scrape_r_rational/data/cache/3dml73.md

[D] Friday Off-Topic Thread

Post:

Welcome to the Friday Off-Topic Thread! Is there something that you want to talk about with /r/rational, but which isn't rational fiction, or doesn't otherwise belong as a top-level post? This is the place to post it. The idea is that while reddit is a large place, with lots of special little niches, sometimes you just want to talk with a certain group of people about certain sorts of things that aren't related to why you're all here. It's totally understandable that you might want to talk about Japanese game shows with /r/rational instead of going over to /r/japanesegameshows, but it's hopefully also understandable that this isn't really the place for that sort of thing.

So do you want to talk about how your life has been going? Non-rational and/or non-fictional stuff you've been reading? The recent album from your favourite German pop singer? The politics of Southern India? The sexual preferences of the chairman of the Ukrainian soccer league? Different ways to plot meteorological data? The cost of living in Portugal? Corner cases for siteswap notation? All these things and more could possibly be found in the comments below!

Comments:

• u/Anakiri:

  So I was thinking about how to punch a clean tunnel all the way through a neutron star, and the obvious solution is to use a really fast black hole. Any matter that goes inside the event horizon doesn't come back out, and if it's going more than 0.99c, I think that it won't have time for its gravity to greatly influence the surrounding material, ergo: Smooth perfect tunnel with minimal collateral damage.
  
  (Which immediately collapses, but whatever.)
  
  The problems are, I don't know how to account for extremely high jerk when calculating effects. And, very large objects moving very fast produce gravity waves, and I have no intuition for wave mechanics at all. I know that wavefronts can build by constructive interference, which might make nasty tidal effects further out than I want. I just don't know. I'm also not entirely clear on the effects of relativistic mass on a black hole's Schwarzschild radius, but kugelblitzes (black holes formed from energy density of light) suggest that the radius comes from relativistic mass, which includes kinetic energy.
  
  So my question is this: If a 1 * 10^(26) kg rest mass black hole moving at 0.99c went straight down through a skyscraper without directly hitting any supports, what would happen? I think that it would carve a bottomless pit two meters across, but I don't know if the building would be left standing, or how far away it would be safe to stand when a hole suddenly appears with a thunderclap for no obvious reason.
  
  Pretending gravity is instantaneous, you would only experience more than 150 Gs of acceleration as long as the black hole is within 6,000 km of you, and it would enter and leave that range in 1/25 of a second, which seems within human mechanical shock tolerance, I think. Especially since the force is applied smoothly over the entire body, rather than delivered through discrete external points of contact. But the *peak* acceleration could be a few quadrillion Gs, which may limit survivability. Now, gravity isn't actually instantaneous, so the black hole is almost keeping pace with its own gravity, and you're not going to fall up towards it for most of its approach. Intuitively, its upward and downward accelerations should cancel in the end. so you might get hit with a huge upward hammer blow when it gets to you, then get pulled downward more softly over a longer time.
  
  It seems like it *should* be possible for it to go fast enough that its gravity just doesn't have time to destroy you, even if it is momentarily putting everyone on the planet in a car crash. At worst, I'm pretty sure it won't destroy the Earth probably. If it doesn't work, is there any way to fix it?
  

  • u/None:

    I've got no idea the answer to your question, but I'm upvoting you in the hopes that you find one, and replying to let you know that this comment really made me laugh, because oh /r/rational what are you.
    
    >the obvious solution is to use a really fast black hole
    
    If you ever hear someone say that, I advise that everyone turn and run in the opposite direction *really fast*
    

    • u/None:

      [THIS HAS NEVER BEEN MORE APPROPRIATE.](https://33.media.tumblr.com/c390fb3d7e9d70e38e5266f11183b201/tumblr_mz5p23G92K1s5f9ado1_500.gif)
      

  • u/ulyssessword:

    I tried doing the math, and I *think* I got something that works.  What I got is that the total impulse on an object X distance away from the path is ~1.6x as much as if the black hole had been sitting at its nearest point for as long as it takes to travel X distance.
    
    For example, if something was 1km away from the path, and the black hole is travelling at 1 * 10^5 km/s, then you could model the effect on it as the same as it sitting at the nearest point for 1.6 * 10^-5 seconds.
    
