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350-Year-Old Newton's Puzzle Solved By 16-Year-Old
First time accepted submitter johnsnails writes "A German 16-year-old, Shouryya Ray, solved two fundamental particle dynamic theories posed by Sir Isaac Newton, which until recently required the use of powerful computers. He worked out how to calculate exactly the path of a projectile under gravity and subject to air resistance. Shouryya solved the problem while working on a school project. From the article: 'Mr Ray won a research award for his efforts and has been labeled a genius by the German media, but he put it down to "curiosity and schoolboy naivety." "When it was explained to us that the problems had no solutions, I thought to myself, 'well, there's no harm in trying,'" he said.'"
We all had that moment in school when a teacher would pose an "impossible" problem, thought to ourselves "Well, they've never faced ME before!", spent a few minutes toying with it and finally giving up. This kid...did not.
Kudos all around! The rest of your life will, unfortunately, now no longer live up to something you accomplished when you were 16.
The article itself is mathless. It doesn't tell you what the solution was, or even present the exact problem that was solved.
The problem he solved is determining the exact path of a projectile, when accounting for air resistance. The drag coefficient for air resistance depends nonlinearly on velocity, so when it is included in the model the equations become difficult to solve (previously impossible, but apparently now done. Though I haven't found any links to his actual work). Here is an example of setting up the problem, and then solving it numerically.
You forgot a lot of things:
-gravity is not a constant vector force downward. It is a radial force inward toward the center of the Earth, and its intensity varies with altitude.
-air resistance is not constant either. It depends on air pressure which varies with altitude as well.
-air resistance is not perfectly proportional to v^2, especially at transonic and supersonic speeds.
-if the projectile is spinning, it may cause a net aerodymamic force in a direction other than -v. Like a curveball.
-the earth is a spinning frame of reference, which results in various annoying effects.
-the air is not necessarily stationary. Wind exists.
and so on.
But we don't know whether this dude accounted for any of this stuff or not, because the goddamn article doesn't tell us.
These stories about overwhelming acts of personal genius, especially stories that lack the details of the alleged act, are, without memorable exception, false. But we all like a good story about an under-caste upsetting gray hairs and the established order of things.
Think about that for a moment. A story supposedly lionizing science lacking the most basic facts that would permit substantial verification, or falsification, of that science. This is just flash journalism at work.
Another famous example is Grigori Perelman who solved the Poincaré conjecture - with hundreds and hundreds of pages of mind-numbingly dense mathematics vs computer search.
Perelman's three primary papers ("The entropy formula for the Ricci flow and its geometric applications" http://arxiv.org/abs/math.DG/0211159, "Ricci flow with surgery on three-manifolds" http://arxiv.org/abs/math.DG/0303109, and "Finite extinction time for the solutions to the Ricci flow on certain three-manifolds" http://arxiv.org/abs/math.DG/0307245) on modifying Hamilton's Ricci flow program to deal with singularities and proving Thurston's geometrization conjecture only span 68 pages, with the actual proofs/meaningful remarks comprising about 45 pages of that.
I was not a prodigy, but a really smart kid who was in many environments with prodigies or near prodigies.
My experience has been that most pre-teen children with this history don't understand the material very well, and there tends to be a lot of exaggeration about it. Smart kids are good at mimicking things and that is all that is really need to "do" the first year or two of college math.
Occasionally, but very occasionally you get someone really young who later goes on to do decent, or even more rarely great things, like Norbert Wiener or Terry Tao. But I would like to hear those people give their opinions of the depth of their understanding at that age.
I knew Nadine Kowalsky, who in HS would essentially just remember everything she heard in class and got 100 on every exam. (She wasn't the only one though. I knew a number of other people like that though that didn't do as well as Nadine did.) She later went on to get a Ph.D. from Chicago and published her thesis in the Annals of Math. That is a journal most mathematicians can't get a paper in. Like publishing in Nature or Science. Nadine was the real deal, but sadly she died of cancer not long after finishing her Ph.D. But I don't believe that Nadine was doing calculus until she was 15. And that was certainly on purpose. She, and her parents apparently, knew what was a good idea to do, and not to do, with a super smart kid. (This last sentence is conjecture on my part.)
But I think most cases of pre-teens you hear about are really not what they are made out to be. Once you get to 12 or 13 those, I think things do change a lot.
I was doing advanced Geometry and Algebra at age 8, yes I'm a slow fool compared to this kid. but it's mostly the quality of teachers (his dad) and the willingness to keep giving a kid what they want and challenging them.
The american school system is designed to DISCOURAGE this. Smart kids are told to be happy with the A they got without trying. If they challenge their teachers knowledge they are told they are wrong. Mostly because Grade-High-school education in the USA is simply following a lesson out of a book and not teaching it from an expert. the Gym teacher teaches computer class, The English teacher teaches Chemistry, and all of it creates a ho hum boring as hell experience for the children.
Here in the USA we do NOT want geniuses, we want good factory and office workers. Mediocre will not challenge authority.
yes I am jaded at the education system here. I was one of them that got bad grades because the teachers were idiots. I challenged my math teacher who could not believe that a kid can do multiplication and simple geometry in his head. I proved it on several occasions, but I was given failing grades for not doing the busywork of writing it all out. Plus I refused to learn his technique. It sucked and was harder than what I was using that came from college text books. So I ended up being a pissed off moody kid hating the education system because all I saw was idiots and morons trying to tell me they knew more than Me and I knew that they were wrong. I was reading at a 14th grade level when I was 12 years old. I read 1984 and understood the concepts and hidden meanings. I was devouring Vonnegut with a passion. I was told that the books were "too grown up for me" Everyone talked down to me and all it did was piss me off.
