[HN Gopher] Math Overflow users resolve PhD thesis crisis ___________________________________________________________________ Math Overflow users resolve PhD thesis crisis Author : DarkContinent Score : 470 points Date : 2020-08-04 12:55 UTC (10 hours ago) (HTM) web link (mathoverflow.net) (TXT) w3m dump (mathoverflow.net) | fizixer wrote: | OP is incredibly fortunate. Or maybe mathoverflow is that | active/supportive. | | As a STEM grad student (not in math), I had more than a couple | such moments of crises, when I posted my questions on various | stackexchange websites. I got either useless replies, or no | replies. | thaumasiotes wrote: | I was contacted by someone in a PhD thesis crisis who wanted me | to provide speech samples they were apparently missing. The | thesis was due imminently. | | As far as I could tell, the analysis was already done -- but my | samples were needed for some other reason. I was kind of bemused | by the idea that the analysis would be invalid with nothing | behind it, but valid with unrelated data behind it. | lifeisstillgood wrote: | The walled garden sweet spot | | Stack overflow and it's cousin sites have many serendipities like | this - and I happily conjecture this happens more here than | facebook or twitter. | | I think the reason is that despite being a walled garden (ie | proprietary) it still has a promise to open up the content and | makes effort to moderate and grow the community - in other words | what they are really selling is not the SEO but the sweet spot | between "anyone posts anything" of an "ideal" internet where no | rentiers exist but no one can find anyone else, and the much more | corporate hand of Facebook. | | I am not sure reddit exists in this sweet spot either - mostly | because there is just sooo much reddit. | Dirlewanger wrote: | Both reddit/SO and say, classic forums, each have their own | method of content discovery (reddit/SO always prioritize new | items, forums push you to long-running threads), but both have | their blind spots. With reddit you can end up with a lot of | duplicates because a subreddit's dashboard decays stuff pretty | fast based on the frequency of posts. It makes long-running | discussion impossible. With forums you can have your long- | running discussions, but you sometimes have to wade through | page after page to find those specials nuggets of info. | munificent wrote: | I look at this as a fundamentally hard problem of information | design. You have a series of posts to present to a reader. | Which posts do you give primacy to? | | If your reader already knows most of the context and has read | the previous posts, then "re-posts" are bad, long-running | threads are good, and they just want to see the latest | updates. | | If your reader is coming to the material cold, a "re-post" | may be completely new to them, and posts that presume pages | and pages of existing context are completely impenetrable. | You want to lean towards fresh, short threads. | | The challenge for designing a forum then is balancing the | competing needs of those users. You can make some progress by | tracking on a per-user basis which comments they've already | seen. Reddit does that (maybe just for gold accounts?) where | new comments are blue. That makes it pretty easy to skim | through a comment thread and see just the new leaves. | | But there's still the question of how to sort the threads | themselves. It might be interesting if that sorting was also | user-specific. Maybe deprioritize threads that you've seen | but not interacted with, and prioritize "live" threads that | you've participated in and are still changing. | gowld wrote: | SO is a garden, not a walled garden. | neves wrote: | I always say that the wonder of the Internet is the | collaborative Wikipedia, not Facebook walled garden. Stack | Overflow network of sites is another of the great Internet | wonders. Non technical people can not grasp how fantastic they | are. Younger developers do not imagine a world without SO. | | As a private company, probably someday they will lost their | techno-utopian magic (as Google already lost). It will be a | very sad day. | Shog9 wrote: | A couple relevant bits of info about MathOverflow: | | - The site is operated by Stack Overflow/Exchange, but is | _owned_ by MathOverflow, Inc a non-profit corporation[0]. As | such, it retains the right to exist independently of the Stack | Overflow company - to my knowledge, it is the only public Stack | Exchange site for which this is true. | | - Like all public Stack Exchange sites, authors retain | ownership of their work, which is published under a CC-BY-SA | license. Regular archives are uploaded to Archive.org and can | be obtained there or via Bittorrent[1] | | In short, not a walled garden, and not Stack Overflow's garden. | | [0]: https://meta.mathoverflow.net/questions/969/who-owns- | mathove... | | [1]: https://archive.org/details/stackexchange | lifeisstillgood wrote: | Re: MathOverflow Inc - I had not only not heard of this, but | never even considered it was possible :-) | | Yes, I think I am wrong to use the term walled garden, but | it's hard to think of something else. | | In a "platonic ideal" of the internet everyone would have | their own internet connection, and a server and say post | their own interesting queries and somehow others would find | and answer them. | | Perhaps search was assumed to solve it all then. | | But the universe is much more "clumpy" than that so people | will gather around certain locations, in nature they are | natural oasis. | | Perhaps we should drop the walled garden idea - gardens, | walled or otherwise need tending and upkeep and that passed | the ability of one or two people to do in their spare time | somewhere around 1991 on usenet. | | Tending a garden is a costly affair. | | I think perhaps walled city might be a better term? It | implies the "never leaving" which is what facebook seems to | aspire to. | | perhaps a better analogy is "chargeable car parking". :-) | Shog9 wrote: | This is yet another one of those situations where the use | of a dying metaphor[0] hurts communication; you wall up a | garden to protect what is inside from the harsh conditions | outside: wind, cold, vermin... The implication is that the | people in the garden are delicate flowers who would be | destroyed by the conditions on The Greater Internet if they | were to be exposed. | | The antonym to the walled garden is the open garden or | field, with hardy plants able to withstand and even thrive | in the local atmosphere. They're still _cultivated_ - | weeded, fertilized - but there 's no need to create a | microclimate to just to accommodate them. | | In this context, Facebook does make some effort toward | walling off their gardens, but... As you note, Facebook's | primary goal isn't protecting it's _dominating_ - Facebook | is just as happy to own major portions of the 'Net in | pursuit of this goal, and more than a little reluctant to | provide any real protection beyond what is absolutely | necessary. | | Beyond that... We all garden. From little personal websites | and blogs, to big community gardens[1] like Wikipedia, | Reddit, Stack Overflow, and even Hacker News. We plant, we | harvest, we tend these plots, alone or together, but make | little effort to isolate them from the larger world - | indeed, we generally recognize that the strength of the Web | is based on its interconnections, its inherent ability to | draw together different sources of information. | | [0]: https://www.orwell.ru/library/essays/politics/english/ | e_poli... | | [1]: | https://meta.stackexchange.com/questions/349513/feedback- | for... | supernova87a wrote: | I have to say also that this type of crisis is not surprising | (unfortunately) for math, or similar highly theoretical, _loner_ | fields. I can guess that the student asking the question is not | being very open with his /her advisor, has worked and struggled | for long hours alone, thinking they have to solve it on their | own, and is not super communicative and checking in about | important aspects of the thesis. Because he/she thinks it has to | be a surprise "breakthrough" result -- a heavy obligation of the | field's expectations. | | No responsible advisor would let the work get to such a state, so | late in the game. Major fault of the advisor too, here. | jfkebwjsbx wrote: | Advisors are also very much at fault, not just students. | | The last year of my PhD I ended up being pretty much alone | because my advisor had changed research topics a year before | and therefore was not interested nor up to date, so any of her | inputs were not very useful. | | A couple friends of mine also struggled with their advisor | because he actively avoided communication for some reason. I | guess he had a personal or health issue. | | So even on good faith, advisors can end up making students life | quite stressful for one reason or another | generationP wrote: | As far as notational clusterfucks go, crossing numbers (along | with the three standard definitions of a ring) are one of the | best-known ones to still be biting people on a regular basis. | ("Positive" and "natural number" are sufficiently well-known that | people are careful.) But imagine how it felt to do group theory | back when "group" could mean any of "abstract group", "subgroup | of GL(n)", "finite group", "monoid", "semigroup" and combinations | thereof. | tgb wrote: | The simplest gotcha I know is: is f(x) = 1/x piece-wise | continuous?. This is calculus 1 level material and yet author's | disagree significantly on this point, sometimes without | specifying it! Some say yes, others would require f to have | finite left and right limits at every point. This mattered for | a point of my thesis and my advisor was very unhappy with me | calling these function piece-wise continuous. | generationP wrote: | I thought this was only an issue in K-12, as anyone in | research math considers the domain and the target to be part | of a function, and then the problem disappears: The function | R \ {0} -> R, x |-> 1/x is not just piecewise continuous but | continuous on-the-nose. The function R -> R, x |-> 1/x | doesn't exist. The function R |-> some completion of R, x |-> | 1/x is continuous or not depending on which completion you | choose (the one with two infinities or the projective line). | | But I do recall a similar confusion happening with "piecewise | linear" (the question is whether the pieces have to fit | together). | nicoburns wrote: | > I thought this was only an issue in K-12, as anyone in | research math considers the domain and the target to be | part of a function | | Anyone is research math does consider the domain and target | to be part of the function. Alas, that doesn't mean that | they'll actually write down which domain and target they | have in mind. | gowld wrote: | f doesn't even have either of a right or left limit at 0. | | f is maybe (piece-wise) continuous _over what pseudo-domain_? | R or R\\{0}? | | You could axiomitize that an infinite discontinuity is like | an unbouned function as x->infinity, but then how would you | avoid 1/x being regular continuous? | | I think you are claimokg that a set being incomplete "at the | end" is different from a set having a hole in the middle -- | that the question of continuity presumes _connected_ sets. | That 's not standard but might be an appropriate assumption | for the context of your paper. | | Anyway, arguing over terminology is boring unless it raises | conceptual issues. The point is to communicate, which has at | least 2 stakeholders. Clarify your terms and move on. | tgb wrote: | I think you missed the point of the example, which is that | people rarely clarify this because to the author their | definition seems obviously correct. I made it 90% through a | PhD without having considered that there could be more than | one possible meaning for "piece-wise continuous". | | The domain is R in this case. The less-restrictive | definition would be that f is piece-wise continuous if | there are a discrete set of points .. < x_0 < x_1 < ... | with f continuous on each interval (x_i, x_{i+1}). The | alternative definition is that, plus requiring that the | restriction of f to those intervals have limits at the | endpoint. For piecewise smooth function, there's an even | larger variety of possible meanings, yet it's often stated | without clarification. | thaumasiotes wrote: | > The less-restrictive definition would be that f is | piece-wise continuous if there are a discrete set of | points .. < x_0 < x_1 < ... with f continuous on each | interval (x_i, x_{i+1}). The alternative definition is | that, plus requiring that the restriction of f to those | intervals have limits at the endpoint. | | This sounds kind of surreal; putting them in shorter | terms, we have two rival definitions for "piecewise | continuous": | | 1. A function f is piecewise continuous if there exist | one or more intervals over which f is continuous. | | 2. A function f is piecewise continuous if there exist | one or more intervals over which f is (1) continuous, and | (2) bounded. | | I agree that it sounds obvious which of those is more | appropriate as a definition of "piecewise continuous"... | | (It also worries me that the definition you give requires | the intervals to be adjacent, but doesn't require that | more than one interval exist. A function that is | continuous over (-2, -1) and also over (1, 2), but not | anywhere else, would meet this definition, but you | wouldn't be able to include both of those intervals of | continuity in the set of endpoints. | | I would prefer to either have two sets of endpoints, such | that we end up saying f is continuous over (x_i, y_i), | (x_{i+1}, y_{i+1}), etc. (if we want to allow for | intervals of discontinuity), or to say that the intervals | (-inf, x_0) and (x_n, +inf) also count (if we don't). | | However, if we take that second approach, and we go with | the definition of piecewise continuity that requires the | function be bounded over every interval, we've just | defined functions like f(x) = x as being not piecewise | continuous despite the fact that they are continuous.) | Ericson2314 wrote: | The idea is that what 1/x is is intuitively simple enough, | so we should have some standard terminology for it. | | And saying left and right limits is -infinity or +infinity | really also isn't that weird. I'm pretty sure other metric | spaces can be likewise extended and end up with similar | algebraic laws as the "extended real numbers". Again this | isn't very profound, but is good for education and | efficient communication, and so should be perused. | | Finally, it's interesting that measure spaces with infinite | measure is already a thing that people. I would like to see | more connections with metric and measure spaces; e.g. we | can have an n-point metric which is defined using the | measure of the (n-1)-simplex. Just as regular metric spaces | have a "triangle inequality", 3-point metric spaces should | have a "tetrahedron