    [Here](https://docs.google.com/spreadsheets/d/1EgSuhJnARILsfba6ceqUmlDpKyoyRAlJomZbBDn0_UY/edit?usp=sharing) is the spreadsheet I used to calculate it.  The first page is a proof of concept, the second page is the same thing, but better.  I couldn't figure out how to do the actual calculus, so it's 2000 discrete points instead.
    

• u/Escapement:

  I've been playing lots of three of Zachtronic's puzzle games recently, and they're really fun and excellent.  They establish rules, then force you to exploit the rules to solve problems efficiently. They are very good at teaching ideas about logic and planning and optimization and so forth.
  
  The three games I've been playing are:
  
  Spacechem - based *extremely* loosely on chemistry (more of a chemistry artistic motif then any real chemistry). Involves bonding and debonding atoms, fusing and fissioning atoms, to make inputs into desired outputs, using a system of relays, detectors, grab-and-drop plans, etc. Solution usually involves making a certain number of desired outputs from inputs.
  
  Infinifactory - Move blocks around to make and modify things in 3D, creating assembly lines of conveyors, pushers, welders, detectors, lasers, and all sorts of other tools. Set up an assembly line and watch it go.
  
  TIS 100 - The assembly language programming puzzle game you never knew you wanted. Using a grid of extremely simple computers with an accumulator and a ram storage for a single integer, write code to do things like detect edges, multiply, find min and max of sequences, etc. 
  
  They all provide heaps of fun just trying to solve the puzzles at all, but then after that you can try to make your solution better - either faster, or using less resources and building blocks. They teach a lot of ideas about planning, programming, logic, and so forth, in the course of the action of the game. 
  
  Infinifactory even has a hotkey to make looping gifs like [this one I made of one of my solutions](http://i.imgur.com/UoEk9R4.gifv)
  

• u/ToaKraka:

  Are there any scenes from *Time Braid* that particularly stood out to you?
  
  The one that has stuck in my mind the most is [this spoiler](#s ""I am Sakura's aspect of light... and your eyes have no power over me", from Sakura's fight against Sasuke in the Forest of Death--and that Cutting Water Dance!").
  

  • u/eaglejarl:

    The literally dehumanizing torture, brainwashing, and probably rape.
    

    • u/None:

      Yeah, that part is why I dropped it the first time. What was even the author thinking?
      

      • u/Jace_MacLeod:

        I personally thought it was a realistic portrayal, given a sufficiently sadistic Sasuke. Don't get me wrong - it was difficult to read - but isn't that a testament to the effectiveness of the writing? Torture's not supposed to be comfortable.
        

        • u/None:

          I don't see the point of making Sasuke sadistic and torturing her if she's just going to be fine a few chapters later with no real lasting effects. I never read it all so it might become relevant like 200k words later, but I just thought it was pointless, edgy, and pointlessly edgy.
          

          • u/Jace_MacLeod:

            It does become relevant later on. Sasuke's ability to brainwash people is what ultimately makes him such a dangerous villain. Probably a very major case YMMV; *Time Braid* is \*notoriously\* polarizing.
            

          • u/Solonarv:

            Oh, you're talking about chapters 3 and 4? Something similar is a pretty decently-sized chunk of the plot starting Ch. 22.
            

    • u/ToaKraka:

      [Spoiler](#s "Sasuke's Tsukuyomi torture sessions") were impressive, true--I can vividly recall the parts where [spoiler](#s "the strands of Sakura's hair turn into maggots and burrow into her body") and [spoiler](#s "Sakura's bones are extracted while she's conscious").
      

      • u/eaglejarl:

        I'm talking about the part where [Sakura](#s " is conditioned to the point where she will punish herself over and over in order to become what her torturer wants her to be.")
        

  • u/blazinghand:

    Probably the underage sex and rape. It, uh, turned me off from reading the rest of it.
    

• u/jgf1123:

  What is the rational thing for the eurozone, IMF, and Greece to do at this point?
  
  - Do the austerity measures specified by the recent deals have a chance of getting the Greek economy back on its feet and producing a surplus so that it can (eventually) pay back the debt?  (Call this forward-looking.)  Or are other nations just trying to 'punish' Greece for its past policy decisions?  (Call this backward-looking.)
  
