The first structures were proto-voids formed in the primordial plasma when viscous forces balanced gravitational forces at the Hubble, or horizon, scale of causal connection LH ≡ ct ≈ LSV ≡ (γν/ρG) , where t ≈ 30 000 years was the age of the universe, c the speed of light, γ ≈ 1/t the rate of strain, ν the kinematic viscosity, and LSV Gibson’s 1996 viscous Schwarz scale. The photon viscosity ν ...

Studies of low redshift galaxy clusters suggest the intra-cluster medium (ICM) has experienced non-gravitational heating during formation phase clusters. Using simple phenomenological prescriptions, we simulate effect this preheating nascent ICM in proto-clusters and examine its on Lyman-$\alpha$ (Ly$\alpha$) forest tomographic maps. We analyse a series cosmological zoom-in simulations within f...

Environment is one of the primary drivers galaxy evolution; via multiple mechanisms, it can control critical process transforming galaxies from star forming to quiescent, commonly termed “quenching”. Despite its importance, however, we still do not have a clear view how environmentally-driven quenching proceeds even in most extreme environments: clusters and their progenitor proto-clusters. Rec...