Wednesday, February 27, 2008

Kyosito Ito - our Mystery Mathematician - and our Winners!

Kyosito Ito

I chose Dr. Ito for many reasons. Here are a couple--

(1) He is the father of stochastic analysis/stochastic differential equations, which, for me meant that he found precise mathematical equations and formulas to describe apparently random fluctuations and motion like Brownian movement. I remembered taking a grad course in Ergodic theory which demonstrated to me how there can be order in chaos.

(2) This quote in his bio made an impression on me:

"Although today we see this paper as a fundamental one, it was not seen as such by mathematicians at the time it was published. Ito, who still did not have a doctorate at this time, would have to wait several years before the importance of his ideas would be fully appreciated and mathematicians would begin to contribute to developing the theory."
I believe it is not unusual that important theories and discoveries have been ignored or dismissed by 'experts' who don't want to take the time to consider that someone of lesser renown might have actually discovered something they could not! Years or generations later, the research often receives the recognition it deserves.

However, Ito didn't respond with bitterness:

"When I first set forth stochastic differential equations, however, my paper did not attract attention. It was over ten years after my paper that other mathematicians began reading my "musical scores" and playing my "music" with their "instruments."
And now for our winners...
Those who correctly identified Professor Ito (and selected comments/anecdotes):

"Kiyosi Ito --
I have an interest in the history of mathematics and the contribution of great mathematicians. Even when I do not completely understand their contributions (which happens all too frequently,alas!), following that history puts mathematics into a beautiful, cohesive whole. Euler remains my favorite mathematician for this reason because he did just that - he put so many prior contributions into an understandable whole that we still use today. Of course, he made some pretty outstanding contributions in his own right. -- Looking at mathematics though an historical perspective from its earliest roots of simple counting - i.e cave drawings of the successful hunt - to the establishment of number systems and their expansions to meet the problem solving needs of society - is a wonderful guide line for what we should be teaching and when."
Thank you, Hypatia for your continued interest in the recognition of some of the world's greatest mathematicians and this contest. You are one of our most consistent winners!


"Was it the same guy who found a way

to divide time into infinitely small
chunks so that rocket trajectories
could finaly be calculated in an
uninterrupted continuum?
If so it must be: Kiyosi Ito"

I'd also like to personally thank Florian for excellent suggestions to improve our contest, some of which I've begun to implement!

Totally Clueless

"The mystery mathematician is Ito san of Ito calculus fame. I remember

struggling through stochastic differential equations in grad school. I
think his work might have had an influence on the work of Black and
Sholes on the pricing of options on the stock market."


Kiyosi Ito (last o should have circumflex).

I only know of him because he won the Gauss Prize in 2006; his work is outside my expertise.

The March 2007 volume of The Japanese Journal of Mathematics had a number of articles devoted to Ito's life & mathematics (including a photo). There are a few interesting anecdotes: a) Ito, about 90 years old at the time, expresses regret that his mentor had recently died at 100, and so did not hear of the award and could not enjoy the success of his student. Mathematics contributes to longevity perhaps ? b) Ito observed the good sense of there being no age limit on awarding the Gauss Prize (as for the Fields medal) since it often takes a long time for applied mathematics to be recognized. c) It is recalled that in the late 1930s, while working for a Japanese statistical bureau and before obtaining a doctoral degree, he wrote two fundamental papers. Since no copy machines were available, he needed to copy by hand in the library a text of P. Levy that included ideas he developed, added to and made rigorous.

Kevin added a fascinating extra piece which could easily be a discussion on its own:

As an interesting aside, in the same journal issue, there are some articles about Teiji Takagi. An interesting quote from one of them:

There is an interesting historical document. A copy of a Japanese
journal, The Journal of Tokyo Suugaku Kaisha (Tokyo Mathematical Company),
No.44, 1882, has an appendix1(pp. 24–26) which reports the fifteenth meeting
on Japanese translation of the word ‘arithmetic’. The point of the argument was
whether they should choose a word meaning ‘art’ or ‘science’ for ‘arithmetic’.
Kikuchi strongly appealed for ‘art’ and finally won 9 votes among 14 committee
members excluding the chairman. Since then the word ‘san jutsu’ in Chinese
characters, which was originally found in old Chinese books of mathematics, is
still used to mean ‘arithmetic’ in Japanese.

Congratulations to our winners and a deep expression of gratitude to our readers for their continued support of my efforts.

Finally, only a few hours left to vote in our survey! I will try to post the final results and a brief discussion on Friday, Feb 29th as we leap into the future!


Florian said...

That was a cool Contest Dave!

I'm glad I could contribut a
tiny bit to your great site.

Now .. who will be the next
mystery mathematician?

Dave Marain said...

Thanks, Florian! You were a big part of it.

I'm working on the next mathematician but that probably won't be up until next week.