  - If both are not possible, is it more important to keep Greece in the eurozone or to recover the lender's money?
  

  • u/None:

    Grexit has been the best move for a long time, and a large haircut or default.  The current policies *only make rational sense* as punishments, and as making an example of Greece for the other Southern European nations.  The Euro has broken European trade balances, but the North doesn't want to acknowledge that because it works to their benefit (and because the Germans believe running a trade surplus to be a matter of national virtue, and damn the accounting math that says their surplus *must* be someone else's deficit).
    

  • u/Jace_MacLeod:

    On the Greek side, I'd have executed a Grexit a long time ago. There's no advantage to staying in a monetary union that prevents a natural devaluation of currency (important for recovery in a bad economy), while simultaneously enforcing an insurmountable but undefaultable debt with little relief and punishing austerity. On the European side, I'd encourage Greece to stay in the union while offering considerable debt relief and minimal austerity. (Or just let Greece leave, if I didn't particularly care about it.)
    
    The problem is none of these parties are anything resembling rational actors. It's kind of impressive, actually. They're failing in ways that perfectly selfish agents wouldn't even *consider*, since perfectly selfish agents are at least rational enough not to act directly against their own self-interest. Greece in particular has been charting new ground in politco-economic failure. From [Vox:](http://www.vox.com/2015/7/13/8949925/greece-syriza)
    >Greece had two awful choices: Stay in the eurozone and be crushed by fiscal and monetary polices set by the Germans, or leave the eurozone and be crushed by a financial crisis. [Syriza] managed, horribly, to combine both of the original two options into one political-economic disaster…
    >
    >As O'Brien writes, “Syriza’s strategy, insofar as there was one, couldn’t have been much more of a failure.” If anything, that’s too kind. Syriza’s strategy, insofar as there was one, uncovered a method of failing that was much more complete and all-encompassing than anyone had thought possible at the start of the process.
    
    At this point, the only improvements I see for the short-term are a sudden change of heart by the Germans, or a Greek election putting a new party in power. Until then, it will probably be ongoing disaster as usual.
    

  • u/Escapement:

    I think austerity is unlikely to benefit Greece's economy long-term, and indeed will deepen their recession. I think it's in Greece's best long-term interests to exit the euro, and it would have been even better for them had they done that earlier. Short term it would hurt them, and probably any politician of theirs who made that decision would be effectively ending their career, but they would stabilize eventually and get something approaching a stable economy. I think it's beneficial to the others on the Euro if Greece stays in. I don't know if the harm done to Greeks by it's staying is outweighed by the benefits to the others, such that from a utilitarian perspective I should urge Greece to stay in -  I am not an economist or domain expert in these matters.
    

  • u/ArgentStonecutter:

    \#grexit
    

  • u/RMcD94:

    As a voice of disagreement, Greece leaving the Euro will probably not do any good for their economy. Default and staying in the Euro is much better than creating a drachma due to their [pretty large trade deficit](http://www.tradingeconomics.com/greece/balance-of-trade), if we're especially nice and suggest that the Drachma will devalue to say only 25% (rather than the 10% figure thrown around) imports will suddenly cost 16 billion Euros rather than the 4 billion they are paying now, and their exports will be worth 500 million. 
    
    Obviously they are hoping that they will be extremely competitive and somehow either avoid that much devaluation (unlikely) or pay for it with more debt (who is going to lend exactly to a government not backed by Europe? They don't have a primary surplus big enough to cover the trade deficit). 
    
    The best thing was in 2008/9 when it was clear what the crash was Europe bosses should've gotten around the table, decided which countries were going to default, what they were going to default on, and how much, then announced bond buying for countries to stop contagion and gotten on with it. Unfortunately the dragging out of this process has benefited no one.
    
    They can't really default any more so it's probably just going to be Europe financing their debts while they struggle to get back on their feet in austerity.
    

• u/None:

  [deleted]
  

  • u/Jace_MacLeod:

    For me it's always had the opposite effect. Actually, I'd say it's probably the closest thing I've ever had as a committed atheist to a religious experience. To glimpse, if even a little, at the immense complexity and scope of the universe; to marvel at the underlying physical laws from which we emerge like ripples in a pond - it's not *exactly* awe-inspiring, but it does generate an emotion very much like it.
    
