175 citations · 1.3k across the 24 of their papers we have counts for
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Handbook for the GREAT08 Challenge: An image analysis competition for cosmological lensing
Sarah Bridle, John Shawe-Taylor, Adam Amara +35
The GRavitational lEnsing Accuracy Testing 2008 (GREAT08) Challenge focuses on a problem that is of crucial importance for future observations in cosmology. The shapes of distant g…
Lensing signals in the Hubble Ultra-Deep Field using all 2nd order shape deformations
John Irwin, Marina Shmakova, Jay Anderson
The long exposure times of the HST Ultra-Deep Field plus the use of an empirically derived position-dependent PSF, have enabled us to measure a cardioid/displacement distortion map…
Observation of small scale structure using sextupole lensing
John Irwin, Marina Shmakova
Weak gravitational lensing seeks to determine shear by measuring induced quadrupole (elliptical) shapes in background galaxy images. Small impact parameter (a few kpc) gravitationa…
Current Observational Constraints on Cosmic Doomsday
Yun Wang, Jan Michael Kratochvil, Andrei Linde +1
In a broad class of dark energy models, the universe may collapse within a finite time t_c. Here we study a representative model of dark energy with a linear potential, V(ϕ)=V_0(1+…
Testing the Cosmological Constant as a Candidate for Dark Energy
Jan Kratochvil, Andrei Linde, Eric V. Linder +1
It may be difficult to single out the best model of dark energy on the basis of the existing and planned cosmological observations, because many different models can lead to simila…
Observations of cluster substructure using weakly lensed sextupole moments
John Irwin, Marina Shmakova
Since dark matter clusters and groups may have substructure, we have examined the sextupole content of Hubble images looking for a curvature signature in background galaxies that w…
Observational Bounds on Cosmic Doomsday
Renata Kallosh, Jan Kratochvil, Andrei Linde +2
Recently it was found, in a broad class of models, that the dark energy density may change its sign during the evolution of the universe. This may lead to a global collapse of the…