The Cosmic Web Crystal: Ising model for Large Scale Structures [CL]

http://arxiv.org/abs/2205.05235


If Dark Matter halos possess the gravitational equivalent of an intrinsic magnetic spin, a formal analogy exists between the low redshift behaviour of the Cosmic Web in a flat FLRW background, and a crystal of spins submerged in a thermal reservoir with temperature $T \propto H(t)$. We argue that, within the use of the Bianchi type IX geometry to describe the gravitational collapse of matter inhomogeneities, the spins are nothing but the heritage of its underlying $SU(2)$ symmetry. Therefore, just like electrons in quantum mechanics, these structures may have spin independently from their orbital angular momentum. We explore the phenomenological implications on cosmological scales of a possible late time phase transition of the Cosmic Web towards (the gravitational equivalent of) a ferromagnetic state, described qualitatively using the Ising model in the mean field approximation.

Read this paper on arXiv…

L. Giani and T. Davis
Thu, 12 May 22
7/63

Comments: Essay written for the Gravity Research Foundation 2022 Awards for Essays on Gravitation, awarded Honorable Mention