How to complete a checkmate in this game? I have seen the ending position of this game in between Nakamura and Harikrishna. I sense a checkmate is close, but can't figure out what white should do after Qxg7. Please tell me how to complete the checkmate.

http://www.chessgames.com/perl/chessgame?gid=1744377

After 33... Qxg7, 34. Qxg7 is just mate in one. The queen is protected by the knight on h5. Black cannot avoid short-term mate at all, because Qxh7# is also a threat. He can stave it off with some desperate checks by the queen, e.g. 33... Qa1+ 34. Kh2 Qh1+ 35. Kxh1 but it is mate next move.

[FEN ""]
[White "Pentala Harikrishna"]
[Black "Hikaru Nakamura"]

1. e4 c5 2. Nf3 d6 3. Bb5 Nd7 4. O-O a6 5. Bd3 Ngf6 6. c3 b5 7. Bc2 Bb7 8. Re1 e5 9. d4 Be7 10. Nbd2 O-O 11. Nf1 Re8 12. Ng3 Bf8 13. d5 g6 14. b3 Nb6 15. Rb1 c4 16. bxc4 Nc4 17. a4 Qc7 18. axb5 axb5 19. Rb5 Na3 20. Rb3 Nc2 21. Qc2 Nd7 22. Be3 Ba6 23. Ra3 Bb5 24. Rea1 Ra3 25. Ra3 Rb8 26. Ra7 Qc8 27. h3 Nb6 28. Qc1 Nc4 29. Bh6 Qc5 30. Nh5 Bg7 31. Bg7 Qa7 32. Qh6 f5 33. Ng5 Qxg7 34. Qxg7#


What is the purpose of 12.a3 in the QGD Lasker Defence? this is about queen gambit declined lasker defence :

[fen ""]
1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. e3 O-O 6. Nf3 h6 7. Bh4 Ne4 8. Bxe7 Qxe7 9. Rc1 Nxc3 10. Rxc3 c6 11. Qc2 Nd7 12. a3

why or what is the purpose of  12.a3 ?

12. a3 in this position is a very concrete move, and as such, the best way to understand its purpose is to play out a handful of the main variations with and without the a3 inclusion. If it's difficult to do that on your own, keep an engine on your side while you're doing your exploratory analysis.

Short answer: a3 is not necessarily needed for white here, as there are alternatives such as Be2 (see Ivanchuk vs Carlsen 2012), but a3 helps keep a slight additional edge for white, as in a number of lines that can ensue white will have stopped any options of Qb4+, Qb5 (stopping white's castling) and Nf6-Nd5-Nb4 (specially in lines where black opts for b6.) To see why either of these options are relevant, let's go through some lines.

Longer answer (annotated, first go through the lines without a3):

 [title "Without and with a3 from move 12"]
 [fen "r1b2rk1/pp1nqpp1/2p1p2p/3p4/2PP4/2R1PN2/PPQ2PPP/4KB1R w K - 2 12"]

