MetaFilter posts tagged with Mathematics
http://www.metafilter.com/tags/Mathematics
Posts tagged with 'Mathematics' at MetaFilter.Sun, 11 Sep 2016 05:29:11 -0800Sun, 11 Sep 2016 05:29:11 -0800en-ushttp://blogs.law.harvard.edu/tech/rss60Not just Phobos and Deimos
http://www.metafilter.com/162203/Not%2Djust%2DPhobos%2Dand%2DDeimos
<a href="http://hopsblog-hop.blogspot.com/2016/09/general-template-for-space-elevators.html">Space elevators, ZRVTOs and conic sections</a> (and <a href="http://hopsblog-hop.blogspot.com/">quite a bit more on the rest of the blog</a>) tag:metafilter.com,2016:site.162203Sun, 11 Sep 2016 05:29:11 -0800WolfdogAnimated math
http://www.metafilter.com/162201/Animated%2Dmath
<a href="https://www.youtube.com/playlist?list=PLZHQObOWTQDPD3MizzM2xVFitgF8hE_ab">Essence of linear algebra</a> - "[<a href="https://twitter.com/3blue1brown">Grant Sanderson</a> of <a href="http://www.3blue1brown.com">3Blue1Brown</a> (<a href="https://www.khanacademy.org/math/linear-algebra/eola-topic">now at Khan Academy</a>) <a href="https://twitter.com/3Blue1Brown/status/772904942365347840">animates</a>] the geometric intuitions underlying linear algebra, making the many matrix and vector operations feel less arbitrary." <ol><li><a href="https://www.youtube.com/watch?v=fNk_zzaMoSs">Vectors, what even are they?</a> - "I imagine many viewers are already familiar with vectors in some context, so this video is intended both as a quick review of vector terminology, as well as a chance to make sure we're all on the same page about how specifically to think about vectors in the context of linear algebra." (9:48)</li>
<li><a href="https://www.youtube.com/watch?v=k7RM-ot2NWY">Linear combinations, span, and basis vectors</a> - "The fundamental vector concepts of span, linear combinations, linear dependence and bases all center on one surprisingly important operation: Scaling several vectors and adding them together." (9:55)</li>
<li><a href="https://www.youtube.com/watch?v=kYB8IZa5AuE">Linear transformations and matrices</a> - "Matrices can be thought of as transforming space, and understanding how this work is crucial for understanding many other ideas that follow in linear algebra." (10:54)</li>
<li><a href="https://www.youtube.com/watch?v=XkY2DOUCWMU">Matrix multiplication as composition</a> - "Multiplying two matrices represents applying one transformation after another. Many facts about matrix multiplication become much clearer once you digest this fact." (9:59)
<br> fn. <a href="https://www.youtube.com/watch?v=rHLEWRxRGiM">Three-dimensional linear transformations</a> - "What do 3d linear transformations look like? Having talked about the relationship between matrices and transformations in the last two videos, this one extends those same concepts to three dimensions." (4:42)</li>
<li><a href="https://www.youtube.com/watch?v=Ip3X9LOh2dk">The determinant</a> - "The determinant of a linear transformation measures how much areas/volumes change during the transformation." (9:59)</li>
<li><a href="https://www.youtube.com/watch?v=uQhTuRlWMxw">Inverse matrices, column space and null space</a> - "How to think about linear systems of equations geometrically. The focus here is on gaining an intuition for the concepts of inverse matrices, column space, rank and null space, but the computation of those constructs is not discussed." (12:04)
<br> fn. <a href="https://www.youtube.com/watch?v=v8VSDg_WQlA">Nonsquare matrices as transformations between dimensions</a> - "Because people asked, this is a video briefly showing the geometric interpretation of non-square matrices as linear transformations that go between dimensions." (4:22)</li>
<li><a href="https://www.youtube.com/watch?v=LyGKycYT2v0">Dot products and duality</a> - "Dot products are a nice geometric tool for understanding projection. But now that we know about linear transformations, we can get a deeper feel for what's going on with the dot product, and the connection between its numerical computation and its geometric interpretation." (14:07)</li>
<li><a href="https://www.youtube.com/watch?v=BaM7OCEm3G0">Cross products</a> - "Dot products are a nice geometric tool for understanding projection. But now that we know about linear transformations, we can get a deeper feel for what's going on with the dot product, and the connection between its numerical computation and its geometric interpretation." (8:54)
<br> part 2. <a href="https://www.youtube.com/watch?v=eu6i7WJeinw">Cross products in the light of linear transformations</a> - "This covers the main geometric intuition behind the 2d and 3d cross products." (13:11)</li></ol>
also btw...
