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bananas

(27,509 posts)
Sat Oct 17, 2015, 04:24 AM Oct 2015

The biggest mystery in mathematics: Shinichi Mochizuki and the impenetrable proof

http://www.nature.com/news/the-biggest-mystery-in-mathematics-shinichi-mochizuki-and-the-impenetrable-proof-1.18509?WT.mc_id=SFB_NNEWS_1508_RHBox

The biggest mystery in mathematics: Shinichi Mochizuki and the impenetrable proof

A Japanese mathematician claims to have solved one of the most important problems in his field. The trouble is, hardly anyone can work out whether he's right.

Davide Castelvecchi
07 October 2015 Corrected: 07 October 2015, 15 October 2015

Sometime on the morning of 30 August 2012, Shinichi Mochizuki quietly posted four papers on his website.

<snip>

In December, the first workshop on the proof outside of Asia will take place in Oxford, UK.

<snip>

Fesenko has studied Mochizuki's work in detail over the past year, visited him at RIMS again in the autumn of 2014 and says that he has now verified the proof. (The other three mathematicians who say they have corroborated it have also spent considerable time working alongside Mochizuki in Japan.)

<snip>

But so far, the few who have understood the work have struggled to explain it to anyone else. “Everybody who I'm aware of who's come close to this stuff is quite reasonable, but afterwards they become incapable of communicating it,” says one mathematician who did not want his name to be mentioned. The situation, he says, reminds him of the Monty Python skit about a writer who jots down the world's funniest joke. Anyone who reads it dies from laughing and can never relate it to anyone else.

<snip>

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The biggest mystery in mathematics: Shinichi Mochizuki and the impenetrable proof (Original Post) bananas Oct 2015 OP
Monty Python's Flying Circus - World's Funniest Joke bananas Oct 2015 #1
I did a Ph.D. In algebraic geometry - same field as Grothendieck who was Lucky Luciano Oct 2015 #2
If it's so difficult, does it matter? Renew Deal Oct 2015 #3
A good question that's been asked for millinia about some other closet doodlers such as sorechasm Oct 2015 #6
Matter to whom? bemildred Oct 2015 #7
All knowledge has a solid use, assuming you can get to the barebones of it Hydra Oct 2015 #10
What we could do with it would entirely depend on the nature of the proof struggle4progress Oct 2015 #14
+1. nt bemildred Oct 2015 #4
Mind boggling. GoneFishin Oct 2015 #5
You can create your own impenetrable paper here central scrutinizer Oct 2015 #8
If the answer sharp_stick Oct 2015 #9
Not Even Wrong: Latest on abc struggle4progress Oct 2015 #11
The ABC Conjecture has not been proved struggle4progress Oct 2015 #12
I gave his his 45 page overview a quick look struggle4progress Oct 2015 #13
He uses l* on the very next page and page 6 at least. Lucky Luciano Oct 2015 #15
Well, you looked more closely than I did, but it reinforces what I said about organization: struggle4progress Oct 2015 #16
He still deserves some benefit of the doubt. Lucky Luciano Oct 2015 #17
Nothing I say here will affect his reputation one way or the other struggle4progress Oct 2015 #18
kicked Blue_Tires Oct 2015 #19

Lucky Luciano

(11,250 posts)
2. I did a Ph.D. In algebraic geometry - same field as Grothendieck who was
Sat Oct 17, 2015, 05:34 AM
Oct 2015

...referenced in the article. I used a lot of his results - the basis for much of my work really. Algebraic geometry is super fucking hard abstract shit - so is number theory. The two fields are the hardest in all of math. I can see why others would likely find this new work impenetrable. The latest stuff really is backing up against the limits of human intellect. Like the article says, it would take a grad student 10 years to begin to touch this guy's paper. This guy could only do the work by isolating himself for total concentration...which is why I left academia. I wanted a more fun lifestyle.

Renew Deal

(81,847 posts)
3. If it's so difficult, does it matter?
Sat Oct 17, 2015, 07:45 AM
Oct 2015

Why spend time on it? Does it have any human use? I know I'm asking the "never use it in real life" question. Does it matter if this problem is ever solved?

sorechasm

(631 posts)
6. A good question that's been asked for millinia about some other closet doodlers such as
Sat Oct 17, 2015, 09:22 AM
Oct 2015

Pythagoras, Hidab al-jabr wal-muqubala, Fibonacci, Gallileo, Newton, Einstein and thousands more we've never heard of who contributed to our universal understanding.