inequality", and n-point metric spaces | should have a "(n-1)-simplex inequality". Again, this is | not profound, but good for communication, and connections | between definitions help one compress everything for better | mental storage. | gus_massa wrote: | I teach math in the first year of the university and it's not | a good moment to discuss about the subtle details of topology | and definitions. So every time someone ask me that, I reply | "It is not continuous for _all_ the real numbers " | OskarS wrote: | The way I was taught was that back in the olden days, "group" | always referred to groups of permutations (and the operation | was always composition), and it was Cayley that introduced the | much more general and abstract notion of groups that we use | now. He could do that because it's relatively trivial to prove | that the the two definitions are basically the same: every | group is isomorphic to some group of permutations according to | Cayley's theorem: | https://en.wikipedia.org/wiki/Cayley%27s_theorem | generationP wrote: | Sure you can embed any group in a permutation group, but that | doesn't mean the two notions behave identically in all | respects. For example, two groups being isomorphic is not the | same as two permutation groups being isomorphic, as the | latter come with their embeddings. | wenc wrote: | This reminds me of my Ph.D. crisis. (which I'm sure many former | grad students can relate to) | | I was in my 6th year. All my friends had graduated, and my | stipend had run out. I was 2 weeks away from submission and | discovered that one of my assumptions was wrong, which | potentially distorted/invalidated all my studies -- to fix these | studies would have potentially delayed submission for months. It | was a very subtle assumption violation (and it wasn't even that | wrong) and my committee probably wouldn't even have noticed. I | was tempted to sweep it under the carpet and not let it keep me | from graduating. | | But I knew it was wrong. I felt that if I sacrificed my integrity | then, the moral failure would mark me for life. No one would know | -- but I would know. So I decided to fix the issue, re-do the | studies and live with the reality that I would have to delay my | defense. | | Turns out when you're desperate -- and many grad students can | attest to this -- a resourcefulness that you never thought you | had kicks in ("where were you during all my years of grad | school?"). I don't remember how, but I somehow managed to wrangle | new studies out in 3 days (which would have previously taken me | months). I made the deadline in the end. | | The lesson I learned was that committing to doing the right thing | has its costs, but in some cases it also forces one to explore | attacks never previously considered. Asking on MathOverflow is | one such attack. | sadfev wrote: | Your comment is a lifeline to me in this difficult time. | | Why are we not resourceful in normal time? | Enginerrrd wrote: | I wish I knew the answer to this. When everything is totally | screwed up and on fire and I need to get something done by | 5:00 today that would normally take a week and a half, by | God, it becomes apparent every millimeter of fat that can be | trimmed and I can usually scrape together what's needed by | then. Then the deadline is over and I get a similar project | the next day and it's back to taking 5 days to finish. | | There are real quality differences between the two scenarios, | but they aren't nearly as bad as what you'd think they are. | The reality is that I can just work a lot more efficiently | when stressed. If I could do that all the time I'd be able to | work 3 hours a day and remain as productive. | mordymoop wrote: | The "point" of gradual school should be taking long walks | with friends from completely different departments, talking | about abstract ideas that aren't related to your work at all. | Maybe later in the shower you realize some subtle connection | to your work that gives you an idea for an innovation, but | maybe not. The point of graduate school is play. The switch | from "play" to "product" is difficult but necessary. Both | phases are important to the budding PhD. You need to | demonstrate the ability to think creatively AND the ability | to process that creativity into a deliverable. That's the | value of a PhD. If you're interested in a focused grind to a | specified finish line, skip graduate school. | YeGoblynQueenne wrote: | Because in normal time we spend most of our time reading HN | rather than working on our urgent stuff. | infogulch wrote: | Whelp that's my signal to get back to work. | dleslie wrote: | It's not typically sustainable to operate at such high levels | of stress, but the stress brings with it a myriad of hormones | and behavioural adaptions that, for some people, aid in | sustaining focus and effort. | lotsofpulp wrote: | It's selection bias. There are probably far more instances | where rushing through causes problems than there are where | rushing through