    Now, from a certain perspective the relative tininess of human affairs might deprive it of meaning. After all, if we live in a universe which doesn't care for our existence, does anything really matter? Poppycock! True, *most* of the universe doesn't care for our existence, being a non-entity incapable of thought. But we're part of the universe *too!* And we clearly care. We have morality, even if it can only be applied to ourselves. We give each other purpose, in as much it's possible to have one. Indeed, the very concept of "purpose" is itself a human social construct! To quote HPMOR - there *is* light in the world, and it is *us!*
    

    • u/Sagebrysh:

      So much this. This is basically how I see it. Sure we're small, but we're smart, and getting smarter all the time. We still might be able to really *win* at reality, by whatever abstract measure of top level win conditions humanity might have. There's an awful lot of universe to explore and stick flags on.
      

    • u/boomfarmer:

      > Actually, I'd say it's probably the closest thing I've ever had as a committed atheist to a religious experience.
      
      Just putting this here: https://www.youtube.com/watch?v=r6w2M50_Xdk
      
      (Philhellenes' "Science saved my soul - from religion")
      

  • u/alexanderwales:

    Lovecraft suffered from extreme depression and suicidal tendencies, so it's not surprising that he would say something like that.
    
    I have a highly refined "shrug it off" ability that I use whenever things start to seem too meaningless. This wasn't really something that came naturally to me, but I worked to develop it over time. I think I'm a lot happier for that compartmentalization.
    

    • u/whywhisperwhy:

      Lovecraft absolutely had issues of all kinds and I think a lot of his ideas were sick / are now outdated. But this is one that I agree with and feel he expressed well. 
      
      And I usually work to stay busy and active (haven't quite mastered compartmentalization to the degree you mention, but I'm working on it because I also feel it's the only long-term solution), I just worry that it's basically just masking the issue.
      

  • u/xamueljones:

    Where you see things which don't care for you, I see ***opportunity!*** I mean it would be fantastic if there were other intelligences or a universe which cares about us like a benevolent god, but /u/Kerbal_NSA put it perfectly:
    
    > “When I see the vast cosmic expanse I know I am utterly dwarfed, a little speck to the side. And you know how that makes me feel? Powerful. Significant beyond description. For I have an incomprehensible amount of matter and energy before my eyes and its all for the taking. Every star, every planet, every molecule of interstellar gas will be ours to do with as we please. The entire universe is nothing but the clay we mould to our will.”
    
    When there's no competition, you are that more likely to **win**.
    
    Don't look for meaning, think about what you want and pursue it. I derive purpose and meaning from accomplishment and joy in striving to achieve my goals.
    
    But let's say that I'm silly for thinking that we can create our own purpose and meaning. I've had days (pretty rare though) where I thought that everything I've said above was stupid. However, I still believe that if I exist in a universe where humanity completely fails to survive and destroys itself in the next few years is inherently better than a universe where we never existed no matter how horrible life can get. It's *always* better to have tried than to give up, y'know? It's one of the few absolute rules I follow in my daily life. To me, accepting your statements feels too much like giving up and that feels like true failure rather than just simply failing to reach my goals. If you  try, failure's not completely certain, but to not even try makes it a 100% guarantee that you'll never get to do what you want.
    
    Hope my rambling helps!
    

    • u/None:

      /u/Kerbal_NSA was writing that in a story about a guy trying to become a paperclipper, but... yeah.
      
      <evil voice>You've learned well.</evil voice>
      

  • u/None:

    Excuse me, but I have work to do.  Will try to respond in full shortly.  In fact, I'm tempted to respond "in-character", except that no hold on I really am "Spiral" like that and don't just quote that show nonstop to sound cool.  Because infinite loops of TTGL quotes aren't really cool, they're just *true*.
    
    The full, complete, polished king of all Anti-Nihilist Rants might even be a good thing to post to the IEET once I finally have site access.
    
    Suffice that you should start with the following things you've probably read before:
    
    * HPMoR's "light in the universe" shpiel
    * The Fun Theory Sequence
    * I'm sure CS Lewis said something about how people are eternal splendors deep down.  I just can't fetch the quote at the moment.
    * TTGL quote that applies extra-strongly to living in a causal universe: "Love and spirit change the universe!"  The only thing Leeron got wrong is that they do so *through our actions*.
    

