Related papers: Time-dependent fluctuations in the metagalactic ph…
Large-angle fluctuations in the cosmic X-ray background are investigated by a new formalism with a simple model of the X-ray sources. Our method is formulated from the Boltzmann equation and a simple extension of the work by Lahav et al. to…
I discuss fluctuations in the neutral hydrogen (HI) density of the z~2.3 intergalactic medium and show that their relation to cosmic overdensity is strongly scale-dependent. This behaviour arises from a linearized version of the well-known…
Shot noise is an important ingredient to any measurement or theoretical modeling of discrete tracers of the large scale structure. Recent work has shown that the shot noise in the halo power spectrum becomes increasingly sub-Poissonian at…
In gravitational instability models, there is a close relationship between most Lyman-alpha absorption and the matter density along the line of sight. Croft et al. (1997) have shown that it is possible to use this relationship with some…
We study the problem of time-dependent photoionization of low density gaseous nebulae subjected to sudden changes in the intensity of ionizing radiation. To this end, we write a computer code that solves the full time-dependent energy…
We present a method to recover the shape and amplitude of the power spectrum of mass fluctuations, P(k), from observations of the high redshift \lya forest. The method is motivated by the physical picture of the \lya forest that has emerged…
This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer IRAC observations.…
Shot noise is a powerful tool to probe correlations and microscopic transport details that conductance measurements alone cannot reveal. Even in atomic-scale Au devices that are well described by Landauer-B{\"u}ttiker physics, complications…
We investigate the implications of the intergalactic opacity for the evolution of the cosmic UV luminosity density and its sources. Our main constraint is our measurement of the Lya forest opacity at redshifts 2<z<4.2 from 86…
We explore the evolution of the flux power spectrum in the Cosmic Reionization On Computers (CROC) simulations. We find that, contrary to some previous studies, the shape of the flux power spectrum is rather insensitive to the timing of…
We argue that quantum-gravitational fluctuations in the space-time background give the vacuum non-trivial optical properties that include diffusion and consequent uncertainties in the arrival times of photons, causing stochastic…
We examine a model for the variable free-free and neutral hydrogen absorption inferred towards the cores of some compact radio galaxies in which a spatially fluctuating medium drifts in front of the source. We relate the absorption-induced…
The shot noise of spin polarized electrons is shown to be generically dependent upon spin-flip processes. Such a situation represents perhaps the simplest instance where the two-particle character of current fluctuations out of equilibrium…
We use new studies of the cosmic evolution of star-forming galaxies to estimate the production rate of ionizing photons from hot, massive stars at low and intermediate redshifts. The luminosity function of blue galaxies in the Canada-France…
We calibrate here cosmological radiative transfer simulation with ATON/RAMSES with a range of measurements of the Lyman alpha opacity from QSO absorption spectra. We find the Lyman alpha opacity to be very sensitive to the exact timing of…
Interplanetary Scintillation (IPS) induces intensity fluctuations in small angular size astronomical radio sources via the distortive effects of spatially and temporally varying electron density associated with outflows from the Sun. These…
The conventional McCartney model simplifies fog as a scattering medium with space-time invariance, as the time-variant nature of fog is a pure noise for classical optical imaging. In this letter, an opposite finding to traditional idea is…
The 21-cm signal from cosmic dawn and the epoch of reionization (EoR) probes the characteristics of the high redshift galaxy population. Many of the astrophysical properties of galaxies at high redshifts are currently unconstrained due to…
The spatial and temporal noise properties of diffuse radiation is investigated in the context of the cosmic microwave background (CMB), although generic formulae that enable application to any other forms of incoherent light of a prescribed…
Observing finite regions of a bigger system is a common experience, from microscopy to molecular simulations. In the latter especially, there is ongoing interest in predicting thermodynamic properties from tracking fluctuations in finite…