<a href="http://setosa.io/ev/eigenvectors-and-eigenvalues/">Eigenvectors and Eigenvalues explained visually</a> - "Eigenvalues/vectors are instrumental to understanding electrical circuits, mechanical systems, ecology and even Google's <a href="http://www.rose-hulman.edu/~bryan/googleFinalVersionFixed.pdf">Page</a><a href="http://www.metafilter.com/140141/Eigendemocracy-crowd-sourced-deliberative-democracy">Rank</a> algorithm. Let's see if visualization can make these ideas more intuitive." (<a href="http://www.epicenecyb.org/archives/date/2016/09#post-22704">via</a>) tag:metafilter.com,2016:site.162201Sun, 11 Sep 2016 00:21:14 -0800kliulessxEuclidx
http://www.metafilter.com/162142/xEuclidx
Compass-and-straightedge construction (aka Euclidean construction) is a method of drawing precise geometric figures using only a compass and a straightedge (like a ruler without the markings). <a href="http://www.mathopenref.com/tocs/constructionstoc.html">MathOpenRef maintains a catalog of many common constructions</a>, each with an explanatory animation and a proof. <a href="https://www.youtube.com/watch?v=LBgIWQcC6lM">This YouTube video</a> demonstrates how to construct almost every <a href="https://en.wikipedia.org/wiki/Constructible_polygon">polygon that can be constructed using these methods</a>. Useful in many decorative arts for laying out figures and patterns, the methods can also be fun to watch, often resulting in an "aha!" moment when one sees how a particular construction is done.
Although not animated, <a href="http://faculty.scf.edu/condorj/256/presentations/Gothic%20Constructions.pdf">this paper</a> [pdf] shows how geometric constructions can be used to create many common Gothic design elements, such as trefoils and arches. tag:metafilter.com,2016:site.162142Thu, 08 Sep 2016 10:29:57 -0800jedicusYou are worth having coffee with.
http://www.metafilter.com/161670/You%2Dare%2Dworth%2Dhaving%2Dcoffee%2Dwith
<a href="https://www.math.hmc.edu/~su/">Francis Su</a> is a professor of mathematics at Harvey Mudd College and the first non-white president of the Mathematical Association of America. In 2013, he presented his Haimo Teaching Award lecture, <a href="http://mathyawp.blogspot.com/2013/01/the-lesson-of-grace-in-teaching.html">The Lesson of Grace in Teaching</a>. For Su, when we learn the lesson of grace—that we have dignity irrespective of accomplishments—and when we impart that lesson to our students, we make good teaching, enthusiastic learning, and honest evaluation possible. <a href="https://www.youtube.com/watch?v=BwJXPRj_CUM">A similar, adapted talk at Wheaton College</a>
Other essays by Francis Su:
<a href="http://www.latimes.com/opinion/op-ed/la-oe-su-women-in-mathematics-20140826-story.html">Solve this math problem: The gender gap </a>
<blockquote>Earlier this month, Maryam Mirzakhani became the first woman in history to win a Fields Medal — "math's Nobel Prize." This is a cause for celebration, but also for reflection. Things are definitely better than they once were for women in mathematics... But Mirzakhani's achievement aside, we are still a long way from adequately recognizing the outstanding work of women.</blockquote>
<a href="https://mathyawp.wordpress.com/2016/08/11/freedom-through-inquiry/">Freedom through Inquiry</a>
<blockquote>Freedom is the ability, in relationship with my peers, to proclaim: "my feet and my head are sticking out of my bed". Or the freedom to say "my proof is wrong" without shame or judgment. Indeed a wrong proof was always a point of delight, because it meant we were seeing something subtle, and it was a challenge to further problem-solving!
What if we could help people across the educational spectrum see a culture of inquiry as a means of producing an environment of freedom: where students can respond to every setback without shame and as a springboard to further investigation?</blockquote> tag:metafilter.com,2016:site.161670Tue, 16 Aug 2016 18:36:33 -0800J.K. SeazerMonumental Proof to Torment Mathematicians for Years to Come
http://www.metafilter.com/161450/Monumental%2DProof%2Dto%2DTorment%2DMathematicians%2Dfor%2DYears%2Dto%2DCome
Nearly four years after Shinichi Mochizuki (<a href="http://www.metafilter.com/153893/The-likelihood-that-theres-interesting-or-important-math-is-pretty-high">previously</a>, <a href="http://www.metafilter.com/127954/Proof-and-Community-Standards">previously</a>, <a href="http://www.metafilter.com/119847/Mathematics-world-abuzz-with-a-proof-of-the-ABC-Conjecture">previously</a>) unveiled an imposing set of papers (<a href="http://www.kurims.kyoto-u.ac.jp/~motizuki/Inter-universal%20Teichmuller%20Theory%20I.pdf">1</a>, <a href="http://www.kurims.kyoto-u.ac.jp/~motizuki/Inter-universal%20Teichmuller%20Theory%20II.pdf">2</a>, <a href="http://www.kurims.kyoto-u.ac.jp/~motizuki/Inter-universal%20Teichmuller%20Theory%20III.pdf">3</a>, <a href="http://www.kurims.kyoto-u.ac.jp/~motizuki/Inter-universal%20Teichmuller%20Theory%20IV.pdf">4</a>) that could revolutionize the theory of numbers, other mathematicians have yet to understand his work or agree on its validity — <a href="http://www.nature.com/news/monumental-proof-to-torment-mathematicians-for-years-to-come-1.20342">although they have made modest progress</a>.</a> Some <a href="http://www.math.columbia.edu/~woit/wordpress/?p=8663">four dozen mathematicians converged last week</a> for a rare opportunity to hear Mochizuki present his own work at a conference on his home turf, Kyoto University's Research Institute for Mathematical Sciences (RIMS).
