A Gaussian statistical model of galaxy shapes and radio polarizations yields unbiased, minimum-variance estimators for cosmic shear, intrinsic alignment, and line-of-sight rotation that are accurate to first order.
Second Order Corrections to Weak Lensing by Large-Scale Structure
3 Pith papers cite this work. Polarity classification is still indexing.
abstract
We calculate corrections to the power spectrum predictions of weak lensing by large scale structure due to higher order effects in the gravitational potential. Using a perturbative approach to third order in transverse displacements, we calculate a second order correction to the angular power spectra of E and B mode shear and convergence resulting from dropping the so-called Born approximation, where one integrates along the unperturbed photon path. We also consider a correction to the power spectra from the coupling between lenses at different redshifts. Both effects generate B-mode shear and the latter also causes a net rotation of the background galaxy images. We show all these corrections are at least two orders of magnitude below the convergence or E-mode power and hence relevant only to future ultra high precision measurements. These analytical calculations are consistent with previous numerical estimates and validate the use of current large scale structure weak lensing predictions for cosmological studies and future use of B-modes as a monitor of systematic effects.
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2026 3roles
background 2polarities
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In a pion condensate, photons behave as massive particles and gravitational lensing gains a hadronic correction; the paper derives the modified ray equations and the deflection formula for a pionic-vortex black hole.
ACT DR6 curl lensing yields 2σ bounds Gμ P^{-1} ≤ 3.5×10^{-5} (small-P) and Gμ ≤ 5.0×10^{-5} (P=1), tightened further with Planck 2013 data.
citing papers explorer
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How to augment cosmic shear measurements with radio polarimetry of galaxies?
A Gaussian statistical model of galaxy shapes and radio polarizations yields unbiased, minimum-variance estimators for cosmic shear, intrinsic alignment, and line-of-sight rotation that are accurate to first order.
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Hadronic lensing
In a pion condensate, photons behave as massive particles and gravitational lensing gains a hadronic correction; the paper derives the modified ray equations and the deflection formula for a pionic-vortex black hole.
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Constraints on Cosmic Strings from the Curl-Mode CMB Lensing Power Spectrum measured by ACT DR6
ACT DR6 curl lensing yields 2σ bounds Gμ P^{-1} ≤ 3.5×10^{-5} (small-P) and Gμ ≤ 5.0×10^{-5} (P=1), tightened further with Planck 2013 data.