Formation of caustics in k-essence and Horndeski theory

  title={Formation of caustics in k-essence and Horndeski theory},
  author={Eugeny Babichev},
  journal={Journal of High Energy Physics},
  • E. Babichev
  • Published 1 February 2016
  • Physics
  • Journal of High Energy Physics
A bstractWe study propagation of waves and appearance of caustics in k-essence and galileon theories. First we show that previously known solutions for travelling waves in k-essence and galileon models correspond to very specific fine-tuned initial conditions. On the contrary, as we demonstrate by the method of characteristics, generic initial conditions leads to a wave in k-essence which ends up with formation of caustics. Finally, we find that any wave solution in pure k-essence is also a… 
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