Mochizuki's theorem aims to prove the important <a href="https://en.wikipedia.org/wiki/Abc_conjecture">abc conjecture</a>, which dates back to 1985 and relates to prime numbers.
<a href="https://www.newscientist.com/article/2099534-mathematicians-finally-starting-to-understand-epic-abc-proof/">The glimmer of understanding</a> that has started to emerge is well worth the effort, says [University of Nottingham's Ivan] Fesenko. "I expect that at least 100 of the most important open problems in number theory will be solved using Mochizuki's theory and further development." tag:metafilter.com,2016:site.161450Fri, 05 Aug 2016 17:35:03 -0800stinkfootDaddy can you multiply triples?
http://www.metafilter.com/161339/Daddy%2Dcan%2Dyou%2Dmultiply%2Dtriples
A group of Science YouTubers got together to perform <a href="https://www.youtube.com/watch?v=SZXHoWwBcDc">a tribute to a scientist Hamilton, in the style of his political musical namesake</a>. tag:metafilter.com,2016:site.161339Mon, 01 Aug 2016 05:24:02 -0800divabatSo, the unknowable kicks in
http://www.metafilter.com/161308/So%2Dthe%2Dunknowable%2Dkicks%2Din
<a href="https://plus.google.com/117663015413546257905/posts/VdJyWda2hrj">Logic hacking</a> - "Writing shorter and shorter computer programs for which it's unknowable whether these programs run forever, or stop... the winner of the <a href="https://johncarlosbaez.wordpress.com/2016/05/21/the-busy-beaver-game/">Busy Beaver Game</a> for N-state Turing machines becomes unknowable using ordinary math - somewhere between N = 5 and N = 1919." <a href="https://plus.google.com/117663015413546257905/posts/8eYTjrpiGte">Interview with a Mathematical Physicist</a>: <a href="https://plus.google.com/117663015413546257905/posts/JFF1nW6uxcD">John Baez</a>
<ul><li><a href="https://www.physicsforums.com/insights/interview-mathematical-physicist-john-baez-part-1/">Part 1</a> - "Here's the first part of an interview. I used it as an excuse to say what I've been doing all these years. I also talk about my uncle Albert Baez, who got me interested in physics in the first place - and <a href="https://johncarlosbaez.wordpress.com/2016/06/11/azimuth-news-part-5/">what I'm working on</a> right now. I hope it's interesting even if you care more about math and physics. There's a lot here about quantum gravity, category theory and some of my hobbies, like the octonions."</li>
<li><a href="https://www.physicsforums.com/insights/interview-mathematical-physicist-john-baez-part-2/">From crackpots to climate change</a> - "Here's part two of my interview on Physics Forums. I talk about the early days of the internet, before the world-web caught on. First we started discussing physics on 'usenet newsgroups' like sci.physics - but then a flood of crackpots invaded... That's what led me to create the Crackpot Index. But spending lots of time on newsgroups was still worthwhile, and it led me to start writing '<a href="http://math.ucr.edu/home/baez/TWF.html">This Week's Finds</a>', which has been called the world's first blog, in 1993. I also talk about my physics and math heroes, what discoveries I'm most looking forward to, and why I switched to thinking about environmental problems. It was a great chance to ponder lots of things, including the far future of the Universe."</li></ul>
also btw...
