The Anisotropic Two-Point Correlation Functions of the Nonlinear Traceless Tidal Field in the Principal-Axis Frame

Galaxies on the largest scales of the Universe are observed to be embedded in the filamentary cosmic web which is shaped by the nonlinear tidal field. As an efficient tool to quantitatively describe the statistics of this cosmic web, we present the anisotropic two-point correlation functions of the nonlinear traceless tidal field in the principal-axis frame, which are measured using numerical data from an N-body simulation. We show that both of the nonlinear density and traceless tidal fields are more strongly correlated along the directions perpendicular to the eigenvectors associated with the largest eigenvalues of the local tidal field. The correlation length scale of the traceless tidal field is found to be ~20 Mpc/h, which is much larger than that of the density field ~5 Mpc/h. We also provide analytic fitting formulae for the anisotropic correlation functions of the traceless tidal field, which turn out to be in excellent agreement with the numerical results. We expect that our numerical results and analytic formula are useful to disentangle cosmological information from the filamentary network of the large-scale structures.Comment: ApJ in press, accepted version, minor changes, discussion improve

Massless Monopoles and Multipronged Strings

We investigate the role of massless magnetic monopoles in the N=4 supersymmetric Yang-Mills Higgs theories. They can appear naturally in the 1/4-BPS dyonic configurations associated with multi-pronged string configurations. Massless magnetic monopoles can carry nonabelian electric charge when their associated gauge symmetry is unbroken. Surprisingly, massless monopoles can also appear even when the gauge symmetry is broken to abelian subgroups.Comment: 10 pages, LaTex file, more comments added. (To appear in Phys. Lett. B

Regge Closed String Scattering and its Implication on Fixed angle Closed String Scattering

We calculate the complete closed string high energy scattering amplitudes (HSA) in the Regge regime for arbitrary mass levels. As an application, we deduce the complete ratios among closed string HSA in the fixed angle regime by using Stirling number identities. These results are in contrast with the incomplete set of closed string HSA in the fixed angle regime calculated previously. The complete forms of the fixed angle amplitudes, and hence the ratios, were not calculable previously without the input of zero-norm state calculation. This is mainly due to the lack of saddle point in the fixed angle closed string calculation.Comment: 10 pages. v2: typos correcte

Chart-driven Connectionist Categorial Parsing of Spoken Korean

While most of the speech and natural language systems which were developed for English and other Indo-European languages neglect the morphological processing and integrate speech and natural language at the word level, for the agglutinative languages such as Korean and Japanese, the morphological processing plays a major role in the language processing since these languages have very complex morphological phenomena and relatively simple syntactic functionality. Obviously degenerated morphological processing limits the usable vocabulary size for the system and word-level dictionary results in exponential explosion in the number of dictionary entries. For the agglutinative languages, we need sub-word level integration which leaves rooms for general morphological processing. In this paper, we developed a phoneme-level integration model of speech and linguistic processings through general morphological analysis for agglutinative languages and a efficient parsing scheme for that integration. Korean is modeled lexically based on the categorial grammar formalism with unordered argument and suppressed category extensions, and chart-driven connectionist parsing method is introduced.Comment: 6 pages, Postscript file, Proceedings of ICCPOL'9

On the Intrinsic Alignments of the Late-Type Spiral Galaxies from the Sloan Digital Sky Survey Data Release 7

