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398 posts tagged with Mathematics.

Displaying 201 through 250 of 398. Subscribe:

## "Enhance 15 to 23. Give me a hard copy right there."

## Economics and Physics Envy

"Take a little bad psychology, add a dash of bad philosophy and ethics, and liberal quantities of bad logic, and any economist can prove that the demand curve for a commodity is negatively inclined." MIT economist Andrew Lo and string theorist turned asset manager Mark Mueller on the "physics envy" that plagues economics, and how to stop worrying and love uncertainty.

## Amazonian tribe and maths

Does a group of indigenous South Americans hold the key to our relationship with maths?

*Still, I thought it odd that numbers larger than five did not crop up at all in Amazonian daily life. What if you ask a Munduruku with six children how many kids they have? "He will say, 'I don't know,'" Pica said. "It is impossible to express."*## You are disturbing me. I am picking mushrooms.

Grigori Perelman has refused one million dollars from the Clay Mathematics Institute for his solution to the Poincaré conjecture. Despite some pressure to take the money and give it to one party or another, Perelman insists "I am not a hero of mathematics. I am not successful at all, and I do not want to be observed by everyone." Perelman previously refused the Fields Medal, mathematics' highest honor. (Previously.)

## Nature by Numbers

Nature by Numbers is a new animated short film by Cristóbal Vila (previously) inspired by some mathematical constructs found in nature. (via)

## Very large numbers

The Shannon number? Skewes' number? Graham's number? Please. When you're ready to get serious, here are some truly large numbers. (previously, but with dead links)

## Found Functions

Found Functions. An elegant demonstration of beauty in mathematics (and landscape). Nikki Graziano is a math and photography student at Rochester Institute of Technology; some of her photographs were recently featured in Wired. Graziano "overlays graphs and their corresponding equations onto her carefully composed photos. ... Graziano doesn’t go out looking for a specific function but lets one find her instead. Once she’s got an image she likes, Graziano whips up the numbers and tweaks the function until the graph it describes aligns perfectly with the photograph."

## "The coroner’s report from Argentina makes slighting mention of a brain tumor..."

"Back in 1993 I was tutoring my sister in algebra. Her quizzes and tests were always made of word problems with a running storyline involving many recurring places and characters. I tied the fate of the main characters to how well she did on the previous quiz, so a good performance brought them good fortune. Unfortunately, one test she completely bombed, and, well, this is a transcription of the quiz she got next." [more inside]

## The Unreasonable Effectiveness of Mathematics in the Natural Sciences

The Unreasonable Effectiveness of Mathematics in the Natural Sciences is a 1960 essay by Eugene Wigner. Via Steve Strogatz.

## Math class is hard.

*Early elementary school teachers in the United States are almost exclusively female (>90%), and we provide evidence that these female teachers’ anxieties relate to girls’ math achievement via girls’ beliefs about who is good at math.*A study (abstract and full-text [pdf]) by the University of Chicago Department of Psychology and Committee on Education found a link between math anxiety in elementary school teachers and their female students' math abilities. [more inside]

## Calculus Lifesaver

The Calculus Lifesaver lectures -- videos available here in streaming (Real Player), mp4 and wmv formats -- were originally given as "review sessions for the Princeton introductory calculus courses MAT103 and MAT104 during the 2006/7 academic year". Each lecture is about 2 hours.

## The beauty of roots

The beauty of roots. From Dan Christensen and Sam Derbyshire via John Baez. If you like algebra: these are plots of the density in the complex plane of roots of polynomials with small integral coefficients. If you don't: these are extravagantly beautiful images produced from the simplest of mathematical procedures. Explore the image interactively here.

## maths in alice

Alice's adventures in algebra: Wonderland solved "Outgunned in the specialist press, Dodgson took his mathematics to his fiction. Using a technique familiar from Euclid's proofs, reductio ad absurdum, he picked apart the "semi-logic" of the new abstract mathematics, mocking its weakness by taking these premises to their logical conclusions, with mad results. The outcome is Alice's Adventures in Wonderland."

## Math Overflow

Math Overflow is the first attempt to use the Stack Exchange platform, already popular with programmers, as a scientific research tool. Founded this month by a group of young mathematicians, including Scott Morrison and Ben Webster of the Secret Blogging Seminar, the site is already wrestling with hundreds of questions, ranging from the technical ("When is a map given by a word surjective?") to the historical ("Most interesting mathematics mistake?")

## cosmic spiral visuals

The Anatomy of Spiral Arms,

*shows how galaxies naturally evolve to form grand-design two-arm spirals.*The Hubble Ultra Deep Field in 3D. [more inside]## Figure 3. Basic model outbreak scenario. Susceptibles are quickly eradicated and zombies take over, infecting everyone.

