Two Solutions of the `Galaxy Rotational Velocity Problem' Applied to the Milky Way

We argue that the usual galactic equations are incorrect or have been incorrectly applied. Instead it is the spatially-averaged Euler equations and Gauss' gravitational law which apply. Our first solution integrates these equations across the galaxy disc to obtain a radial momentum integral equation. Application to the Milky Way using velocity measurements and the observed baryonic matter distribution shows that the momentum thickness varies nearly linearly with increasing radius.. It is NOT accounting for this `fanning out' that leads to the so-called `Galaxy Rotational Velocity Problem', and the subsequent need to infer Dark Matter. A second equilibrium similarity solution confirms the linear `fanning out' of the galactic disk, and also shows that away from the core, the `mean' streamlines form a logarithmic spiral, The log spiral with constant 6.5 is an excellent fit to both the published velocity data and published artistic constructions of the Milky Way. All theoretical prediction are in excellent agreement with the data without needing new physics or modifying existing gravitational laws..