 1. Be2 (1. a3 {for the sake of comparison, let's follow through with both sides similarly to the Be2 line in order to highlight the underlying difference} dxc4 2. Bxc4 b6 3. Bd3 Nf6 (3...Bb7 {connecting the rooks and defending c6 directly} 4. Be4 Rfc8 5. Bxc6 {if c6-c5 could be played after Be4, black would be fine, but the knight on d7 leaves the queen and bishop disconnected, therefore, leaves c6 stuck on c6 and black cannot muster enough defense to hold on to it. So in this subvariation black still loses a clear pawn. We can conclude that after a3, black cannot really proceed with dxc4 and b6 ideas to finish development. However, dxc4 followed by e5 seems like a better alternative, but that's another discussion altogether.}) 4. Rxc6 Nd5 5. Qe2 Bb7 6. Rc1 {thanks to a3, white's a safe pawn up, has avoided simplifications for black, kept a healthy pawn structure and is ready to castle and maintaining control over the open file. Thus, a3, clearly refutes Nf6-Nd5 and leaves c6 hanging for black, so let's do better for black now.}) {Simply focusing on kingside development and to prepare short castles} dxc4 {a key forcing line that emphasizes the importance of control of b4 square} 2. Bxc4 b6 {in order for black to finish development, a solution has to be found for the locked out c8 bishop, therefore, either one opts for the e5 break early enough, or sets up the bishop on the long diagonal with b6, with either pawn breaks c5-e5 postponed for later.} 3. Bd3 {white's immediate reaction should be to prevent black's easy development, which here is simply to pressure the vulnerable c6 pawn, so Bd3 both uncovers the semi-open file and keeps the option of Be4 to add more pressure on c6.} Nf6 (3...Bb7 {for completeness let's consider the immediate Bb7 as well} 4. Be4 {usually throwing a Bh7+ first is good, but for the purpose of our discussions here it's not so important.} Rac8 5. Bxc6 Bxc6 6. Rxc6 Rxc6 7. Qxc6 Qb4+ {b4's not controlled by white!} 8. Qc3 Qb5 {black's well compensated for the pawn as white's unable to finish development and bring its last piece into play, black seems to be well in time for Nf6-Ne4-Nd6 followed by Rc8 claiming the open file, while white's left with no real initiative or even a clear path to finishing development.}) {but Bd3 is not even with tempo because black doesn't even have to immediately respond to the defense of c6 as Nf6 followed by Nd5 indirectly defends c6 as it comes with a double attack threat of Nb4 either forking the rook and queen, or the queen and bishop.} 4. Rxc6 Nd5 5. Qd2 {side-stepping the fork} Nb4 {b4's not controlled by white!} 6. Rc3 Nxd3+ 7. Qxd3 Bb7 8. O-O (8. Qe2 {as an alternative attempting not to prevent the kingside damage and holding on to the extra pawn} Rfc8 9. O-O Rxc3 10. bxc3 Rac8 11. Rc1 Qa3 12. Qd2 Bd5 {black's completely equalized as white's both weak pawns are under pressure and white has no initiative, Rc2 Be4 can even potentially lead to repetition.}) Bxf3 9. gxf3 Qg5+ 10. Kh1 Qd5 {black's winning back the temporarily sacrificed pawn and has a perfectly playable position without any weaknesses. This shows that Nf5-Nd5 is a very strong idea and if white wants to stop all these forcing variations which heavily simplify and equalize the game, then the said knight maneuver has to be stopped.}

Summary after our analysis: Very concretely, a3 puts a clear stop to dxc4 and b6 type of continuations for black (which would let them complete development comfortably), while maintaining the asymmetry of the position and avoiding simplifications which would favour black.  Black on the other hand, still has a number of choices at their disposal after a3, one of which is dxc4 followed by e5, either way, black has to have planned for a well-timed pawn break with c5 or e5 if and when they decide to take on c4.


Do you accept takebacks? If somebody playing with you propose a takeback, how often will you accept it? Do you know if takebacks are allowed on tournaments?

Regarding tournaments, according to the FIDE rules, takebacks are not permitted.  Section 4.6:

  When, as a legal move or part of a legal move, a piece has been released on a square, it
  cannot be moved to another square on this move. The move is then considered to have
  been made:

(The rest of section four has more rules about touching a piece, moving a piece, capturing a piece, and the like - but the gist of the answer is there: once a move is made, it has been made.)

Regarding casual games... that's entirely up to you.  In general, I prefer touch move and no takebacks regardless of the game - but sometimes, if it was a very good game, it's nice to say, "sure, you win... but what would have happened if..." and play it out a different way.


The Anderssen v Zukertort game in the Yamie Chess kids' math boardgame Spanish Game: Johannes Zukertort vs Adolf Anderssen 1865 - Berlin

[fen ""]
[White "Zukertort"]
[Black "Anderssen"]
[Event "Berlin 1865"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 Nge7 4. c3 d6 5. d4 Bd7 6. O-O Ng6 7. Ng5 h6 8. Nxf7 Kf7 9. Bc4 Ke7 10. Qh5 Qe8 11. Qg5 hxg5 12. Bg5#

To give my question some pre-text, my friend Mato has done a quick YouTube analysis on this Anderssen-Zukertort game here which dates back to 1860s Germany I believe: https://www.youtube.com/watch?v=wCV45-Kaxy0

Thought I'd ask this here: There's a truly astonishing queen sacrifice in a math practice game that my daughter has come home from scouts with (she's attending an Atlanta charter school), and it's got me thinking about whether Adolf Anderssen was the "world leading" unparalleled tactician that some 1980's chess theory books celebrate him as. I'll disclose that I hadn't seen this classic Zukertort game before, so you'll have to forgive me if there is an analysis line of thought on this somewhere that I haven't turned up on google yet.

