Some more Exotic Dark Matter Candidates: GUT Balls, Fermi Balls...
  The nature of dark matter (DM), which is supposed to constitute about one-fourth of the universe, is still a mystery. There is evidence that much of the DM may be made up of as yet undiscovered particles with several experiments all over the world trying to detect these. In this article we introduce some new candidates which are exotic in nature but still are consistent with known physics. We look at DM objects that can be formed by the balance of gravity with the four-fermion force, nuclear tension, etc. We see that their radii are much larger than their corresponding Schwarzschild radius; hence they are distinct from Hawking primordial black holes. We have determined their mass and the required number densities to account for the DM in the galaxy and possible ways of detecting them. 
C. Sivaram (1) and Kenath Arun (2) ((1) Indian Institute of   Astrophysics, Bangalore, (2) Christ Junior College, Bangalore)
physics.gen-ph