Paper-boat relaxion
  A new relaxion mechanism is proposed where a small electroweak scale is
preferably selected earlier than the larger one due to a potential instability,
which is different from previously proposed stopping mechanisms by either
Hubble friction from an increasing periodic barrier or thermal friction from
gauge boson production. The sub-Planckian field excursion of an axion can be
achieved without violating the bound on the $e$-folding number from a quantum
gravity perspective; and our relaxion can be identified as a QCD axion,
preserving the Peccei-Quinn solution to the strong $CP$ problem as well as
making up all the cold dark matter in our current Universe.
