1.g4 opening is losing?

[zullil]

That's a reason I hate such things, there's just no way to know when you're done...

Just perform a full (no reductions, no extensions) alpha/beta search to depth 52.

[Ovyron]

Is that some survival game where the challenge is staying alive until depth 52 is over?

[jp]

Here is another example
Stockfish needed a lot of time to find e4 and not e3 and could not see it at depth<95 (I used 1024 mbytes hash and 3 cores)
Note that chest with a single core was faster in seeing e4 is the only move that force mate in 8.

[d]1n2k3/8/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ - 0 1

Stockfish_20030109_x64_modern:
<snip>
94/18 08:44 3,206,095k 6,111k +M9 1.e3 Ke7 2.Bb5 Nd7 3.Qg4 Nf6 4.Qg7+ Ke6 5.Nc3 Kd6 6.Qxf6+ Kc7 7.Qc6+ Kb8 8.Ba6 Ka7 9.Qb7+
95/18 10:54 4,041,755k 6,171k +M8 1.e4 Nc6 2.Qh5+ Ke7 3.Qc5+ Kd7 4.d4 Nb4 5.Bb5+ Ke6 6.Qf5+ Ke7 7.Bg5+ Kd6 8.Qe5+

Komodo 13.2 shows mate in 8 from depth 21:

+M8 1.e4 Nd7 2.d4 Nf6 3.Qf3 Nd7 4.Bg5 Ne5 5.Bb5+ Nd7 6.Qh5+ Kf8 7.Bc4 Nf6 8.Qf7#

Surely this is largely luck, though, i.e. whether a given engine happened to like 1.e4 early, before the depths when it started announcing mates?

For the N on the other side,

[d]4k1n1/8/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ - 0 1

Komodo 13.2 does like 1.e3 to begin with, and switches to

+M8 1.e4 Nf6 2.Qf3 Nd7 3.d4 Kd8 4.Qf7 Kc7 5.Bf4+ Kc8 6.Ba6+ Kd8 7.Bb7 Ne5 8.Bg5#

around depth 25.

SF10 takes till depth 47 to find mate in 9 (with 1.e3) and did not find the mate in 8 at depths <=67.

[zullil]

For the N on the other side,

[d]4k1n1/8/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ - 0 1

Komodo 13.2 does like 1.e3 to begin with, and switches to

+M8 1.e4 Nf6 2.Qf3 Nd7 3.d4 Kd8 4.Qf7 Kc7 5.Bf4+ Kc8 6.Ba6+ Kd8 7.Bb7 Ne5 8.Bg5#

around depth 25.

SF10 takes till depth 47 to find mate in 9 (with 1.e3) and did not find the mate in 8 at depths <=67.

Sf-dev finds mate-in-8 at depth 52 (one thread, 16 GB hash)

info depth 52 seldepth 18 multipv 1 score mate 8 nodes 34076245 nps 2512071 hashfull 12 tbhits 0 time 13565 pv d2d4 g8f6 e2e4 e8d8 d1f3 f6e8 f3f8 d8d7 c1f4 d7e6 f1b5 e8f6 c2c4 f6e4 d4d5

[jp]

With both Ns, Black lasts a little longer.

[d]1n2k1n1/8/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ - 0 1

Komodo 13.2 finds mate in 11:

depth=22 +M12 1.e4 Nf6 2.e5 Nd5 3.Qg4 Ne7 4.Bb5+ Kd8 5.Qh4 Nc6 6.Bxc6 Kc7 7.Qxe7+ Kxc6 8.Qd6+ Kb7 9.e6 Ka7 10.e7 Kb7 11.e8=Q Ka7 12.Qeb8#

depth=23 +M11 1.e4 Nf6 2.Qf3 Nfd7 3.d4 Ke7 4.Bg5+ Kd6 5.Bd8 Nc6 6.Qf4+ Nde5 7.dxe5+ Kd7 8.e6+ Kxd8 9.Qd6+ Ke8 10.Qd7+ Kf8 11.Qf7#