    • u/alexanderwales:

      > There are no ordinary people. You have never talked to a mere mortal. Nations, cultures, arts, civilizations - these are mortal, and their life is to ours as the life of a gnat. But it is immortals whom we joke with, work with, marry, snub and exploit - immortal horrors or everlasting splendors. This does not mean that we are to be perpetually solemn. We must play. But our merriment must be of that kind (and it is, in fact, the merriest kind) which exists between people who have, from the outset, taken each other seriously - no flippancy, no superiority, no presumption.
      
      ~C.S. Lewis
      

    • u/None:

      [deleted]
      

      • u/SvalbardCaretaker:

        Funnily enough, thats almost exactly the argument Immanuel Kant makes for human beings being moral objects.
        

  • u/BadGoyWithAGun:

    Nihilism is easy to start, but hard to finish. As far as I'm concerned, the statement "life is meaningless" is itself meaningless - if you find yourself depressed by the lack of a fundamental meaning, that's your fault for assuming something that obviously doesn't exist ought to.
    

  • u/None:

    Yep, that's human. Camus has a lot to say on the same topic: "One must imagine Sisyphus happy," etc. It's one of the reasons I'm really happy I discovered Stoicism: while before, I used to be filled with existential dread, now I've kinda … accepted that there is no meaning in the universe? To say "I'm having an existential crisis over the meaning of life" is akin to saying "I'm having an existential crisis over the dissolution of NaCl in H2O." And that's okay, yknow. That's okay.
    
    I guess Stoicism has helped, but I don't know if I can solely credit the change to that particular philosophy. It helped, sure, but is it a direct side effect? I guess I don't know what did this to me. I'm just happy that I don't have to worry too much about the big questions anymore.
    

• u/Magodo:

  Everyone should read *The Prince* by Machiavelli.
  
  Some choice quotes that feed the cynic in me;
  
  * love is preserved by the link of obligation which, owing to the baseness of men, is broken at every opportunity for their advantage; but fear preserves you by a dread of punishment which never fails.  
  
  * Therefore it is unnecessary for a prince to have all the good qualities I have enumerated, but it is very necessary to appear to have them.   
  
  * A prince, being compelled knowingly to adopt the beast, ought to choose the fox and the lion; It is necessary to be a fox to discover the snares and a lion to terrify the wolves.  
  
  
  The book is also completely free on Amazon and Project Gutenberg.
  

  • u/Jon_Freebird:

    It's also satire and dedicated to the people that broke both of his arms.
    

• u/None:

  Does anyone know if there have been any studies on helping ADHD/ADD kids/adults be more focused when reading or studying by having them use a tablet or other back-lit device? 
  
  I was talking to a woman this week who said she was never a big reader until she bought a tablet and tried the reading app, and was able to get her son to read in the same way. Both have ADHD, so I was curious if this is a known method already.
  

  • u/puesyomero:

    none that i found but i think the "ooh shiny!" factor has something to do with this :P either that or the expectation training we receive daily in associating tablets/phones with constant stimulation and distractions that when you use it for practical purposes it sticks?
    

    • u/None:

      Well I know I've read about backlit screens stimulating the brain to a higher level than other media do. It was in an article on sleep deprivation. I feel like that higher level of stimulation has got to have something to do with it. I'd love to get some kind of Actual Science to back me up, but unfortunately I don't know anyone who does ADHD research.
      

• u/xamueljones:

  If some ROB (Random Omnipotent Being) were to take this subreddit community, and anthropomorphize it into a human being, what would that being look and act like?
  
  If someone comes up with a really good description, I *might* commission an art piece of this hypothetical /r/rational person.
  

• u/None:

  How do you balance sleep and caffeine?  I've noticed that the more caffeine I drink, the worse I sleep the next night (ie: drink a double espresso and a Coke one day, involuntarily wake up at 6:00 next day after only getting to sleep at 2:00).  When I let up off the caffeine, I'm less able to make up for lack of sleep, but I get more in the first place.
  
  Currently I'm actually starting by throwing coffee out for a while and cutting back.  But I had quite liked coffee.
  

  • u/davidmanheim:

    I used to go in 3-4 week cycles; no caffeine, 1 cup a day, still sleepy so I have a second cup,  2 cups a day, still sleepy,  get 12 hours of sleep that night and go cold turkey, repeat.
    
