10 March 2016

Google's AlphaGo beats a Go champion

For awhile now artificial intelligence has been really good at generating winning game play based on the rules of games. Tic tac toe, checkers, sudoku, chess; in just a few short weeks, one of my students in DSP made an AI that was very good at connect-4. (It didn't beat me-- I was only willing to play it once, though!) However, checking the outcome of every possible move will never be possible for a game like Go unless a completely new paradigm of computing comes about. Still, Google has designed a player that can win. Instead of checking the outcome of moves, AlphaGo learns how best to move based on historical data of real games and its own simulations of games. It keeps trying out new games and it sees what happens. Then it keeps a memory of what to play based on the board configuration using deep learning networks, a sort of dimensionality reduction technique that encodes this experience in several layers of equations that can take any input and give the output of what to play next.

This discussion of what AlphaGo means to the future of AI takes several perspectives on what the implications of a Go-winning AI really are. I agree most with Professor Brunskill. She says, "Go is a fixed game: The rules, possible moves and observable information about the game are all prespecified. AlphaGo is not allowed to invent a new move, nor gain new insight by quizzing its opponent. Fortunately the real world is not like this. From the Hubble telescope to vaccinations, people constantly invent new ideas that allow us to transform how we monitor and shape the universe and achieve previously unimaginable outcomes."

I would add that furthermore, not only because humankind can innovate and create new realities do the rules of life change out from under us. New challenges face us every day, like the disappearance of the Malaysian Airlines flight MH370 two years ago this month, or the Zika virus, or locked cell phones of terrorists. Humans have evolved over centuries to face this adversity head-on and adapt for survival; this is exactly why we do innovate, create new measurement technologies, new drugs, and new security protections. Hopefully computers will be able to help us with this process in the not-too-distant future. But before that, machine learning research needs to face the hurdle of learning in a dynamic world.

13 November 2015

Chess game with the Devil

I had been meaning to read this article about Terry Tao for the last several months and I finally got around to it on a cozy Friday night at home. I really like it for the way it describes him as such a genial and friendly guy, and the story it tells about even Terrence Tao being intimidated when he arrived at Princeton. My favorite quote though is this one about what it's like to be a mathematician:

"The true work of the mathematician is not experienced until the later parts of graduate school, when the student is challenged to create knowledge in the form of a novel proof. It is common to fill page after page with an attempt, the seasons turning, only to arrive precisely where you began, empty-handed — or to realize that a subtle flaw of logic doomed the whole enterprise from its outset. The steady state of mathematical research is to be completely stuck. It is a process that Charles Fefferman of Princeton, himself a onetime math prodigy turned Fields medalist, likens to ‘playing chess with the devil.’ The rules of the devil’s game are special, though: The devil is vastly superior at chess, but, Fefferman explained, you may take back as many moves as you like, and the devil may not. You play a first game, and, of course, ‘he crushes you.’ So you take back moves and try something different, and he crushes you again, ‘in much the same way.’ If you are sufficiently wily, you will eventually discover a move that forces the devil to shift strategy; you still lose, but — aha! — you have your first clue."

20 October 2015

Einstein memorial

Last weekend I was in DC and I visited the Einstein memorial along with all the other national memorials on or near the national mall. There are so many great quotes memorialized on these walls, but this is one of my favorites:

"The right to search for truth implies also a duty: one must not conceal any part of what one has recognized to be true.”

23 September 2015

Probability in your profession

What does probabilistic terminology really mean when people use it in your field?

Here is my favorite (image from the linked site above, used without permission, but for educational purposes obviously):

In mine we say "with probability 1-delta" and that's exactly the probability we mean. Except don't calculate delta.

11 August 2015

Gömböc

I recently learned that when you win the Smale Prize you get a gömböc!

My favorite part of the gömböc is its relationship to a turtles' righting response: "The balancing properties of the gömböc are associated with the 'righting response', their ability to turn back when placed upside down, of shelled animals such as tortoises and beetles."

24 July 2015

the entry in which I admit I am reading the phantom tollbooth

"That's absurd," objected Milo, whose head was spinning from all the numbers and questions.

"That may be true," [the Dodecahedron] acknowledged, "but it's completely accurate, and as long as the answer is right, who cares if the question is wrong?"

20 April 2015

everyone gather round for a physics joke

Thanks to my friend Jim Hall and this reddit.

Heisenberg, Schrödinger, and Ohm are together in a car, driving down the road.

They get pulled over. Heisenberg is driving and the cop asks him "Do you know how fast you were going?" "No, but I know exactly where I am" Heisenberg replies. The cop says "You were doing 55 in a 35." Heisenberg throws up his hands and shouts "Great! Now I'm lost!"

The cop thinks this is suspicious and orders him to pop open the trunk. He checks it out and says "Do you know you have a dead cat back here?" "We do now, asshole!" shouts Schrödinger.

The cop moves to arrest them. Ohm resists.