Deep Blue (chess computer)

Deep Blue was a chess computer developed by IBM.

Deep Blue succeeded in 1996 as the first computer, the reigning world chess champion ( Garry Kasparov ) in a game with regular time controls to beat. Won the 1997 Deep Blue against Kasparov an entire race from six games under tournament conditions.


Inventor of the project was Feng -hsiung Hsu. He started it in 1985 with the development of an integrated on a chip Zuggenerators as chip testing at Carnegie Mellon University and gave the finished system named Deep Thought, after the same computer in the novel The Hitchhiker's Guide to the Galaxy by Douglas Adams. In 1989, Hsu at the team of IBM and conducted research with Murray Campbell on problems of parallel calculation. From this work, Deep Blue was born. This name was derived from the American nickname for the U.S. giant IBM, which was named because of its large market capitalization and its blue logo "Big Blue".

The system derived its playing strength mainly from its enormous computing power. Deep Blue was a massively parallel, SP -based RS/6000-Rechner. The 1996 version consisted of 36 nodes and 216 special VLSI chess processors, the version 1997 of 30 knots with 480 chips. Each node had 1GB of RAM and 4 GB of disk space. The chess software was written in C and ran under the AIX operating system 4.2. They calculated depending on the type of position between 100 and 200 million on average 126 million positions per second.

Its evaluation function consisted of running in hardware extensive parameter evaluation and executed in software weighting of these parameters (eg: the importance of the safety of the king is in comparison with a space advantage in the center ). The optimal values ​​of the parameters were determined by the system itself, by analyzing thousands of master games. Before the second match, the chess knowledge of the program by grandmaster Joel Benjamin has been optimized. The opening book came from the grandmasters Miguel Illescas Cordoba, John Fedorowicz, and Nick de Firmian.

The matches against Kasparov

Kasparov won the first match, which was held in Philadelphia in February 1996, for itself. He won three games, made two draws and lost a game, so he hit Deep Blue 4:2. The first game of the match, Deep Blue - Kasparov, Philadelphia 1996 1st competition game, became famous. The competition was about a prize fund of U.S. $ 500,000 and was broadcast live on the Internet.

Then upgraded IBM from his machine with stronger hardware and joined in May 1997 again against Kasparov. Deep Blue, which now could calculate 200 million positions per second, won the rematch 3,5:2,5. Thus, the system was also the first computer that was able to win a contest in " tournament conditions " against a reigning world chess champion for itself.

After Kasparov had won the first match game, it came in the second game to a remarkable final game: Kasparov gave in on drawn position. In the diagram position, he estimated that he had to replace the ladies and his position after 45 ... Db6xc6 46 d5xc6 would be hopeless. However, it turned out that he ... Qb6 -e3 - e8 46 Dc6xd6 Rb8 a draw by perpetual check could have achieved by 45. Kasparov had this option is not taken into account because he did not think it possible that the computer could overlook such a tactical way. After this avoidable defeat Kasparov was posted mentally.

In the sixth and final game Kasparov broke with a completely black and had to take one of the shortest defeats of his career:

1 e2- e4 c7 - c6 2 d2 -d4 d7 -d5 3 Nb1 - c3 d5xe4 4 Sc3xe4 Sb8 - d7 5 Ne4 - g5 - f6 Ng8 6 Lf1 -d3 e7 - e6 7 f3 Sg1 - h7 h6 - 8 Sg5xe6 Qd8 - e7 9 0-0 10 Bd3 - g6 f7xe6 Ke8 -d8 11 f4 b7 - b5 Lc1 - 12 a2 -a4 - b7 Bc8 13 Tf1 - e1 Nf6 -d5 14 Lf4 - g3 Kd8 - c8 15 a4xb5 c6xb5 16 Dd1 -d3 Bb7 - c6 - 17 lg6 f5 e6xf5 18 Te1xe7 Lf8xe7 19 c2 - c4 1-0

After the game was discussed whether there had been at the 7 train from black to a finger mistake, because 7 by the train ... Bf8 - d6 Kasparov would avoid tactical complications and achieve a solid position. After the piece sacrifice of white that the computer had stored in its opening book and à tempo played, Kasparov seemed surprised. Joel Benjamin suggested, however, that it was acting in his reactions, because shortly before the variant came in a lot of Gennady Timoščenko action against the chess program Fritz, who was Kasparov probably known. In the 11th train Kasparov made ​​the partie -critical error, that would be better ... Nf6 -d5 been played by Timoščenko 11 with an unclear position. Perhaps Kasparov trusted that Deep Blue would play similar to Fritz, but this was not the case.

2003 brought about the match a documentary by Vikram Jayanti, entitled Game Over: Kasparov and the Machine.

Discussion about the fairness of the competition

The team at Deep Blue had a complete history of all public games Kasparov; whose analyzes have been incorporated into the programming. Conversely, hardware and programming of Deep Blue over the first contest in the previous year had been massively improved; Kasparov was thus de facto an unknown adversary.

The rules also gave the programmers the ability to modify the program between games, which they did extensively. The code has been released and changed during the event of errors, which Kasparov ultimately not only played against the machine, but also against the Deep Blue team, as this helped his system. In fact, Kasparov played after every code change against a different opponent.

Hsu met this objection by pointing out that a human opponent learns from already played games and even made ​​mistakes in other games as far as possible avoids; however, corresponds to a manual modification to the code neither machine learning in the sense of artificial intelligence nor the natural learning of man. Even IBM itself contradicts Hsu's argument, and agrees with Kasparov that Deep Blue was not a learning system, as the company indicates on its website of the Deep Blue project:

"Deep Blue, as it stands today, is not a ' learning System. ' It is not THEREFORE Capable of Utilizing artificial intelligence to learn from its opponent Either or 'think ' about the current position of the chess board. "


"Any changes in the way Deep Blue plays chess must be Performed by the members of the development team in between games. Garry Kasparov can alter the way he plays at any time before, falling on, and / or after each game. "

After the lost match Kasparov said to have observed, in many features of the machine high (human ) intelligence and creativity and guessed the machine had been helped during the game of people. Kasparov demanded revenge, but IBM refused to allow the world champion, among other things because of the allegations, a rematch and dismantled Deep Blue in its individual parts. The project cost a total of about IBM 5 million U.S. dollars. Parts of Deep Blue are now in the Smithsonian Institution in Washington, DC and to see the Computer History Museum in Silicon Valley.

The refused Rematch

In his book Behind Deep Blue: Building the Computer did Defeated the World Chess Champion (2002, ISBN 0-691-09065-3 ) claims Feng -hsiung Hsu, he had acquired the rights to the chess chips created by him from IBM to at need to build an even stronger engine and accept this Kasparov Rematch offer, but Kasparov now refuse to a rematch.