2000 years of Applied Scientists, Inventors, and Capitalists would have been lost without those contributions, often anonymous.

bemildred

(90,061 posts)
7. Matter to whom?
Sat Oct 17, 2015, 09:26 AM
Oct 2015

It is very fundamental, I can't think of anything more fundamental and yet more opaque than number theory, and yet all of our science is built on it. I am very interested to know what he is doing poking about in the foundations and set theory and the nexus between summation and multiplication, but I doubt I am up to the job, so I'll have to wait.

Hydra

(14,459 posts)
10. All knowledge has a solid use, assuming you can get to the barebones of it
Sat Oct 17, 2015, 10:52 AM
Oct 2015

Our understanding of Quantum stuff is still pretty clunky, but we've been making progress on it and getting some amazing results. Getting "abstract" math sorted out will be similar- we will be able to calculate things with far more precision and efficiency.

struggle4progress

(118,237 posts)
14. What we could do with it would entirely depend on the nature of the proof
Sat Oct 17, 2015, 04:05 PM
Oct 2015

The computational complexity of number theory results from the relationships between addition and multiplication: in general, one does not understand much about the prime divisors of a + b in relation to those of a and b considered separately. An effective proof of the conjecture might be expected to yield good algorithms, though a proof by contradiction might not. Number theory can sometimes be extremely important in other branches of mathematics and in modern physics

Beyond that, there are also aesthetic attractions

struggle4progress

(118,237 posts)
11. Not Even Wrong: Latest on abc
Sat Oct 17, 2015, 11:15 AM
Oct 2015
... His argument for abc involves a new set of ideas he has developed that he calls “Inter-Universal Teichmuller Theory” (IUTeich). These are explained in a set of four papers with a total length over 500 pages. The papers are available here, and he has written a 45 page overview here ... In principle one should just be able to go line by line through the four papers and check the arguments, but if one tries this, one runs into the problem that they depend on a long list of “preparatory papers”, which run to yet another set of more than 500 pages. So, one is faced with an intricate argument of over 1000 pages, involving all sorts of unfamiliar material. That people have thrown up their hands after struggling with this for a while, deciding that it would take years to figure out, is not surprising ...
http://www.math.columbia.edu/~woit/wordpress/?p=6514

The Paradox of the Proof
By Caroline Chen
MAY 9, 2013
... “His other papers – they’re readable, I can understand them and they’re fantastic,” says de Jong, who works in a similar field. Pacing in his office at Columbia University, de Jong shook his head as he recalled his first impression of the new papers. They were different. They were unreadable. After working in isolation for more than a decade, Mochizuki had built up a structure of mathematical language that only he could understand. To even begin to parse the four papers posted in August 2012, one would have to read through hundreds, maybe even thousands, of pages of previous work, none which had been vetted or peer-reviewed. It would take at least a year to read and understand everything. De Jong, who was about to go on sabbatical, briefly considered spending his year on Mochizuki’s papers, but when he saw height of the mountain ... “I decided, I can’t possibly work on this. It would drive me nuts” ...

struggle4progress

(118,237 posts)
12. The ABC Conjecture has not been proved
Sat Oct 17, 2015, 11:36 AM
Oct 2015
... proof is a social construct: it does not constitute a proof if I’ve convinced only myself ... It only constitutes a proof if I can readily convince my audience ... Moreover, if I claim to have proved something, it is my responsibility to convince others I’ve done so ...

... nobody understands what he’s talking about, even people who really care .. and his write-ups don’t help.

... here’s an excerpt from the very beginning of the .. final paper:
The present paper forms the fourth and final paper in a series of papers concerning “inter-universal Teichmuller theory”. In the first three papers of the series, we introduced and studied the theory surrounding the log-theta-lattice, a highly non-commutative two-dimensional diagram of “miniature models of conventional scheme theory”, called ?±ell NF-Hodge theaters, that were associated, in the first paper of the series, to certain data, called initial ?-data. This data includes an elliptic curve EF over a number field F , together with a prime number l ? 5. Consideration of various properties of the log-theta-lattice led naturally to the establishment, in the third paper of the series, of multiradial algorithms for constructing “splitting monoids of LGP-monoids”.