The kids' math game itself is called Yamie Chess (its aimed at middle school kids and been done by the looks of things by a US Woman's chess master called Jennifer Shahade) and it basically frames the above old grandmaster chess line of Zukertort v Anderssen with the spanish opening--quite astonishingly--through a Disneyesque cartoon style story, that presents a series of math lessons and puzzles that kids have to solve all the while interactively re-enacting this Anderssen game on the board almost like passing nintendo levels to move on to the next chapter. But all done with chess. It's long too... 250+ pages to get through the whole Anderssen game.

My question relates to 8.Nxf7 in the late middle game.

So, 8.Nxf7... isn't that a weak move? If not, why not? I was thinking 8...Kxf7 9.Bc4+ Ke7?.. as Ke8 could give Black some advantage. I just think it seems weird that Anderssen didn't see this coming. What is going on?

I appreciated that the Yamie Chess comic doesn't labor this line, actually the comic somehow manages to combine 8.Nxf7--if you can believe it--with a section on transitive properties in school algebra. Dumbed down common core math, it ain't.

Objectively, I think you are right that 8.Nxf7 is a somewhat weak move. But it is also an unsettling, complicating move that poses a concrete defensive problem, enough of one in fact that a (truly!) great tactician like Anderssen made a serious misstep. You are also right that the main culprit in Anderssen's defeat was 9...Ke7?, and that 9...Ke8 is far preferable objectively. So why might Anderssen have played it (besides the possibility that he may have just blundered, as all the greats have done)?

One plausible reason is that that alternative 9...Ke8 itself perhaps looked hopeless. It invites the same move as in the game, 10.Qh5, with the difference that in this line the knight is pinned. Only two moves could save it: 10...Ne7 or 10...Qf6. Each can be best met by 11.f4, and it turns out that in the 10...Ne7 line the g6 knight is lost anyway (see board below). The move 10...Qf6 (which again is an ostensibly uncomfortable move to consider, lining up the black queen against the white rook on a soon-to-be open file) does save the day and leave Black with the advantage, but only with very precise play: 11.f4 exd4! 12.f5 Ne5 13.fxg6 Bg4!. I'm going to trust Stockfish here in saying that each of those ! moves is the only one to leave Black to the better.

It's very plausible that back at move 9 Anderssen didn't see that defensive possibility materializing. He may have thought he was already lost and that not walking into the pin was his best practical chance. After 9...Ke7?, if Anderssen can just get a chance to catch his breath and run away with ...Qe8 and ...Kd8, he will be better. The only move to stop that plan is the game's 10.Qh5!, and at that point White really is just winning, as there is no way to save the knight. So Anderssen probably just threw up his hands and continued with 10...Qe8. Then, either Zukertort plays the mate that he did, or Anderssen escapes; it was already out of Anderssen's hands at that point.

[fen ""]
[White "Zukertort"]
[Black "Anderssen"]
[Result "1-0"]

1.e4 e5 2.Nf3 Nc6 3.Bb5 Nge7 4.c3 d6 5.d4 Bd7 6.O-O Ng6 7.Ng5 h6 8.Nxf7
Kxf7 9.Bc4+ Ke7?
    ( 9...Ke8 10.Qh5 Qf6!
        ( 10...Ne7 11.f4 exf4 12.Rxf4 )
    11.f4 exd4!
        ( 11...exf4? 12.Rxf4 )
    12.f5 Nce5 13.fxg6 Bg4! 14.Qxg4 Nxg4 15.Rxf6 Nxf6 )
10.Qh5 Qe8
    ( 10...Be8 11.Bg5+ hxg5 12.Qxg5+ Kd7 13.Qf5+ Ke7 14.Qe6# )
    ( 10...Nf4 11.Qf7# )
11.Qg5+ hxg5 12.Bg5#


Why is e6 "forced" in this position? Larry Christiansen has played and analysed his four games against Chessmaster.

