amplitudes as well as synchrony in pectoral fin motions. The remainder of the second gait (3–5 TL s^(-1)) was characterized by constant fin-beat amplitudes, varying finbeat frequencies and increasing pectoral fin-beat asynchrony. The third gait (>5 TL s^(-1)) was characterized by the use of a caudal burst-and-coast variant. Adduction was always faster than abduction in the pectoral fins. There were no measurable refractory periods between successive phases of the fin movement cycles. Dorsal and anal fin movements were synchronized at speeds greater than 2.5 TL s^(-1), but were often out of phase with pectoral fin movements

A lottery incentive system to facilitate dialogue and social support for workplace HIV counselling and testing: A qualitative inquiry

Despite South African mid-sized companies’ efforts to offer HIV counselling and testing (HCT) in the workplace, companies report relatively poor uptake rates. An urgent need for a range of different interventions aimed at increasing participation in workplace HCT has been identified. The aim of this study was to explore qualitatively the influence of a lottery incentive system (LIS) as an intervention to influence shop-floor workers’ workplace HIV testing behaviour. A qualitative study was conducted among 17 shop-floor workers via convenience sampling in two mid-sized South African automotive manufacturing companies in which an LIS for HCT was implemented. The in-depth interviews employed a semi-structured interview schedule and thematic analysis was used to analyse the data. The interviews revealed that the LIS created excitement in the companies and renewed employees’ personal interest in HCT. The excitement facilitated social interactions that resulted in a strong group cohesion pertaining to HCT that mitigated the burden of HIV stigma in the workplace. Open discussions allowed for the development of supportive social group pressure to seek HCT as a collective in anticipation of a reward. Lotteries were perceived as a supportive and innovative company approach to workplace HCT. The study identified important aspects for consideration by companies when using an LIS to enhance workplace HIV testing. The significance of inter- and intra-player dialogue in activating supportive social norms for HIV testing in collectivist African contexts was highlighted.Keywords: HCT, company, collectivist, group pressure, norm, South AfricaMalgre´ les efforts que font les petites et moyennes entreprises sud-africaines pour offrir le conseil et de´pistage volontaire du VIH (CDV) en milieu de travail, les entreprises font e´tat de taux de participation relativement bas. Un besoin urgent pour une gamme de diffe´rentes interventions visant a` accroıˆtre la participation au CDV en milieu de travail a e´te´ identifie´e. Le but de cette e´tude e´tait d’e´tudier qualitativement l’influence d’un syste`me d’incitation a` la loterie comme intervention pour influencer le comportement CDV des ouvriers en milieu de travail. Une e´tude qualitative a e´te´ mene´e aupre`s de 17 ouvriers choisis par e´chantillonnage de commodite´ dans 2 entreprises de fabrication automobile en Afrique du Sud. Dans ces 2 entreprises de taille moyenne, un syste`me d’incitation a` la loterie a e´te´ mis en oeuvre pour encourager le CDV en milieu de travail. Un guide d’interviews semistructure ´es a e´te´ employe´ pour mener des entretiens approfondis. L’analyse the´matique a e´te´ utilise´e pour analyser les donne´es. Les entrevues ont re´ve´le´ que les syste`mes d’incitation ont cre´e´ de l’excitation dans les entreprises et ont renouvele´ l’inte´reˆt personnel des employe´s pour le CDV. L’excitation a facilite´ des interactions sociales qui ont abouti a` une forte cohe´sion du groupe d’ouvriers concernant le CDV et atte´nuant ainsi la stigmatisation lie´e au VIH en milieu de travail. Des discussions ouvertes ont permis l’e´laboration de pression sociale de groupe en support a` la participation collective au CDV en pre´vision d’une re´compense. Les loteries ont e´te´ perc¸ues comme une approche soutenante et innovante de la part des entreprises pour le CDV en milieu de travail. L’e´tude a identifie´ des aspects importants a` prendre en compte par les entreprises lors de l’utilisation d’un syste`me d’incitation a` la loterie pour augmenter le taux de de´pistage VIH en milieu de travail. L’importance du dialogue inter- et intra-joueur dans l’activation de normes sociales favorables pour le de´pistage VIH dans les contextes collectivistesafricains a e´te´ souligne´e.Mots cle´s: CDV, entreprise, collectiviste, pression de groupe, norme, Afrique du Su

Comment on "Exclusion of time in the theorem of Bell" by K. Hess and W. Philipp

A recent Letter by Hess and Philipp claims that Bell's theorem neglects the possibility of time-like dependence in local hidden variables, hence is not conclusive. Moreover the authors claim that they have constructed, in an earlier paper, a local realistic model of the EPR correlations. However, they themselves have neglected the experimenter's freedom to choose settings, while on the other hand, Bell's theorem can be formulated to cope with time-like dependence. This in itself proves that their toy model cannot satisfy local realism, but we also indicate where their proof of its local realistic nature fails.Comment: Latex needs epl.cl

Modally Resolved Fabry-Perot Experiment with Semiconductor Waveguides

Based on the interaction between different spatial modes, semiconductor Bragg-reflection waveguides provide a highly functional platform for non-linear optics. Therefore, the control and engineering of the properties of each spatial mode is essential. Despite the multimodeness of our waveguide, the well-established Fabry-Perot technique for recording fringes in the optical transmission spectrum can successfully be employed for a detailed linear optical characterization when combined with Fourier analysis. A prerequisite for the modal sensitivity is a finely resolved transmission spectrum that is recorded over a broad frequency band. Our results highlight how the features of different spatial modes, such as their loss characteristics and dispersion properties, can be separated from each other allowing their comparison. The mode-resolved measurements are important for optimizing the performance of such multimode waveguides by tailoring the properties of their spatial modes.Comment: 8 pages, 7 figure

Lyapunov exponent for stochastic time series

This paper deals with the problem of the discrimination between stable and unstable time series. One criterion for the seperation is given by the size of the Lyapunov exponent, which was originally defined for deterministic systems. However, this paper will show, that the Lyapunov exponent can also be analyzed and used for ergodic stochastic time series. Experimantal results illustrate the classification by the Lyapunov exponent. Although the Lyapunov exponent is a discriminatory parameter of the asymptotic behavior and can be interpreted as a parameter of the asymptotic distribution in the stochastic case, it has to be estimated from a given time series, where the process might still be in the transient state. Experimental results will show that in special cases the estimation leads to misclassifications of the time series and the underlying process due to the uncertainty of estimators for the Lyapunov exponent. --

Variance Reduction with Monte Carlo Estimates of Error Rates in Multivariate Classification

In this paper, control variates are proposed to speed up Monte Carlo Simulations to estimate expected error rates in multivariate classification