The Baryonic Tully-Fisher Relationship: A consequence of Newtonian Gravitation acting in a hierarchical Universe

Abstract

It has been reported that the application of convolutional neural-network techniques to infer the Dark Matter distribution in the local IGM has revealed how it follows the hierarchical distribution of galaxies in the locality, rather than exhibiting homogeneity. This result makes it natural to consider the possibility that, on scales at least as big as $20 \sim 30\,Mpc$, the distribution of all material comprising the local IGM is hierarchically distributed. Given this possibility, any model of galaxy formation must then involve a process in which all of the hierarchically distributed material $M_0$ within a sphere $R_0$ coalesces about a unique center so that hierarchical symmetry is broken on the scale $(M_0,R_0)$. In the particular case of the hierarchical distribution being quasi-fractal $D \approx 2$ in the local cosmos then, for circular velocity $V_0$ on $R_0$, the scaling relation $V_0^4 \sim M_0$ emerges automatically when the condition that such a galaxy formation process must be gravitationally stable in the Newtonian sense is applied. In other words, subject to the caveat that the analysis applies to a highly idealized model, the Baryonic Tully-Fisher Relationship (BTFR) is shown to arise as a consequence of Newtonian gravitation acting in a hierarchical Universe. We discuss the ramifications of this result, which are significant and non-trivial.