Did deep blue cheat?

[ethanara]

I have seen the movie game over kasparov , and in game 2, you may know that deep blue did a "noncomputer" move
Gary then accused them for cheating.
but what if we make a modern chess engine do the position, and see what happens?
I know this wouldnt prove anything , but it will be fun to see

[Mark Mason]

Hi Ethan,

The game you are referring to is Game 2 of the 1997 rematch Deep Blue vs. Kasparov.

In this game Kasparov accused IBM of cheating, a claim repeated in the documentary Game Over: Kasparov and the Machine. The critical move that he claimed was a "human move" was 37.Be4. Kasparov eventually resigned, although post-game analysis indicates that the game could have been drawn. The game started with the Ruy Lopez opening Smyslov Defence variation. This game was played on May 4, 1997.

1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 d6 8.c3 O-O 9.h3 h6 10.d4 Re8 11.Nbd2 Bf8 12.Nf1 Bd7 13.Ng3 Na5 14.Bc2 c5 15.b3 Nc6 16.d5 Ne7 17.Be3 Ng6 18.Qd2 Nh7 19.a4 Nh4 20.Nxh4 Qxh4 21.Qe2 Qd8 22.b4 Qc7 23.Rec1 c4 24.Ra3 Rec8 25.Rca1 Qd8 26.f4 Nf6 27.fxe5 dxe5 28.Qf1 Ne8 29.Qf2 Nd6 30.Bb6 Qe8 31.R3a2 Be7 32.Bc5 Bf8 33.Nf5 Bxf5 34.exf5 f6 35.Bxd6 Bxd6 36.axb5 axb5 37.Be4 Rxa2 38.Qxa2 Qd7 39.Qa7 Rc7 40.Qb6 Rb7 41.Ra8+ Kf7 42.Qa6 Qc7 43.Qc6 Qb6+ 44.Kf1 Rb8 45.Ra6 1-0

At the time it was reported that Kasparov missed the fact that after 45... Qe3 46.Qxd6 Re8, Black can force a draw by perpetual check. His friends told him so the next morning. They suggested 47.h4 h5!, to result in a quick ending. However, it was discovered in 2007 by Internet analysis that after 45... Qe3 46. Qxd6 Re8 47. Qd7+ Re7 48. Qc6 Qxe4 49. d6 Qd3+ 50. Kg1 Re8 51. Ra1 there is no perpetual check and the attack continues.

It was believed that the game became subject to a forced draw instead of a probable win for Deep Blue when it moved 44.Kf1 instead of an alternate move of its king. Regarding the end of game 2 and 44.Kf1 in particular, chess journalist Mig Greengard in the Game Over film states, "It turns out, that the position in, here at the end is actually a draw, and that, one of Deep Blue's final moves was a terrible error, because Deep Blue has two choices here. It can move its king here or move its king over here. It picked the wrong place to step." Another in that film, four-time US champion Yasser Seirawan, then concludes that, "The computer had left its king a little un-defended. And Garry could have threatened a perpetual check, not a win but a perpetual check."

Kasparov...."I didn't play the opening very well - I was passive, because I thought the computer would not be able to understand and handle well the resulting position. I wish I would have played otherwise, however, in order to play 'normal' openings you have to spend a couple of months checking your openings with your computer. Every line. Because one mistake in the Najdorf Sicilian could be fatal. The level of preparation would be different. Obviously Deep Blue had a large team behind it studying the openings.

The rest of the game is history. Including my resignation in a drawn position. The truth is that I was very tired and couldn't believe the way the machine had just played. I trusted its calculations. I assumed that if the machine allowed a move such as Qe3 at the end, it had calculated everything that could follow and found wins, so I didn't even bother checking it. Costly error, as I soon found out." - Kasparov

[pocopito]

Fruit running on a single core in my laptop is able to find it in a couple of minutes (are engines becoming more huma alike?)

