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Major Advances In Knot Theory

An anonymous reader sends us to Science News, which is running a survey of recent strides in finding an answer to the age-old question: How many ways are there to tie your shoelaces? "Mathematicians have been puzzling over that question for a century or two, and the main thing they've discovered is that the question is really, really hard. In the last decade, though, they've developed some powerful new tools inspired by physics that have pried a few answers from the universe's clutches. Even more exciting is that the new tools seem to be the tip of a much larger theory that mathematicians are just beginning to uncover. That larger mathematical theory, if it exists, may help crack some of the hardest mathematical questions there are, questions about the mathematical structure of the three- and four-dimensional space where we live. ... Revealing the full ... superstructure may be the work of a generation."

12 of 230 comments (clear)

  1. An easy answer by $0.02 · · Score: 5, Funny

    How many ways are there to tie your shoelaces? The answer is very easy ... knot.

    --
    If enithin kan gow rong it whil. (Murfey)
  2. !theory by russlar · · Score: 5, Funny

    So, can we abbreviate this "knot theory" to "!theory"?

    --
    Anybody want my mod points?
  3. The 85 Ways to Tie a Tie by perlstar · · Score: 5, Informative

    Man, I haven't posted in years... but there's a great book by this title written by two mathematicians. They talk about the topology of knots as well as the history of ties. Which actors/celebrities wore what tie knots, etc.

    I can't seem to locate my copy at the moment, but from what I recall, there are an infinite number of potential knots, but they are classified by the number of sequences in them. And within a certain number of steps, (I think 5) there are 85 possible ways to tie a tie. Then they rank them by symmetry and a copule other criteria.

    I recommend it to anybody who is interested in this subject. It's out of print, but it's still possible to find a copy for sale online.

  4. Re:This is so very important... by ScentCone · · Score: 5, Insightful

    I can't believe I got moderated as a troll

    Why? You made a whiny, irrelevent complaint that dismisses the role of pure research in the larger advancement of our knowledge of how the universe works... the very sort of thing that always plays a role in advancing our ability to make more efficient use of energy, more realistic predictions about the behavior of complex systems, and more innovative technological use of things we think we have already fully, or most effectly exploited. This whole "the human race is incapable of doing two things at once" BS never ceases to amaze me. How do you even get out of bed in the morning? Make coffee... take a crap... which to do first? Gaah! I'm paralyzed! Which is the most important fish to fry?

    In other words, you're scare mongering and - if we can assume you have a passable IQ which would suggest you might know better - clearly trolling. And, voila, you were thusly modded.

    --
    Don't disappoint your bird dog. Go to the range.
  5. Re:This is so very important... by Evanisincontrol · · Score: 5, Insightful

    Suppose you tell us all how solving this knotty problem will help anyone or anything.

    Let's pretend we're in the early 1700s. Leonhard Euler is writing the first ever paper on a field of study called Graph Theory. Simply put, he's figuring out answers to questions about how to arrange circles and lines. Meanwhile, there's fucking WARS going on (Polish succession is going on concurrent to writing this paper; Seven Years' war happens a couple decades later). There are goddamn wars on Euler's front door, and he's writing papers about lines and circles?! What a prick.

    Oh, by the way, without Euler's work we wouldn't have computers, organized roads, efficient data models, efficient sorting algorithms, or countless other instruments that are critical to today's society.

    Don't trivialize work that you don't understand.

  6. Re:This is so very important... by msuarezalvarez · · Score: 5, Funny

    Let me introduce you to ^W.

    It's a great tool for those writing pseudo-ironic posts who are, at the same time, concerned with the preservation of the valuable resource of ones and zeroes...

  7. Can There Be a Knot that Cannot Be Tied or Untied? by Louis+Savain · · Score: 5, Funny

    I'm just wondering. One never knows with math.

  8. wrong theory by Better.Safe.Than.Sor · · Score: 5, Funny

    I prefer the "velcro" theory.

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    It's all history, man. -anon
  9. Re:How many ways are there to tie your shoelaces? by gsgriffin · · Score: 5, Funny

    Its actually 84. You forgot that you can always double-knot each of them too.

