Jun Zhang

TL;DR: The recent GRavitational lEnsing Accuracy Testing (GREAT3) challenge as discussed by the authors was the third in a sequence of challenges for testing methods of inferring weak gravitational lensing shear distortions from simulated galaxy images.

TL;DR: In this paper, the first-crossing distribution of random walks with a moving barrier of arbitrary shape is derived, which can satisfy an integral equation that can be solved by a simple matrix inversion, without the need for Monte Carlo simulations.

TL;DR: In this article, the authors proposed a geometrical approach to constrain dark energy properties, free of any assumptions about the galaxy-mass/mass power spectrum (its shape, amplitude, or growth), which can yield a ~(0.03-0.07)f measurement on the dark energy abundance and equation of state.

TL;DR: In this article, seven Monte Carlo algorithms are compared for constructing merger histories of dark matter haloes, using the extended Press-Schechter (EPS) formalism based on both the spherical and ellipsoidal collapse models, and only the method of Kauffmann & White produces a progenitor mass function that is consistent with the EPS prediction for all look-back redshifts.

TL;DR: In this article, the authors derived an analytic expression for the halo bias in a new theoretical model that incorporates non-Markovian extension of the excursion set theory with a stochastic barrier.