At the 8th move, he shows a different possible continuation and says that e6 (shown below) is forced for black. I don't see why black would be any worse if another move is played, so why is this forced? For instance, is g6 not possible?

[FEN ""]
1. Nf3 c5 2. e3 Nc6 3. c4 Nf6 4. d4 d5 5. cxd5 Nxd5 6. e4 Nf6 7. d5 Nxe4 8. dxc6 Qxd1+ 9. Kxd1 Nxf2+ 10. Ke1 Nxh1 11. Bb5 b6 12. c7+ Bd7 13. Ba6 e6

White has some nasty threats involving the loose a8-rook and c7 pawn. After 13...g6:

[FEN ""]
[StartPly "26"]

1. Nf3 c5 2. e3 Nc6 3. c4 Nf6 4. d4 d5 5. cxd5 Nxd5 6. e4 Nf6 7. d5 Nxe4 8. dxc6 Qxd1+ 9. Kxd1 Nxf2+ 10. Ke1 Nxh1 11. Bb5 b6 12. c7+ Bd7 13. Ba6 g6 14. Bb7 Rc8 {Saving material} 15. Bf4 {Defending the passed pawn} Bg7 {Carrying on with the planned fianchetto} 16. Bxc8 Bxc8 17. Nc3 {White will be able to take the trapped h1 knight soon or even play Ra1-d1-d8#}

However, playing 13...e6 allows the black king to attack the c7 pawn, preventing white cramping down like this.

N.B. Not checked by an engine. These are just my first impressions.


Strongest / most aggressive 1. d4 openings I'm curious to know what are some of the 1. d4 openings (Queen's Pawn), especially if they are highly agressive and/or are regularly used at higher GM level of play.

I really want to learn all I can and focus on d4 openings everytime I get to play white. I currently play the London System Opening.

All recomendations are welcome.

I feel that the most ambitious, principled and aggressive 1.d4 repertoire is the one given by John Cox in his book "Starting Out: 1.d4!". Of course these are the most ambitious lines for white in chess so they have also got extreme amounts of published theory and as they lead to very sharp positions, not knowing the theory may lead to quick losses for white.

The main criticism of the book was that a collection of lines fit for top players may not be suitable for the audience of "Starting Out" books, but you don't ask for easy openings :-). Ironically even the world top has now moved away somewhat from these lines because the theory had been worked out so far, they go for slightly more restrained lines with g3 or so more of the time these days.

It is based on 1.d4 Nf6 2.c4 and 1.d4 d5 2.c4.

The following list of the lines it offers is from Watson's review of the book (http://theweekinchess.com/john-watson-reviews/the-end-of-openings-part-1), as I don't have the book with me right now:

  Cox's book suggests a complete repertoire for White beginning with 1
  d4. Here are a few of the main systems that he recommends:

  (a) versus the King's Indian: the main line 4 e4/5 Nf3/6 Be2/7 0-0 and 9 b4, the Bayonet Variation, , one of the most theoretical lines possible, with
  Black systems to cope with on every move that leads up to that move;

  (b) versus the Grünfeld: the main line of the 7 Nf3/8 Rb1 system, that
  is, the one that Edward Dearing recently wrote a densely-packed
  205-page book about;

  (c) versus the Nimzo-Indian: 4 Qc2 and pretty
  much every main-line line that follows this most investigated of
  modern lines;

  (d) versus the Benoni: the Modern Main Line with h3 and
  Bd3, again the most-analysed current variation;

  (e) versus the Benko
  Gambit: g3 and Bg2 with the contemporary main variation 10 Rb1;

  (f) versus the Queen's Gambit Declined: the main line Exchange Variation
  with the sharp Nge2;

  (g) versus the Tarrasch Defence, the main line: 6
  g3/9 Bg5, also ridden with traps and tricks to remember;

  (h) versus
  the Slav Defence: the main line with 6 Ne5, the most theoretical and
  complicated Slav line ;

  (i) versus the Semi-Slav: the main line
  Botvinnik Attack, one of the most-analysed variations in all of chess
  history.


what is the shortest allowable time control for a FIDE rated standard tournament game? My chess club wants to host a FIDE tournament in a couple of months with 3 FIDE rated games in one day.