-<a href="https://plus.google.com/117663015413546257905/posts/gvzrNKQqqnV">1+1 = 0</a>
-<a href="https://plus.google.com/117663015413546257905/posts/4fMBVQUhrDm">Computing the uncomputable</a>
-<a href="https://plus.google.com/117663015413546257905/posts/6jw8M2dxV9g">The inaccessible infinite</a>
-<a href="https://plus.google.com/117663015413546257905/posts/ZSb9MWjdKss">The longest G+ post I'll ever write</a>
-<a href="https://plus.google.com/117663015413546257905/posts/8E9ztrNUir7">The world's most long-winded proof</a>
-<a href="https://www.cs.auckland.ac.nz/~chaitin/summer.html">Paradoxes of randomness</a>
-<a href="http://lemire.me/blog/2016/05/23/the-surprising-cleverness-of-modern-compilers/">The surprising cleverness of modern compilers</a> tag:metafilter.com,2016:site.161308Sat, 30 Jul 2016 11:42:28 -0800kliulessLet's hope they're friendly
http://www.metafilter.com/159676/Lets%2Dhope%2Dtheyre%2Dfriendly
<a href="http://cosmicawareness.com/books-audio-video/by-author/bruce-cathie/">Bruce Leonard Cathie</a> (1930–2013) <small>[<a href="https://en.wikipedia.org/wiki/Bruce_Cathie">Wikipedia</a>; <a href="http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10888656">obituary</a>]</small> was a pilot for the New Zealand <a href="http://www.radionz.co.nz/national/programmes/afternoons/galleries/nac">National Airways Corporation</a>. After a mysterious <a href="http://www.bibliotecapleyades.net/ciencia/ciencia_harmonicconquestspace_b.htm">aerial encounter</a> in 1952, he spent decades plotting UFO sightings, <a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig02.htm#5.- THE MYSTERIOUS AERIALS">scrutinising ham radio</a> operators, and developing an esoteric <a href="http://divinecosmos.com/start-here/books-free-online/18-the-shift-of-the-ages/65-the-shift-of-the-ages-chapter-09-the-cathie-grid">theory of reality</a> involving <a href="http://www.whale.to/m/cathie.html">UFOs</a>, a regular <a href="https://www.youtube.com/watch?v=6Fdg8fgvHbI">worldwide grid system</a>, <a href="https://youtu.be/3i5YHvneHls?t=118">anti-gravity</a> <small>[content advisory: gratuitous use of Matrix soundtrack]</small>, complex <a href="https://www.youtube.com/watch?v=MRc4vKwf3WA">mathematics</a>, and the geometric properties of <a href="https://www.youtube.com/watch?v=MctQ4Z4P45c">atomic bomb detonations</a>. Cathie elaborated his theories in a series of books, starting with <i>Harmonic 33</i> (1968), which inevitably found their way into the <a href="http://www.metafilter.com/159393/Mayan-constellations-map-to-Mayan-cities-helping-find-a-new-one#6517619">hands of high school students</a> around the world. In the late 1990s, he updated his earlier books, <i>Harmonic 695</i> and <i>The Pulse of the Universe, Harmonic 288</i>, and <a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig.htm">placed them online</a>. Some highlights from the combined manuscript include the following chapters:
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig01.htm#INTRODUCTION">Introduction</a>
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig01.htm#1.- THE BRANCHING AREAS FOR INVESTIGATION">1: The Branching Areas for Investigation</a>
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig01.htm#2.- MATHEMATICS OF THE WORLD GRID">2: Mathematics of the World Grid</a>
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig01.htm#4.- FURTHER EVIDENCE OF THE UFO GRID">4: Further Evidence of the UFO Grid</a>
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig02.htm#5.- THE MYSTERIOUS AERIALS">5: The Mysterious Aerials</a> [ham radio operators and the UFO grid].
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig02.htm#10.- THE MAPS OF THE ANCIENTS">10: The Maps of the Ancients</a>
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig03.htm#14.- WHERE HAVE ALL THE FLYERS GONE">14: Where Have All the Flyers Gone?</a> [Explaining the Bermuda Triangle using the World Grid System]
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig03.htm#15.- PEOPLE WE WOULD LIKE TO KNOW MORE ABOUT">15: People We Would Like to Know More About</a> [Cathie's firsthand accounts of run-ins with spies and mysterious entities]
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig04.htm#20.- THERE IS SOMETHING IN THE AIR">20: There Is Something in the Air</a> [New Zealand UFO sightings]
<a href="http://www.bibliotecapleyades.net/ciencia/energygrid_harmonic695/energygrig05.htm#29.- WAKE UP, EARTH!">29: Wake up, Earth!</a>
Two long lectures presented by Cathie, recorded in the late 1980s, have been uploaded to YouTube: <a href="https://www.youtube.com/watch?v=p5nWiP7SN3o">Part 1</a> (1 hr 14); <a href="https://www.youtube.com/watch?v=eFe64sPCt3Y">Part 2</a> (1 hr 22), in which Cathie freely discusses CIA involvement, atomic testing, UFO sightings, harmonics, the artificial nature of the moon, lost technologies of the ancients, and more. Cathie's interviews continue to <a href="https://www.youtube.com/watch?v=8kV81m6y_RE">provide grist</a> for number conspiracy theorists on YouTube. <small>[Advisories: introductory mullet, old-school Kiwi accent, home-made graphics, Tesla conspiracies]</small>
A <a href="http://www.worldgrid.net/about-bruce-cathie/">collaboration</a> with Oklahoma-based architect Rod Maupin enabled Cathie to map the world grid system using early forms of GIS, culminating in the <a href="http://www.worldgrid.net/introduction-to-the-world-grid/">World Grid</a> website, which attempts to relate the positioning of various facilities (nuclear power plants; particle accelerators) onto the grid:
<blockquote>... a computer program has been produced which carries out all the required calculations related to the light, gravity and earth magnetic field values. It has been found that many ancient building sites such as Stonehenge, the Great Pyramid, etc., show relationships with this unified harmonic mathematical system and indicates that the knowledge is not new. The civilizations at these times must have had scientific knowledge of a highly advanced nature.
