Naoshi Sugiyama

Small scale cosmological perturbations: An Analytic approach

Through analytic techniques verified by numerical calculations, we establish general relations between the matter and cosmic microwave background (CMB) power spectra and their dependence on parameters on small scales. Fluctuations in the CMB, baryons, cold dark matter (CDM), and neutrinos receive a boost at horizon crossing. Baryon drag on the photons causes alternating acoustic peak heights in the CMB and is uncovered in its bare form under the photon diffusion scale. Decoupling of the photons at last scattering and of the baryons at the end of the Compton drag epoch freezes the diffusion-damped acoustic oscillations into the CMB and matter power spectra at different scales. We determine the dependence of the respective acoustic amplitudes and damping lengths on fundamental cosmological parameters. The baryonic oscillations, enhanced by the velocity overshoot effect, compete with CDM fluctuations in the present matter power spectrum. We present new exact analytic solutions for the cold dark matter fluctuations in the presence of a growth-inhibiting radiation and baryon background. Combined with the acoustic contributions and baryonic infall into CDM potential wells, this provides a highly accurate analytic form of the small-scale transfer function in the general case.

Cosmology with x-matter

Motivated by the possibility of

Non-uniform reionization by galaxies and its effect on the cosmic microwave background

H_0t_0 > 1

COBE-DMR-normalized Open Cold Dark Matter Cosmogonies

where

Limits on neutrino mass from cosmic structure formation

H_0

Cosmic Microwave Background Anisotropy Constraints on Open and Flat-Λ Cold Dark Matter Cosmogonies from UCSB South Pole, ARGO, MAX, White Dish, and SuZIE Data

and

Cosmic Microwave Background Anisotropy Correlation Function and Topology from Simulated Maps for MAP

t_0

Effect of Void Network on Cosmic Microwave Background Anisotropy

are the Hubble parameter and the age of the universe, respectively, we investigate the cosmology including x-matter. x-matter is expressed by the equation of state

EVOLUTION OF SMALL-SCALE COSMOLOGICAL BARYON PERTURBATIONS AND MATTER TRANSFER FUNCTIONS

p_x=w_0\rho_{x0} + c_s^2(\rho_x-\rho_{x0})

Double inflation in supergravity and the large scale structure

, where