A robust detection of the tidally induced intrinsic alignments of the late-type spiral galaxies with high statistical significance is reported. From the spectroscopic galaxy sample of SDSS DR7 compiled by Huertas-Company et al. which lists each galaxy's probabilities of being in five Hubble types, P(E),P(Ell), P(S0),P(Sab), P(Scd), we select the nearby large late-type spiral galaxies which have redshifts of 0=0.5 and angular sizes of D>=7.92 arcsec. The spin axes of the selected nearby large late-type spiral galaxies are determined up to the two-fold ambiguity with the help of the circular thin-disk approximation and their spatial correlations are measured as a function of the separation distance r. A clear signal of the intrinsic correlation as high as 3.4 sigma and 2.4 sigma is found at the separation distance of r~1Mpc/h and r~2Mpc/h, respectively. The comparison of this observational results with the analytic model based on the tidal torque theory reveals that the spin correlation function for the late-type spiral galaxies follow the quadratic scaling of the linear density correlation and that the intrinsic correlations of the galaxy spin axes are stronger than that of the underlying dark halos. We investigate a local density dependence of the galaxy spin correlations and found that the correlations are stronger for the galaxies located in dense regions having more than 10 neighbors within 2Mpc/h. We also attempt to measure a luminosity dependence of the galaxy spin correlations, but find that it is impossible with our magnitude-split samples to disentangle a luminosity from a redshift dependence. We provide the physical explanations for these observational results and also discuss the effects of possible residual systematics on the results.Comment: Accepted for publication in ApJ, revised version, The angular size cut on the late-type spiral galaxies is additionally applied, the quadractic scaling with the linear density field is found to work better when the angular size cut is applied. Those galaxies located in denser regions are found to be strongly correlate

Stringy Symmetries and Their High-energy Limits

We derive stringy symmetries with conserved charges of arbitrarily high spins from the decoupling of two types of zero-norm states in the old covariant first quantized (OCFQ) spectrum of open bosonic string. These symmetries are valid to all energy and all loop orders in string perturbation theory. The high-energy limit of these stringy symmetries can then be used to fix the proportionality constants between scattering amplitudes of different string states algebraically without referring to Gross and Mende's saddle point calculation of high-energy string-loop amplitudes. These proportionality constants are, as conjectured by Gross, independent of the scattering angle and the order of string perturbation theory. However, we also discover some new nonzero components of high-energy amplitudes not found previously by Gross and Manes. These components are essential to preserve massive gauge invariances or decouple massive zero-norm states of string theory. A set of massive scattering amplitudes and their high energy limit are calculated explicitly to justify our results.Comment: 10 pages. A corrected version of hep-th/0303012. Final version to appear in Phys. Lett.

Upscaling Polymer Flooding in Heterogeneous Reservoirs

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Surface r Modes and Burst Oscillations of Neutron Stars

We study the $r$-modes propagating in steadily mass accreting, nuclear burning, and geometrically thin envelopes on the surface of rotating neutron stars. For the modal analysis, we construct the envelope models which are fully radiaitive or have a convective region. As the angular rotation frequency $\Omega$ is increased, the oscillation frequency $\omega$ of the $r$-modes in the thin envelopes deviates appreciably from the asymptotic frequency $\omega=2m\Omega/l^\prime(l^\prime+1)$ defined in the limit of $\Omega\to 0$, where $\omega$ is the frequency observed in the corotating frame of the star, and $m$ and $l^\prime$ are the indices of the spherical harmonic function $Y_{l^\prime}^m$ representing the angular dependence of the modes. We find that the fundamental $r$-modes in the convective models are destabilized by strong nuclear burning in the convective region. Because of excessive heating by nuclear buring, the corotating-frame oscillation frequency $\omega$ of the $r$-modes in the convective models becomes larger, and hence the inertial-frame oscillation frequency $|\sigma|$ becomes smaller, than those of the corresopnding $r$-modes in the radiative models, where $\sigma=\omega-m\Omega$ is negative for the $r$-modes of positive $m$. We find that the relative frequency change $f=-(\sigma_{conv}-\sigma_{rad})/\sigma_{rad}$ is always positive and becomes less than $\sim$0.01 for the fundamental $r$-modes of $l^\prime>|m|+1$ at $|\sigma_{rad}|/2\pi\sim$300Hz for $m=1$ or at $|\sigma_{rad}|/2\pi\sim$600Hz for $m=2$, where $\sigma_{conv}$ and $\sigma_{rad}$ denote the oscillation frequencies for the convective and the radiative envelope models, respectively.Comment: 20 pages, 12 figure