We are now in the process of relearning this lost science. If the discovered harmonic unified equations can eventually be accepted by the scientific community as correct, then we may be on the threshold of true space travel which has no barriers. The equations show that light speed is not a constant and that time itself is a variable. Under these conditions there is no place out there in space that we cannot reach. Obviously, there is more mathematical knowledge to be discovered, but it appears that the code has been broken. Soon, with a bit of luck, we on Earth may have the chance to join our neighbours out there in the vast blackness of space.</blockquote>
******************
Cathie's work did not emerge from a vacuum. New Zealand has <a href="http://www.canterbury.ac.nz/southern-spirits/community/nz.shtml">traditionally had</a> thriving <a href="http://nzetc.victoria.ac.nz/tm/scholarly/tei-StaMaor-t1-body-d7.html">communities grounded</a> in alternative spirituality and the pursuit of esoteric knowledge.
In 1978, an Australian TV crew <a href="https://www.youtube.com/watch?v=5hNmg-fXcvs">succeeded in</a> capturing <a href="https://www.youtube.com/watch?v=dl0ZO4VbpoE">footage</a> of <a href="https://www.youtube.com/watch?v=SCV1_qUXg6g">UFOs</a> off the coast of Kaikoura, in New Zealand's South Island, a sighting that evidently <a href="https://www.youtube.com/watch?v=Fh45k2cREew">remains unexplained</a> despite sceptics who deploy phrases such as "squid boat lights," "camera shake," and "the planet Jupiter."
New Zealand and Australia were also prominent locations in the <a href="http://airminded.org/archives/mystery-aircraft/">mystery aircraft</a> phenomenon of the late nineteenth and early twentieth centuries, as chronicled by Australian historian Brett Holman: <a href="http://airminded.org/2010/10/20/scareships-over-australia-i/">part 1</a>, <a href="http://airminded.org/2010/10/23/scareships-over-australia-ii/">part 2</a>, <a href="http://airminded.org/2010/10/25/scareships-over-australia-iii-2/">part 3</a>, <a href="http://airminded.org/2010/10/27/scareships-over-australia-iv/">part 4</a>; <a href="https://www.academia.edu/3059379/Dreaming_war_airmindedness_and_the_Australian_mystery_aeroplane_scare_of_1918">updated version</a> subsequently published in <i>History Australia</i>.
Vintage New Zealand <a href="http://www.ufocusnz.org.nz/content/Aviation/80.aspx">aviation UFO sightings</a> from the Cathie era are now archived on the Ufocus New Zealand site, based on original versions taken from New Zealand Defence Force files and <a href="http://www.telegraph.co.uk/news/newstopics/howaboutthat/ufo/8221227/New-Zealand-releases-UFO-files.html">declassified in 2010</a>. (Here is Wellington City Library's <a href="https://www.flickr.com/photos/wellington-city-libraries/sets/72157625536135503/">complete set</a>, with readers in situ.) The full text of the NZDF's reports can be found <a href="https://archive.org/details/NewZealandUFO">here</a>, via archive.org. tag:metafilter.com,2016:site.159676Wed, 18 May 2016 14:15:28 -0800Sonny JimPhysics, math and science toys
http://www.metafilter.com/158448/Physics%2Dmath%2Dand%2Dscience%2Dtoys
<a href="https://www.instagram.com/physicsfun/">Physics Fun</a> is an Instagram account with short videos of physics, math and science 'toys.' An accompanying <a href="http://physicstoys.blogspot.com/">blog</a> looks at some in more detail. tag:metafilter.com,2016:site.158448Fri, 08 Apr 2016 09:57:52 -0800carterNo, really, pi is wrong.
http://www.metafilter.com/157886/No%2Dreally%2Dpi%2Dis%2Dwrong
<a href="http://tauday.com/tau-manifesto">The Tau Manifesto</a> tag:metafilter.com,2016:site.157886Mon, 14 Mar 2016 09:49:17 -0800anotherpanacea"In short, they commuted but didn't associate."
