Twinlike models for parametrized dark energy
  We study cosmological models involving a single real scalar field that has an
equation of state parameter which evolves with cosmic time. We highlight some
common parametrizations for the equation of state as a function of redshift in
the context of twinlike theories. The procedure is used to introduce different
models that have the same acceleration parameter, with the very same energy
densities and pressure in flat spacetime.
