Three weeks from today, Google's artificial intelligence will go head-to-head with the real thing.

Over the past 18 months, researchers at DeepMind—a Google AI lab in the heart of London—have designed a computing system that can play the game of Go, the ancient Eastern version of chess. On March 9, in Seoul, South Korea, the DeepMind system—known as AlphaGo—will begin a five-game match against Lee Sedol, one of the very best (human) Go players on the planet. Over the last twenty years, machines have beaten the best human players at checkers, chess, Othello, Scrabble, even Jeopardy. But Go is still unconquered territory. Unlike chess, Go is so complex that no machine could cycle through all possible moves in a reasonable amount of time. In order to win, a machine must mimic the intuition of a human.

The match will serve as a bellwether for modern artificial intelligence.

For that reason, the match will serve as a bellwether for modern artificial intelligence. The techniques used by AlphaGo can be applied to so many other tasks, including image and speech recognition, natural language understanding, robotics, and perhaps even artificial common sense. There's also a $1 million prize at stake. The match will be live-streamed on YouTube. And WIRED will be on the ground in Korea covering this heavyweight bout from behind the scenes.

Who is likely to win? It depends on who you ask. Earlier this week, as reported by Geekwire, Demis Hassabis, who leads the DeepMind team, estimated that Go players give AlphaGo a mere five percent chance of winning. Lee Sedol himself has released a statement saying he's confident of winning. But Hassabis is just as confident in his artificial intelligence.

Ready, Steady, Go

But should he be? In October, during a behind-closed-doors match at the DeepMind offices in London, AlphaGo topped the European Go champion, Fan Hui. But the match in Korea is a very different prospect. Fan Hui is ranked 633rd in the world. Lee Sedol is ranked 5th. Last month, after revealing the win against Fan Hui, Hassabis acknowledged in an interview with WIRED that the match with Lee Sedol would be significantly more difficult. Fan Hui is the equivalent of a chess grandmaster, he said, while Lee Sedol is a super grandmaster.

Given their respective Go rankings, we can estimate Elo scores for each of them—a mathematical estimate of their relative skill levels. Fan Hui has an Elo score of roughly 2750, while Lee Sedol scores about 2940. Those scores mean Fan Hui has a pretty slim chance of even winning a single game against Lee Sedol over a five game match.

Fan Hui also didn't stand much of a chance against AlphaGo, which won their match five-nil. He's now an adviser on the DeepMind (he will be in Korea with Hassabis and other DeepMind engineers). Since the match in October, Hassabis and crew have continued to improve AlphaGo. That's a good four months of additional advances.

What's more, AlphaGo will take on Lee Sedol backed by some serious infrastructure. Hassabis and crew originally built AlphaGo to run on a single fairly ordinary computer. For the match against Fan Hui, they upgraded to a network of machines that includes 1,200 central processing chips and about 170 cards packed with graphics processing units, or GPUs. These chips were originally designed for games and other highly graphical software applications but have proven quite adept at deep learning and reinforcement learning, two forms of AI used by AlphaGo. For the Korea match, Hassabis says, he and his team are "laying down their own fiber" so that they have a good connection to a Google data center that holds such hardware. "You've got a flexible supercomputer on tap that you can just dip in or dip out of," he says.

These AI systems are particularly powerful because they can learn to play Go on their own. That network of GPUs analyzes mountain of human Go moves and then, in essence, repeatedly plays itself in an effort to hone its skills. Prior to the rise of deep learning and reinforcement learning, a AI system didn't stand a chance against someone like Lee Sedol. But these technologies have completely changed the equation. Rémi Coulom, the French researcher behind what was previously the world’s top artificially intelligent Go player, predicts that AlphaGo will win.

As Geekwire points out, popular opinion is mixed. At the online bitcoin betting site BitBet, punters favor Sedol. But at GoodJudgment, prognosticators give AlphaGo the edge—only just.