## 3D Mapping

Durango Bill's Home Page. With topics that include: 3D end-to-end tour of the Grand Canyon, the origin and formation of the Colorado River, and examples of river systems that cut through mountain ranges instead of taking easier routes around them in Ancestral Rivers of the World. [more inside]

## Surely not joking, Mr. Feynman

"

*I can see the audience tonight, so I can see also from the size of it that there must many of you here who are not thoroughly familiar with physics, and also a number that are not too versed in mathematics- and I don't doubt that there are some who know neither physics nor mathematics very well. That puts a considerable challenge on a speaker who is going to speak on the relation of physics and mathematics- a challenge which I, however, will not accept: I published the title of the talk in clear and precise language, and didn't make it sound like it was something it wasn't- it's the relation of physics and mathematics - and if you find that in some spots it assumes some minor knowledge of physics or mathematics, I cannot help it. It was named."*The Feynman Messenger series at Cornell has been made available online for the first time thanks to Bill Gates.## Algorithmic Music

The principles of Harmonics were discovered by Pythagoras c.587-c.507 B.C. during travels to Egypt and throughout the ancient world. Hans Kayser made a profound philosophic study of harmonics in the 20th century. Algorithmic composition is the technique of using harmonic algorithms to create music. Drew Lesso has been creating algorithmic music since 1975. Samples like

*Crystal, Constellations, or Planet Earth*demonstrate the math behind the music. Over the years, Lesso has collaborated with many other musicians and poets to create an airy, evolutionary legacy.## Gimme That Old Time Derivation

The Cornell Historical Math Monographs archive has a great many famous papers, including works by De Morgan, Hamilton, Descartes (warning: French) and of course Lewis Carroll. [more inside]

## He laughed like an irresponsible foetus

**Parts 1, 2, 3 of a 1959 interview**with philosopher, mathematician and peace campaigner Bertrand Russell (1872-1970). Works and pictures online include Anti-suffragist Anxieties, Why I am not a Christian, the Russell-Einstein Manifesto against nuclear weapons and the book The Conquest of Happiness. Russell is also known for his pithy quotes, his teapot and was the subject of poem Mr Apollinax by T.S. Eliot.

## Computable data* (conceivably knowable) about people

Stephen Wolfram discusses Wolfram|Alpha: Computational Knowledge Engine - at the same time Google Adds Search to Public Data, viz: "Nobody really paid attention to the two hour snorecast" -- like a cross between designing for big data and a glossary of game theory terms -- on Wolfram|Alpha (previously), yet the veil is being lifted nonetheless: "[on] a platonic search engine, unearthing eternal truths that may never have been written down before," cf. hunch & cyc (and in other startup news...) [via] [more inside]

## I See Your "The Watchmen," and I Raise You "Logicomix"

Logicomix: An Epic Search for Truth by Apostolos Doxiadis, Christos H. Papadimitriou, Alecos Papadatos, and Annie Di Donna.
Covering a span of sixty years, the graphic novel Logicomix was inspired by the epic story of the quest for the Foundations of Mathematics. This is another kind of epic battle that does not quite lead where the characters thought it would take them. Featuring Bertrand Russell as narrator and the awesome might of the villain (of sorts) Incompleteness. Themes include the high personal price paid for knowledge.

## Information doesn't want to be scale free

"the scale-free network modeing paradigm is largely inconsistent with the engineered nature of the Internet..." For a decade it's been conventional wisdom that the Internet has a scale-free topology, in which the number of links emanating from a site obeys a power law. In other words, the Internet has a long tail; compared with a completely random network, its structure is dominated by a few very highly connected nodes, while the rest of the web consists of a gigantic list of sites attached to hardly anything. Among its other effects, this makes the web highly vulnerable to epidemics. The power law on the internet has inspired a vast array of research by computer scientists, mathematicians, and engineers.
According to an article in this month's Notices of the American Math Society, it's all wrong. How could so many scientists make this kind of mistake? Statistician Cosma Shalizi explains how people see power laws when they aren't there: "Abusing linear regression makes the baby Gauss cry."

## The H&FJ Institute for Unapplied Mathematics

Joe Palca, a science correspondent for NPR's Morning Edition, was meditating on the best way to convey the magnitude of the world's largest known prime number, 2

^{43112609}-1. He contacted H&FJ at Typography.com to discuss the implications of typesetting a number with more than twelve million digits. Crunching of numbers and fonts ensued.## Fun for all ages, dimensions.

Topology and Geometry Software by Jeff Weeks.

## Does Your Answer Seem Right?

NYT Guesstimation Quiz. Enrico Fermi estimated the yield of the Trinity A-bomb test by dropping some shredded paper. He also asked his students to estimate unusual quantities like the number of piano tuners in Chicago - to show that just about anything can be estimated without detailed knowledge.

## dY dVorce = ?

Oxford Professor & Fellow of the Royal Society James Murray uses mathematical modelling to predict whether a marriage will survive or end in divorce, with 94% accuracy.
His lecture to the Royal Society will be available for view on demand within two days.

## The On-Line Encyclopedia of Integer Sequences

Ever wondered what comes next, and why? The On-Line Encyclopedia of Integer Sequences has the answers. (Previously.)

