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Subject: Re: GM Christiansen's rook sac is non-forcing.

Author: John Merlino

Date: 16:27:13 10/03/02

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On October 02, 2002 at 14:43:34, John Merlino wrote:

>On October 01, 2002 at 22:39:38, Jim Monaghan wrote:
>
>>On October 01, 2002 at 21:41:34, John Merlino wrote:
>>
>>In the first position John, the Black rook sacrifice is non-forcing. White does
>>not have to take it and can instead reply 54.Qb2!? to oppose queens and possibly
>>take some wood off, and also to at least cover some dark squares which White is
>>weak on. Black looks like he definitely has the initiative with the more
>>comfortable position, but it's definitely another matter to prove that his
>>"attack" will penetrate the White position to convert his edge to the full
>>point. I played around with the resulting position with various engines and
>>could find nothing conclusive. Black seems a bit better, but that's about it.
>>This White queen move becomes important for the analyst, especially if Susan
>>Polgar believes the position is a Black win after a White acceptance of the rook
>>sac.
>>
>>[D] 8/p1p5/Pp1p2nk/1P1Bq1r1/2P1Pp1p/6r1/1Q3RPP/3R3K b - - 0 54
>>
>>Cheers,
>>Jim
>
>You are, of course, correct. Although CM never considered NOT taking the rook
>during the game. I will run the position on the P4 overnight and see what it
>comes up with.
>
>jm

I have let our P4-2.66 run on this position for 28 hours, and here is what it
came up with:

Time	Depth	Score	Positions	Moves
0:00	1/3	5.13	1146		54.hxg3 hxg3 55.Rfd2 Qe7
0:00	1/4	5.00	2484		54.hxg3 hxg3 55.Rfd2 Rh5+ 56.Kg1
					Qe7
0:00	1/5	4.64	10185		54.hxg3 hxg3 55.Rf3 Rh5+ 56.Kg1
					Qe7 57.Kf1
0:00	1/6	4.91	42212		54.hxg3 hxg3 55.Rfd2 Rh5+ 56.Kg1
					Qe7 57.Qf3 Qh4 58.Kf1 Qh1+ 59.Ke2
0:00	1/7	4.10	69679		54.hxg3 hxg3 55.Rfd2 Rh5+ 56.Kg1
					Qe7 57.Kf1 Ne5 58.Qc3 Rh1+ 59.Ke2
0:00	1/8	3.95	121016		54.hxg3 hxg3 55.Rb2 Rh5+ 56.Kg1
					Qe7 57.Kf1 Ne5 58.Qc3 Rh1+ 59.Ke2
					Rh2
0:01	1/9	1.91	517553		54.hxg3 hxg3 55.Rfd2 Rg4 56.Kg1
					Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Kd3
					Ne5+ 60.Kc2
0:02	1/10	2.17	776011		54.hxg3 hxg3 55.Rfd2 Rg4 56.Kg1
					Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Kd3
					Qf3+ 60.Kc2 Qxb3+ 61.Kxb3 f3
0:09	2/11	0.72	2735823		54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1
					Qh5 57.e5 Qh2+ 58.Kf1 Qh1+ 59.Ke2
					Qxg2+ 60.Ke1 Rg5 61.Rd2 Rxe5+ 62.Kd1
					Qh1+ 63.Kc2
0:19	3/12	0.34	5431609		54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1
					Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Ke1
					Qh2 60.e5 g2 61.Rh3+ Nh4 62.Bxg2
					Qxg2 63.exd6
1:34	4/13	0.56	26200821	54.hxg3 hxg3 55.Ra2 Rg4 56.Kg1
					Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Kd3
					Ne5+ 60.Kc3 Qf3+ 61.Kb2 g2 62.Raa1
					Qf2+ 63.Qc2 Qe3
3:25	5/14	0.63	58517496	54.hxg3 hxg3 55.Ra2 Rg4 56.Kg1
					Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Kd3
					Ne5+ 60.Kc3 Qf3+ 61.Kb4 g2 62.Rg1
					Qxb3+ 63.Kxb3 Rg3+ 64.Ka4 f3 65.Rd2
14:43	6/15	-0.28	255650469	54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1
					Rh4 57.Kf1 f3 58.Qxf3 Rf4 59.Rf2
					Rxf3 60.Rxf3 Qh5 61.Ke1 Qh1+ 62.Rf1
					Qxg2 63.e5
1:04:33	7/16	-0.42	1073493321	54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1
					Rh4 57.Kf1 f3 58.Qxf3 Rf4 59.Rf2
					Qg5 60.e5 Rxf3 61.Rxf3 Nxe5 62.Rf8
					Qe3 63.Be6
5:38:26	8/17	-0.11	1473843047	54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1
					Qh5 57.e5 Nxe5 58.Qc3 Qh2+ 59.Kf1
					Qh1+ 60.Ke2 Qxg2+ 61.Ke1 Qh2 62.Rd2
					Qh4 63.Rg2 Nxf3+ 64.Qxf3 Rg7 65.Be4
					Qh1+ 66.Ke2
12:33:56 9/18	-0.45	103126968	54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1
					Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1
					Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Rxe5 62.Kd4
					Ne7 63.Be4 Qe2 64.Rh1+ Kg5 65.Rxg3+
					fxg3 66.Qxg3+ Kf6 67.Rh6+ Kf7 68.Bg6+
					Nxg6 69.Qxg6+

