From: Andrew Johnson Date: 2017-09-20 19:59:08 Attachments :Thanks to Dan for sending me this one!  A nicely paced and interesting video, focusing mainly on the construction of some of the amazing walls/buildings there (and elsewhere).  However, he’s wrong about the “Starchild skull #2” –  it is almost…

From: Andrew Johnson Date: 2017-09-18 15:58:23 Thanks for Ron for sending me this link:  https://www.nature.com/articles/srep38965    AbstractInvestigations of invisibility cloaks have been led by rigorous theories and such cloak structures, in general, require extreme material parameters. Consequently, it is challenging to realize them, particularly in the full…