(Del Popolo 2014b; Del Popolo & Gambera 2000); b) the discrepancy between the large discs of observed spirals and the small discs obtained in Smooth Particle Hydrodynamics (SPH) simulations, referred to as the angular momentum catastrophe (AMC, van den Bosch, Burkert,& Swaters, 2001); c) the discrepancy between the number of predicted and observed subhaloes when running N-body simulations (Klypin et al. 1999; Moore et al. 1999)[^3], dubbed the “missing satellite problem (MSP).

Klypin et al. (1999), and Moore et al. (1999) noticed, in numerical simulations of galactic and cluster haloes, an excess of predicted subhaloes compared with observation. They had found $\simeq500$ satellites with circular velocities larger than Ursa-Minor and Draco, while the MW dwarf Spheroidals (dSphs) are well known to be far fewer (the Large and Small Magellanic Clouds, and 9 bright dSphs (Boylan-Kolchin, Bullock, and Kaplinghat 2012)). The problem was later confirmed in subsequent cosmological simulations (Aquarius, Via Lactea II (VL2), and GHALO simulations – Springel et al. 2008; Stadel et al. 2009; Diemand et al. 2007). Although insufficiently for a complete solution, it was alleviated with the discovery of the ultra-faint MW satellites (Willman et al. 2005; Belokurov 2006; Zucker 2006; Sakamoto & Hasegawa 2006; Irwin et 