## MacTutor History of Mathematics archive

The MacTutor History of Mathematics archive is an astounding collection of historical material on mathematics, especially biographies. (Previously: 1 2 3 4.)

## A vote for "The Indefatigable Frog" is a vote for posterity.

"Do you like fiction and mathematics? Are you interested in what our society thinks about mathematicians?" [more inside]

## Homework Helper

World of Science contains budding encyclopedias of astronomy, scientific biography, chemistry, and physics. This resource has been assembled over more than a decade by internet encyclopedist Eric Weisstein with assistance from the internet community. MeFi visited Weisstein's Mathworld a couple years ago.

## Real mathematics is (or at least should be) algorithmic. The axiomatic method is like machine language or a Turing machine or a Tuxedo. It is very stifling.

One night, very late, I was browsing the internet, using my current computer, Shalosh B. Ekhad, III. I was searching for "Ekhad". All of a sudden, to my amazement, I chanced on a website whose last update was Sept. 30, 2050, and found this little Elementary Geometry textbook.
This text may seem a bit strange to 2001 humans. It appears that there are no proofs, only statements, in Maple, using English-based names for the definitions and theorems. But THE STATEMENT IS THE PROOF, ready to be run on Maple, that will output "true" if the proof-statement is correct, and "false" otherwise. [more inside]

## All Things Mathematical

Somewhere between 538 and xkcd, Ask Doctor Math is an advice column for practical math questions. [more inside]

## The Spherical Wave Structure of Matter in Space

On Truth and Reality. Despite several thousand years of failure to correctly understand physical reality (hence the current postmodern view that this is impossible) it is actually very simple to work out how matter exists and moves about in Space. The rules of Science (Occam's Razor / Simplicity) and Metaphysics (Dynamic Unity of Reality) require that reality be described from only one single source existing, as Leibniz wrote:

*"because of the interconnection of all things with one another."*[more inside]## Exponential, what it do?

Division: Work it out! - these girls be spittin the math.

## You and Your Research

You and Your Research was a talk given by Richard Hamming in 1986. Read it if you have an interest in doing first-class work.

## art and science folded together

MetaFilter's Eric Gjerde has just come out with a book, Origami Tessellations: Awe-Inspiring Geometric Designs. Eric also makes really unusual, complex and mathematically interesting origami. His site has all kinds of cool things to look at and explore, like Owen Jones' The Grammar of Ornament, Joel Cooper's amazing paper sculptures and Ernst Haeckel's awesome book, Kunst-Formen der Natur. [more inside]

## Droste Effect Video

You might have seen the Droste Effect before, perhaps even the animated version. But here's a new iteration - a music video.

## you really should watch this.

Hunting the Hidden Dimension. You may be familiar with fractals, but in this PBS Nova episode, divided online into 5 parts, fractals go beyond the impossible zoom of the Mandelbrot set. Scientists are using fractals to describe complex natural occurrences, like lava, capillaries, and rain forests. In part 5, scientists measure one tree in the rain forests, and the distribution of small and large branches mirror the distribution of small and large trees. Fractals, it seems, are nature.

## Data-Driven Enhancement of Facial Attractiveness

## Math Education: An Inconvenient Truth

Math Education: An Inconvenient Truth. How children learn (or: don't learn) math today. [more inside]

## Seeing in four dimensions

Mathematicians create videos that help in visualizing four-dimensional objects. Science News writes about it: seeing in four dimensions.

## Who is Alexander Grothendieck?

Who is Alexander Grothendieck? [PDF]

*This lecture is concerned not with Grothendieck's mathematics but with his very unusual life on the fringes of human society. In particular, there is, on the one hand, the question of why at the age of forty-two Grothendieck first of all resigned his professorship at the Institut des Hautes Etudes Scientifiques (IHES); then withdrew from mathematics completely; and finally broke off all connections to his colleagues, students, acquaintances, friends, as well as his own family, to live as a hermit in an unknown place. On the other hand, one would like to know what has occupied this restless and creative spirit since his withdrawal from mathematics.*## It's more free maths!

Online Encyclopedia of Mathematics Edited by Michiel Hazewinkel (CWI, Amsterdam), and originaly published in dead tree form in 2002, now free to browse and poke into. [more inside]

## Bite me, Larry Summers.

No gender differences found in math performance. None. Not on average, at least in countries where the sexes are treated equally. And no, not at the highest, outlier levels of mathematical ability, either, despite what some believe.
And not in number of undergrad math degrees earned. And not in terms of complex problem solving ability. Just plain not.

## Rock the streets

Whether you want to learn to lace shoes, tie shoelaces, stop shoelaces from coming undone, calculate shoelace lengths or even repair aglets, Ian's Shoelace Site has the answer!

## A "Harmonious" Path

Accidental Astrophysicists: "They started with algebra and ended up learning about gravitational lensing (PDF)." [Via linkfilter]

## A Woolen Reef

## Reality

The Reality Tests. "A team of physicists in Vienna has devised experiments that may answer one of the enduring riddles of science: Do we create the world just by looking at it?"