http://www.metafilter.com/157882/In%2Dshort%2Dthey%2Dcommuted%2Dbut%2Ddidnt%2Dassociate
Happy π Day! And do you know what that means? Math puns <a href="https://atkinsbookshelf.wordpress.com/tag/funny-pi-puns/">today</a>! <a href="http://www.calculushumor.com/calculus-humor/math-puns">Every</a> <a href="http://www.dorkly.com/post/73134/math-puns-yall">day</a>! In <a href="http://aperiodical.com/2015/01/the-aperiodicals-best-maths-pun-of-2014-competition-the-results/">competitions</a>, even. Don't like puns? Try other forms of <a href="http://www.math.utah.edu/~cherk/mathjokes.html">math humor</a> (or <a href="http://www.businessinsider.com/13-math-jokes-that-every-mathematician-finds-absolutely-hilarious-2013-5">over-explain them to businesspeople</a>)! tag:metafilter.com,2016:site.157882Mon, 14 Mar 2016 05:35:56 -0800metaquarryHilary Putnam (1926-2016)
http://www.metafilter.com/157877/Hilary%2DPutnam%2D1926%2D2016
<a href="https://en.wikipedia.org/wiki/Hilary_Putnam">Hilary Putnam</a>, one of the most important analytic philosophers of the last hundred years, <a href="http://www.legacy.com/obituaries/bostonglobe/obituary.aspx?page=lifestory&pid=178040325">died today</a> from mesothelioma. Putnam made numerous significant contributions to philosophy, including contributions to <a href="http://ieas.unideb.hu/admin/file_2908.pdf">epistemology (pdf)</a>, <a href="http://baa.univpgri-palembang.ac.id/perpus-fkip/Perpustakaan/Perpus%20Cero/Filsafat/Filsafat%20Modern/Materialisme%20Modern.pdf#page=245">metaphysics (pdf)</a>, <a href="http://www.princeton.edu/~hhalvors/teaching/phi520_f2012/putnam1980.pdf">logic (pdf)</a>, <a href="http://www.sciencedirect.com/science/article/pii/0315086075901160">philosophy of mathematics (pdf)</a>, <a href="http://www.ninagierasimczuk.com/flt2013/wp-content/uploads/2013/01/Putnam_1965.pdf">philosophy of computation (pdf)</a>, <a href="https://mechanism.ucsd.edu/~bill/teaching/philsci/openheim.putnam.unity.pdf">philosophy of science (pdf)</a>, <a href="http://www.coli.uni-saarland.de/courses/lexsem09/material/u_boltz.pdf">philosophy of language (pdf)</a>, <a href="http://thatmarcusfamily.org/philosophy/Course_Websites/Math_S08/Readings/Putnam_MWF.pdf">philosophy of mathematics again (pdf)</a>, and <a href="http://www.phil.uu.nl/~joel/3027/3027PutnamPsychPredicates.pdf">philosophy of mind (pdf)</a>. (These are really only a small sampling of his contributions: ones that happen to be available online and that I could easily track down. They are mainly included here to indicate the breadth and scope of Putnam's philosophical work, while linking to his papers themselves, as opposed to second-hand reports.)
And here are some videos that show him in action or at least have recordings of his voice:
<a href="https://www.youtube.com/watch?v=et8kDNF_nEc">A younger Putnam interviewed by Bryan Magee on epistemology and the philosophy of science.</a>
<a href="https://www.youtube.com/watch?v=qMHtgrmpvYM">An older Putnam interviewed on a range of contemporary questions, including on the state of analytic philosophy today.</a>
<a href="https://www.youtube.com/watch?v=F2D3koWLyh8">Putnam at a roundtable discussion of externalism.</a>
<a href="https://www.youtube.com/watch?v=-1OESPPs68E">Putnam on naive realism and qualia.</a>
<a href="https://www.youtube.com/watch?v=wCTawI5hfEU">Putnam on the fact/value dichotomy.</a> tag:metafilter.com,2016:site.157877Sun, 13 Mar 2016 19:50:22 -0800Jonathan LivengoodWhen to stop dating and settle down, according to math
http://www.metafilter.com/157496/When%2Dto%2Dstop%2Ddating%2Dand%2Dsettle%2Ddown%2Daccording%2Dto%2Dmath
<a href="https://en.wikipedia.org/wiki/Optimal_stopping">Optimal stopping</a> is a <a href="http://www.americanscientist.org/issues/pub/knowing-when-to-stop">math theory</a> that can be used to solve <a href="http://www.inc.com/larry-kim/this-mathematical-formula-optimizes-success-in-life-love-amp-career.html">real world</a> decision problems. In the <a href="http://www.slate.com/articles/technology/technology/2014/12/the_secretary_problem_use_this_algorithm_to_determine_exactly_how_many_people.html">real world</a>, it is often applied to <a href="https://www.washingtonpost.com/news/wonk/wp/2016/02/16/when-to-stop-dating-and-settle-down-according-to-math/">help decide</a> when to <a href="http://rs.io/the-secretary-problem-explained-dating/">stop dating</a> and <a href="http://www.npr.org/sections/krulwich/2014/05/15/312537965/how-to-marry-the-right-girl-a-mathematical-solution">get married</a>. tag:metafilter.com,2016:site.157496Sun, 28 Feb 2016 08:27:19 -0800reenum"there are ten enthusiastic seconds in 6 weeks"
http://www.metafilter.com/157127/there%2Dare%2Dten%2Denthusiastic%2Dseconds%2Din%2D6%2Dweeks
<a href="https://www.reddit.com/r/AskReddit/comments/45m1zl/whats_the_coolest_mathematical_fact_you_know_of/">What is the coolest mathematical fact you know? (SLReddit)</a> tag:metafilter.com,2016:site.157127Sun, 14 Feb 2016 15:24:09 -0800holmesianMore kids more math
http://www.metafilter.com/156961/More%2Dkids%2Dmore%2Dmath
"You wouldn't see it in most classrooms, you wouldn't know it by looking at slumping national test-score averages, but a cadre of American teenagers are reaching world-class heights in math—more of them, more regularly, than ever before." Peg Tyre in <em>The Atlantic</em> covers <a href="http://www.theatlantic.com/magazine/archive/2016/03/the-math-revolution/426855/">the new wave of deeper, faster, and hopefully broader math education</a>. Featuring:
<a href="http://www.beammath.org/">Bridge to Enter Advanced Mathematics</a>, a program for low-income students in New York City;
<a href="https://www.imo-official.org/">The International Math Olympiad</a>, which the U.S. team <a href="http://www.maa.org/news/us-team-takes-first-place-at-international-mathematical-olympiad">won last summer</a> for the first time in more than 20 years;
<a href="https://www.mathcircles.org/">Math Circles</a> -- find one near you!