doesn't. | gandalf013 wrote: | Hobbes: Do you have an idea for your project yet? | | Calvin: No, I'm waiting for inspiration. You can't turn on | creativity like a faucet. You have to be in the right mood. | | Hobbes: What mood is that? | | Calvin: Last-minute panic. | [deleted] | foepys wrote: | > Turns out when you're desperate -- and many grad students can | attest to this -- a resourcefulness that you never thought | you'd had kicks in | | This is getting millions of students through high school, | college, and university every year. | | Everybody has at least one thing they pushed back for way too | long and then developed almost super-human-like abilities to do | it. Doesn't guarantee a good grade, though. | pvarangot wrote: | In my humble experience this force of human will also gets | early stage startups a second chance or saves them from | sudden death regularly. | mjklin wrote: | The book "Godel, Escher, Bach" was printed with a special | process only available at one printer far away from where | Hofstadter was living, and was extremely time consuming. At the | last minute the whole thing had to be redone, so he had to get | on a plane, print a few pages, then fly back to his job. This | took several months. (He talks about it in the 20th anniversary | edition.) | dmch-1 wrote: | My laptop broke down just hours before I had to submit the | thesis. It was the day of the deadline. I did have printed | copies of the thesis (I had to submit printed copies), however | I discovered bad typos on the front page. But, my laptop was | down with the only digital version in it. In the end, I | corrected the typos using a photocopier. I overlayed the typos | with corrections on cut out pieces of paper, and photocopied. | It was quite a struggle, but I made it! | supernova87a wrote: | There's another (slightly kinder) version of this: | | When people go to grad school, then during their studentship | get married and have a kid -- suddenly their productivity goes | up dramatically and output per time increases by many factors. | What happened? | | It turns out when you have self-motivating reasons to get out | (and a target on your head from your spouse to earn some money | for godssake), you find ways to focus on what's important and | drop the rest. | | No more idling away for hours on silly ideas that don't get you | closer to handing in your thesis. No more trying random | libraries that get your code to run 2% faster. No more goofing | around after 6pm with other students just because you have the | time -- you have to get home and be a breadwinner for your | family. You have to get shit done. | | You start to ask, "even if I don't know exactly what the thesis | will say, how should it be organized and what _kinds_ of | conclusions will make up the writing? And what experiments do I | need to fill in those charts /paragraphs, and _no more_? " | What's the minimum I need to do to get out of here? Not, "What | amazing interesting thing could I explore?" | | Limits and constraints sometimes free the mind dramatically. | The side effect is maybe you don't get to explore ideas that go | nowhere, but that's a discussion about the purpose of the PhD | and for another topic I guess. | | (And sometimes, if you think, well I don't have a kid, so | what's the rush? Well, someday you might have a spouse, a kid, | and every day of time you left in grad school is a day for your | future self -- and family -- and $$ -- left behind in time. | Work to free your future self... now, while you have the time.) | supernova87a wrote: | I might offer a corollary as an practice to adopt (in the | absence of the above possibility) -- learn to enable your | research to have visible incremental gains on a known path | every day, rather than hoping (hoping!) for some amazing | breakthrough at the end. | | Amazing breakthroughs have high risk, and make it highly | likely you'll have a crisis when it doesn't happen. | | And what I mean is that, even if you don't know what the | answer is going to be at the end of your research, you must | think about, or have an idea about, the _format_ of what that | amazing answer is going to be. Write the outline of your | thesis and "ghost out" what the major charts will be. Write | the intro sentences of each chapter -- what are they? (and I | don't just mean the boring review of the field part, but your | findings part) | | You should know what major finding, plot, or table your | research is going to output. What are the columns and rows of | that table, or axes of that plot? How many data points are | required? How many of them can already be guessed? Where is | the surprise going to be? What is the conclusion going to be? | | For most graduate research, the finding is not an amazing | field-changing big bang. Few grad students are that | fortunate. Or at least most of the bulk of the work will be | of that sort. You should be able to predict what the answer | is going to look like from past work, and the error bars. | | Draw out the answer you're aiming