What is the shortest allowed time control for FIDE rated standard tournament games so we can fit in all 3 games on one day?  Thanks!

Best,
Richard

According to the FIDE Rating Regulations, it depends on the player ratings:

  1.1 For a game to be rated each player must have the following minimum periods in which to complete all the moves, assuming the game lasts 60 moves.
  Where at least one of the players in the game has a rating 2200 or higher, each player must have a minimum of 120 minutes.
  Where at least one of the players in the game has a rating 1600 or higher, each player must have a minimum of 90 minutes.
  Where both of the players in the game are rated below 1600, each player must have a minimum of 60 minutes.

  1.2 Where a certain number of moves is specified in the first time control, it shall be 40 moves.


What service can be used to save and replay/analyze a chess match? I've been starting to write down my chess matches in a scorebook, but would like to find a site where I can transcribe the match and then replay move by move by game to help me analyze what I did well and where I made mistakes.

I remember accidentally finding this kind of a SAAS a while ago, but I never bookmarked it, and don't even know what to search for anymore.

Can anyone give me some pointers what to search for, or recommend a site that can provide this kind of service?

For an online tool, lichess is good. You can enter your game and have it analysed by a computer engine.

The analysed game will have annotations in plain language ("mistake/blunder/inaccuracy") and of course contain the computer evaluation score after each move.

Once you have a game analysed on lichess, they have another good feature called: "Learn from your mistakes". Here it will ask you at every mistake/blunder to find a better move.

Another feature which might help you is called "chess insights", basically statistics of your games (e.g. which opening did you score best, etc).

You can do much the same (and more) offline using a chess database software. Scid is a popular free one, chessbase a popular non-free one. However as a beginner you might find the lichess features sufficient and more easy to use. In any case you can import/export between lichess and chess databases.

Particularly for a beginner it is difficult to properly analyze a game. Computers will tell you about tactical mistakes, but finding problems in strategy/positional play using computers will be just about impossible on your own. Therefore I would suggest to find a stronger player look over your games and give you tips. Ideally you'd join a chess club, but if that's not an option you could also post your games in online forums.

Another way to improve is to read or watch commented games, particularly those in the openings you play.


How do you know whether to trade one of the rook pairs in an endgame? I've been reading Endgame Strategy. I've seen, in a lot of the games, trading one of the rook pairs can help. There is a chapter in the book called the 'Problem with Exchanging.' I don't know how to determine when trading one of the rooks is beneficial for me.

One question to ask is "am I behind or ahead?"  If I have some winning edge, it's best to simplify.  If I'm behind, it's better to complicate the position.

After that, the question has both tactical and positional elements.  If my rook is less active then my opponent's, it's better to exchange.  If my rook is more active, then it's better to keep it.


Draw, or discovered check It's my move.  All I have is a king.  The opponent has a rook and a queen.  I can't move without going into check.  Is this a draw?

That's the definition of a "stalemate", which is a draw, i.e. if it's your turn to move and your lone king has no legal move.  It can also happen in other situations, such as for example if you also have blocked pawns on the board in addition to the king, since you will still have no legal move. This is often the last resort of the novice, the hope that his opponent will let him obtain such a position. If you are the player with the rook and queen, or even just a queen, in such a situation, you must be careful to always leave your opponent's king a space to move to if you don't have an immediate mate to avoid this occurring.  Of course, it's much less likely that you can get a stalemate against a more skilled opponent, although some strong players have "swindled" their equally strong opponents out of a win thereby, one famous case being a long-ago game between Grandmasters Larry Evans and Samuel Reshevsky.


