Is this positions drawn ??

[smirobth]

I would like to see the exact rules given to Freezer and the exact analysis provided in return.

Rule1: If White's queen is captured = draw
Rule2: If White's pawn promotes = white win
Rule3: If Black's king leaves the 8 squares f8,g8,h8,f7,g7,h7,g6,h6 = white win
Rule4: If Black's rook leaves the squares b6, c6, f6, f2, h6 = white win
Rule5: If Black's pawns leave the squares g7, h6, g5 = white win
Rule6: If White's pawn advances = white win
Rule7: If Black's pawn promotes = white win
Rule8: If Black's rook is captured = white win unless the capturing piece can be recaptured = draw
Rule9: If a Black pawn is captured = white win unless the capturing piece can be captured = draw
Note that the vast majority of the rules favor White.

The output from position
[D] 3Q4/6pk/5r1p/4K2P/8/8/8/8

WTM all moves = draw
BTM Rf6-c6 or Rf6-f2 draw, all other moves lose.

All 3-4-5 tablebases present. Only some 6-man present.
All tablebases were checked to not be corrupted using Wilhelm, but only in the distant past, not immediately prior to running Freezer.

QED? I hope so, this is much further than I ever intended to go with such a trivial position.

It's ludicrous, to have to go to such measures to appease a few skeptics.

Robin, you are a far more patient man than I.

Terry

Hi Terry,
I'm not really interested in this position for the chess, which is as you and others have pointed out quite trivial. However as a philosophical matter it is interesting to me to see what people will and will not accept as proof.

[Terry McCracken]

I would like to see the exact rules given to Freezer and the exact analysis provided in return.

Rule1: If White's queen is captured = draw
Rule2: If White's pawn promotes = white win
Rule3: If Black's king leaves the 8 squares f8,g8,h8,f7,g7,h7,g6,h6 = white win
Rule4: If Black's rook leaves the squares b6, c6, f6, f2, h6 = white win
Rule5: If Black's pawns leave the squares g7, h6, g5 = white win
Rule6: If White's pawn advances = white win
Rule7: If Black's pawn promotes = white win
Rule8: If Black's rook is captured = white win unless the capturing piece can be recaptured = draw
Rule9: If a Black pawn is captured = white win unless the capturing piece can be captured = draw
Note that the vast majority of the rules favor White.

The output from position
[D] 3Q4/6pk/5r1p/4K2P/8/8/8/8

WTM all moves = draw
BTM Rf6-c6 or Rf6-f2 draw, all other moves lose.

All 3-4-5 tablebases present. Only some 6-man present.
All tablebases were checked to not be corrupted using Wilhelm, but only in the distant past, not immediately prior to running Freezer.

QED? I hope so, this is much further than I ever intended to go with such a trivial position.

It's ludicrous, to have to go to such measures to appease a few skeptics.

Robin, you are a far more patient man than I.

Terry

Hi Terry,
I'm not really interested in this position for the chess, which is as you and others have pointed out quite trivial. However as a philosophical matter it is interesting to me to see what people will and will not accept as proof.

Indeed!

[Uri Blass]

I would like to see the exact rules given to Freezer and the exact analysis provided in return.

Rule1: If White's queen is captured = draw
Rule2: If White's pawn promotes = white win
Rule3: If Black's king leaves the 8 squares f8,g8,h8,f7,g7,h7,g6,h6 = white win
Rule4: If Black's rook leaves the squares b6, c6, f6, f2, h6 = white win
Rule5: If Black's pawns leave the squares g7, h6, g5 = white win
Rule6: If White's pawn advances = white win
Rule7: If Black's pawn promotes = white win
Rule8: If Black's rook is captured = white win unless the capturing piece can be recaptured = draw
Rule9: If a Black pawn is captured = white win unless the capturing piece can be captured = draw
Note that the vast majority of the rules favor White.

The output from position
[D] 3Q4/6pk/5r1p/4K2P/8/8/8/8

WTM all moves = draw
BTM Rf6-c6 or Rf6-f2 draw, all other moves lose.

