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Accurately computing weak lensing convergence
- Publication Year :
- 2018
- Publisher :
- arXiv, 2018.
-
Abstract
- Weak lensing will play an important role in future cosmological surveys, including e.g. Euclid and SKA. Sufficiently accurate theoretical predictions are important for correctly interpreting these surveys and hence for extracting correct cosmological parameter estimations. We quantify for the first time in a relativistic setting how many post-Born and lens-lens coupling corrections are required for sub-percent accuracy of the theoretical weak lensing convergence for $z\le 2$ (the primary weak lensing range for Euclid and SKA). We do this by ray-tracing through a fully relativistic exact solution of the Einstein Field Equations which consists of randomly packed mass-compensated underdensities of realistic amplitudes. We find that including lens-lens coupling terms and post-Born corrections up to second and third order respectively is sufficient for sub-percent accuracy of the convergence along $94\%$ of the studied light rays. We also find that a significant percentage of the studied rays have post-Born corrections of size over $10\%$ of the usual gravitational convergence, $\kappa^{(1)}$, and several rays even have post-Born corrections several times the size of $\kappa^{(1)}$ at $z = 2$.<br />Comment: 5 pages, 4 figures. v2: More data added with figures and text changed appropriately. Overall results unchanged. v3: Significant changes to presentation to match published version. Overall results unchanged
- Subjects :
- Cosmology and Nongalactic Astrophysics (astro-ph.CO)
FOS: Physical sciences
Astrophysics
Astrophysics::Cosmology and Extragalactic Astrophysics
General Relativity and Quantum Cosmology (gr-qc)
114 Physical sciences
01 natural sciences
General Relativity and Quantum Cosmology
Gravitation
Theoretical physics
gravitational lensing: weak
0103 physical sciences
Convergence (routing)
010303 astronomy & astrophysics
Weak gravitational lensing
Physics
010308 nuclear & particles physics
Astronomy and Astrophysics
Coupling (probability)
Ray
Amplitude
Exact solutions in general relativity
Space and Planetary Science
large-scale structure of Universe
cosmology: observations
Einstein field equations
Astrophysics - Cosmology and Nongalactic Astrophysics
Subjects
Details
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....413bf597a1dd62f125f7ac1194f353fb
- Full Text :
- https://doi.org/10.48550/arxiv.1812.00861