Author: James Robertson
Date: 20:25:37 11/20/98
Go up one level in this thread
On November 20, 1998 at 10:53:03, Ernst A. Heinz wrote: >On November 18, 1998 at 05:00:14, Ernst A. Heinz wrote: >> >>On November 17, 1998 at 06:36:49, Ernst A. Heinz wrote: >> >>>On November 16, 1998 at 18:19:53, Amir Ban wrote: >>> >>>>On November 16, 1998 at 14:50:57, Bruce Moreland wrote: >>>> >>>>>r1r1q1k1/6p1/p2b1p1p/1p1PpP2/PPp5/2P4P/R1B2QP1/R5K1 w - - 0 1 >>>>> >>>>>It has been contended that this move would be difficult for a computer to find, >>>>>and this has caused some doubts to be raised as to whether the computer found it >>>>>without assistance in this game. >>>>> >>>>>I would like to ask how we can clear this up absent input from DB. >>>>> >>>>>Has anybody run this for a long period on a micro, and if so, was any move >>>>>selected other than 35. Qb6? >>>>> >>>>>Is the counter-attacking line 35. Qb6 Qe7 36. axb5 Rab8 37. Qxa6 e4 supposedly >>>>>the reason that white shouldn't play 35. Qb6? Or is it some other line? If it >>>>>is too hard or impossible to find 35. axb5, would finding this line show >>>>>anything? >>>>> >>>>>Is there some minimum score delta we can achieve between the position after 35. >>>>>axb5 and 35. Qb6 that might be evidence that DB should be given the benefit of >>>>>the doubt? >>>>> >>>>>Are these questions unfair or wrong, if so, are their other questions that can >>>>>be asked and possibly answered that will help clear this up? >>>>> >>>>>bruce >>>> >>>> >>>>This is move 36 but the other details are correct. >>>> >>>>The first time this was discussed on CCC, Chris Whittington was still here, and >>>>he reported for CSTal. It was closer than others, but still couldn't bridge the >>>>gap. >>> >>>I fed this position into the current "DarkThought" yesterday and it liked Qb6 >>>with a score of roughly +1.7 up to iteration #18 inclusively. Then, it failed >>>low on Qb6 (score <= 1.39) in iteration #19 after processing 6,490,725,565 >>>nodes. Currently, it is still engaged in resolving the fail-low (see below). >>> >>>//////////////////////////////////////////////////////////////////////////////// >>> >>>r1r1q1k1/6p1/p2b1p1p/1p1PpP2/PPp5/2P4P/R1B2QP1/R5K1 w - - 0 1 >>> >>># Clearing chess engine. >>># Engine sleeps. >>>- - >>> +------------------------+ >>>8 |*R :::*R :::*Q :::*K :::| >>>7 |::: ::: ::: *P: | >>>6 |*P ::: *B: *P: *P:| >>>5 |:::*P ::: P *P: P ::: | >>>4 | P :P:*P ::: ::: :::| >>>3 |::: :P: ::: ::: P | >>>2 | R ::: B ::: :Q: P :::| >>>1 |:R: ::: ::: :K: | >>> +------------------------+ >>> a b c d e f g h >>> >>>14.01 Qb6 Rd8 Be4 Rac8 Qxa6 bxa4 Qxa4 Qxa4 Rxa4 Rd7 ... (1.71) #62711053 >>>15.01 Qb6 Rd8 Be4 Rac8 Qxa6 bxa4 Qxa4 Qh5 Kh2 Qg5 ... (1.69) #140398448 >>>16.01 Qb6 Rd8 Be4 Rac8 Qxa6 bxa4 Qxa4 Qh5 Qa7 ... (1.70) #423411650 >>>17.01 Qb6 Rd8 Be4 Rac8 Qxa6 bxa4 Qxa4 Qh5 Qa7 Qh4 ... (1.73) #1230726361 >>>18.01 Qb6 Rd8 Be4 a5 axb5 axb4 Rxa8 Rxa8 Rxa8 Qxa8 ... (1.64) #3337837066 >>>19.01 Qb6 <=178? (1.39) #6490725565 >>> >>>//////////////////////////////////////////////////////////////////////////////// >> >>I run this on a 500MHz Alpha-21164a and the fail-low of iteration #19 got >>resolved to +1.26 after 14:34 hours and 11,196,023,081 nodes (see below). >> >>>19.01? Qb6 Rd8 Be4 a5 axb5 axb4 Rxa8 Rxa8 Rxa8 Qxa8 ... (1.26) #11196023081 >> >>I will let "DarkThought" continue the calculation as long as the other people >>at our institute do not get too angry at me for blocking so many Alphas ... :-) > >"DarkThought" has just finished iteration #20 after 70 hours of computation. >36. Qb6 remained the best move and the PV took nearly 52 hours and exactly >39,839,971,433 nodes to resolve. The expected best reply changed to 36.. Qf8 >and the score crept up again to +1.36. Deep blue was searching 250,000,000 nps right? Would it take roughly 160 seconds (40,000,000,000 / 250,000,000) for Deep Blue to search the same number of nodes? James > >20.01 Qb6 Qf8 axb5 Rcb8 Qa5 Qe7 Be4 Qa7+ b6 Rxb6 ... (1.36) #39839971433 > >=Ernst=
This page took 0.03 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.