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Washington Driver's License Numbers

2010 Feb 24, 12:42Apparently Washington State uses an algorithm to generate drivers license numbers. Unless someone else has the same name and birth date your license number is based entirely on your name and birth date.PermalinkCommentsmath identity washington reference

Google and China: the attacks and their aftermath

2010 Jan 13, 6:35Ars Technica rounds up links on the recent Google threatening to stop censoring itself in China including quotes from Secretary of State Clinton, and the EFF and info on the hacks.PermalinkCommentsgoogle china arstechnica news politics security censorship

The Kickstarter Blog - The Mysterious Letters Aftermath

2009 Dec 8, 8:45"And then there’s Mysterious Letters, a Kickstarter project from two artists — Michael and Lenka — to mail everyone in the world a personal letter. It began in April with a small village named Cushendall in Northern Ireland, where the letters caused quite a stir"PermalinkCommentshumor art letter mail

linkiblog | How to Build a Popularity Algorithm You can be Proud of

2009 Sep 9, 5:49PermalinkCommentstechnical statistics algorithms howto social tutorial math popular reddit digg programming

WHEN ZOMBIES ATTACK!: MATHEMATICAL MODELLING OF AN OUTBREAK OF ZOMBIE INFECTION

2009 Aug 25, 7:10Research paper modelling zombie infection. "The key difference between the models presented here and other models of infectious disease is that the dead can come back to life." Also, love the references section with "Snyder, Zack (director), 2004 Dawn of the Dead" next to things like "Bainov, D.D. & Simeonov, P.S. Impulsive Differential Equations: Asymptotic Properties of the Solutions. World Scientific, Singapore (1995)."PermalinkCommentshumor zombie research via:schneier math science health apocalypse system:filetype:pdf system:media:document

DSpace@MIT : Parallel and Distributed Computation:Numerical Methods

2009 Jul 27, 5:27"Parallel and Distributed Computation:Numerical Methods", Bertsekas, Dimitri P.; Tsitsiklis, John N., 2003-11-21PermalinkCommentsprogramming mit pdf algorithm distributed parallel math todo technical

SCIENCE SCOUTS

2009 Jun 11, 3:16Humorous science merit badges. "The 'I build robots' badge (LEVEL IV): In which, technically technically, the recipient is not in the business of world domination (as dictated by membership rules), but has built a robot that is.", "The 'non-explainer' badge (LEVEL I): Where the recipient can no longer explain what they do to their parents", And other humorous badges.PermalinkCommentshumor web science math nerd badge via:boingboing

Platonic Ideals in Anathem and The Atrocity Archives

2009 Apr 7, 11:58
The Atrocity ArchivesThe Jennifer MorgueAnathem

This past week I finished Anathem and despite the intimidating physical size of the book (difficult to take and read on the bus) I became very engrossed and was able to finish it in several orders of magnitude less time than what I spent on the Baroque Cycle. Whereas reading the Baroque Cycle you can imagine Neal Stephenson sifting through giant economic tomes (or at least that's where my mind went whenever the characters began to explain macro-economics to one another), in Anathem you can see Neal Stephenson staying up late pouring over philosophy of mathematics. When not exploring philosophy, Anathem has an appropriate amount of humor, love interests, nuclear bombs, etc. as you might hope from reading Snow Crash or Diamond Age. I thoroughly enjoyed Anathem.

On the topic of made up words: I get made up words for made up things, but there's already a name for cell-phone in English: its "cell-phone". The narrator notes that the book has been translated into English so I guess I'll blame the fictional translator. Anyway, I wasn't bothered by the made up words nearly as much as some folk. Its a good thing I'm long out of college because I can easily imagine confusing the names of actual concepts and people with those from the book, like Hemn space for Hamming distance. Towards the beginning, the description of slines and the post-post-apocalyptic setting reminded me briefly of Idiocracy.

Recently, I've been reading everything of Charles Stross that I can, including about a month ago, The Jennifer Morgue from the surprisingly awesome amalgamation genre of spy thriller and Lovecraft horror. Its the second in a series set in a universe in which magic exists as a form of mathematics and follows Bob Howard programmer/hacker, cube dweller, and begrudging spy who works for a government agency tasked to suppress this knowledge and protect the world from its use. For a taste, try a short story from the series that's freely available on Tor's website, Down on the Farm.

