English
Related papers

Related papers: Weak lensing generated by vector perturbations and…

200 papers

Cosmological defects result from cosmological phase transitions in the early Universe and the dynamics reflects their symmetry-breaking mechanisms. These cosmological defects may be probed through weak lensing effects because they interact…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Shohei Saga , Kouichirou Horiguchi , Kiyotomo Ichiki

We study the deflection of light in the background of a "wiggly" cosmic string, and investigate whether it is possible to detect cosmic strings by means of weak gravitational lensing. For straight strings without small-scale structure there…

Astrophysics · Physics 2007-10-11 Sergei Dyda , Robert H. Brandenberger

We present constraints on a cosmic string network with a measurement of weak gravitational lensing from CMB temperature map. The cosmic string network between observer and last scattering surface of CMB photons generates vector and/or…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Toshiya Namikawa , Daisuke Yamauchi , Atsushi Taruya

Vector perturbations sourced by topological defects can generate rotations in the lensing of background galaxies. This is a potential smoking gun for the existence of defects since rotation generates a curl-like component in the weak…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Daniel B. Thomas , Carlo R. Contaldi , Joao Magueijo

The vector mode of cosmological perturbation theory imprints characteristic signals on the weak lensing signals such as curl- and B-modes which are never imprinted by the scalar mode. However, the vector mode is neglected in the standard…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Shohei Saga , Daisuke Yamauchi , Kiyotomo Ichiki

Weak lensing has become an increasingly important tool in cosmology and the use of galaxy shapes to measure cosmic shear has become routine. The weak-lensing distortion tensor contains two other effects in addition to the two components of…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Daniel B. Thomas , Lee Whittaker , Stefano Camera , Michael L. Brown

We study the effect of weak lensing by cosmic (super-)strings on the higher-order statistics of the cosmic microwave background (CMB). A cosmic string segment is expected to cause weak lensing as well as an integrated Sachs-Wolfe (ISW)…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-22 Daisuke Yamauchi , Yuuiti Sendouda , Keitaro Takahashi

We present a framework for detecting gravitational-wave signals lensed by cosmic strings (CSs), addressing a key gap in current searches. CSs, whose detection would provide a unique probe of high-energy physics and the early Universe,…

General Relativity and Quantum Cosmology · Physics 2026-02-25 Oleg Bulashenko , Nino Villanueva , Roberto Bada Nerin , José A. Font

We report a detection of the coherent distortion of faint galaxies arising from gravitational lensing by foreground structures. This ``cosmic shear'' is potentially the most direct measure of the mass power spectrum, as it is unaffected by…

Astrophysics · Physics 2011-05-05 David Bacon , Alexandre Refregier , Richard Ellis

We measure seeing-corrected ellipticities for 2 x 10^6 galaxies with magnitude R<23 in 12 widely separated fields totalling 75 deg^2 of sky. At angular scales >30\arcmin, ellipticity correlations are detected at high significance and…

Astrophysics · Physics 2015-06-24 M. Jarvis , G. Bernstein , B. Jain , P. Fischer , D. Smith , J. A. Tyson , D. Wittman

Cosmic strings are generically predicted in many extensions of the Standard Model of particle physics. We propose a new avenue for detecting cosmic strings through their effect on the filamentary structure in the cosmic web. Using…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 M. A. Fernandez , Simeon Bird , Yanou Cui

Cosmic superstrings are produced towards the end of the brane inflation. If the string tension is low enough, loops tend to be relatively long-lived. The resultant string network is expected to contain many loops which are smaller than…

Astrophysics · Physics 2007-09-10 David F. Chernoff , S. -H. Henry Tye

We consider the gravitational lensing produced by long cosmic strings formed in a GUT scale phase transition. We derive a formula for the deflection of photons which pass near the strings that reduces to an integral over the light cone…

Astrophysics · Physics 2009-10-30 Andrew A. de Laix

Cosmic string wakes produce direct B-mode polarization at leading order in cosmological perturbation theory, as worked out in a previous publication \cite{BDH} in the case of a single string wake. Here we compute the angular power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-28 Robert Brandenberger , Nick Park , Grant Salton

We study the effect of weak lensing by cosmic (super-)strings on the anisotropies of cosmic microwave background (CMB). In developing a method to calculate the lensing convergence field due to strings, and thereby temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Daisuke Yamauchi , Keitaro Takahashi , Yuuiti Sendouda , Chul-Moon Yoo

We discuss the future detectability of gravitational-wave induced lensing from high-sensitivity cosmic microwave background (CMB) experiments. Gravitational waves can induce a rotational component of the weak-lensing deflection angle,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-11 Toshiya Namikawa , Daisuke Yamauchi , Atsushi Taruya

We explore the use of random forest and gradient boosting, two powerful tree-based machine learning algorithms, for the detection of cosmic strings in maps of the cosmic microwave background (CMB), through their unique Gott-Kaiser-Stebbins…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-12 A. Vafaei Sadr , M. Farhang , S. M. S. Movahed , B. Bassett , M. Kunz

In a recent publication, we used the data from WMAP and SDSS to constrain the primordial perturbations and to predict the B-mode polarization sourced by cosmic string networks. We have been alerted by A. Slosar to the existence of errors in…

Astrophysics · Physics 2007-05-23 Levon Pogosian , Ira Wasserman , Mark Wyman

Scaling networks of cosmic defects, such as strings and textures, actively generate scalar, vector and tensor metric perturbations throughout the history of the universe. In particular, {\em vector} modes sourced by defects are an efficient…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Adam Moss , Levon Pogosian

Cosmic strings are important remnants of early-Universe phase transitions. We show that they can be probed by Gravitational Waves (GWs) from compact binary mergers. If such chirping GW passes by a cosmic string, it is gravitationally lensed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-05 Sunghoon Jung , TaeHun Kim
‹ Prev 1 2 3 10 Next ›