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    jsut athnoer menagiensls ltitle psrhae for you to dcoede. Why do we wtsae our tmie dnoig tihs?
  10. Re:Things like this... by DG · · Score: 5, Interesting

    Back when I was going to school for my Comp Sci degree, I was force-fed a lot of calculus.

    Roughly twice as much calculus as was typical, because my disinterest (and the resultant lack of success) required me to take almost every single calculus course twice.

    No sooner was I free of school than I brain-dumped every single last integral, deriviative, partial derivative, chain rule, trigometric identity... the lot of it. Good riddance to bad rubbish.

    And then, some time later, I was trying to make my race car go faster. The problem was optimising the suspension for maximum grip, and to that end, I had affixed linear potentiometers to my suspension so I could record suspension position during a race.

    Pretty soon, I had tons of data relating position to time. Pretty graphs, but aside from max/min/mean deflection data, pretty useless.

    Until I started thinking about "position to time... position to time... where had I heard that before?"

    That's right - my old arch-nemesis, calculus, suddenly proved useful. Deriving that position information gave me suspension velocity, and suddenly I knew EXACTLY what suspension velocities the car was seeing in actual competition. Given that I had a device that measured shock force as a function of velocity (that's how a shock works) I could now tune shocks independant of the driver's ass-dyno.

    That resulted in a HUGE leap forward in my performance.

    Don't dis abstract math - you never know when it'll pay off.

    DG

    --
    Want to learn about race cars? Read my Book
  11. Re:Things like this... by Anonymous Coward · · Score: 5, Funny

    Back when I was going to school for my Elementary School diploma, I was force-fed a lot of arithmetic.

    Roughly twice as much as was typical, because my disinterest (and the resultant lack of success) required me to take almost every grade twice.

    No sooner was I free of school than I brain-dumped every single addition, multiplication, subtraction, division, counting... the lot of it. Good riddance to bad rubbish.

    And then, some time later, I was trying to make my paycheck go farther. The problem was optimising the spending for maximum personal happiness, and to that end, I had collected all of my receipts so that I could record where I was spending my money during the month.

    Pretty soon, I had tons of data indicating where my money was going. Pretty numbers, but aside from a few expensive items, pretty useless.

    Until I started thinking about what I could do with a set of numbers.

    That's right - my old arch-nemesis, arithmetic, suddenly proved useful. Summing the money spent in different categories gave me totals, and suddenly I knew EXACTLY where my money was going in an actual month. Given that I had measured how much money was spent on each purchase (that's how receipts work) I could now properly budget my spending.

    That resulted in a HUGE leap forward in my quality of life.

    Don't dis abstract math - you never know when it'll pay off.

    AC

  12. Re:Unless... by Anonymous Coward · · Score: 5, Insightful

    No. As a professional computer scientist, I think it is safe to say mathematicians are about the last people in the world to be in danger of losing their job to computers.

    If there's one thing computer science algorithmic theory has told us, it's that computers absolutely do have a limit on what they can do, no matter how fast the microchip gets. Complete searches (and that is what we're talking for computer proofs) are NOT getting any more feasible over time. 2^10000 branches will never be traversable.

    Pretty much the best possible scenario for computer proofs is basic geometry. After all, in US high school, students are taught "2-column" proofs that a computer could actually handle. And even here, computers suck compared to mediocre mathematicians. Why? Because anybody can trace basic implications like a computer does - that's the easy part. The ONLY real hard part is the flash of insight that computers can never do - e.g. why don't we consider this point that is only tangentially related and see how it somehow holds all the structure to solving the problem.

    Once you get into modern math, say knot theory, computers are completely hosed. A math paper might be 100 pages of prose, 80% of which might be insights like that thing above, and 20% of which might be basic implications that a computer can handle. And actually, it couldn't, because 20 pages in prose = 2000 pages in logic statements, and a computer will never be able to traverse that deep.

    There's a reason that every important computer proof up until now has relied on 0 insight from the computer... even something like the 4-color theorem is only using a computer to algorithmically check a finite number of trivial cases that would be impractical to check by hand. This approach does not generalize to making mathematicians obsolete.