Author: Roy Eassa
Date: 11:34:27 11/30/01
Go up one level in this thread
On November 30, 2001 at 13:34:19, ALI MIRAFZALI wrote: >The following Position is Taken from a Game Played by IGM Yuri Shulman >in a recent tournament in the USA: >[D] r1b2r2/pp1nqn1k/2pp2pb/4Pp1p/2PP1p1N/2N3BP/PPQ1B1P1/3RR1K1 w - 1 0 >In this position Amazingly 19.Nxg6!!! Wins by Force .However Fritz 6 does not >find this move however Chessmaster 8000 does! However there is a slight problem >Here is the line given by Chessmaster 8000 when run after about 3.5 minutes. >Time:3:32 Depth 10 Score:0.09 Positions :13062068 >Line:19.Nxg6 Kxg6 20.Qxf5+ Kg7 21.Bd3 Rh8 22.Qg6+ Kf8 23.exd6 Qg5 24.Qxg5 Bxg5 >25.Bh2 > >The Problem Here is that Chessmaster 8000 changes its mind at higher plys! >to the inferior 19.exd6. Here is the Analysis >Time:40:02 Depth 12 Score:0.00 Positions :149376486 >Line:19.exd6 Qxd6 20.c5 Qf6 21.Bf2 Ng5 22.Nf3 b5 23.d5 Nxf3+ 24.gxf3 a6 >25.dxc6 Qxc6. > >Now we come to the Most intertesting part of this article;that is why 19.Nxg6 >wins.In the actual game there was 19.Nxg6 Kxg6 20.Qxf5+ Kg7 21.Bd3 Rh8 22.Qg6+ >Kf8 .and now 23.e6!! instead of 23.exd6 as given by Chessmaster 8000. >So Therefore one has to feed 23.e6!! in the line starting with >19.Nxg6 to see that 19.Nxg6 actually wins. This is confirmed by chessmaster >8000 as follows: >Time:10:54 Depth 11 Score:1.17 Positions : 43387513 > Line:23.e6 fxg3 24.exf7 Be3+ 25.Kh1 Ne5 26.dxe5 Qxe5 27.Ne4 Bf5 28.Qxd6+ Qxd6 >29.Nxd6 Bg4 >In this line if Black tries 24... Qxf7 he will be crushed by 25.Qd6+ Kg8 >26.Re6! Ne5 27.Rf6 Qd7 28.Qxe5 Bg7 29.Rdf1 Rh6 (with a 3 pawn advatage to white >according to CM 8000).So 19.Nxg6!!! is actually winning. >In the actual game Black blundered with 23...Rg8? and lost after 24.Bh4 Rxg6 >25.Bxe7+ Kxe7 26.exd7+ Re6 27.dxc8=Q 1-0 >No program other than CM8000 even comes close to suggesting 19.Nxg6!!! .And >even CM8000 changes its mind and does not see the winning lines. >It is My opinion that this position should serve as a BENCHMARK for the >progress of future programs/Computers.It is only when a program can clearly >see why 19.Nxg6!!! wins can one write chess as pratically solved by Computers. >I am howeverinterssted in results by other programs.(at this point I donot >think anyprogram will see this:but I am still curious). Gambit Tiger 2.0 Aggressive, on a 1.2 GHz Athlon, cannot find the whole line up front in any reasonable timeframe. Even when the first six ply are pre-played, it takes it 13 (more) ply to switch to Qg6+ as the preferred move, 14 ply to give it a positive score (+0.56), and, after 15 ply, only sees it as +0.68: 00:00:00.0 -1.06 8 154870 exd6 Qg5 Bh2 Nxd6 Qe6 Qf6 d5 Qxe6 Rxe6 00:00:00.0 -1.06 8 179340 exd6 Qg5 Bh2 Nxd6 Qe6 Qf6 d5 00:00:00.1 -0.16 8 282065 Bh4 00:00:00.1 0.72 8 309092 Bh4 Ndxe5 Bxe7 Bxf5 dxe5 Bxd3 Bf6+ Kf8 Bxh8 Bxc4 00:00:01.1 -0.14 9 402244 Bh4 Qxh4 e6 Qe7 exd7 Qxd7 Qxh5 f3 Qg6+ Kf8 Ne4 fxg2 00:00:02.3 -0.12 10 732278 Bh4 Qxh4 e6 Qe7 exd7 Qxd7 Qxh5 f3 Qg6+ Kf8 Ne4 00:00:04.7 -0.32 11 1735058 Bh4 Qxh4 e6 Qe7 exd7 Qxd7 Qg6+ Kf8 Qxh5 Rg8 Bg6 00:00:15.2 0.58 12 5559858 Bh4 00:00:18.6 0.62 12 6663902 Bh4 Qxh4 e6 Qf6 exd7 Bxd7 Qxd7 f3 Re6 Rad8 Rxf6 Be3+ Kh2 Rxd7 Rxf3 Bxd4 00:01:43.8 -0.56 13 38346234 Bh4 Qxh4 e6 Qe7 Qg6+ Kf8 exf7 Qxf7 Qxd6+ Kg8 Re6 Bf8 Rg6+ Bg7 Rf1 f3 Rxf3 00:02:17.7 -0.34 13 50159464 Qg6+ Kf8 e6 fxg3 exf7 Qxf7 Qxd6+ Kg8 Qxg3+ Qg7 Qd6 Nf8 Re7 Qg5 Qd8 Be6 Qxa8 Qxe7 00:03:03.4 0.56 14 66799415 Qg6+ 00:03:59.4 0.56 15 87109588 Qg6+ 00:06:13.7 0.68 15 133502317 Qg6+ Kf8 e6 fxg3 exf7 Qxf7 Qxd6+ Kg8 Qxg3+ Qg7 Qd6 Qf7 Re6 Bf8 Rg6+ Bg7 Qc7 Rh6
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