Coincidentally, both Anathem and the Bob Howard series take an interest in the world of Platonic ideals. In the case of Anathem (without spoiling anything) the universe of Platonic ideals, under a different name of course, is debated by the characters to be either just a concept or an actual separate universe and later becomes the underpinning of major events in the book. In the Bob Howard series, magic is applied mathematics that through particular proofs or computations awakens/disturbs/provokes unnamed horrors in the universe of Platonic ideals to produce some desired effect in Bob's universe.

PermalinkCommentsatrocity archives neal stephenson jennifer morgue plato bob howard anathem

YouTube - Mathnet - Case of the Willing Parrot (Recap & Finale) Pt.1

2009 Jan 7, 6:18Mathnet, yes! Square One was great!PermalinkCommentsvia:swannman math mathnet tv video youtube parrot pbs

Evil Mad Scientist Laboratories - Binary Birthday

2008 Nov 19, 4:28"A binary birthday candle. It consists of a single candle with seven wicks, where the wicks that are lit represent the birthday individual's age in binary. This single candle design works flawlessly to represent any age from 1 to 127, never requiring anyone below the age of 127 to blow out more than a mere six candles at a time."PermalinkCommentsvia:swannman birthday geek math humor howto cake birthday-cake candle binary

9NEWS.com | Colorado's Online News Leader | Three small canisters ...

2008 Nov 11, 3:57Grandpa's old films contain some surprises: "There was another reason why the Library of Congress wanted the original films. They are a treasure trove of historic video of the aftermath of D-Day."PermalinkCommentsvideo history library-of-congress

The igraph library for complex network research

2008 Nov 5, 3:55A graphing library which includes variaous graph visualization algorithms. GNU licensed. "igraph is a free software package for creating and manipulating undirected and directed graphs. It includes implementations for classic graph theory problems like minimum spanning trees and network flow, and also implements algorithms for some recent network analysis methods, like community structure search."PermalinkCommentsreference free development programming visualization graph math library opensource c++ igraph graphviz via:mattb

Amazon.com: A Million Random Digits with 100,000 Normal Deviates: RAND Corporation: Books

2008 Oct 31, 7:10Bruce Schneier pointed out this book: "A Million Random Digits with 100,000 Normal Deviates (Paperback)". Its 600 pages of random numbers. I'd get a copy if it didn't cost $90! From the stats page Amazon lists the 100 most used words in the book: "6 8 11 19 23 28 30 32 37 38 42 47 52 54 56 60 72 77 80 84 86 92 101 102 107 108 111 115 125 126 131 143 147 148 150 157 158 163 166 167 171 179 183 188 190 197 206 207 212 215 218 220 226 228 230 234 236 242 247 249 251 253 261 265 272 292 297 304 311 323 332 336 337 338 344 345 354 356 358 359 364 371 372 374 384 389 391 409 412 413 421 433 436 443 457 481 489 516 517 642"PermalinkCommentsvia:schneier random book humor math csc

xkcd - Blog Archive - The Goddamn Airplane on the Goddamn Treadmill

2008 Oct 10, 1:32Xkcd providing answers to questions that I forgot I had, like what is the answer to the lawn-sprinkler question from Surely You're Joking Mr. Feynman. "Feynman used to tell a story about a simple lawn-sprinkler physics problem. The nifty thing about the problem was that the answer was immediately obvious, but to some people it was immediately obvious one way and to some it was immediately obvious the other. (For the record, the answer to Feynman problem, which he never tells you in his book, was that the sprinkler doesn't move at all. Moreover, he only brought it up to start an argument to act as a diversion while he seduced your mother in the other room.)"PermalinkCommentshumor feynman comic blog xkcd physics science math

rec.arts.sf.science qdFAQ

2008 Aug 26, 3:42Links to write ups on how much energy it would take to destroy the Earth or at least make it inhabitable in various fashions: "Destroying the Earth, It is often asked what it would take to shatter the Earth into little pieces. Erik Max Francis gives a rough answer. A less drastic measure would be to sterilise it by heating the outside. Brian Davis does the arithmetic, but I think he should have calculated what it would take to boil the oceans, which is a few thousand times more by my BotEC. Occasionally it is asked what would happen if you shot a fast-moving projectile at the Earth; I've written something up."PermalinkCommentsscifi science math

Deriving a Non-Recursive Fibonacci Function Using Linear Algebra

2008 Aug 20, 10:51

In my Intro to Algorithms course in college the Fibonacci sequence was used as the example algorithm to which various types of algorithm creation methods were applied. As the course went on we made better and better performing algorithms to find the nth Fibonacci number. In another course we were told about a matrix that when multiplied successively produced Fibonacci numbers. In my linear algebra courses I realized I could diagonalize the matrix to find a non-recursive Fibonacci function. To my surprise this worked and I found a function.
The Nth Fibonacci value is (1 + sqrt(5))^N - (1 - sqrt(5))^N all over sqrt(5) * 2^N
Looking online I found that of course this same function was already well known. Mostly I was irritated that after all the algorithms we created for faster and faster Fibonacci functions we were never told about a constant time function like this.

