Diffusive foam wetting process in microgravity

We report the experimental study of aqueous foam wetting in microgravity. The liquid fraction $\ell$ along the bubble edges is measured and is found to be a relevant dynamical parameter during the capillary process. The penetration of the liquid in the foam, the foam inflation, and the rigidity loss are shown all to obey strict diffusion processes.Comment: 4 pages, 6 figures, submitted to Phys. Rev. Let

Praising God or singing of love? From theological to erotic allegorisation in the interpretation of Canticles

In the history of the interpretation of Canticles, one generally distinguishes two tendencies, which can also be identified in the interpretation history of the rest of the Old Testament literature. Alongside a literal reading of the text, there is also the possibility of an allegorical interpretation, which was often, consciously or otherwise, a reaction against a literal reading of the Bible. Although this contrast between the terms ‘literal’ and ‘allegorical’ appears frequently in the literature on Canticles, the present article argues that this terminology seems to be inadequate for Canticles at any rate: reading Canticles either ‘literally’ or ‘allegorically’ is an expression of a false dilemma with respect to this book. After all, being love poetry, the book sings about love as a transcendent, even ‘divine’ reality. Againstthis background, this contribution will argue that the so-called ‘literal’ — anthropological — reading, according to which Canticles praises the love between two persons, is, in the case of many authors, at least as allegorical as the so-called theological-allegorical reading, according to which Canticles is supposed to speak about the relationship between God and Israel, or Christ and the Church. Therefore, in the first part of this contribution, we shall briefly consider the background of the theological-allegorical reading of Canticles. Then, we shall examine the anthropological interpretation, which has received renewed attention, especially since the beginning of the twentieth century, and which has rapidly developed into an anthropological-allegorical interpretation. In the third part, the evolutionoutlined in the previous two parts will be illustrated in an analysis of  Canticles 2:16

Contour lines of the discrete scale invariant rough surfaces

We study the fractal properties of the 2d discrete scale invariant (DSI) rough surfaces. The contour lines of these rough surfaces show clear DSI. In the appropriate limit the DSI surfaces converge to the scale invariant rough surfaces. The fractal properties of the 2d DSI rough surfaces apart from possessing the discrete scale invariance property follow the properties of the contour lines of the corresponding scale invariant rough surfaces. We check this hypothesis by calculating numerous fractal exponents of the contour lines by using numerical calculations. Apart from calculating the known scaling exponents some other new fractal exponents are also calculated.Comment: 9 Pages, 12 figure

Cross-correlations between volume change and price change

In finance, one usually deals not with prices but with growth rates $R$, defined as the difference in logarithm between two consecutive prices. Here we consider not the trading volume, but rather the volume growth rate $\tilde R$, the difference in logarithm between two consecutive values of trading volume. To this end, we use several methods to analyze the properties of volume changes $|\tilde R|$, and their relationship to price changes $|R|$. We analyze $14,981$ daily recordings of the S\&P 500 index over the 59-year period 1950--2009, and find power-law {\it cross-correlations\/} between $|R|$ and $|\tilde R|$ using detrended cross-correlation analysis (DCCA). We introduce a joint stochastic process that models these cross-correlations. Motivated by the relationship between $| R|$ and $|\tilde R|$, we estimate the tail exponent ${\tilde\alpha}$ of the probability density function $P(|\tilde R|) \sim |\tilde R|^{-1 -\tilde\alpha}$ for both the S\&P 500 index as well as the collection of 1819 constituents of the New York Stock Exchange Composite index on 17 July 2009. As a new method to estimate $\tilde\alpha$, we calculate the time intervals $\tau_q$ between events where $\tilde R>q$. We demonstrate that $\bar\tau_q$, the average of $\tau_q$, obeys $\bar \tau_q \sim q^{\tilde\alpha}$. We find $\tilde \alpha \approx 3$. Furthermore, by aggregating all $\tau_q$ values of 28 global financial indices, we also observe an approximate inverse cubic law.Comment: 7 pages, 5 figure

Influence of a low magnetic field on the thermal diffusivity of Bi-2212

The thermal diffusivity of a Bi-2212 polycrystalline sample has been measured under a 1T magnetic field applied perpendicularly to the heat flux. The magnetic contribution to the heat carrier mean free path has been extracted and is found to behave as a simple power law. This behavior can be attributed to a percolation process of electrons in the vortex lattice created by the magnetic field.Comment: 10 pages, 3 figures; to be published in Phys. Rev.

Estimation of the charge carrier localization length from Gaussian fluctuations in the magneto-thermopower of La_{0.6}Y_{0.1}Ca_{0.3}MnO_3

The magneto-thermoelectric power (TEP) $\Delta S(T,H)$ of perovskite type manganise oxide $La_{0.6}Y_{0.1}Ca_{0.3}MnO_3$ is found to exhibit a sharp peak at some temperature $T^{*}=170K$. By approximating the true shape of the measured magneto-TEP in the vicinity of $T^{*}$ by a linear triangle of the form $\Delta S(T,H)\simeq S_p(H)\pm B^{\pm}(H)(T^{*}-T)$, we observe that $B ^{-}(H)\simeq 2B ^{+}(H)$. We adopt the electron localization scenario and introduce a Ginzburg-Landau (GL) type theory which incorporates the two concurrent phase transitions, viz., the paramagnetic-ferromagnetic transition at the Curie point $T_C$ and the "metal-insulator" (M-I) transition at $T_{MI}$. The latter is characterized by the divergence of the field-dependent charge carrier localization length $\xi (T,H)$ at some characteristic field $H_0$. Calculating the average and fluctuation contributions to the total magnetization and the transport entropy related magneto-TEP $\Delta S(T,H)$ within the GL theory, we obtain a simple relationship between $T^{*}$ and the above two critical temperatures ($T_{C}$ and $T_{MI}$). The observed slope ratio $B ^{-}(H)/B ^{+}(H)$ is found to be governed by the competition between the electron-spin exchange $JS$ and the induced magnetic energy $M_sH_0$. The comparison of our data with the model predictions produce $T_{C}=195K$, $JS=40meV$, $M_0=0.4M_s$, $\xi_0=10\AA$, and $n_e/n_i=2/3$ for the estimates of the Curie temperature, the exchange coupling constant, the critical magnetization, the localization length, and the free-to-localized carrier number density ratio, respectively.Comment: 6 pages (REVTEX), 2 PS figures (epsf.sty); submitted to Phys.Rev.