IBM Deep Blue
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Deep Blue was a chess-playing computer developed by IBM. In 1997, the machine defeated world champion Garry Kasparov.
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[edit] History
The computer system dubbed "Deep Blue" was the first machine to win a chess game against a reigning world champion (Garry Kasparov) under regular time controls. This first win occurred on February 10, 1996. Deep Blue - Kasparov, 1996, Game 1 is a famous chess game. However, Kasparov won 3 games and drew 2 of the following games, beating Deep Blue by a score of 4–2. The match concluded on February 17, 1996.
Deep Blue was then heavily upgraded (unofficially nicknamed "Deeper Blue") and played Kasparov again in May 1997, winning the six-game rematch 3.5–2.5, ending on May 11th, finally ending in game six. Deep Blue thus became the first computer system to defeat a reigning world champion in a match under standard chess tournament time controls.
The project was started as "ChipTest" at Carnegie Mellon University by Feng-hsiung Hsu; the computer system produced was named Deep Thought after the fictional computer of the same name from The Hitchhiker's Guide to the Galaxy. Hsu joined IBM (Research division) in 1989 and worked with Murray Campbell on parallel computing problems. Deep Blue was developed out of this. The name is a play on Deep Thought and Big Blue, IBM's nickname.
The system derived its playing strength mainly out of brute force computing power. It was a massively parallel, 30-node, RS/6000, SP-based computer system enhanced with 480 special purpose VLSI chess chips. Its chess playing program was written in C and ran under the AIX operating system. It was capable of evaluating 200,000,000 positions per second, twice as fast as the 1996 version. In June 1997, Deep Blue was the 259th most powerful supercomputer, capable of calculating 11.38 gigaflops, although this did not take into account Deep Blue's special-purpose hardware for chess.
The Deep Blue chess computer which defeated Kasparov in 1997 would typically search to a depth of between 6 and 12 ply to a maximum of 40 ply in some situations. An increase in search depth of one ply corresponds on the average to an increase in playing strength of approximately 80 Elo points.
Deep Blue's evaluation function was initially written in a generalized form, with many to-be-determined parameters (e.g. how important is a safe king position compared to a space advantage in the center, etc.). The optimal values for these parameters were then determined by the system itself, by analyzing thousands of master games. The evaluation function had been split into 8,000 parts, many of them designed for special positions. In the opening book there were over 4,000 positions and 700,000 grandmaster games. The endgame database contained many six piece endgames and five or fewer piece positions. Before the second match, the chess knowledge of the program was fine tuned by grandmaster Joel Benjamin. The opening library was provided by grandmasters Miguel Illescas, John Fedorowicz and Nick De Firmian. Deep Blue's programmers tailored the computer program to beat Kasparov by studying in great detail prior games Kasparov had played. When Kasparov requested that he be allowed to study other games that Deep Blue had played so as to better understand his opponent, IBM refused. However, Kasparov did study many popular PC computer games to become familiar with computer game play in general.
After losing the match, Kasparov said that he sometimes saw deep intelligence and creativity in the machine's moves, which he could not understand. He also suggested that humans may have helped the machine during the match, based on the fact that other computer programs at that time could not find some of the strong moves that Deep Blue did, particularly 37. Be4, in the second game. However, recent computer programs such as Rybka and the Computer Assistant Project did find this move. In addition, Kasparov said the program made a human-like mistake on move 44. Kf1 in the same game. However, recent programs also make the same mistake. Kasparov demanded a rematch, but IBM declined and retired Deep Blue.
In 2003 a documentary film was made that explored these claims. It was titled Game Over: Kasparov and the Machine and implied that Deep Blue's heavily promoted victory was a plot by IBM to boost its stock value. Clearly coverage in the popular press was a goal of the effort and this did not hurt the sales of IBM supercomputers.
The rules allowed the developers to modify the program between games. Deep Blue was modified between games to understand Kasparov's playstyle better, allowing it to avoid a trap in the final game that the computer had fallen for twice before.
One of the two racks that made up Deep Blue is on display at the National Museum of American History in their exhibit about the Information Age; the other rack appears at the Computer History Museum in their "Mastering The Game: A History of Computer Chess" exhibit.
[edit] Future
Feng-hsiung Hsu later claimed in his book Behind Deep Blue: Building the Computer that Defeated the World Chess Champion that he had the rights to use the Deep Blue design to build a bigger machine independently of IBM to take Kasparov's rematch offer, but Kasparov refused a rematch (see also Hsu's open letter about the rematch linked below). Kasparov's side responded that Hsu's offer was empty and more of a demand than an offer because Hsu had no sponsors, no money, no hardware, no technical team, just some patents and demands that Kasparov commit to putting his formal world title on the line before further negotiations could even begin (with no guarantees as to fair playing conditions or proper qualification matches).
Kasparov's loss to Deep Blue inspired the creation of a new game called Arimaa which is still played with a standard chess set, but which is also thought to be much more difficult for computers.
Deep Blue, with its capability of evaluating 200 million positions per second, was the strongest computer that ever faced a world chess champion. Today, in computer chess research and matches of world class players against computers, the focus has often shifted to software and creating more intelligent chess programs, rather than using brute force computing power. Modern chess programs like Rybka, Deep Fritz or Deep Junior are more advanced than the code used on Deep Blue. In a recent match, Deep Fritz vs. Vladimir Kramnik in November 2006, the program ran on a personal computer containing two Intel Core 2 Duo CPUs, capable of evaluating only 8 million positions per second, but searching to an average depth of 17 to 18 ply in the middlegame.
[edit] Deep Blue in popular culture
- Deep Blue was seen on the Futurama episode "Anthology of Interest I" as a member of Al Gore's Vice Presidential Action Rangers, a "group of top nerds whose sole duty is to prevent disruptions in the space-time continuum."
- Servotron has a song entitled "Deep Blue, Congratulations" on their album Entertainment Program for Humans (Second Variety).
- On the April 14, 2005 episode of The Daily Show with Jon Stewart, Stewart invited a fictional version of Deep Blue to comment on the recent extradition of former chess champion Bobby Fischer. Deep Blue didn't offer any analysis of any kind, and repeatedly suggested they play chess, and later offered a visit to a porn site.
- Deep Blue is a 1997 album and song by Peter Mulvey. The title song was inspired by the 1997 Kasparov match.
- Deep Blue made an appearance on The Tonight Show with Jay Leno, and was parodied on Late Night with David Letterman with Top Ten Ways Deep Blue is Celebrating its Victory.
- Referenced in the internet sensation Pure Pwnage. Said to have been beaten by Teh_Masterer, who had used only a row of pawns and a single bishop.
[edit] See also
- Blue Gene
- Computer chess
- IBM Deep Thunder
- Hydra - a modern engine with dedicated hardware
- Game Over: Kasparov and the Machine, a documentary film about Kasparov vs. Deep Blue
[edit] External links
- Deep Blue's games at chessgames.com
- Complete games from the first match with Kasparov
- Play through the Garry Kasparov vs Deep Blue 1997 games
- IBM Research pages on Deep Blue
- IBM page with the computer logs from the games
- Open letter from Feng-hsiung Hsu on the aborted rematch with Kasparov
- Deep Blue system described by Feng-hsiung Hsu, Murray Campbell and A. Joseph Hoane Jr.