    Now,  I'm less able to do this,  since kids dictate too much of my schedule.
    

  • u/ArgentStonecutter:

    I'm ADHD and have been self-medicating with coffee my entire life. If I don't have at least 4 cups a day I can't focus on anything *and* I have no energy. I don't have any problem sleeping - I'm a morning person, and rarely stay up past 10PM.
    
    The only time I've had that experience that people talk about where they can't sleep after having stimulants was when I went off coffee because I was taking ADHD medication (ritalin, focalin, adderal, I tried all three) and one time I had my Adderall dose calibrated too high and was actually getting a buzz off it.
    
    I went back to caffeine because I didn't feel they were doing any better a job. Also, I didn't like the side effects: particularly the one where I had to provide documentation that I was on a prescription stimulant after a drug test.
    

    • u/Jace_MacLeod:

      >I don't have any problem sleeping [with caffeine] - I'm a morning person, and rarely stay up past 10PM.
      
      *You lucky bastard.*
      

      • u/ArgentStonecutter:

        ADHD is not without its upsides, even if it does give me the attention span of a weasel on a sugar high.
        

• u/alexanderwales:

  I need some math help.
  
  Imagine a sphere (actually an oblate spheroid). Imagine a few thousand points on it. These points can be defined by polar coordinates (which requires a pole, a polar axis, a radius, and an azimuth, the first two of which are constant). All these thousands of points would be derived from some formula. For a simple example, let's say the radius increases by the [Fibonacci sequence](https://oeis.org/A000045) while the azimuth increases by the [sequence of primes](https://oeis.org/A000040). That would mean that our coordinates would be:
  
  * (0, 2°)
  * (1, 3°)
  * (1, 5°)
  * (2, 7°)
  * (3, 11°)
  
  And so on.
  
  So what I want is some mathematical way of generating polar coordinates such that a person looking at *only the marked locations on the sphere* would be able to work backwards and discover my method of generation. They should be able to do this even if they have no idea that I'm using a system of polar coordinates, they have no idea where I'm placing my pole or polar axis, and they don't have any idea what number system I'm using. The "discovered" formula should exactly match my formula with no ambiguity. Ideally, the formula would create repeating coordinates after generating a few thousand locations.
  
  The problem is, I don't know exactly what properties the formula needs to have in order for this to be true. I'm totally fine with two solutions to the formula, but three or higher doesn't work for my purposes.
  
  (Background for the story this is for can be [found here](https://www.reddit.com/r/alexanderwales/comments/3daqgk/making_a_solvable_puzzle/), though it shouldn't be at all necessary.)
  

  • u/None:

    You want the generator for a series of polar coordinates over a planet that's easiest to PAC-learn?  Because generalizing the rule from the examples is a statistical learning problem, so you have to avoid No Free Lunch situations by restricting the hypothesis class.
    

  • u/ArgentStonecutter:

    For the sake of the story I don't think you need to generate a formula that can do this, just generate a recognizable pattern. Even if they don't know their world is a sphere, something like an Archimedean spiral would work.
    
    Actually, I would work out a Lissajous figure with a known length, and then pick a sequence of points that follows the figure and is a large relatively prime fraction of the length. Say the length is 3,000,000 kilometers, then make the first point 2,930,000 kilometers in, then the rest of the points are ((n*293)%300)*10,000 kilometers along the path. This sequence should repeat after 300 steps, as if there is a device orbiting the planet and firing a transport beam every so often.
    

  • u/None:

    I kinda recommend asking /r/math. It would be a fun sort of challenge
    

• u/AmeteurOpinions:

  I read Terry Pratchett's *The Reaper Man* and while the wizarding sections were at best a distraction from Death it's still made it into my favorites. I also recently read *Man's Search For Meaning*, written by psychologist/therapist and **holocaust survivor** Victor Frankl. Interesting to read about the challenge of staying positive while suffering in a literal hell-on-earth.
  
  Those two books must form some sort of inoculation or antidote to existential stress. You'll be a happier person after reading them.
  

  • u/None:

    *Man's Search* was my personal introduction to Stoicism, waaay back when. I should give it a reread; Frankl gives some really sage life advice. (Pun intended.)
    

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