<a href="http://www.artofproblemsolving.com/">Art of Problem Solving</a>, a popular online math forum for math-loving kids;
<a href="http://www.proofschool.org/#we-love-math">Proof School</a>, the brand-new math-emphasis high school in San Francisco;
and too many more to link! tag:metafilter.com,2016:site.156961Mon, 08 Feb 2016 21:34:50 -0800escabeche156829? Mass-market. Tacky.
http://www.metafilter.com/156829/156829%2DMass%2Dmarket%2DTacky
<a href="http://www.neverendingbooks.org/artisanal-integers">Artisanal Integers</a> - <em>Summer of 2012. Suddenly several "integer-as-a-service-providers" spring from nowhere. They deliver "artisanal integers". Integers which (they claim) are "hand-crafted and guaranteed to be unique and hella-beautiful".</em> tag:metafilter.com,2016:site.156829Thu, 04 Feb 2016 04:34:56 -0800WolfdogBabylonian (Pre)Calculus!
http://www.metafilter.com/156701/Babylonian%2DPreCalculus
<a href="http://www.nytimes.com/2016/01/29/science/babylonians-clay-tablets-geometry-astronomy-jupiter.html">Signs of Modern Astronomy Seen in Ancient Babylon</a> - "Scientists have found a small clay tablet with markings indicating that a sort of precalculus technique was used to track Jupiter's motion in the night sky." also btw...
-<a href="http://www.npr.org/sections/thetwo-way/2016/01/28/464447490/track-jupiters-path-like-an-ancient-babylonian">Track Jupiter's Path Like An Ancient Babylonian</a>
-<a href="http://www.csmonitor.com/Science/2016/0128/Were-ancient-Babylonian-astronomers-math-whizzes-Check-the-tablets">Ancient Babylonian tablets describe the motion of Jupiter</a>
-<a href="http://www.sciencemag.org/news/2016/01/math-whizzes-ancient-babylon-figured-out-forerunner-calculus">Math whizzes of ancient Babylon figured out forerunner of calculus</a> (<a href="https://twitter.com/GaryMarcus/status/693131477320650752">via</a>)
-<a href="http://www.independent.co.uk/news/science/ancient-babylonians-used-early-calculus-to-track-path-of-jupiter-study-finds-a6840146.html">Ancient Babylonians used early calculus to track path of Jupiter</a>, <a href="http://science.sciencemag.org/content/351/6272/482.full">study finds</a>
more <a href="https://en.wikipedia.org/wiki/Babylonian_mathematics">Babylonian mathematics</a> :P
<a href="http://johncarlosbaez.wordpress.com/2011/12/02/babylon-and-the-square-root-of-2/">Babylon and the Square Root of 2</a> [<a href="https://plus.google.com/u/0/117663015413546257905/posts/UGJtj27dRZS">1</a>,<a href="https://plus.google.com/u/0/117663015413546257905/posts/M28exrNgUhY">2</a>,<a href="https://plus.google.com/u/0/117663015413546257905/posts/baH3euRS9Pf">3</a>]<a href="http://www.metafilter.com/115787/Sure-its-irrational-Just-look#4387486">*</a>
Astroarchaeology/Archaeoastronomy <a href="http://www.metafilter.com/19288/Archaeoastronomy">previously</a>... tag:metafilter.com,2016:site.156701Fri, 29 Jan 2016 13:01:20 -0800kliuless0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, ...
http://www.metafilter.com/156665/0%2D1%2D1%2D0%2D1%2D0%2D0%2D1%2D1%2D0%2D0%2D1%2D0%2D1%2D1%2D0
<a href="https://www.youtube.com/watch?v=prh72BLNjIk">Fair sharing,</a> the Thue-Morse sequence, infinitely long chess games, and related ideas. [A light, 10 minute video] tag:metafilter.com,2016:site.156665Thu, 28 Jan 2016 07:07:20 -0800WolfdogI'm a graph just like you
http://www.metafilter.com/156527/Im%2Da%2Dgraph%2Djust%2Dlike%2Dyou
<i>[In late 2015], László Babai, of the University of Chicago, announced that he had come up with a new algorithm for the "graph isomorphism" problem, <a href="https://www.quantamagazine.org/20151214-graph-isomorphism-algorithm/">one of the most tantalizing mysteries in computer science.</a></i> tag:metafilter.com,2016:site.156527Sun, 24 Jan 2016 06:19:05 -0800WolfdogI feel like I've finally gotten to know Ada Lovelace
http://www.metafilter.com/156365/I%2Dfeel%2Dlike%2DIve%2Dfinally%2Dgotten%2Dto%2Dknow%2DAda%2DLovelace
<a href="http://blog.stephenwolfram.com/2015/12/untangling-the-tale-of-ada-lovelace/">Untangling the Tale of Ada Lovelace</a> - by Stephen Wolfram; a good read, even if you're generally familiar with the story of Lovelace, Babbage, and the Difference Engine. tag:metafilter.com,2016:site.156365Tue, 19 Jan 2016 05:06:28 -0800WolfdogLet me tell you about the equilibrium of bodies...