SF10 find it around depth 32:

depth=33 +M11 1.e4 Nf6 2.d4 Nc6 3.Qf3 Ng8 4.Qh5+ Ke7 5.Bc4 Nf6 6.Qf7+ Kd8 7.Bg5 Ne7 8.Qxf6 Kc7 9.Qxe7+ Kb6 10.Qd7 Ka5 11.Qb5#

[fastgm]

Stockfish 11 C0 vs Stockfish 11 C0, 10 cores, 32 GB Hash
1.g4 d5, every move depth 60
Duration: 33 days

[pgn][Event "SF11 C0 - Depth 60"]
[Site "Talkchess"]
[Date "2020.02.06"]
[Round ""]
[White "Stockfish 11 C0"]
[Black "Stockfish 11 C0"]
[Result "0-1"]
[ECO "A00"]
[GameEndTime "2020-03-09T19:50:58.010 Mitteleuropäische Zeit"]
[GameStartTime "2020-02-06T00:15:14.274 Mitteleuropäische Zeit"]
[Opening "Grob's attack"]
[PlyCount "96"]
[TimeControl "inf"]

1. g4 {book} d5 {book} 2. e3 {-1.36/60 423121s} e5 {+1.34/60 89041s}
3. Nc3 {-1.35/60 87452s} h5 {+1.45/60 107757s} 4. g5 {-1.38/60 147274s}
Nc6 {+1.47/60 76506s} 5. h4 {-1.41/60 127904s} Bg4 {+1.72/60 49265s}
6. f3 {-1.65/60 86287s} Be6 {+1.80/60 41187s} 7. d4 {-1.60/60 54804s}
Nge7 {+1.80/60 114285s} 8. dxe5 {-1.88/60 87649s} Nxe5 {+1.88/60 23562s}
9. e4 {-1.69/60 37148s} g6 {+1.86/60 18488s} 10. Bg2 {-1.94/60 39591s}
Qd6 {+1.99/60 9545s} 11. Nge2 {-1.84/60 4635s} O-O-O {+2.14/60 4459s}
12. Bf4 {-1.83/60 2186s} Bg7 {+2.15/60 2655s} 13. Qd4 {-2.16/60 5395s}
N7c6 {+2.15/60 2031s} 14. Nb5 {-2.06/60 1891s} Qb4+ {+2.14/60 2549s}
15. Qxb4 {-2.06/60 300s} Nxb4 {+2.11/60 1465s} 16. O-O-O {-2.07/60 2979s}
dxe4 {+2.11/60 162s} 17. fxe4 {-2.07/60 630s} Rxd1+ {+2.11/60 440s}
18. Kxd1 {-2.20/60 1933s} Rd8+ {+2.11/60 133s} 19. Kc1 {-2.20/60 68s}
Bc4 {+2.11/60 31s} 20. Bh3+ {-2.20/60 335s} Ng4 {+2.11/60 92s}
21. Nbc3 {-2.24/60 1255s} Nxa2+ {+2.11/60 187s} 22. Nxa2 {-2.24/60 390s}
Bxe2 {+2.11/60 14s} 23. Nc3 {-2.23/60 418s} Bxc3 {+2.11/60 161s}
24. bxc3 {-2.24/60 196s} Re8 {+2.11/60 141s} 25. Bg2 {-2.34/60 828s}
a5 {+2.22/60 553s} 26. Kd2 {-2.34/60 617s} Bb5 {+2.22/60 213s}
27. Kc1 {-2.34/60 266s} Bc4 {+2.32/60 1099s} 28. Kb2 {-2.34/60 298s}
Re6 {+2.42/60 286s} 29. Rd1 {-2.34/60 374s} Rb6+ {+2.42/60 359s}
30. Ka1 {-2.34/60 112s} Rc6 {+2.31/60 349s} 31. Kb2 {-2.34/60 103s}
b6 {+2.31/60 81s} 32. Rd2 {-2.34/60 133s} Rc5 {+2.95/60 4945s}
33. Rd4 {-2.34/60 64s} Be6 {+2.95/60 486s} 34. Bf1 {-2.45/60 1294s}
b5 {+2.95/60 2212s} 35. Rd1 {-2.88/60 3035s} Ne5 {+3.27/60 2355s}
36. Kb1 {-3.36/60 6020s} Nc4 {+3.49/60 2832s} 37. Rd4 {-3.57/60 3597s}
a4 {+3.70/60 5193s} 38. Bc1 {-4.02/60 5500s} Kb7 {+3.81/60 971s}
39. Bg2 {-4.83/60 23746s} a3 {+4.82/60 8366s} 40. Rd1 {-4.91/60 1928s}
Kc8 {+4.82/60 601s} 41. Rg1 {-4.91/60 1127s} Rc6 {+4.82/60 55s}
42. Bf1 {-5.15/60 3182s} Ra6 {+4.93/60 1233s} 43. Bd3 {-5.26/60 1944s}
Kb7 {+5.42/60 5083s} 44. Rf1 {-5.74/60 12118s} c5 {+5.54/60 4817s}
45. Ka1 {-6.22/60 12246s} Kc6 {+6.30/60 12148s} 46. Rf6 {-7.18/60 60789s}
Ne5 {+8.06/60 63980s} 47. Bf1 {-7.31/60 4768s} Ra4 {+8.57/60 24565s}
48. Rf4 {-7.44/60 5113s} Kb6 {+10.62/60 139452s} 49. Be2 {-11.00/60 745881s} 0-1[/pgn]

