Implication of Cotton Price Behavior on Market Integration

The cotton market in China is highly interactive with international markets, especially, the US market. The prices in these two markets can reveal important market relations. Investigating the data of futures prices from the New York Board of Trade (NYBOT) and the Zhengzhou Commodity Exchange (CZCE) using several time series methods, we find a long-run cointegration relationship between these I(1) series. Furthermore, a bi-directional Granger Causality between these two futures markets is detected with Generalized Autoregressive Conditional Heteroskedasticity (GARCH) error specifications. We also find the relationship is impacted by the Chinese exchange rate policy change in the 2005.cotton futures prices, cointegration, granger causality test, AR-GARCH., Agricultural Finance,

Trade and Integration of the US and China’s Cotton Markets

The cotton market in China is highly interactive with international markets, especially, the US market. The prices in these two markets can reveal important market relations. Investigating the data of futures prices from the New York Board of Trade (NYBOT) and the Zhengzhou Commodity Exchange (CZCE) using several time series methods, we find a long-run cointegration relationship between these I(1) series. Furthermore, a bi-directional Granger Causality between these two futures markets is detected with Generalized Autoregressive Conditional Heteroskedasticity (GARCH) error specifications. We also find the relationship is impacted by the Chinese exchange rate policy change in the 2005.cotton futures prices, cointegration, granger causality test, AR-GARCH, Agricultural Finance, Demand and Price Analysis, International Relations/Trade,

CAPTCHaStar! A novel CAPTCHA based on interactive shape discovery

Over the last years, most websites on which users can register (e.g., email providers and social networks) adopted CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) as a countermeasure against automated attacks. The battle of wits between designers and attackers of CAPTCHAs led to current ones being annoying and hard to solve for users, while still being vulnerable to automated attacks. In this paper, we propose CAPTCHaStar, a new image-based CAPTCHA that relies on user interaction. This novel CAPTCHA leverages the innate human ability to recognize shapes in a confused environment. We assess the effectiveness of our proposal for the two key aspects for CAPTCHAs, i.e., usability, and resiliency to automated attacks. In particular, we evaluated the usability, carrying out a thorough user study, and we tested the resiliency of our proposal against several types of automated attacks: traditional ones; designed ad-hoc for our proposal; and based on machine learning. Compared to the state of the art, our proposal is more user friendly (e.g., only some 35% of the users prefer current solutions, such as text-based CAPTCHAs) and more resilient to automated attacks.Comment: 15 page

gl(n∣m)gl(n|m) color Calogero-Sutherland models and Super Yangian Algebra

A supersymmetric extension of the color Calogero-Sutherland model is considered based on the Yangian $Y(gl(n|m))$. The algebraic structure of the model is discussed in some details. We show that the commuting conserved quantities can be generated from the super-quantum determinant, thus establishing the integrability of the model. In addition, rational limit of the model is studied where the Yangian symmetry degenerates into a super loop algebra.Comment: 15 pages, standard Latex fil

Pole-skipping points in 2D gravity and SYK model

We represent the first investigation of pole-skipping on both the gravity and field theory sides. In contrast to the higher dimensional models, there is no momentum degree of freedom in $(1+1)-$dimensional bulk theory. Thus, we then consider a scalar field mass as our degree of freedom for the pole-skipping phenomenon instead of momentum. The pole-skipping frequencies of the scalar field in 2D gravity are the same as higher dimensional cases: $\omega=-i2\pi Tn$ for positive integer $n$. At each of these frequencies, there is a corresponding pole-skipping mass, so the pole-skipping points exist in the $(\omega,m)$ space. We also compute the pole-skipping points of the SYK model in $(\omega, h)$ space where $h$ is the dimension of the bilinear primary operator. We find that there is a one-to-one correspondence of the pole-skipping points between the JT gravity and the SYK model. To obtain the pole-skipping points, we need to consider the parameter $\epsilon$ related to chemical potential on the horizon of charged JT gravity and the particle-hole asymmetric parameter $\mathcal{E}$ of the complex SYK model as shift parameters. This highlights the $\epsilon-\mathcal{E}$ correspondence in relation to pole-skipping

