@ARTICLE{Zhang2023-ef,
  title     = "Nonconvex ancient solutions to curve shortening flow",
  author    = "Zhang, Yongzhe and Olson, Connor and Khan, Ilyas and Angenent,
               Sigurd",
  abstract  = "We construct an ancient solution to planar curve shortening. The
               solution is at all times compact and embedded. For
              $ t\ll 0$ it is approximated by the rotating Yin-Yang
               soliton, truncated at a finite angle $\alpha( t ) = − t$,
               and closed off by a small copy of
               the Grim Reaper translating soliton.",
  journal   = "Trans. Am. Math. Soc.",
  publisher = "American Mathematical Society (AMS)",
  month     =  jul,
  year      =  2023,
  language  = "en"
}