for, now. If you can't even | articuate what the answer will _look like_ , you may be in | for a bad time, so work on fixing that. It will also push you | and your advisor to be specific about what the output of your | thesis will be. | | Your future self will thank you. | newen wrote: | One of my professor's recommendation was to write the | actual paper that you want to write, introduction, related | works, methods, discussion, conclusion, leaving the | figures, tables, etc. blank, before you actually start | doing the experiments. | mkl wrote: | This reminds me of Simon Peyton-Jones's (of Haskell fame) | seminars on How to Write a Great Research Paper: | https://www.microsoft.com/en-us/research/academic- | program/wr... | | There are multiple slightly different versions of the | seminar (another is linked below that one), but | unfortunately they all came out after I'd finished my | PhD, and I didn't hear that advice from anyone else. | | The process I arrived at after losing time on failed | projects was basically "fail fast": find the simplest | quickest way to demonstrate that your idea _won 't_ work, | and do that. Then find the next simplest, and so on, | until either it works or you've proven it doesn't and | moved on. | supernova87a wrote: | Many advisors don't push their students to do this, and | they should. Or they haven't had enough practice to know | to do this. Or they're not taking their responsibility | seriously enough. | | An effective PhD advisor/thesis isn't wandering the woods | to find something. It's a guided coaching exercise, with | an outcome in mind. If your advisor doesn't know this, | maybe time to find a new advisor... | Twisol wrote: | > An effective PhD advisor/thesis isn't wandering the | woods to find something. It's a guided coaching exercise, | with an outcome in mind. If your advisor doesn't know | this, maybe time to find a new advisor... | | You don't know me, but I really needed to hear this. I | left grad school essentially because of a dearth of | coaching. Thank you for framing this so succinctly. | mensetmanusman wrote: | This is amazing advice I hadn't heard before, it rings | very true. | | I remember after my first paper was finished and | submitted, and wow, it seemed easy to bang out papers | after that, all you needed was four to five figures :) | kiba wrote: | _For most graduate research, the finding is not an amazing | field-changing big bang. Few grad students are that | fortunate. You should be able to predict what the answer is | going to look like from past work, and the error bars._ | | Does it ever works that way for field changing big bang | ideas? Every human achievement was built upon the back of | previous achievement and works, either by you or someone | else. | thomasahle wrote: | > You should be able to predict what the answer is going to | look like from past work, and the error bars. | | If you basically know the answer in advance, chances are | you are not doing very interesting research. | | The worst work I have done has been of this sort. The best | has had me completely change my view of (mathematical) | reality multiple times during the process. | supernova87a wrote: | Well, I'm of course emphasizing empirical fields. Maybe | you're in one of those heavily theoretical fields. | thomasahle wrote: | In emperical fields as well I would assume the purpose of | doing experiments is that you don't already know what the | result will be. I accept that this may be a idealised or | naive... | supernova87a wrote: | I'm not talking about the exact result, right? Just that | someone engaging in research should know what the format | of the plot/table/output should look like, how much work | is needed to populate that table, and what kind of | conclusions will come out of it. | | If you (the general "you") are in industry breakthrough | territory, you're an advanced student and my advice isn't | for you. Otherwise, I think it's a good practice. | thomasahle wrote: | > what kind of conclusions will come out of it. | | Fair. I think considering what possible conclusions could | come is certainly important. I worried about your | original post suggesting actually writing the conclusion | in advance. | JamesBarney wrote: | Hmm this is different than my experience when my co workers | had kids. Usually their productivity dropped due to being | sleep deprived and not having the time on nights and weekends | to come up to speed on any new technology. | | Not that I minded, just saying that time constraints and | sleep deprivation seemed to have the effect you'd except from | them. | alfonsodev wrote: | productivity at work is harder to measure than academic | achievements, also different setup and motivations in play. | iateanapple wrote: | > Usually their productivity dropped due to being sleep | deprived | | High levels of sleep deprivation is only common for the | first few months. | | > not having the time on nights and weekends to come up to | speed on any new technology. | | This tends to