What is the legend of Ossip Bernstein, who supposedly played chess to save his life? Wikipedia article reads as following:

A famous story goes that in 1918, after the October Revolution, Bernstein was arrested in Odessa by the Cheka (Bolshevik secret police). He was ordered to be shot by a firing squad because he was a legal advisor to bankers. As the firing squad lined up, a superior officer asked to see the list of prisoners' names. Discovering the name of Ossip Bernstein, he was asked whether he was the famous chess master. Not satisfied with Bernstein's affirmative reply, the officer made Bernstein play a game with him. If Bernstein lost or drew, he would be shot. Bernstein won in short order and was released. He escaped on a British ship and settled in Paris.

Is this story entirely true? Any sources are there to support it?

The written sources appear to be:

An obituary on Bernstein by Edward Lasker (a friend of Bernstein) in the April 1963 issue of Chess Review, which is described in the link below, including a scan of the 1963 article itself: http://jewishchesshistory.blogspot.com/2009/09/alekhine-escaping-execution-definite.html

However, the US Chess Federation has made it also available on their site on page 104: http://uscf1-nyc1.aodhosting.com/CL-AND-CR-ALL/CR-ALL/CR1963/CR1963_04.pdf

A book by Arnold Denker, mentioned in the Wikipedia article itself, 'The Bobby Fischer I knew and Other Stories'. Denker seems to indicate that he also heard the story from Bernstein himself and that he always believed it.


The Meran System plan of attack I've recently started to play the triangle system against the Queen's gambit, and so far it is okay. I've extensive knowledge in the Noteboom variation, but the problem with it is that the variation can be easily be avoided by White (since it is such a sharp line).

So I decided to search for a fall back plan.

I mean, I've just been doing the automatic c5 counters when Noteboom was turned down, but I've stumbled across this system called the Meran system.

Can you tell me the theory behind this system?

On the surface it looks like Black is supposed to advance on the Queenside, but I'm fuzzy on the details, nor this "Anti-Meran".

Thanks!

If black plays the triangle system againts the Queen's Gambit, white can (try to) transpose to the Semi-Slav defence: 1.d4 d5 2.c4 e6 3.Nc3 c6 4.e3 Nf6 5.Nf3 Nbd7.

The line 6.Bd3 dxc4 7.Bxc4 b5 is called the Meran. White can avoid this, by playing the Anti-Meran: 6.Qc2. A good summary can be found on Wikipedia.

According to the Game Database of ChessTempo, 4....Nf6 and 5....Nbd7 are by far the most popular replies for black. The Semi-Slav is known to be a good and solid defence.

An alternative for black is 5....a6, which was played many times by Anand in his WCC-match against Gelfand.

An other idea is to transpose to the Stonewall. You can play 4....f5 immediately or wait a couple of moves like in the game Kasimdzhanov-Grischuk.

      [FEN ""]
      [StartPly "7"]

      1.d4 d5 2.c4 e6 3.Nc3 c6 4.e3 Nf6 (4...f5)(4...Nd7 5.Qc2 Nh6 6.Bd2 f5) 5.Nf3 Nbd7 (5...a6) 6.Bd3 (6.Qc2) dxc4 7.Bxc4 b5


When is it appropriate for the arbiter to reduce a player's time? According to the FIDE Laws of Chess:

  12.9 Options available to the arbiter concerning penalties:

  12.9.1 warning,

  12.9.2 increasing the remaining time of the opponent,

  12.9.3 reducing the remaining time of the offending player,

  12.9.4 increasing the points scored in the game by the opponent to the maximum available for that game,

  12.9.5 reducing the points scored in the game by the offending person,

  12.9.6 declaring the game to be lost by the offending player (the arbiter shall also decide the opponent’s score),

  12.9.7 a fine announced in advance,

  12.9.8 exclusion from one or more rounds,

  12.9.9 expulsion from the competition.

In a FIDE rated competition (or one in which the FIDE laws apply) when is it appropriate to apply a time reduction as a penalty?

I know of one such, which I will give as a separate answer. I would like to know if there are more.

According to the FIDE Laws of Chess:

  8.1.1 In the course of play each player is required to record his own moves and those of his opponent in the correct manner, move after
  move, as clearly and legibly as possible, in the algebraic notation
  (Appendix C), on the ‘scoresheet’ prescribed for the competition.

