Notes about math

July 16, 2012 permalink

Random Numbers Through a Quantum Vacuum

Your random number generator not truly random enough for you? Maybe you should try some of the numbers coming off of the Australian National University’s quantum vacuum randomization server. Nothing like minute variations in a field of near-silence to get some unfettered randomness, I guess. They offer access to the vacuum through a few different forms of data – seen above is a chunk of their randomly-colored pixel stream. Science!

(Via Science Daily)

August 13, 2011 permalink

Nomographs

From a post titled The Art of Nomography on Dead Reckonings (a blog dedicated to forgotten-but-beautiful mathematical systems! I’d better subscribe to this one…) :

Nomography, truly a forgotten art, is the graphical representation of mathematical relationships or laws (the Greek word for law is nomos). These graphs are variously called nomograms (the term used here), nomographs, alignment charts, and abacs. This area of practical and theoretical mathematics was invented in 1880 by Philbert Maurice d’Ocagne (1862-1938) and used extensively for many years to provide engineers with fast graphical calculations of complicated formulas to a practical precision.

Along with the mathematics involved, a great deal of ingenuity went into the design of these nomograms to increase their utility as well as their precision. Many books were written on nomography and then driven out of print with the spread of computers and calculators, and it can be difficult to find these books today even in libraries. Every once in a while a nomogram appears in a modern setting, and it seems odd and strangely old-fashioned—the multi-faceted Smith Chart for transmission line calculations is still sometimes observed in the wild. The theory of nomograms “draws on every aspect of analytic, descriptive, and projective geometries, the several fields of algebra, and other mathematical fields” [Douglass].

More about nomograms and abacs on Wikipedia.

(Via O’Reilly Radar)

November 27, 2009 permalink

But Gladwell Frequently Holds Forth About

But Gladwell frequently holds forth about statistics and psychology, and his lack of technical grounding in these subjects can be jarring. He provides misleading definitions of “homology,” “saggital plane” and “power law” and quotes an expert speaking about an “igon value” (that’s eigenvalue, a basic concept in linear algebra). In the spirit of Gladwell, who likes to give portentous names to his aperçus, I will call this the Igon Value Problem: when a writer’s education on a topic consists in interviewing an expert, he is apt to offer generalizations that are banal, obtuse or flat wrong.

October 11, 2009 permalink

Phillip Torrone Rides the Square Wheeled Tricycle

(video no longer available)

Phillip Torrone rides the square-wheeled tricycle from the Math Midway, a traveling exhibition of mathematics. Figuring out what kind of catenary curves would be needed for differently shaped wheels is a branch of mathematics that I’m happy  exists (as far as I know the problem dates back on some level to the 1960s, but for a good recent illustration of the math involved, check out this PDF from a St. Norbert College mathematical modeling class).

(Via Make)

Pagination