Note that different people have different research approaches. The two old ladies check that none of them can see herself and the problem is solved! ;-)
The other older lady makes an experiment with motion and rigorously determines that she is ... well ... unsichtbar. :-)
Other Interesting arXiv Papers (Week Ending 18 May 2013) - The best of the rest from the Physics arXiv preprint server Performance of a Remotely Located Muon Radiography System to Identify the Inner Structure of ...
1 day ago