http://www.metafilter.com/156237/Let%2Dme%2Dtell%2Dyou%2Dabout%2Dthe%2Dequilibrium%2Dof%2Dbodies
<em>Published in 1913, a best-seller in the 1930s and long out of print, </em><a href="https://archive.org/details/physicsforentert035428mbp">Physics for Entertainment</a> <em>was translated from Russian into many languages and influenced science students around the world ... In the foreword, the book's <a href="https://en.wikipedia.org/wiki/Yakov_Perelman">author</a> describes the contents as "conundrums, brain-teasers, entertaining anecdotes, and unexpected comparisons," adding, "I have quoted extensively from Jules Verne, H. G. Wells, Mark Twain and other writers, because, besides providing entertainment, the fantastic experiments these writers describe may well serve as instructive illustrations at physics classes."</em> tag:metafilter.com,2016:site.156237Wed, 13 Jan 2016 07:56:08 -0800WolfdogMaths and physics visualizations
http://www.metafilter.com/156174/Maths%2Dand%2Dphysics%2Dvisualizations
<a href="https://en.wikipedia.org/wiki/User:LucasVB/Gallery">Illustrations, diagrams, and animations,</a> many of maths and physics concepts, created for Wikipedia by <a href="http://1ucasvb.tumblr.com/about">Lucas Vieira Barbosa</a>. tag:metafilter.com,2016:site.156174Sat, 09 Jan 2016 17:42:47 -0800carterMemory, Law, and Recording
http://www.metafilter.com/156012/Memory%2DLaw%2Dand%2DRecording
Sci-Fi Author (and<a href="http://www.metafilter.com/user/20966"> Metafilter's own</a>) Charlie Stross has an interesting thought experiment:<a href="http://www.antipope.org/charlie/blog-static/2016/01/a-world-building-puzzler.html"> Could you get to a technological society without the use of writing? And if so, what would that look like?</a> tag:metafilter.com,2016:site.156012Sun, 03 Jan 2016 06:46:36 -0800The WhelkThe emperor was naked, and so is this.
http://www.metafilter.com/155378/The%2Demperor%2Dwas%2Dnaked%2Dand%2Dso%2Dis%2Dthis
<em>"Respected research math is dominated by men of a certain attitude. Even allowing for individual variation, there is still a tendency towards an oppressive atmosphere, which is carefully maintained and even championed by those who find it conducive to success."</em> Recent Princeton graduate Piper Harron's PhD thesis isn't written for these men. It is very cool number theory, and <a href="http://www.theliberatedmathematician.com/wp-content/uploads/2015/11/PiperThesisPostPrint.pdf">it is art.</a> tag:metafilter.com,2015:site.155378Tue, 08 Dec 2015 21:24:32 -0800bergamot and vetiverThe word algorithm derives from his name.
http://www.metafilter.com/154512/The%2Dword%2Dalgorithm%2Dderives%2Dfrom%2Dhis%2Dname
The <a href="http://www.khwarizmi.org/pages/muhammad-bin-musa-al-khwarizmi">word</a> algebra <a href="https://www.youtube.com/watch?v=xkAQDEhmPYc">stems</a> from the Arabic word al-jabr, which has its <a href="http://www.storyofmathematics.com/islamic_alkhwarizmi.html">roots</a> in the title of a 9th century manuscript <a href="http://profkeithdevlin.org/tag/algebra/">written</a> by the <a href="http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Al-Khwarizmi.html">mathematician</a> Al-Khwarizmi. The <em>Kitab al-mukhtasar fi <a href="http://www.wdl.org/en/item/7462/">hisab al-jabr</a> wal-muqabala</em> (The <a href="http://www.wilbourhall.org/pdfs/mbp/robertofchesters00khuw.pdf">Compendious Book on Calculation</a> by Completion and Balancing) was a <a href="http://www.famousscientists.org/muhammad-ibn-musa-al-khwarizmi/">pioneering</a> piece of work - offering practical answers for land distribution, rules on inheritance and distributing salaries. This treatise also <a href="http://www.muslimheritage.com/article/contribution-al-khwarizmi-mathematics-and-geography">underpins</a> the science of flight and the engineering <a href="http://gulfnews.com/culture/people/the-father-of-algebra-abu-jaafar-mohammad-ibn-mousa-al-khwarizmi-1.1233076">behind</a> the fastest car in the world. <a href="http://www.aljazeera.com/programmes/science-in-a-golden-age/2015/10/al-khwarizmi-father-algebra-151019144853758.html">via</a> tag:metafilter.com,2015:site.154512Sat, 07 Nov 2015 04:28:31 -0800infini