Challenges to global solutions in Horndeski's theory
  We explore the question of obtaining global solutions in Horndeski's theories
of gravity. Towards this end, we study a relevant set of the theory and, by
employing the Einstein frame we simplify the analysis by exploiting known
results on global solutions of wave equations. We identify conditions for
achieving global solutions as well as obstacles that can arise to spoil such
goal. We illustrate such problems via numerical simulations.
