Peculiar motions, accelerated expansion and the cosmological axis

  title={Peculiar motions, accelerated expansion and the cosmological axis},
  author={Christos G. Tsagas},
  journal={Physical Review D},
  • C. Tsagas
  • Published 20 July 2011
  • Physics
  • Physical Review D
Peculiar velocities change the expansion rate of any observer moving relative to the smooth Hubble flow. As a result, observers in a galaxy like our Milky Way can experience accelerated expansion within a globally decelerating universe, even when the drift velocities are small. The effect is local, but the affected scales can be large enough to give the false impression that the whole cosmos has recently entered an accelerating phase. Generally, peculiar velocities are also associated with… 

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