[zullil]

Stockfish 11 C0 vs Stockfish 11 C0, 10 cores, 32 GB Hash
1.g4 d5, every move depth 60
Duration: 33 days

[pgn][Event "SF11 C0 - Depth 60"]
[Site "Talkchess"]
[Date "2020.02.06"]
[Round ""]
[White "Stockfish 11 C0"]
[Black "Stockfish 11 C0"]
[Result "0-1"]
[ECO "A00"]
[GameEndTime "2020-03-09T19:50:58.010 Mitteleuropäische Zeit"]
[GameStartTime "2020-02-06T00:15:14.274 Mitteleuropäische Zeit"]
[Opening "Grob's attack"]
[PlyCount "96"]
[TimeControl "inf"]

1. g4 {book} d5 {book} 2. e3 {-1.36/60 423121s} e5 {+1.34/60 89041s}
3. Nc3 {-1.35/60 87452s} h5 {+1.45/60 107757s} 4. g5 {-1.38/60 147274s}
Nc6 {+1.47/60 76506s} 5. h4 {-1.41/60 127904s} Bg4 {+1.72/60 49265s}
6. f3 {-1.65/60 86287s} Be6 {+1.80/60 41187s} 7. d4 {-1.60/60 54804s}
Nge7 {+1.80/60 114285s} 8. dxe5 {-1.88/60 87649s} Nxe5 {+1.88/60 23562s}
9. e4 {-1.69/60 37148s} g6 {+1.86/60 18488s} 10. Bg2 {-1.94/60 39591s}
Qd6 {+1.99/60 9545s} 11. Nge2 {-1.84/60 4635s} O-O-O {+2.14/60 4459s}
12. Bf4 {-1.83/60 2186s} Bg7 {+2.15/60 2655s} 13. Qd4 {-2.16/60 5395s}
N7c6 {+2.15/60 2031s} 14. Nb5 {-2.06/60 1891s} Qb4+ {+2.14/60 2549s}
15. Qxb4 {-2.06/60 300s} Nxb4 {+2.11/60 1465s} 16. O-O-O {-2.07/60 2979s}
dxe4 {+2.11/60 162s} 17. fxe4 {-2.07/60 630s} Rxd1+ {+2.11/60 440s}
18. Kxd1 {-2.20/60 1933s} Rd8+ {+2.11/60 133s} 19. Kc1 {-2.20/60 68s}
Bc4 {+2.11/60 31s} 20. Bh3+ {-2.20/60 335s} Ng4 {+2.11/60 92s}
21. Nbc3 {-2.24/60 1255s} Nxa2+ {+2.11/60 187s} 22. Nxa2 {-2.24/60 390s}
Bxe2 {+2.11/60 14s} 23. Nc3 {-2.23/60 418s} Bxc3 {+2.11/60 161s}
24. bxc3 {-2.24/60 196s} Re8 {+2.11/60 141s} 25. Bg2 {-2.34/60 828s}
a5 {+2.22/60 553s} 26. Kd2 {-2.34/60 617s} Bb5 {+2.22/60 213s}
27. Kc1 {-2.34/60 266s} Bc4 {+2.32/60 1099s} 28. Kb2 {-2.34/60 298s}
Re6 {+2.42/60 286s} 29. Rd1 {-2.34/60 374s} Rb6+ {+2.42/60 359s}
30. Ka1 {-2.34/60 112s} Rc6 {+2.31/60 349s} 31. Kb2 {-2.34/60 103s}
b6 {+2.31/60 81s} 32. Rd2 {-2.34/60 133s} Rc5 {+2.95/60 4945s}
33. Rd4 {-2.34/60 64s} Be6 {+2.95/60 486s} 34. Bf1 {-2.45/60 1294s}
