Exchange bias effect and intragranular magnetoresistance in Nd$_{0.84}Sr_{0.16}CoO_3

Electrical transport properties as a function of magnetic field and time have been investigated in polycrystalline, Nd_{0.84}Sr_{0.16}CoO_3. A strong exchange bias (EB) effect is observed associated with the fairly large intragranular magnetoresistance (MR). The EB effect observed in the MR curve is compared with the EB effect manifested in magnetic hysteresis loop. Training effect, described as the decrease of EB effect when the sample is successively field-cycled at a particular temperature, has been observed in the shift of the MR curve. Training effect could be analysed by the successful models. The EB effect, MR and a considerable time dependence in MR are attributed to the intrinsic nanostructure giving rise to the varieties of magnetic interfaces in the grain interior

No-go theorems for \psi-epistemic models based on a continuity assumption

The quantum state \psi is a mathematical object used to determine the probabilities of different outcomes when measuring a physical system. Its fundamental nature has been the subject of discussions since the inception of quantum theory: is it ontic, that is, does it correspond to a real property of the physical system? Or is it epistemic, that is, does it merely represent our knowledge about the system? Assuming a natural continuity assumption and a weak separability assumption, we show here that epistemic interpretations of the quantum state are in contradiction with quantum theory. Our argument is different from the recent proof of Pusey, Barrett, and Rudolph and it already yields a non-trivial constraint on \psi-epistemic models using a single copy of the system in question.Comment: Version 1 contains both theory and an illustrative experiment. Version 2 contains only the theory (the experiment with expanded discussion will be posted separatly at a later date). The main novelty of Version 2 is a detailed comparison in appendix 2 with L. Hardy arXiv:1205.14396. Version 2 is 6 pages of text and 1 figure; v3: minor change

Anomalous Triple Gauge Vertices at the Large Hadron-Electron Collider

At a high energy $ep$ collider, such as the Large Hadron-Electron Collider (LHeC) which is being planned at CERN, one can access the $WW\gamma$ vertex exclusively in charged current events with a radiated photon, with no interference from the $WWZ$ vertex. We find that the azimuthal angle between the jet and the missing momentum in each charged current event is a sensitive probe of anomalous $WW\gamma$ couplings, and show that for quite reasonable values of integrated luminosity, the LHeC can extend the discovery reach for these couplings beyond all present experimental bounds.Comment: 11 pages, LaTeX2e, 5 EPS figure

Predictability of stock returns using financial statement information: Evidence on semi-strong efficiency of emerging Greek stock market

This article examines the predictability of stock returns in the Athens Stock Exchange (ASE) during 1993 to 2006 by using accounting information. Using panel data analysis, this article concludes that the selected set of financial ratios contains significant information for predicting the cross-section of stock returns. Results indicate that portfolios selected on the basis of financial ratios produce higher than average returns, suggesting that the emerging Greek market does not fully incorporate accounting information into stock prices and hence it is not semi-strong efficient