It is a pleasure to thank Paul Bradley, Adam Burrows, Harald Dimmelmeier, Alex Heger, Scott Hughes,
Hui Li, Ewald Müller, Ken Nomoto, Shangli Ou, and Stuart Shapiro for helpful conversations and/or
permission to reprint figures/movies from their published works. We also gratefully acknowledge Ewald
Müller and a second referee for their beneficial reviews of this article’s first version. This work was
performed under the auspices of the U.S. Department of Energy by the Los Alamos National Laboratory
under contract W-7405-ENG-36.