b5 {+2.95/60 2212s} 35. Rd1 {-2.88/60 3035s} Ne5 {+3.27/60 2355s}
36. Kb1 {-3.36/60 6020s} Nc4 {+3.49/60 2832s} 37. Rd4 {-3.57/60 3597s}
a4 {+3.70/60 5193s} 38. Bc1 {-4.02/60 5500s} Kb7 {+3.81/60 971s}
39. Bg2 {-4.83/60 23746s} a3 {+4.82/60 8366s} 40. Rd1 {-4.91/60 1928s}
Kc8 {+4.82/60 601s} 41. Rg1 {-4.91/60 1127s} Rc6 {+4.82/60 55s}
42. Bf1 {-5.15/60 3182s} Ra6 {+4.93/60 1233s} 43. Bd3 {-5.26/60 1944s}
Kb7 {+5.42/60 5083s} 44. Rf1 {-5.74/60 12118s} c5 {+5.54/60 4817s}
45. Ka1 {-6.22/60 12246s} Kc6 {+6.30/60 12148s} 46. Rf6 {-7.18/60 60789s}
Ne5 {+8.06/60 63980s} 47. Bf1 {-7.31/60 4768s} Ra4 {+8.57/60 24565s}
48. Rf4 {-7.44/60 5113s} Kb6 {+10.62/60 139452s} 49. Be2 {-11.00/60 745881s} 0-1[/pgn]

Thanks for the data point! I assume "C0" means "Contempt = 0". What endgame tables were the engines using?

[Ovyron]

You still think it's drawn zullil? What do you think someone could do to find a single drawing line for white? (to at least put the ball on the other camp, people having to find a black win against that line)

[fastgm]

Thanks for the data point! I assume "C0" means "Contempt = 0". What endgame tables were the engines using?

Yes, "C0" means Contempt = 0
All 6-men syzygy tablebases were used.

Complete logfiles: http://www.fastgm.de/schach/1.g4-d5_log.7z

Andreas

[jp]

For absolute proofs, 13 is pretty well the limit for chest319

But ChestUCI has special parameters for much deeper mates. I have found mates of more than 60 plies with ChestUCI. However, you lose the "proof of minimal mate" in the special ChestUCI mates. So it finds a sure mate, but there could be a shorter one.

I see. That could be useful to know.

Stockfish 11 C0 vs Stockfish 11 C0, 10 cores, 32 GB Hash
1.g4 d5, every move depth 60
Duration: 33 days

Great!

You still think it's drawn zullil? What do you think someone could do to find a single drawing line for white?

If it requires a "tablebase-like" draw, it's going to be very hard to find.