Author: Roy Eassa
Date: 12:04:38 11/30/01
Go up one level in this thread
On November 30, 2001 at 14:34:27, Roy Eassa wrote:
>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
Analysis with help from Gambit 2:
1. Nxg6!! Kxg6 2.Qxf5+ Kxf5
(2...Kg7 3.Bd3 Rh8 4.Qg6+ Kf8 5.e6! fxg3 6.exf7 Ne5
(6...Be3+ 7.Kh1 Qg5
(7...Ne5 8.dxe5 Qxe5 9.Bb1 wins)
8.Qe6 Bf2
(8...Nf6 9.Qxe3 Qxe3 10.Rxe3 h4 11.Rf1 Rh6 12.Ref3 should win)
9.Qxd6+ Kg7 10.Re8 wins)
(6...Qxf7 7.Qxd6+ Kg8 8.Re6! Nf8 9.Rxh6 Rxh6 10.Qxh6 Qg7 11.Qxh5 Qxd4+
12.Kh1 wins)
7.dxe5 dxe5 8.Bb1 Bg7 9.Ne4 Rh6 10.Qxg3 Be6 11.Rf1 Bxc4 12.Rf2 h4 13.Qc3 Bd5
14.Rdf1 should win)
3.Bd3+ Kg5 4.Bxf4+ Kxf4 5.Re4+ Kf5 6.Rg4+ Ke6 7.d5+ cxd5 8.cxd5+ Kxe5 9.Re1+
Be3+ 10.Rxe3+ Kf6 11.Rg6#
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