For twenty years, the fastest known algorithm to multiply two n-by-n matrices, due to Coppersmith and Winograd, took a leisurely O(n^2.376) steps. Last year, though, buried deep in his PhD thesis, Andy Stothers discussed an improvement to O(n^2.374) steps. And today, Virginia Vassilevska Williams of Berkeley and Stanford, released a breakthrough paper [pdf] that improves the matrix-multiplication time to a lightning-fast O(n^2.373) steps. [via] [more inside]
posted by albrecht
on Nov 29, 2011 -
is the fabled Tyrannosaurus practiced in the skills of trigonometry and long division. Apparently he knows all eight numbers. [Via]
posted by homunculus
on Nov 11, 2011 -
One way to measure corporate fraud
is look at reported numbers and see if they follow Benford's law
- number sets that are manipulated usually deviate from Benford's law. A recent
analysis of all public companies over the past 50 years has shown a steady upward deviation, strongly suggesting there is more corporate fraud now than ever before (peaked in 2008). [more inside]
posted by stbalbach
on Oct 13, 2011 -
Who's Afraid of the Seven Times Table? Ernst Kummer, one of the great mathematicians of the late 1800s, was hopeless at arithmetic. He was giving an advanced maths lecture and in the middle of a complicated calculation he needed to know what six times seven was. “Um ... six times seven is ... six times seven . . .” A student put up his hand: “41, Professor.” Kummer chalked 41 on the blackboard. “No, no, Professor!” shouted another. “It’s 44!” Kummer gave the students a quizzical look. “Come, come, gentlemen. It can’t be both. It must be either one or the other!” [more inside]
posted by storybored
on Sep 27, 2011 -
"Perhaps twenty or thirty people in England may be expected to read this book."
G.H. Hardy's review of Whitehead and Russell's Principia Mathematica
, published in the Times Literary Supplement 100 years ago last week. "The time has passed when a philosopher can afford to be ignorant of mathematics, and a little perseverance will be well rewarded. It will be something to learn how many of the spectres that have haunted philosophers modern mathematics has finally laid to rest."
posted by escabeche
on Sep 12, 2011 -
Donald in Mathmagic Land
is a 27-minute Donald Duck featurette released on June 26, 1959. As Walt Disney said, "We have recently explained mathematics in a film and in that way excited public interest in this very important subject." (Wiki)
posted by twoleftfeet
on Aug 9, 2011 -
Old Theories As Limits of New Ones
-- Theoretical physicist, Lubos Motl, takes a brief tour through the history of physics, and explains the simple mathematical relationship of old theories to the theories that replace them.
posted by empath
on Aug 5, 2011 -
Bret Victor on WorryDream
The power to understand and predict the quantities of the world should not be restricted to those with a freakish knack for manipulating abstract symbols.
When most people speak of Math, what they have in mind is more its mechanism than its essence. This "Math" consists of assigning meaning to a set of symbols, blindly shuffling around these symbols according to arcane rules, and then interpreting a meaning from the shuffled result. The process is not unlike casting lots.
posted by naight
on Jul 24, 2011 -
is a veteran American cartoonist best known for his delightful comic-book guides to science and history, many of which have previews online. Chief among them is his long-running Cartoon History of the Universe
(later The Cartoon History of the Modern World
), a sprawling multi-volume opus documenting everything from the Big Bang to the Bush administration. Published over the course of three decades, it takes a truly global view -- its time-traveling Professor thoroughly explores not only familiar topics like Rome and World War II but the oft-neglected stories of Asia and Africa, blending caricature and myth with careful scholarship (cited by fun illustrated bibliographies
) and tackling even the most obscure events with intelligence and wit
. This savvy satire carried over to Gonick's Zinn
chronicle The Cartoon History of the United States
, along with a bevy of Cartoon Guides
to other topics, including Genetics, Computer Science, Chemistry, Physics, Statistics, The Environment
, and (yes!) Sex
. Gonick has also maintained a few sideprojects, such as a webcomic look at Chinese invention
, assorted math comics
), the Muse magazine
mainstay Kokopelli & Co.
(featuring the shenanigans of his "New Muses"
), and more
. See also these lengthy interview snippets
, linked previously
. Want more? Amazon links to the complete oeuvre inside! [more inside]
posted by Rhaomi
on Jun 6, 2011 -
"As recently as a year ago, there were many publishers, librarians, and scholars who thought that electronic publishing was just a passing fad."
