[HN Gopher] Graduate Student Solves Decades-Old Conway Knot Problem
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       Graduate Student Solves Decades-Old Conway Knot Problem
        
       Author : theafh
       Score  : 240 points
       Date   : 2020-05-19 16:17 UTC (6 hours ago)
        
 (HTM) web link (www.quantamagazine.org)
 (TXT) w3m dump (www.quantamagazine.org)
        
       | JoeAltmaier wrote:
       | This story will go down in mathematical history. A graduate
       | student attacks an old unsolved problem, in her spare time, shows
       | up with the solution a week later. Invents a new approach to
       | topology in the process.
        
         | hypersoar wrote:
         | It's been known to happen. Would that all of our Ph.D.s were
         | that easy.
        
         | high_derivative wrote:
         | I wonder how much it helped the creative flow to not know it
         | was an allegedly unsolvable problem. No fear to fail, no
         | stress, not the feeling something complex might be needed
         | because everything simple was already tried.
        
           | exmadscientist wrote:
           | And in addition, it wasn't (quite) her field. (This shows
           | somewhat in the paper linked elsewhere in the comments: you
           | can kind of see the two different jargons in use.) The power
           | of fresh eyes is often underestimated.
        
             | cosmie wrote:
             | This. I've built my career off of diversity of experience -
             | changing both the industry and functional role I work in
             | almost every time I change companies.
             | 
             | It's amazing how impactful it can be to take an industry-
             | naive approach to a problem/project. A lot of disciplines
             | have fundamentally similar challenges, but with solutions
             | that evolved in completely different directions.
             | Intractable problems or recurring issues in one industry
             | can frequently be unblocked by plucking mature solutions or
             | approaches from another, but so many people grow linearly
             | within a single industry/discipline that such cross-seeding
             | of concepts rarely actually have an opportunity to occur.
        
         | kkylin wrote:
         | Reminiscent of Dantzig's story:
         | https://en.wikipedia.org/wiki/George_Dantzig#Mathematical_st...
        
       | m3kw9 wrote:
       | " To make a knotted object in four-dimensional space, you need a
       | two-dimensional sphere, not a one-dimensional loop. ". You just
       | need to assume it's right.
        
         | saagarjha wrote:
         | You can't have a one-dimensional knot in the fourth dimension,
         | because it's trivial to pull it apart if you move part of it
         | into the fourth dimension.
        
       | generationP wrote:
       | Correction: Her MIT position (a Moore instructor, at least
       | according to her own website
       | https://sites.google.com/view/lpiccirillo/home ) is _not_ a
       | tenure-track job (see https://math.mit.edu/about/employment.php
       | ). It's still one of the best academic jobs a fresh PhD can get
       | these days (certainly more prestigious than a "mere" postdoc). I
       | don't think you can get a tenure-track job right out of your PhD,
       | even an MIT fake tenure-track job (they say it guarantees you
       | tenure, just not necessarily at MIT).
        
         | mehrdadn wrote:
         | > I don't think you can get a tenure-track job right out of
         | your PhD, even an MIT fake tenure-track job (they say it
         | guarantees you tenure, just not necessarily at MIT).
         | 
         | I know some (very bright) graduate students do get assistant
         | professor positions at top universities right out of their
         | PhDs; I _think_ those are tenure-track?
        
           | generationP wrote:
           | Who?
           | 
           | My guess is that these are "named postdocs" ("[some name]
           | Assistant Professor", e.g.
           | https://www.mathjobs.org/jobs/jobs/14065 or
           | https://www.mathjobs.org/jobs/jobs/15707 ). Despite their
           | names, they're limited to 3 years and only get renewed in
           | exceptional circumstances.
        
             | mehrdadn wrote:
             | I'm not going to name names here but I'm aware of at least
             | one person whose title is a "named" Assistant Professor and
             | one whose title is (from what I can tell online) just
             | "Assistant Professor".
        
       | smitty1e wrote:
       | Outstanding work.
       | 
       | Let us dub Lisa Piccirillo a "Space Age Bo's'n Mate".
       | 
       | https://en.wikipedia.org/wiki/Boatswain
        
       | wesammikhail wrote:
       | Too bad Conway didnt live long enough to see this.
        
         | ttymck wrote:
         | If I'm not mistaken, it says her findings were published in
         | Annals in February, and Conway passed in April.
        
         | gre wrote:
         | The paper is from 2018 so he might have seen it.
        
