English
Related papers

Related papers: Cosmic Strings and Weak Gravitational Lensing

200 papers

In the axiverse scenario, a massive scalar field (string axion) forms a cloud around a rotating black hole (BH) by superradiant instability and emits continuous gravitational waves (GWs). We examine constraints on the string axion…

General Relativity and Quantum Cosmology · Physics 2015-06-02 Hirotaka Yoshino , Hideo Kodama

Circular massless cosmic strings which move with the speed of light in the de Sitter universe are described. Construction of the background geometry is based on parabolic isometries of the de Sitter spacetime. Microscopic circular cosmic…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Dmitri V. Fursaev

We investigate the effect of wiggly cosmic strings on the cosmic microwave background radiation anisotropy and matter power spectrum by modifying the string network model used by Albrecht et al.. We employ the wiggly equation of state for…

Astrophysics · Physics 2016-08-25 Levon Pogosian , Tanmay Vachaspati

Current theories of structure formation predict specific density profiles of galaxy dark matter haloes, and with weak gravitational lensing we can probe these profiles on several scales. On small scales, higher-order shape distortions known…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Malin Velander , Konrad Kuijken , Tim Schrabback

This chapter provides a comprehensive overview of weak gravitational lensing and its current applications in cosmology. We begin by introducing the fundamental concepts of gravitational lensing and derive the key equations for the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-06 J. Prat , D. Bacon

We investigate the potential of weak gravitational lensing maps to differentiate between distinct cosmological models, considering cosmic variance due to a limited map extension and the presence of noise. We introduce a measure of the…

Astrophysics · Physics 2009-11-07 Antonio Guimarães

We study the optical appearance of a thin accretion disk around a Schwarzschild black hole pierced by a cosmic string with a semi-analytic method of Luminet [11]. Direct and secondary images with different parameters observed by a distant…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Changqing Liu , Li Tang , Jiliang Jing

We consider the prospects for detecting weak gravitational lensing by underdensities (voids) in the large-scale matter distribution. We derive the basic expressions for magnification and distortion by spherical voids. Clustering of the…

Astrophysics · Physics 2009-09-25 Luca Amendola , Joshua A. Frieman , Ioav Waga

Cosmic strings are generic cosmological predictions of many extensions of the Standard Model of particle physics, such as a $U(1)^\prime$ symmetry breaking phase transition in the early universe or remnants of superstring theory. Unlike…

High Energy Physics - Phenomenology · Physics 2018-06-13 Yanou Cui , Marek Lewicki , David E. Morrissey , James D. Wells

The wealth of incoming and future cosmological observations will allow us to map out the structure and evolution of the observable universe to an unprecedented level of precision. Among these observations is the weak gravitational lensing…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 M. A. Troxel , Mustapha Ishak

The mean spectrum and burst statistics of gravitational waves produced by a cosmological population of cosmic string loops are estimated using analytic approximations, calibrated with earlier simulations. Formulas are derived showing the…

Astrophysics · Physics 2009-11-11 Craig J. Hogan

The time-dependent metric of a cosmic string leads to an effective interaction between the string and photons - the "gravitational Aharonov-Bohm" effect -- and causes cosmic strings to emit light. We evaluate the radiation of pairs of…

High Energy Physics - Theory · Physics 2011-03-23 Daniele A. Steer , Tanmay Vachaspati

Cosmic strings, theoretical one-dimensional topological defects from the early universe, provide a valuable opportunity for exploring dark matter (DM) production and gravitational wave (GW) emission. Our study investigates the production of…

High Energy Physics - Phenomenology · Physics 2024-09-25 Hanyu Cheng , Luca Visinelli

The interaction of a cosmic string and a maximally charged dilatonic black hole is studied in the low-velocity limit. In particular, the string-black hole scattering at a low velocity is investigated.

General Relativity and Quantum Cosmology · Physics 2014-11-17 Kiyoshi Shiraishi

Correlated red noise recently reported from pulsar timing observations may be an indication of stochastic gravitational waves emitted by cosmic strings that formed during a primordial phase transition near the Grand Unification energy…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-07 Huangyu Xiao , Liang Dai , Matthew McQuinn

We have searched 4.5 square degrees of archival HST/ACS images for cosmic strings, identifying close pairs of similar, faint galaxies and selecting groups whose alignment is consistent with gravitational lensing by a long, straight string.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Eric Morganson , Phil Marshall , Tommaso Treu , Tim Schrabback , Roger D. Blandford

Weak lensing is the distortion (polarization) of images of distant objects, such as high redshift galaxies, by gravitational fields in the limit where the distortion is small. Gravitational potential fluctuations due to large scale…

Astrophysics · Physics 2015-06-24 Jens Verner Villumsen

The developments summarized with the name ``weak gravitational lensing'' have led to exciting possibilities to study the (statistical properties of the) dark matter distribution in the Universe. Concentrating on those aspects which require…

Astrophysics · Physics 2007-05-23 Peter Schneider , Jean-Paul Kneib

The exact metric around a wiggly cosmic string is found by modifying the energy momentum-tensor of a straight infinitely thin cosmic string to include an electric current along the symmetry axis.

General Relativity and Quantum Cosmology · Physics 2015-06-25 N. Ozdemir

Line discontinuities in cosmic microwave background anisotropy maps are a distinctive prediction of models with cosmic strings. These signatures are visible in anisotropy maps with good angular resolution and should be identifiable using…

Astrophysics · Physics 2009-06-23 Stephen Amsel , Joshua Berger , Robert H. Brandenberger