Using state-of-the-art adaptive mesh refinement cosmological hydrodynamic simulations with a spatial resolution of 0.15 h-1kpc on a cosmological volume (20 h-1Mpc), we investigate the sizes of galaxies at z=3 in the standard cold dark matter model where re
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aGalaxySizeProblematz=3:SimulatedGalaxiesAreTooSmallM.RyanJoung1,RenyueCen1,&GregL.Bryan2Received