be a problem on teams that don't properly | evaluate costs of new technology and so churn like crazy | for very minor productivity increases. | keithnz wrote: | it wasn't about coworkers.... when people are working they | often get paid the same no matter what their productivity | is, so the motivations are different | hprotagonist wrote: | grad students and coworkers have very different priorities. | bigfudge wrote: | This happened to me. I typed the last paragraph of my thesis | shortly after my wife went into in labour. It was very | satisfying to hear it printing while I was filling the | birthing pool in our living room! | QuercusMax wrote: | Before I got engaged to my wife(who was a year ahead of me in | college) I had plans to do some kind of individualized honors | project across 2 or 3 different majors (physics / math / CS). | | I very quickly found myself reprioritizing how quickly I | could graduate and find a job (since my wife's field didn't | have many lucrative career prospects). | mensetmanusman wrote: | This was me, had a 1 year old at my thesis defense on Mass | Ave :D | cacois wrote: | This rings so true to me. I got engaged during the last 6 | months of my PhD student tenure, and lo and behold, I | defended my thesis in the same month we got married. In the | same vein as above, the added perspective and fire under me | resulted in a number of novel solutions to problems that | probably would have been major issues in the past, including | a full change in direction of my research conclusions after | realizing a substantial issue in the practical application of | the technology. | | I credit my now wife with the (passive) motivation to shave | at least 6-12 months off my time in grad school. | chrisseaton wrote: | Lol my wife had a baby while I was doing my PhD... was a | less-than-ideal way to structure your life I'll admit. Do not | recommend. | ColanR wrote: | > What's the minimum I need to do to get out of here? Not, | "What amazing interesting thing could I explore?" | | I totally get it, but it makes me sad. That line, right | there, probably explains why it's so few people who actually | get to make the big discoveries. | no_identd wrote: | >"the faculty will not accept asymptotics" | | the hell does that mean? | impendia wrote: | (Math professor here). | | Ambiguous and poorly explained. (Note the question immediately | afterwards asking for clarification.) But probably something | along the general lines of "My advisor said that, if my main | theorem is an asymptotic estimate instead of an exact formula, | then this would not be judged to be novel/strong enough to earn | a Ph.D." | mywittyname wrote: | If you don't mind, could you explain the practical difference | or the reasoning behind such a requirement? Are there | situations where boundaries appear to be asymptotic but the | exact solution shows this not to be the case? | boyobo wrote: | I mean, maybe they need to exponentiate the bound or | something. e.g. 2^(4n) is much much much worse than 2^n. | | The sentence did strike me a little wierd though. | rrobukef wrote: | I re-implemented a quasi-polynomial algorithm. | Experimentally, it shows exponential behaviour. Back-of- | the-envelope calculation shows this behaviour can continue | until the input size is >>10^21 before the asymptotic bound | asserts itself. (For comparison, input size 30 is | unfeasible) | Ragib_Zaman wrote: | Which algorithm? | truthwhisperer wrote: | (try to be funny) depends if you are on the university | where 2+2 can also be 5 depending on your feelings | impendia wrote: | Once again, I don't understand the Math Overflow poster's | exact situation. | | But roughly speaking, imagine you have two functions f(t) | and g(t), which are described in completely different ways, | and you want to prove that f(t) = g(t). If you try and | fail, then you might instead aim for a proof that the | difference between f and g is bounded, or that f(t) = | O(g(t)) and vice versa, or that the limit of the ratio | between f and g is 1, or something along these lines. | | In many cases, such partial results are also of interest. | In general, partial successes in math are considered to be | successes. | | But in some cases, partial results aren't really considered | all that interesting -- or perhaps are known already or can | be obtained very easily. | ReedJessen wrote: | This kind of "social media" gives me faith in the ability of | humanity to survive and thrive in the future. | oconnor663 wrote: | A neat comment on the accepted answer: | | > From OP's point of view this could be viewed as glass half-full | rather than glass half-empty. Their dissertation results hold | unequivocally on the sphere and might hold on the torus, though | it is an open problem if they do. It is certainly legitimate to | study what follows from a given conjecture being true. It could | even be spun as a feature rather than a bug of the dissertation. | If the results in fact fail on the torus then you know that the | conjecture must be