Sadly I did not have rich parents, so I had to suffer through the waste of time that the American Public School system is. College I slept through and aced it, at least they were not morons requiring me to turn in worthless busy work. It was in college where I ran into real education, educators that actually knew what they were talking about and would actually hold a discussion with me and help me learn more.
This is the problem here in the USA. If you are smart, you have a sack put over your head to slow you down to match the rest of the other students.
Do not look at laser with remaining good eye.
That helps a little, but still doesn't really clarify completely what he did. I'll explain a little about what I know about the projectile problem and what I can figure out about what he might have accomplished here.
In the Principia, Newton poses three closely related problems. One is projectile motion under the influence of a frictional force that's proportional to velocity (book II, section I). Next he considers the case where the friction is proportional to the square of the velocity (book II, section II), and finally the case where it's of the form av+bv^2, where a and b are constants (book II, section III). Let's call these cases 1, 2, and 3.
Case 1 is pretty straightforward. The x and y motions are decoupled, and each of the motions is governed by a first-order, linear, inhomogeneous equation.
Case 2 is actually of more physical interest than case 1 for most real-world projectiles. For example, when you toss a baseball in air, its Reynolds number is about 10^4 or 10^5, and in that regime, a force proportional to v^2 is a pretty decent approximation. There is a well known closed-form solution for the one-dimensional subcase (I actually had a student a few years back who figured it out for herself, which was impressive), which is y=A ln[cosh(t sqrt(g/A))].
A hint is that this page has a photo of him holding up a large sheet of paper with his closed-form solution on it. The equation is clearly visible, and reads g^2/(2u^2)+(alpha g/2)[v sqrt(u^2+v^2) / u^2 + arsinh |v/u|] = const. The notation isn't explained, but clearly u and v are the components of some vector, probably the velocity vector. If so, then the constant alpha has to have units of inverse meters.
This makes me think that what he's solved is the full two-dimensional version of case 2. It can't be case 3, because besides g there is only the one constant alpha appearing in his equation. If you write down the equation of motion, a=F/m=(mg-bv^2)/m=g-(b/m)v^2, the constant that naturally occurs is b/m, which has units of inverse meters. It also makes sense that his solution has a hyperbolic trig function in it, since the y(t) for the one-dimensional version of case 2 has a hyperbolic trig function in it.
If my interpretation is right, then you should get a correct one-dimensional result from his equation when u=0. Unfortunately his equation blows up to infinity in that case, so I'm not sure how to extract any sane interpretation from it. By setting alpha=0, you should also get the case with zero friction. That does sort of make sense, since it says u is a constant, which it should be in that case.
It would be interesting to see if my interpretation is right by doing a numerical simulation and seeing if his expression really does seem to be a constant of the motion.
One thing to point out is that he may not have actually solved the full problem as set by Newton. He hasn't found the equation of the trajectory in closed form (which I think was what Newton was most interested in), and he also hasn't found the position in closed form as a function of time. (This is all assuming my interpretation is right.)
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I have to agree with your comment about learning DE, I failed differential equations the first time I took the class (a D-grade) I was taking engineering course work at the time that required them - and what they actaully "meant" clicked in an electrical networks class - when I took the class again (my university had a 1 time grade forgiveness policy) I got an A - it seemed trivial and simple the second time around in a different context. I general I have mathematics makes mroe sense to me personally when I can relate it to a real world problem - Mathematics taught as rote learning is a horrible thing - some of us can't do it that way....
"Here in the USA we do NOT want geniuses, we want good factory and office workers. Mediocre will not challenge authority."
Exactly. And I tell you, is the same thing here in Brazil.
Religion: The greatest weapon of mass destruction of all time
...it does publish great papers, but does require something of a personal connection to get into... Same for The Proceedings of the National Academy of Sciences
Actually, this isn't so true of PNAS any more. One of the previous editors decided in the late 1990s to raise the quality prestige of the journal by accepting more papers through a traditional peer-review route, as opposed to NAS members "communicating" or "contributing" articles (which would often have minimal peer review). This was very successful, and now most articles in PNAS get in through the front door, and they're slowly eliminating the back doors. The overall quality is pretty good - not as high-impact as Science or Nature or some of the top specialty journals, but it's definitely a journal that researchers are excited about publishing in if they can't get into the top tier. The fact that they're not part of Elsevier or one of the other big commercial publishers, and their open-access fee is very reasonable, is an added bonus. (Disclaimer: I've published there, so I'm not entirely unbiased.)
Now, as with any journal, knowing the right people always helps - sadly, this is true at any level.
Exactly. As a kid, I had a dog that understood when I threw a ball up on the roof of our garage, which caused it to disappear from her sight, that it would roll along the slope of the roof and and reappear further down the roofline. She actually got fairly good at predicting where the ball would reappear, repositioning herself along its path over time so she would meet it at its eventual drop point. Does that mean my dog understood calculus, or solved Newton's problem? Well, she recognized a pattern and was able to apply a repeatable solution.
That tells me that the brain is capable of recognizing complex patterns around us, and is actually already very capable of deriving and applying practical solutions. ("So easy a dog could do it.") Applying abstract mathematical models to them, however, is not so easy.
What I'd be most interested in in this whole saga is "what methods did his father use to teach him math?" Obviously they were highly effective.
John