English
Related papers

Related papers: Quantifying cosmic variance

200 papers

Upcoming weak lensing surveys will survey large cosmological volumes to measure the growth of cosmological structure with time and thereby constrain dark energy. One major systematic uncertainty in this process is the calibration of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Arun Kannawadi , Rachel Mandelbaum , Claire Lackner

Deep pencil beam surveys (<1 deg^2) are of fundamental importance for studying the high-redshift universe. However, inferences about galaxy population properties are in practice limited by 'cosmic variance'. This is the uncertainty in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Benjamin P. Moster , Rachel S. Somerville , Jeffrey A. Newman , Hans-Walter Rix

In the coming decade, a new generation of telescopes, including JWST and WFIRST, will probe the period of the formation of first galaxies and quasars, and open up the last frontier for structure formation. Recent simulations as well as…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 Aklant K. Bhowmick , Rachel S. Somerville , Tiziana DiMatteo , Stephen Wilkins , Yu Feng , Ananth Tenneti

We present a cosmic shear analysis of the 100 square degree weak lensing survey, combining data from the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys. Spanning ~100 square degrees, with a median source redshift z~0.78, this combined…

We study cosmic variance in deep high redshift surveys and its influence on the determination of the luminosity function for high redshift galaxies. For several survey geometries relevant for HST and JWST instruments, we characterize the…

Astrophysics · Physics 2020-07-28 M. Trenti , M. Stiavelli

The discovery of extremely luminous galaxies at ultra-high redshifts ($z\gtrsim 8$) has challenged galaxy formation models. Most analyses of this tension have not accounted for the variance due to field-to-field clustering, which causes the…

Astrophysics of Galaxies · Physics 2025-04-04 Christian Kragh Jespersen , Charles L. Steinhardt , Rachel S. Somerville , Christopher C. Lovell

Cosmic variance is the uncertainty in observational estimates of the volume density of extragalactic objects such as galaxies or quasars arising from the underlying large-scale density fluctuations. This is often a significant source of…

At the core of the standard cosmological model lies the assumption that the redshift of distant galaxies is independent of photon wavelength. This invariance of cosmological redshift with wavelength is routinely found in all galaxy spectra…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-20 I. Ferreras , I. Trujillo

The results from weak gravitational lensing analyses are subject to a cosmic variance error term that has previously been estimated assuming Gaussian statistics. In this letter we address the issue of estimating cosmic variance errors for…

Intrinsic variations of the projected density profiles of clusters of galaxies at fixed mass are a source of uncertainty for cluster weak lensing. We present a semi-analytical model to account for this effect, based on a combination of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 D. Gruen , S. Seitz , M. R. Becker , O. Friedrich , A. Mana

There is an approximately 9% discrepancy, corresponding to 2.4sigma, between two independent constraints on the expansion rate of the universe: one indirectly arising from the cosmic microwave background and baryon acoustic oscillations,…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 Valerio Marra , Luca Amendola , Ignacy Sawicki , Wessel Valkenburg

Despite its fundamental importance in cosmology, there have been very few straight-forward tests of the cosmological principle. Such tests are especially timely because of the hemispherical asymmetry in the cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-19 Michael J. Longo

Using the method of searching for arbitrary shaped voids in the distribution of volume-limited samples of galaxies from the DR5 SDSS survey, we have identified voids and investigated their characteristics and the change in these…

Astrophysics · Physics 2008-11-26 Anton V. Tikhonov

Cosmic variance is the intrinsic scatter in the number density of galaxies due to fluctuations in the large-scale dark matter density field. In this work, we present a simple analytic model of cosmic variance in the high redshift Universe…

Astrophysics of Galaxies · Physics 2020-10-21 A. C. Trapp , Steven R. Furlanetto

Since the cosmic peculiar velocity field depends on small wave-number modes strongly, we cannot probe its universal properties unless we observe a sufficiently large region. We calculate the expected deviation (sample variance) of the…

Astrophysics · Physics 2009-10-30 Naoki Seto , Jun'ichi Yokoyama

According to the cosmological principle, galaxy cluster sizes and cluster densities, when averaged over sufficiently large volumes of space, are expected to be constant everywhere, except for a slow variation with look-back time (redshift).…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-03 Michael J. Longo

Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or…

The relative cosmic variance ($\sigma_v$) is a fundamental source of uncertainty in pencil-beam surveys and, as a particular case of count-in-cell statistics, can be used to estimate the bias between galaxies and their underlying…

Recent deep millimeter-wave surveys attempt to measure the carbon monoxide (CO) luminosity function and mean molecular gas density through blind detections of CO emission lines. While the cosmic star formation rate density is now…

Astrophysics of Galaxies · Physics 2021-01-19 Ryan P. Keenan , Daniel P. Marrone , Garrett K. Keating

Cosmic variance introduces significant uncertainties into galaxy number density properties when surveying the high-z Universe with a small volume, such uncertainties produce the field-to-field variance of galaxy number $\sigma_{g}$ in…

‹ Prev 1 2 3 10 Next ›