false. Potentially, it could open up a | fruitful avenue of attack. | | Kind of reminds me of Terence Tao's post on what solving big | problems looks like: https://terrytao.wordpress.com/career- | advice/be-sceptical-of... | finolex1 wrote: | As an aside, looks like one of the comments in the Math | Overflow link above was made by Terence Tao himself | oconnor663 wrote: | Oh neat! | thechao wrote: | When Terence Tao writes stuff like this, I'm always very happy | that I got to experience the Moore-method for learning math (at | UT Austin). A group of us would be dumped into a class with a | common topic and we'd just have to _prove_ things (topology, | algebra, analysis) ... on the blackboard, in front of everyone. | The best work we did was when something started going wrong and | then we 'd all start arguing about the proof, building count- | conjectures on the fly and riffing on the math. The worst work | was when someone went and found a proof _ahead of time_ and | just showed the answer. There 's so much to learning where the | sharp bits of math are; proofs are the razor-thin path through | the briar patch. | | It was only later that I found out that history, the study of | art & literature, and philosophy can all teach you the same | thing. The important part is that you're interested in the | topic. | nicoburns wrote: | > > There's so much to learning where the sharp bits of math | are; proofs are the razor-thin path through the briar patch. | | As a student representative for my undergraduate mathematics | course, I got really pissed off at lecturers for exactly this | reason: they'd write out a perfect correct proof on the | whiteboard, but wouldn't explain where it had come from or | how people had arrived at the solution. We were left to | figure that out on our own. | | They then complained that students were rote-learning for | exams, rather than coming to a full understanding of the | material. I'm not sure what they were expecting, given that | that's exactly how they were teaching it. | nwallin wrote: | My discrete mathematics professor was like that. He would | regurgitate a proof onto the whiteboard. Then he'd do it a | few more times with proofs of other things. | | He has an identical twin brother, who is also a math | professor at the same college. The regular professor was | out for a day, and his brother came in to teach the class. | His teaching style was completely different. "Ok, we need | to prove X. Where should we start?" and would sit on the | table and look at us with an inquisitive look on his face. | Then learning happened. | | Everyone's mind was blown. Most people didn't realize it | was a different person. Then on Thursday it was back to | same-old same-old. | | I still don't know shit about discrete math. | hackermailman wrote: | This is what Putnam seminars are like, the whole class goes | through problems together. A few of them are on Youtube, | maybe more will show up as everything is remote now. | truantbuick wrote: | > There's so much to learning where the sharp bits of math | are; proofs are the razor-thin path through the briar patch. | | This is an excellent metaphor using beautiful language. Did | you just coin this yourself or is it pre-existing? | thechao wrote: | I guess this is mine? I would hesitate to believe I made it | up, but I don't remember it from anywhere. If you don't | feel comfortable with that, then credit it to Michael | Starbird, who was my first Moore-method professor 20-odd | years ago. | mslm wrote: | Just felt the same way about the portion after the | semicolon; it's quite catchy as well! Please give a | reference or else if I use this later I'll have to say it | came from "some guy on hackernews". | AnimalMuppet wrote: | Cite it as "thechao on HN", not just as "some guy". | (Unless thechao gives you something more specific.) | theossuary wrote: | It reminds me of this math overflow answer: | https://mathoverflow.net/a/338620 | | I suspect the reason OP's thesis worked out okay is because his | intuition wrt the problem is correct, even if his formulation | was a bit off. Very cool, sounds like a good mathematician to | me | jb775 wrote: | Wisdom of the crowd in action. | | I feel like this wisdom isn't tapped into enough. We're often | burdened with individual tasks and challenges while utilizing | crowd knowledge is looked down upon or seen as an inferior | solution finding mechanism. e.g. Imagine if companies worked | together to figure out self-driving cars rather than compete? | leokennis wrote: | Low quality comment, but this once again confirms what I already | knew: I suck at math. | truthwhisperer wrote: | Maybe I don't understand but he should have been now in the | position to have already a few accepted publications. I'm mean | this seems strange to me a few weeks before due date or is his | supervisor on covid break? Don't get this honestly. Or is this a | paid phd? ___________________________________________________________________ (page generated 2020-08-04 23:00 UTC)