Stochastic fluctuations and structure formation in the Universe.
It is shown that the evolution of the density perturbations during certain eras of substantial entropy generation in the Universe can be described in the scheme of the Kardar-Parizi-Zhang equation. Therefore, the influence on cosmological structure formation by stochastic forces arising from various dissipations can be studied through the universal characteristics of surface growth in [ital d]=3+1 dimensions. We identify eras of strong stochastic fluctuations and describe dynamically how these other dissipative sources of noise, besides initial (inflationary) quantum fluctuations, generate seeds of density perturbation with power law spectrum, including the Harrison-Zeldovich spectrum.

title: The Local Power Spectrum and Correlation Hierarchy of the Cosmic Mass Field
abstract: We analyze the power spectrum of a QSO's Lyα-transmitted flux in the discrete wavelet transform (DWT) representation. Although the mean DWT power spectrum is consistent with its counterpart in Fourier representation, the spatial distribution of the local power varies greatly; i.e., the local DWT power spectra show remarkably spiky structures on small scales. To measure these spiky features, we introduce the quantities roughness of the local power spectrum and correlation between spikes on different scales. We then test the predictions made by the correlation hierarchy model on the roughness and the scale-scale correlations of the local power spectrum. Using the Lyα-transmitted flux of the QSO HS 1700, we find that the underlying cosmic mass field of the transmitted flux at redshift around z 2.2 can be described by the hierarchical clustering model on physical scales from 2.5 h-1 Mpc to a few tens h-1 kpc in an Einstein-de Sitter universe. However, the nonlinear features of the clustering show differences on different scale ranges: (1) On physical scales larger than ~1.3 h-1 Mpc, the field is almost Gaussian. (2) On scales 1.3-0.3 h-1 Mpc, the field is consistent with the correlation hierarchy with a constant value for the coefficient Q4. (3) On scales less than 300 h-1 kpc, the field is no longer Gaussian but essentially intermittent. In this case, the field can still be fitted by the correlation hierarchy, but the coefficient, Q4, should be scale dependent. These three points are strongly supported by the following result: the scale dependencies of Q4 given by two statistically independent measures, i.e., Q by roughness and Q by scale-scale correlation, are the same in the entire scale range considered.

title: Environmental Effect on the Associations of Background Quasars with Foreground Objects. II. Numerical Simulations
abstract: Using numerical simulations of cluster formation in the standard cold dark matter (CDM) model and in a low-density, flat CDM model with a cosmological constant, we investigate the gravitational lensing explanation for the reported associations between background quasars and foreground clusters. Under the thin-lens approximation and the unaffected-background hypothesis, we show that the recently detected quasar overdensity around clusters of galaxies on scales of ~10' cannot be interpreted as a result of gravitational lensing by cluster matter or by their environmental and projected matter along the line of sight, which is consistent with the analytical result based on the observed cluster and galaxy correlations. It appears very unlikely that uncertainties in the modeling of the gravitational lensing can account for the disagreement between the theoretical predictions and the observations. We conclude that either the detected signal of the quasar-cluster associations is a statistical fluke or the associations are generated by mechanisms other than the magnification bias.

title: EVIDENCE FOR SCALE-SCALE CORRELATIONS IN THE COSMIC MICROWAVE BACKGROUND RADIATION
abstract: We perform a discrete wavelet analysis of the Cosmic Background Explorer differential microwave radiometer (DMR) 4-yr sky maps and find a significant scale-scale correlation on angular scales from about 11\ifmmode^\circ\else\textdegree\fi{} to 22\ifmmode^\circ\else\textdegree\fi{}, only in the DMR face centered on the north galactic pole. This non-Gaussian signature does not arise either from the known foregrounds or the correlated noise maps, nor is it consistent with upper limits on the residual systematic errors in the DMR maps. Either the scale-scale correlations are caused by an unknown foreground contaminate or systematic errors on angular scales as large as 22\ifmmode^\circ\else\textdegree\fi{}, or the standard inflation plus cold dark matter paradigm is ruled out at the $g99%$ confidence level.

title: Time-dependent correlations of inflationary perturbations
abstract: We show that if the primordial classical perturbations were generated by the gravitational particle creation during inflation, and followed by an evolution of quantum-to-classical transition, the time-dependent correlation of these perturbations is long-tailed with a correlation time larger than the Hubble time. Consequently, the inflationary perturbations are locally scale-scale correlated. Hence, the interaction of the fields during inflation can be explored via the detection of the local scale-scale correlation of the CMB fluctuations.

title: A Statistical Comparison of Cluster Mass Estimates from Optical/X-Ray Observations and Gravitational Lensing
abstract: We present a statistical comparison of three different estimates of cluster mass, namely, the dynamical masses obtained from the velocity dispersion of optical galaxies, the X-ray masses measured from the temperature of X-ray-emitting gas under the assumption of isothermal hydrostatic equilibrium, and the gravitational lensing masses derived from the strong/weak distortions of background galaxy images. Using a sample of 29 lensing clusters available in literature, we show that the dynamical masses are in agreement with the gravitational lensing masses while the X-ray method has systematically underestimated cluster masses by a factor of 2-3 as compared with the others. These results imply that galaxies indeed trace the gravitational potential of their clusters and that there is no bias between the velocities of the dark matter particles and the galaxies in clusters. The X-ray cluster mass discrepancy probably arises from the simplification in the models for the X-ray gas distribution and dynamical evolution.

title: Studies of xi (2230) in J/ psi radiative decays.

title: Measurement of the mass of the tau lepton.
abstract: Author(s): Bai, JZ; Bardon, O; Becker-Szendy, RA; Blum, I; Breakstone, A; Burnett, T; Chen, GP; Chen, HF |  A data-driven energy scan in the immediate vicinity of the τ pair production threshold has been performed using the Beijing Spectrometer at the Beijing Electron-Positron Collider. Approximately 5pb-1of data, distributed over 12 scan points, have been collected. A previous mass value for the τ lepton, obtained using only the eµ final state, has been published. In this paper, the final BES result on the mass measurement is presented. The analysis is based on the combined data from the ee, eµ, eh, µµ, µh, and hh final states, where h denotes a charged Π or K. A maximum likelihood fit to the τ pair production cross section data yields the value mT=1776.96-0.21-0.17+0.18+0.25.