1 +0.39 1.Rxa8 Rxa8 2.Rxa8 Qxa8 (0.00)
1 +0.49 1.Kh1 (0.00)
1 +0.52 1.Ra3 (0.00)
1 +0.62 1.Ra5 (0.00)
1 +0.97 1.Ra7 Rxa7 2.Rxa7 (0.00)
2 +0.97 1.Ra7 Rxa7 2.Rxa7 (0.00)
3 +0.59 1.Ra7 Rxa7 2.Rxa7 e4 (0.00)
4 +0.52 1.Ra7 Rxa7 2.Rxa7 Ra8 3.Be4 Rxa7 4.Qxa7 (0.00)
4 +0.86 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe3 (0.00)
5 +1.11 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kh7 4.Ra7 (0.00)
6 +1.05 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kh7 4.Ra7 Qf8 (0.00)
7 +0.91 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Rb8 5.Ra7 (0.01)
8 +1.07 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Ra6 Rd8 5.Ra7 Rd7 (0.01)
9 +0.96 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Rb8 5.Ra7 Qd8 6.Qc6 (0.02)
10 +1.06 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Ra8 5.Qxe8+ Rxe8 6.Ra7 Re7 7.Rb7 e4 8.Rxb5 (0.04)
11 +1.10 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Rb8 5.Ra6 Rd8 6.Ra7 Qd7 7.Kg1 (0.07)
12 +0.63 1.Qb6 Rxa2 2.Rxa2 Ra8 3.Ra5 Rxa5 4.bxa5 Qb8 5.Qxb8+ Bxb8 6.a6 Ba7+ 7.Kf1 Bc5 8.Ke2 Kf7 9.Kf3 (0.18)
12 +0.72 1.Be4 Rcb8 2.Kh2 Rxa2 3.Qxa2 Kh7 4.Qa7 Qc8 5.g4 Rb7 6.Qa6 Qd7 7.Qc6 (2.35)
13 +0.67 1.Be4 Rcb8 2.Kh2 Rxa2 3.Qxa2 Bc7 4.g4 Bb6 5.d6 Qd7 6.Rd1 Rd8 7.Qe2 Kh7 (3.56)
14 +0.67 1.Be4 Rcb8 2.Kh2 Rxa2 3.Qxa2 Bc7 4.Qa6 Bb6 5.d6 Qd7 6.Rd1 Kh7 7.g3 Be3 8.Ra1 (6.95)
15 +0.69 1.Be4 Rcb8 2.Kh2 Rxa2 3.Qxa2 Bc7 4.Qd2 Bd6 5.Ra6 Qd8 6.Qf2 Rb7 7.Ra1 Kh7 8.g4 Rd7 (11.70)
15 +1.13 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Rb8 5.Ra6 Rd8 6.Ra7 Bd6 7.Kf2 Be7 8.Bd1 Qf7 9.Qxf7+ Kxf7 10.Bh5+ Kf8 (12.00)
16 +1.14 1.Qb6 Rxa2 2.Rxa2 Bc7 3.Qe6+ Kf8 4.Kf1 Rb8 5.Ra6 Rd8 6.Ra7 Bd6 7.Kf2 Be7 8.Bd1 Qf7 9.Qxf7+ Kxf7 10.Bh5+ Kf8 11.Bf3 (13.10)
17 +0.61 1.Qb6 Rxa2 2.Rxa2 Ra8 3.Ra5 Rxa5 4.bxa5 Qb8 5.Qxb8+ Bxb8 6.Kf2 Kf7 7.a6 Ke7 8.Kf3 Ba7 9.Ke4 Kd6 10.Bd1 Bc5 11.Be2 (30.15)
17 +0.70 1.Be4 Rcb8 2.Kh2 Rxa2 3.Qxa2 Bc7 4.Qd2 Qf8 5.Ra6 Rd8 6.Qe3 Rd6 7.Rc6 Rxc6 8.dxc6 Qd6 9.g4 Qd1 10.Kg3 (48.20)
18 +0.74 1.Be4 Rcb8 2.Ra7 Kh7 3.Kh2 Rxa7 4.Qxa7 Qd8 5.Ra6 Bc7 6.g3 Rb6 7.Ra2 Qd7 8.g4 Rb8 9.Ra1 Re8 10.Qe3 (124.24)

[Leto]

If I remember right years ago I found that Rybka 2.3.2 or Rybka 3 finds 37.Be4 in a second or so.

[bob]

I have seen the movie game over kasparov , and in game 2, you may know that deep blue did a "noncomputer" move
Gary then accused them for cheating.
but what if we make a modern chess engine do the position, and see what happens?
I know this wouldnt prove anything , but it will be fun to see

Already been done, and more than one computer has produced the same move as DB...

[S.Taylor]

It would be exciting to discover that deep blue was also an ippolit derivative!

[Zagalo]

It would be exciting to discover that deep blue was also an ippolit derivative!

Actually it was based on fruit and crafty