Finite-size-scaling analysis of the XY universality class between two and three dimensions: An application of Novotny's transfer-matrix method

Based on Novotny's transfer-matrix method, we simulated the (stacked) triangular Ising antiferromagnet embedded in the space with the dimensions variable in the range 2 \le d \le 3. Our aim is to investigate the criticality of the XY universality class for 2 \le d \le 3. For that purpose, we employed an extended version of the finite-size-scaling analysis developed by Novotny, who utilized this scheme to survey the Ising criticality (ferromagnet) for 1 \le d \le 3. Diagonalizing the transfer matrix for the system sizes N up to N=17, we calculated the $d$-dependent correlation-length critical exponent \nu(d). Our simulation result \nu(d) appears to interpolate smoothly the known two limiting cases, namely, the KT and d=3 XY universality classes, and the intermediate behavior bears close resemblance to that of the analytical formula via the 1/N-expansion technique. Methodological details including the modifications specific to the present model are reported

Time Dependent Pairing Equations for Seniority One Nuclear Systems

When the time dependent Hartree-Fock-Bogoliubov intrinsic equations of motion are solved in the case of seniority one nuclear systems, the unpaired nucleon remains on the same orbital. The blocking effect hinders the possibility to skip from one orbital to another. This unpleasant feature is by-passed with a new set of pairing time dependent equations that allows the possibility that the unpaired nucleon changes its single-particle level. These equations generalize the time dependent Hartree-Fock-Bogoliubov equations of motion by including the Landau-Zener effect. The derivation of these new equations is presented in details. These equations are applied in the case of a superasymmetric fission process, that is, in order to explain the fine structure the 14C emission from 233Ra. A new version of the Woods-Saxon model extended for two-center potentials is used in this context.Comment: 12 pages, 6 figure

Construction of an isotropic cellular automaton for a reaction-diffusion equation by means of a random walk

We propose a new method to construct an isotropic cellular automaton corresponding to a reaction-diffusion equation. The method consists of replacing the diffusion term and the reaction term of the reaction-diffusion equation with a random walk of microscopic particles and a discrete vector field which defines the time evolution of the particles. The cellular automaton thus obtained can retain isotropy and therefore reproduces the patterns found in the numerical solutions of the reaction-diffusion equation. As a specific example, we apply the method to the Belousov-Zhabotinsky reaction in excitable media

Transfer-matrix approach to the three-dimensional bond percolation: An application of Novotny's formalism

A transfer-matrix simulation scheme for the three-dimensional (d=3) bond percolation is presented. Our scheme is based on Novotny's transfer-matrix formalism, which enables us to consider arbitrary (integral) number of sites N constituting a unit of the transfer-matrix slice even for d=3. Such an arbitrariness allows us to perform systematic finite-size-scaling analysis of the criticality at the percolation threshold. Diagonalizing the transfer matrix for N =4,5,...,10, we obtain an estimate for the correlation-length critical exponent nu = 0.81(5)

Ricardian Equivalence Under Asymmetric Information

Several empirical studies have found that extended household units do not appear to be highly altruistically linked, thereby violating the very premise of the Ricardian Equivalence Hypothesis (REH). This finding has a very strong implication for the effectiveness of fiscal policies that change the allocation of resources between generations. We build a two-sided altruistic-linkage model in which private transfers are made in the presence of two types of shocks: an “observable” shock that is public information (for example, a public redistribution like debt or pay-as-you-go social security) and an “unobservable” shock that is private information (for example, individual wage innovations). Parents and children observe each other’s total income but not each other’s effort level. In the second-best solution, unobservable shocks are only partially shared, whereas, for any utility function satisfying a condition derived herein, observable shocks are fully shared. The model, therefore, can generate the low degree of risk sharing found in previous empirical studies, but REH still holds

SUBARU and e-Merlin observations of NGC3718. Diaries of an SMBH recoil?

NGC3718 is a LINER $L1.9$ galaxy, lying at a distance of about $\sim 17.4$ Mpc away from earth and its similarities with NGC5128 often award it the name "northern Centaurus A". We use high angular resolution ($\sim100$ mas) e-Merlin radio and SUBARU NIR ($\sim170$ mas) data, to take a detailed view of the processes taking place in its central region. In order to preserve some objectivity in our interpretation, we combine our results with literature values and findings from previous studies. Our NIR maps suggest, on one hand, that towards the stellar bulge there are no large scale absorption phenomena caused by the apparent dust lane and, on the other, that there is a significant (local) contribution from hot ($\sim1000$ K) dust to the nuclear NIR emission. The position where this takes place appears to be closer to the offset compact radio emission from our e-Merlin $6$ cm map, lying offset by $\sim4.25$ pc from the center of the underlying stellar bulge. The shape of the radio map suggests the presence of one (or possibly two, forming an X-shape) bipolar structure(s) $\sim1$ ($\sim0.6$) arcsec across, which combined with the balance between the gas and the stellar velocity dispersions and the presence of hard X-ray emission, point towards effects expected by AGN feedback. We also argue that NGC3718 has a "core" in its surface brightness profile, despite the fact that it is a gas-rich galaxy and we discuss its mixed photometric and spectroscopic characteristics. The latter combined with the observed spatial and radio offsets, the relative redshift between the broad and the narrow $H{\mathrm{\alpha}}$ line, the limited star formation activity and AGN feedback, strongly imply the existence of an SMBH recoil. Finally, we discuss a possible interpretation, that could naturally incorporate all these findings into one physically consistent picture.Comment: 18 pages, 18 figures, 3 tables, accepted for publications in A&

Interstellar Extinction Law toward the Galactic Center II: V, J, H, and Ks Bands

We have determined the ratios of total to selective extinction directly from observations in the optical V band and near-infrared J band toward the Galactic center. The OGLE (Optical Gravitational Lensing Experiment) Galactic bulge fields have been observed with the SIRIUS camera on the IRSF telescope, and we obtain A(V)/E(V-J)=1.251+-0.014 and A(J)/E(V-J)=0.225+-0.007. From these ratios, we have derived A(J)/A(V) = 0.188+-0.005; if we combine A(J)/A(V) with the near-infrared extinction ratios obtained by Nishiyama et al. for more reddened fields near the Galactic center, we get A(V) : A(J) : A(H) : A(Ks) = 1 : 0.188 : 0.108 : 0.062, which implies steeply declining extinction toward the longer wavelengths. In particular, it is striking that the Ks band extinction is \approx 1/16 of the visual extinction A(V) much smaller than one tenth of A(V) so far employed.Comment: 8 pages, 7 figures, Accepted for publication in Ap