Phil Keenan, at Meandering through Mathematics, explores how the logarithm is calculated numerically. Interestingly, calculating it as the inverse of the exponential seems to be more efficient than using the Taylor series.
Hopefully this one doesn’t remind anybody of a traumatic experience they had five days ago: XKCD on the Valentine dilemma. On a related note, you might be interested in William Spaniel’s Game Theory 101 videos or the free online Stanford game theory course by Matthew Jackson and Yoav Shoham (economics and CS, respectively) that’s starting soon.
Cathy O’Neil compares the recent Elsevier journal boycott to the Occupy movement.
The collapse of the Soviet Union and the productivity of American mathematicians, an NBER working paper by George J. Borjas and Kirk B. Doran. The basic claim is that when Soviet mathematicians were able to emigrate to the US in the 1990s, this pushed aside mathematicians already in the US rather than “growing the mathematical pie”.
Niles Johnson has a video on visualizing seven-manifolds.
Cary and Michael Huang have an interactive thing-to-play-with on the scale of the universe. This is even more impressive when I find out they’re half my age.
Birth timing and Valentine’s Day. (Also Halloween.)
At MathOverflow: how to motivate and present ε-δ proofs to undergraduates.
From the New York Times magazine: How companies learn your secrets.
John Nash’s letter to the NSA (via Turing’s Invisible Hand and hacker news)
John Baez has a series of posts on the roots of polynomials having integer coefficients, titled “The Beauty of Roots”: part one, part two, part three, easy version of slides from a talk, similar slides with some proofs. (Joint work between Baez, Dan Christensen, and Sam Derbyshire.)