All 3-4-5 tablebases present. Only some 6-man present.
All tablebases were checked to not be corrupted using Wilhelm, but only in the distant past, not immediately prior to running Freezer.

QED? I hope so, this is much further than I ever intended to go with such a trivial position.

Yes
Getting a draw based on these rule is a proof that white does not win.

A proof that black does not win is simply the fact that QxR as first move is forcing a 6 piece tablebase draw.

Uri

[glorfindel]

Robin, you improvised and even removed the Black h6 pawn and EGTBs returned a draw. What , more proof do Dan and Uri need??

I agree with Dann that this is the least convincing proof I have read in this thread. The proposal "remove the h6 pawn, and it is still a draw" is useless, because from the first moment Uri asked for proof that Black cannot be placed in zugzwang. It is well known that in such Q v R endings, two protected squares is all the Rook needs in order to defend successfully. If you remove the h6 pawn, you immediately give the black rook a second protected square for free.

I would like to add that I find Robin's proof to be convincing. But if the h6 pawn was missing, the position becomes simpler to evaluate as a draw and his proof would be shorter. He would not have had to prove that the black Rook will always have an available square other than f6. The proof would be something like "Rf6-h6-f6-h6-f6-h6".

Finally would like to bring in the opinion of a expert on this position, namely Mark Dvoretsky. In the book "Dvoretsky's Endgame Manual", Chapter "Queen vs. Rook", paragraph "A Fortress with Multiple Pawns", he analyzes the following position

V. Khenkin, 1962
[d]8/4K2k/4Q1p1/5r1p/7P/8/8/8 b - - 0 1

1... Kh8!? (1... Kg7 and 1... Rf1 are also good) 2. Qxg6 Rf7+ 3.Ke6 Re7+ with a draw by stalemate or perpetual check.

With a shift up, the position is still drawn. But when shifted down, it is lost: White wins by means of a queen attack along the last rank.

So Dvoretsky says our position is drawn, because if we shift Khenkin's position up, we get the structure of the game Topalov-Mamedyarov.

[Terry McCracken]

Robin, you improvised and even removed the Black h6 pawn and EGTBs returned a draw. What , more proof do Dan and Uri need??

I agree with Dann that this is the least convincing proof I have read in this thread. The proposal "remove the h6 pawn, and it is still a draw" is useless, because from the first moment Uri asked for proof that Black cannot be placed in zugzwang. It is well known that in such Q v R endings, two protected squares is all the Rook needs in order to defend successfully. If you remove the h6 pawn, you immediately give the black rook a second protected square for free.

I would like to add that I find Robin's proof to be convincing. But if the h6 pawn was missing, the position becomes simpler to evaluate as a draw and his proof would be shorter. He would not have had to prove that the black Rook will always have an available square other than f6. The proof would be something like "Rf6-h6-f6-h6-f6-h6".

Finally would like to bring in the opinion of a expert on this position, namely Mark Dvoretsky. In the book "Dvoretsky's Endgame Manual", Chapter "Queen vs. Rook", paragraph "A Fortress with Multiple Pawns", he analyzes the following position

V. Khenkin, 1962
[d]8/4K2k/4Q1p1/5r1p/7P/8/8/8 b - - 0 1

1... Kh8!? (1... Kg7 and 1... Rf1 are also good) 2. Qxg6 Rf7+ 3.Ke6 Re7+ with a draw by stalemate or perpetual check.

With a shift up, the position is still drawn. But when shifted down, it is lost: White wins by means of a queen attack along the last rank.

So Dvoretsky says our position is drawn, because if we shift Khenkin's position up, we get the structure of the game Topalov-Mamedyarov.

Thanks for your insult. Removing the h6 pawn changes nothing, except one more redundant protected square.

Why have so many made a mountain out of a molehill???

Will anyone contest you?

[Dann Corbit]

I was going to remove myself from this debate, but after such an insult, it's not so easy!!

I don't need to be instructed in Chess Fundamentals!

