arXiv:1211.4792 · Physical Review LettersComment on “Space-Time Crystals of Trapped Ions”P. BrunoPublished Jul 10, 2013• 59 citationsarXivHTMLPDFAbstractA Comment on "Space-Time Crystals of Trapped ions", by Tongcang Li et al. (PRL 109, 163001 (2012); arXiv:1206.4772DOI10.1103/physrevlett.111.029301