However, after 54.Qb2, as you suggest, a relatively short search says this:

Time	Depth	Score	Positions	Moves
0:00	1/3	0.43	993		54...Qxb2 55.Rxb2 Ra3 56.Rf2
0:00	1/4	0.49	2511		54...Qxb2 55.Rxb2 Re3 56.Rf2 Kg7
0:00	1/4	0.48	4250		54...Re3 55.Qxe5 Rxe5 56.Rfd2 Re8
0:00	1/5	0.54	9449		54...Re3 55.Qxe5 dxe5 56.Rfd2 Ne7
0:00	1/5	-0.06	11852		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 Rxh3
0:00	1/6	-0.07	21344		54...Qxb2 55.Rxb2 Re3 56.Rbd2 Ne5
					57.Rf1 h3
0:00	1/7	-0.05	61674		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 Rxh3 58.Be6 Re3 59.Bf5
0:00	1/8	-0.05	105112		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 Rxh3 58.Be6 Re3 59.Bf5
0:01	1/9	-0.25	236443		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 f3 58.Rfd2 Re2 59.Rxe2 fxe2
0:02	1/10	-0.26	525935		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 f3 58.Be6 Rxe4 59.Bd5 Rf4
					60.Bxf3 Rxc4
0:05	2/11	-0.54	1378737		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 f3 58.h4 Nxh4 59.Rdf1 Re2
					60.Rxe2 fxe2
0:16	3/12	-0.55	4581082		54...Qxb2 55.Rxb2 Re3 56.Rf2 h3
					57.gxh3 f3 58.Be6 Ne5 59.h4 Rg7
					60.Bf5 Re2 61.Rxe2 fxe2
0:46	4/13	-0.67	13427568	54...Qxb2 55.Rxb2 Re3 56.Rbd2 Ne5
					57.Rc2 h3 58.gxh3 Rxh3 59.Be6 Re3
					60.Bf5 Rg7 61.Rf2 f3
3:00	5/14	-0.82	53118189	54...Qxb2 55.Rxb2 Re3 56.Rf1 h3
					57.gxh3 f3 58.Rbf2 Ne5 59.h4 Rh5
					60.Kg1 Rxh4 61.Rd2 Rg4+ 62.Kf2 Rb3
9:19	6/15	-0.91	172459458	54...Qxb2 55.Rxb2 Re3 56.Rf1 h3
					57.gxh3 f3 58.Rbf2 Ne5 59.Be6 Rxe4
					60.Bd5 Rf4 61.Bxf3 Rgf5 62.Kg2 Rxc4
39:33	7/16	-0.84	732706828	54...Qxb2 55.Rxb2 Rc3 56.Rf2 h3
					57.gxh3 f3 58.Be6 Ne5 59.Re1 Nxc4
					60.Bxc4 Rxc4 61.Rxf3 Rxb5 62.Rf8
					Rbc5 63.Rg1 Rg5 64.Rh8+ Kg6 65.Rxg5+
					Kxg5

jm



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