I recently found my paper depicting this and thought it would be a good thing to use to try out MathML, a markup language for displaying math. I went to the MathML implementations page and installed a plugin for IE to display MathML and then began writing up my paper in MathML. I wrote the MathML by hand and must say that's not how its intended to be created. The language is very verbose and it took me a long time to get the page of equations transcribed.

MathML has presentation elements and content elements that can be used separately or together. I stuck to content elements and while it looked great in IE with my extension when I tried it in FireFox which has builtin MathML support it didn't render. As it turns out FireFox doesn't support MathML content elements. I had already finished creating this page by hand and wasn't about to switch to content elements. Also, in order to get IE to render a MathML document, the document needs directives at the top for specific IE extensions which is a pain. Thankfully, the W3C has a MathML cross platform stylesheet. You just include this XSL at the top of your XHTML page and it turns content elements into appropriate presentation elements, and inserts all the known IE extension goo required for you. So now my page can look lovely and all the ickiness to get it to render is contained in the W3C's XSL.

PermalinkCommentstechnical mathml fibonacci math

BBC NEWS | UK | Payout for false Facebook profile

2008 Jul 24, 7:26Fake Facebook page considered libel and gets target big pounds: "Mathew Firsht was awarded 22,000 pounds in damages against an old school friend". Careful what you post...PermalinkCommentsfacebook identity law legal privacy libel

Tor.com / Science fiction and fantasy / Stories / Down on the Farm by Charles Stross

2008 Jul 22, 5:17Down on the Farm by Charles Stross. Short scifi story with elements of steampunk and a math/csc based version of the occult.PermalinkCommentsmath scifi fiction free tor literature charles-stross

Math: It's Delicious! | Militant Geek Custom Shirts

2008 Jun 19, 11:24"Math is delicious" tshirt.PermalinkCommentstshirt shirt purchase product math humor awesome

Zeno's Progress Bar - Stolen Thoughts

2008 Apr 7, 10:09

Text-less progress bar dialog. Licensed under Creative Commons by Ian HamptonMore of my thoughts have been stolen: In my previous job the customer wanted a progress bar displayed while information was copied off of proprietary hardware, during which the software didn't get any indication of progress until the copy was finished. I joked (mostly) that we could display a progress bar that continuously slows down and never quite reaches the end until we know we're done getting info from the hardware. The amount of progress would be a function of time where as time approaches infinity, progress approaches a value of at most 100 percent.

This is similar to Zeno's Paradox which says you can't cross a room because to do so first you must cross half the room, then you must cross half the remaining distance, then half the remaining again, and so on which means you must take an infinite number of steps. There's also an old joke inspired by Zeno's Paradox. The joke is the prototypical engineering vs sciences joke and is moderately humorous, but I think the fact that Wolfram has an interactive applet demonstrating the joke is funnier than the joke itself.

I recently found Lou Franco's blog post "Using Zeno's Paradox For Progress Bars" which covers the same concept as Zeno's Progress Bar but with real code. Apparently Lou wasn't making a joke and actually used this progress bar in an application. A progress bar that doesn't accurately represent progress seems dishonest. In cases like the Vista Defrag where the software can't make a reasonable guess about how long a process will take the software shouldn't display a progress bar.

Similarly a paper by Chris Harrison "Rethinking the Progress Bar" suggests that if a progress bar speeds up towards the end the user will perceive the operation as taking less time. The paper is interesting, but as in the previous case, I'd rather have progress accurately represented even if it means the user doesn't perceive the operation as being as fast.

Update: I should be clearer about Lou's post. He was actually making a practical and implementable suggestion as to how to handle the case of displaying progress when you have some idea of how long it will take but no indications of progress, whereas my suggestion is impractical and more of a joke concerning displaying progress with no indication of progress nor a general idea of how long it will take.

PermalinkCommentszenos paradox technical stolen-thoughts boring progress zeno software math
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