A Yang-Mills Type Gauge Theory of Gravity and the Dark Matter and Dark   Energy Problems
  A Yang-Mills type gauge theory of gravity is shown to have a richer structure than the Einstein's General Theory of Relativity. This new structure can give an explanation of the form of the galactic rotation curves, of the amount of intergalactic gravitational lensing, and of the accelerating expansion of the Universe. 
Yi Yang, Wai Bong Yeung
physics.gen-ph gr-qc