If you look at the terminology .. you .. find many examples of mathematical objects that nobody has ever heard of: he introduces them in his tiny Mochizuki universe with one inhabitant ...


http://mathbabe.org/2012/11/14/the-abc-conjecture-has-not-been-proved/

struggle4progress

(118,237 posts)
13. I gave his his 45 page overview a quick look
Sat Oct 17, 2015, 03:45 PM
Oct 2015

I'm nothing like an expert in the field, but one can often tell something from style and organization

On page one, he says (for example) "For convenience, we shall use the notation l* := (l - 1)/2" -- but then does nothing with this entirely trivial definition so far as I can tell. A nonexpert like myself can only be struck by the way the material apparently flits, without plot, between apparently impenetrable jargon and rather commonplace mathematics. Unfortunately, this is really not a good sign: it is, in fact, typical of papers written by cranks purporting to have proven difficult theorems. My guess is that his huge stack of paper would be waved off without second thought, but for the fact that he has done some stellar mathematical work in the past

We know that excellent mathematical work need not be immediately comprehensible (from the story of Galois, say); that an epochal paper may be short on proof and long on suggestive conjecture (from the story of Riemann, say); that brilliant intuition itself can be valuable (from the story of Ramanujan, say); that good work can remain controversial and will not necessarily meet instant acclaim (from the story of Cantor, say); and so on. But we also know that good minds are not immune to mental breakdown (from the story of Godel, say)




Lucky Luciano

(11,250 posts)
15. He uses l* on the very next page and page 6 at least.
Sat Oct 17, 2015, 05:05 PM
Oct 2015

He used them in the formulas. He did it because the typeset would get annoying (you will see what I mean).

A quick skim has him mentioning a lot of the mathematical constructs I did in grad school studying algebraic geometry...I have forgotten nearly all of it though. Seeing this reminds me how bloody hard it all is.

He would have picked off as a crank a long time ago had he been cranking on this. Not saying his work lacks errors, but he is legit.

struggle4progress

(118,237 posts)
16. Well, you looked more closely than I did, but it reinforces what I said about organization:
Sat Oct 17, 2015, 08:07 PM
Oct 2015

the proper place for a trivial definition would be closer to the actual first use, in a form like "where l* = &c"

The same might be said of his sudden introduction of the Gaussian integral on page 4, which then seems to be dropped

There are other objective reasons for concern: ... he has declined invitations to talk about it elsewhere. He does not speak to journalists; several requests for an interview for this story went unanswered. Mochizuki has replied to e-mails from other mathematicians and been forthcoming to colleagues who have visited him, but his only public input has been sporadic posts on his website. In December 2014, he wrote that to understand his work, there was a “need for researchers to deactivate the thought patterns that they have installed in their brains and taken for granted for so many years” ... This statement about the necessity of breaking mental habits may, of course, be true -- but it is also unfortunately the well-known standard complaint of cranks

Simple statements can certainly have long proofs: one thinks of the Feit-Thompson theorem, or the four-color theorem, or the classification of finite simple groups. The latter two examples, however, both raised the question, whether one really has a proof, if nobody can survey it. That completely correct proofs may seem initially impenetrable, until the apparently tricky parts suddenly become clear, is shown by the initial reception to Apéry's theorem. But the remark, that there is no better feeling in the world that the one you have between the time you first prove a theorem and the time you find the first mistake, has a certain sagacity. And there is a certain history of good mathematicians announcing proofs that have never been accepted: ten or fifteen years ago, I heard a good number theorist discuss a purported proof of the Riemann hypothesis, which involved such heavy layers of abstraction that in the end it was really rather unclear exactly what had been proved

The interplay between addition and multiplication is very tricky, as one discerns from the effort apparently needed to prove results approaching (say) the twin primes conjecture or Goldbach's conjecture. If Mochizuki has really provided new foundations that make possible a proof of abc, someone should be able to use that environment to obtain simple proofs of many less difficult theorems

Lucky Luciano

(11,250 posts)
17. He still deserves some benefit of the doubt.
Sun Oct 18, 2015, 05:37 PM
Oct 2015

A few others, it seems, did invest done time to get through a lot if his work. There must be something there. I wouldn't be surprised if there are a couple bugs to iron out though. Still, he seems less crazy than Perleman after the Poincaré conjecture proof - which also took some years to verify.

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