It further annoys me as you think you can prove something to me with these "ABC's".....

Your proof to me...*sigh*

I am glad that you were able to understand my illustration that removing a piece does not always make the position that lost the piece weaker; that in fact there are times when you may wish one of your chessmen were removed from the board.

[deleted by moderation]

[smirobth]

Robin, you improvised and even removed the Black h6 pawn and EGTBs returned a draw. What , more proof do Dan and Uri need??

I agree with Dann that this is the least convincing proof I have read in this thread. The proposal "remove the h6 pawn, and it is still a draw" is useless, because from the first moment Uri asked for proof that Black cannot be placed in zugzwang. It is well known that in such Q v R endings, two protected squares is all the Rook needs in order to defend successfully. If you remove the h6 pawn, you immediately give the black rook a second protected square for free.

I would like to add that I find Robin's proof to be convincing. But if the h6 pawn was missing, the position becomes simpler to evaluate as a draw and his proof would be shorter. He would not have had to prove that the black Rook will always have an available square other than f6. The proof would be something like "Rf6-h6-f6-h6-f6-h6".

Finally would like to bring in the opinion of a expert on this position, namely Mark Dvoretsky. In the book "Dvoretsky's Endgame Manual", Chapter "Queen vs. Rook", paragraph "A Fortress with Multiple Pawns", he analyzes the following position

V. Khenkin, 1962
[d]8/4K2k/4Q1p1/5r1p/7P/8/8/8 b - - 0 1

1... Kh8!? (1... Kg7 and 1... Rf1 are also good) 2. Qxg6 Rf7+ 3.Ke6 Re7+ with a draw by stalemate or perpetual check.

With a shift up, the position is still drawn. But when shifted down, it is lost: White wins by means of a queen attack along the last rank.

So Dvoretsky says our position is drawn, because if we shift Khenkin's position up, we get the structure of the game Topalov-Mamedyarov.

You make some good points. However there is also a certain irony in your claim about the h-pawn removal "proof" being unconvincing (even though I sympathize with that point of view). In the original position under discussion removal of Black's h-pawn did not affect the drawn outcome (it is not hard to see that the rook has plenty of squares anyway), while in this new position removal of Black's h-pawn results in a position that is no longer a draw. Part of Black's problem is that in the new position without the h-pawn Black actually has fewer tenable squares for his rook, not more, since the rook now needs to try to stay on the 6th rank, to prevent White's pawn push.

[glorfindel]

Thanks for your insult. Removing the h6 pawn changes nothing, except one more redundant protected square.

I didn't mean to insult you and now that I have reread my post, I don't think I did. I just disagreed with you.

[glorfindel]

You make some good points. However there is also a certain irony in your claim about the h-pawn removal "proof" being unconvincing (even though I sympathize with that point of view). In the original position under discussion removal of Black's h-pawn did not affect the drawn outcome (it is not hard to see that the rook has plenty of squares anyway), while in this new position removal of Black's h-pawn results in a position that is no longer a draw. Part of Black's problem is that in the new position without the h-pawn Black actually has fewer tenable squares for his rook, not more, since the rook now needs to try to stay on the 6th rank, to prevent White's pawn push.

The next position illustrates my point better, and it is the one I should have posted earlier. It is Topalov - Mamedyarov shifted one rank to the left.

V.Khenkin, 1966
[d]1Q6/5pk1/4r1p1/3K2P1/8/8/8/8 w - - 0 1

Dvoretsky: As we know, a similar position, without the g6-pawn, is drawn. But here, when this pawn deprives the rook of the second protected square, White wins: he gradually approaches the black pawn using the zugzwang technique.

The main line he gives is 1. Qc7! (zugzwang) Re3 2. Qc2! Kg8 3. Kd6 Re6+ 4. Kd7 Re3 5. Qc4! (the Rook must leave the e-file) Ra3 6. Qe4 Kg7 7. Qe5+ Kg8 8. Qb8+ Kh7 9. Ke7 +-

[rlsuth]

Anyone have a 7 man tablebase generator?