In 1996, the number theorist Andrew Odlyzko
, a pioneer in the development of "experimental mathematics" via large-scale computation, wrote a article, prescient in many respects, about the effect the Internet would have on the economics of scholarly publication, and on commerce more generally.
posted by escabeche
on May 29, 2011 -
Do you like integer sequences? Do you like poking around in the The On-Line Encyclopedia of Integer Sequences
? Do you think, whoa, wait, okay, actually I like integer sequences but the OEIS is a goddam intractable maze of numbers? Do you think, man, what I wish is that someone would make an accessible blog that discusses some of the interesting entries in the OEIS for the casual fan of integer sequences? Well, that's an amazing coincidence; you should take a look at The On-Line Blog of Integer Sequences
, by our very own Plutor
posted by cortex
on May 5, 2011 -
This is what pi sounds like.
At least, that's one person's interpretation. There are certainly plenty of others
, including touchtone pi
, hammered dulcimer pi
, violin pi
, smooth techno pi
, crazy awesome pi
, vaguely unsettling pi
(sounds best with headphones), and lots of piano pi
. Pi has even done a duet with its buddy e
. Nothing here that tickles your fancy? Think you could do better? Why not make your own pi song
? Hell, make two
! If you're having trouble remembering all those pesky digits, don't worry: there's a song for that, too
.(pi as music previously on metafilter)
posted by Captain Cardanthian!
on Mar 8, 2011 -
Rediscovering WWII's female "computers"
. While researching a documentary in Philadelphia, filmmaker LeAnn Erickson came across two women with a story she'd never heard before: thousands of women with advanced mathematical skills employed as "computers", working day and night during WWII to supply soldiers in the field with precise ballistics algorithms. Some of those women also went on to program ENIAC
, the first general-purpose computer (previously
). Erickson turned their stories into Top Secret Rosies
, a documentary released to theaters last year and to DVD this month. One of those programmers, Betty Jean Jennings Bartik, spoke at length
to the Computing History Museum in 2008. [youtube, 1:07:19] [via
posted by Errant
on Feb 8, 2011 -
Horizon asks "What is reality?"
-- youtube for links for those outside the UK: 1
. It's a hard question. To help you answer it, Stanford has a set of free courses available on line by Leonard Susskind:
, New Revolutions in Particle Physics
, Quantum Entanglement
, Special Relativity
, Classical Mechanics
, Statistical Mechanics
, The Standard Model
. (Each link is to lecture 1 of a full college course of a dozen or so lectures.) If you need help with the math, the Khan Academy
should help get you up to speed.
posted by empath
on Jan 23, 2011 -
Google is known to ask the following question in job interviews: In a country in which people only want boys every family continues to have children until they have a boy. If they have a girl, they have another child. If they have a boy, they stop. What is the proportion of boys to girls in the country?
Think you know the answer? If so, Steve Landsburg may be willing to bet you up to $5000. [more inside]
posted by gsteff
on Jan 1, 2011 -
"Normal" human pregnancies last 40 weeks, right? Well, no; they can vary quite a bit by the mother's race
, number of previous children
, family history of delivering early or late
, home state
, work habits
, and even the fetus' HLA type
. So where does that "40 week" thing come from? Oh, dear.
So check out this super-nerdy pregnancy statistics
website, from an engineer mom who is collecting data from the public
(see the raw data
and auto-generated graphs
, and read the FAQ about the survey, with more cool graphs
). Looking for day-by-day
probabilities on when that baby's due? This would be your stats table with daily prediction
(adjust dates at top of page as needed). Of course, you could always shut up your constantly inquiring relatives and friends another way
posted by Asparagirl
on Dec 16, 2010 -
Measure-theoretic probability: Why it should be learnt and how to get started.
The clickable chart of distribution relationships.
Just two of the interesting and informative probability resources I've learned about, along with countless other tidbits of information, from statistician John D. Cook
and his probability fact-of-the-day Twitter feed ProbFact
. John also has daily tip and fact Twitter feeds for Windows keyboard shortcuts
, regular expressions
, TeX and LaTeX
, algebra and number theory
, topology and geometry
, real and complex analysis
, and beginning tomorrow, computer science
posted by grouse
on Dec 5, 2010 -
Let's say you're me and you're in math class, and you're supposed to be learning about factoring. Trouble is, your teacher is too busy trying to convince you that factoring is a useful skill for the average person to know with real-world applications ranging from passing your state exams all the way to getting a higher SAT score and unfortunately does not have the time to show you why factoring is actually interesting. It's perfectly reasonable for you to get bored in this situation. So like any reasonable person, you start doodling. [more inside]
posted by ErWenn
on Dec 3, 2010 -