Z_2 Symmetry Prediction for the Leptonic Dirac CP Phase

Model-independent consequences of applying a generalized hidden horizontal Z_2 symmetry to the neutrino mass matrix are explored. The Dirac CP phase delta_D can be expressed in terms of the three mixing angles as 4 c_a s_a c_s s_s s_x cos delta_D = (s^2_s - c^2_s s^2_x) (c^2_a - s^2_a) where the s_i, c_i are sines and cosines of the atmospheric, solar, and reactor angles. This relation is independent of neutrino masses and whether neutrinos are Dirac- or Majorana-type. Given the present constraints on the angles, delta_D is constrained to be almost maximal, a result which can be explored in experiments such as NOvA and T2K. The Majorana CP phases do not receive any constraint and are thus model-dependent. Also a distribution of theta_x with a lower limit is obtained without specifying delta_D.Comment: 5 pages, 4 figures; Condensed version or PLB with references added; for more details see the previous versio

Probing extra dimensions with higher dimensional black hole analogues?

We propose that extra dimensions might be detected with higher dimensional analogues of black holes. The usual 4-dimensional acoustic(sonic)black hole metric is extended to arbitrary dimensions. The absorption cross-section of Hawking radiation on the brane and in the bulk are calculated in the semiclassical approximation.Comment: 16 pages, 5 figures; Version 2, some references adde

Entanglement of coupled massive scalar field in background of dilaton black hole

The entanglement of the coupled massive scalar field in the spacetime of a Garfinkle-Horowitz-Strominger(GHS) dilaton black hole has been investigated. It is found that the entanglement does not depend on the mass of the particle and the coupling between the scalar field and the gravitational field, but it decreases as the dilaton parameter $D$ increases. It is interesting to note that in the limit of $D\to M$, corresponding to the case of an extreme black hole, the state has no longer distillable entanglement for any state parameter $\alpha$, but the mutual information equals to a nonvanishing minimum value, which indicates that the total correlations consist of classical correlations plus bound entanglement in this limit.Comment: 11 pages, 2 figures, Accepted by PL

Entanglement redistribution in the Schwarzschild spacetime

The effect of Hawking radiation on the redistribution of the entanglement and mutual information in the Schwarzschild spacetime is investigated. Our analysis shows that the physically accessible correlations degrade while the unaccessible correlations increase as the Hawking temperature increases because the initial correlations described by inertial observers are redistributed between all the bipartite modes. It is interesting to note that, in the limit case that the temperature tends to infinity, the accessible mutual information equals to just half of its initial value, and the unaccessible mutual information between mode $A$ and $II$ also equals to the same value.Comment: 11 pages, 3 figures; Submit to PLB on Aug 29, 200

Spin dependent extension of Calogero-Sutherland model through anyon like representations of permutation operators

We consider a $A_{N-1}$ type of spin dependent Calogero-Sutherland model, containing an arbitrary representation of the permutation operators on the combined internal space of all particles, and find that such a model can be solved as easily as its standard $su(M)$ invariant counterpart through the diagonalisation of Dunkl operators. A class of novel representations of the permutation operator $P_{ij}$, which pick up nontrivial phase factors along with interchanging the spins of $i$-th and $j$-th particles, are subsequently constructed. These `anyon like' representations interestingly lead to different variants of spin Calogero-Sutherland model with highly nonlocal interactions. We also explicitly derive some exact eigenfunctions as well as energy eigenvalues of these models and observe that the related degeneracy factors crucially depend on the choice of a few discrete parameters which characterise such anyon like representations.Comment: 25 pages, plain LaTex file, the results of sec.4 are presented in a more explicit way, to appear in Nucl. Phys.