       | melvinroest wrote:
       | From a high level overview what she did feels mostly like a
       | hacker approach: finding a side channel [1]. I wonder to what
       | extent mathematicians think about side channels.
       | 
       | Instead of talking to the service/mathematical object (A)
       | directly, you talk to another service/mathematical object (B)
       | that leaks information about (A). Precisely, the information that
       | you want.
       | 
       | The way she leaked that information was through a property called
       | traceness that apparently was underappreciated by knot theorists
       | in terms of sliceness problems. Which makes sense, otherwise it
       | wouldn't be an information leak. Finding an info leak in itself,
       | no matter what discipline your in is already amazing.
       | 
       | As far as I understood the quantamagazine article, mathematical
       | object (B) still had to be constructed which only a person well-
       | versed in knot theory could do. So not only did she find an info
       | leak, she basically created something entirely new that few
       | people can do (yep, the hacker analogy breaks here, this part is
       | the "incredible builder" analogy).
       | 
       | This is so cool. Side channels are everywhere, even in math.
       | Apparently, for knots it's called traceness.
       | 
       | [1] Not sure if side channel is the right word, but I view it as:
       | something that leaks information about another thing. For
       | example, air vibrations leaking information on what instructions
       | the CPU is executing (I'm making this up, one would need very
       | fine-grained air vibration data to see if this would be a side
       | channel).
        
         | sdenton4 wrote:
         | My area was algebraic combinatorics, which is all about this
         | kind of thing. Combinatorics, representation theory, and
         | geometry share a bunch of objects related by some translations
         | from one field to another. So you make progress in one field
         | until you get stuck, then translate to another to make further
         | progress... And repeat.
        
         | empath75 wrote:
         | Dualities are what you're thinking about.
         | 
         | https://en.m.wikipedia.org/wiki/Duality_(mathematics)
        
         | terramex wrote:
         | You could argue that one of the most famous proofs of last 30
         | years - proof of Fermat's Last Theorem used such approach.
         | Andrew Wiles had proven that if this FLT was false, then
         | certain theorem about elliptical curves (unrelated at first
         | glance and from different area of mathematics) would have to be
         | violated, and mathematicians already knew it was true.
        
       | [deleted]
        
       | j7ake wrote:
       | What a great story. It's something we can all learn from.
        
       | contemporary343 wrote:
       | Even in the most technically demanding and theoretical of
       | disciplines (and in some sense, perhaps especially so) it is
       | creativity and an ability (instinct?) to see possibilities that
       | others don't that distinguish the best researchers. This is a
       | wonderful example of that.
        
         | [deleted]
        
         | melvinroest wrote:
         | I have immense respect for researchers who venture in these
         | type of disciplines. I don't think I would be able to do it. I
         | do have a bit of a daring question: isn't there a slightly more
         | fine-grained way to quantify that every nook and cranny of such
         | a problem has indeed be researched by researchers? I simply
         | assume that a rigorous research by the best minds of the world
         | has happened, but I never see any data on it, not even
         | anecdata.
         | 
         | I mean, I remember a post from Julia Evans, making a Ruby
         | profiler, where she was astonished on how few people were
         | actually working on it [1].
         | 
         | I suspect that in some cases, probably not this one, but in
         | similar theoretical fields, a similar thing might be occuring.
         | And if not, how do we test that? I'm probably not the only one
         | who's curious.
         | 
         | [1] I found a talk of her in which she emphasizes on it:
         | 
         | > So the three myths that I want to start out by talking about
         | are myth one-- to do something new and innovative you need to
         | be an expert-- myth two-- if it were possible and worthwhile,
         | someone would have done it already so you probably shouldn't
         | try-- and three-- if you want to do a new open source project,
         | you need to code a lot on the weekend and your evenings.
         | 
         | https://www.deconstructconf.com/2018/julia-evans-build-impos...
        
           | contemporary343 wrote:
           | An interesting thought. My understanding is that the library
           | science community has been investigating this for some time
           | in terms of the development of ontologies and libraries to
           | try to categorize research output. Here's a random paper I
           | found on the broader topic:
           | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3129146/
           | 
           | I suspect that this field is vastly under-studied and
           | investigated relative to what it ideally should be.
           | 
           | Generally speaking, it is easier in more theory-driven sub-
           | fields to probe new areas. And indeed it is often rewarded.
           | It's harder when $ is needed for experiments since that
           | becomes more grant process-driven (something which is
           | inherently more risk-averse).
           | 
           | My observation is that usually a few pioneering people push
           | out into a new topic area. Then, whether a community forms
           | around it and starts getting excited about it depends a lot
           | on timing, luck and also resources. Sometimes nothing happens
           | for decades until the stars align and people realize that
           | there's something there.
        
       | pmiller2 wrote:
       | Link to paper: https://arxiv.org/abs/1808.02923
       | 
       | I have not read the paper, but I have skimmed it briefly, and it
       | looks pretty exciting. This isn't a case of "here's a new
       | invariant, and, oh, BTW, it works to show the Conway knot isn't
       | slice." It's an actual new technique. And, at first glance, it
       | looks like a pretty simple technique. I didn't immediately see
       | anything here that wasn't just a neat combination of low
       | dimensional topology and basic knot theory techniques.
       | 
       | I'd be interested to see what this technique could do with knots
       | having more than 12 crossings.
        
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       (page generated 2020-05-19 23:00 UTC)