The best of the rest from the Physics arXiv this week:
Mathematicians prove that a three-stranded rope is always 68% the length of its component strands, regardless of the material from which it is made.
A team from NIST measures the smallest force ever recorded, beating the previous best by three orders of magnitude
The idea that the Earth shows signs of having repeatedly passed through the tail of a comet does not bear up to scrutiny.
Researchers report a major boost in energy-harvesting devices.
Legal options remain after court blocks FCC's effort to guarantee fair network access.
One of the sun's closest neighbors is a wandering, Jupiter-sized object just nine light-years away, say astronomers.
There is intense optimism that the country can become the "cradle of clean energy."
The widespread belief that pulsars are the best clocks in the universe is wrong, say physicists.
Apple's "magical and revolutionary" device is quite a good e-reader, though.