In Israel a lot of the leagues play on a Saturday between 10 am 2 or 3 pm. Obviously all of the people who play have religious beliefs which are consistent with this, unlike Samuel Reshevsky who refused to play on the Sabbath. There are, though, a very small number of players who's beliefs allow them to play chess on the Sabbath but not write the moves down because that resembles the work of a scribe, could therefore be construed as work, and is there fore forbidden to them.

In this situation it has been agreed with the the arbiters overseeing the competition that these players may be excused the requirements of article 8.1.1 but must suffer a time penalty of 10 minutes. So, in a 90+30 game (all moves in 90 minutes with a 30 second increment from move 1) they start with 80 minutes on the clock plus increment instead of 90.

This is actually mentioned in article 8.1.6:

  8.1.6 If a player is unable to keep score, an assistant, who must be acceptable to the arbiter, may be provided by the player to write the
  moves. His clock shall be adjusted by the arbiter in an equitable
  way. This adjustment of the clock shall not apply to a player with a
  disability.

It is worth noting that players with disabilities are not subject to this time penalty.

I've applied this principle in mid-week tournaments where a player has refused from move 1 to write the moves down and also refused to give an explanation. Such a solution is obviously preferable to trying to coerce the player or to exclude the player from the competition, both of which would be highly undesirable.


Chess variation where the goal is to lose all pieces A friend challenged me to a chess variation I have never heard of.

All chess rules apply.
If you have an opportunity to take a piece, you must take it, you cannot avoid or block exchanges.
The only piece that cannot be taken is the king and there's no checkmate but you can check the king, and you can castle.
The strategy is to force your opponent to take all your pieces.
The winner is the one who has no pieces on board except the king.

Questions:

Have you ever heard of this variation before? What is it called? Is it formally recognized like Chess960?
I played black and lost all the matches. Does White have a decisive advantage since he can play d4 followed by Bh6, and losing a piece and stay ing one move ahead? This variation does not seem fair because it looks like a race to lose everything, hence White will win the race by force every time.
If it exists and have a community, what are the main tactics and strategies, especially when playing black?

I played black and lost all the matches. Does white have a decisive advantage since he can play d4 followed by bh6 and lose a piece and stay one move ahead?

According to Dr Mark Watkins of The University of Sydney, losing chess has been solved and White can force a win with 1. e3:

  The move 1. e3 has been solved as a win for White under both FICS and
  International Rules. The final leg was actually much easier than expected,
  as I wasted around a year on false leads. In fact, the not-too-deep idea
  1. e3 b6 2. a4 e6 3. Ra3 Bxa3 4. Nxa3 Qh4 5. a5 bxa5 6. Qh5! leads to
  some queen races where White just needs a bit deeper search to show
  a good score


For team events, what is the correct way to record a player's team in PGN format? More or less as the title. I'm helping transcribe some games for a team tournament that is happening, but I can't find any field in the software I'm using or even the PGN format specification for a 'Team' field. Considering that this problem must have occurred before for high-profile team events (Olympiad, Bundesliga, etc.), is there an accepted way to record this information in a PGN file?

There are two fields I have seen used extensively for this purpose: WhiteTeam and BlackTeam.

They don't appear to be documented in the PGN Standard, but don't let that discourage you.

As one example, I have found these fields present in the Olympiad 2016 Baku PGN games download file. They are also present in any PGN file created from a MegaBase database for a team tournament. They are also included in every PGN file published by The Week In Chess (TWIC) by Mark Crowther and by ChessBase Magazine, such as the World Team Championships, the French, Swedish and Hungarian Team Championships, the United States Chess League, the European Club Cup, and so on.

This means they are populated by publishers of game scores, and also that they are stored in a CBH-format database. The PGN handler for ChessBase will both export and import these fields within the PGN data.


How does Lichess rating compare to USCF? Just wondering some examples of peoples' USCF rating to Lichess (classic lichess, 10 min+)

I know it's hard to compare different pools of players. But I think that considering how we do polling with sample sizes, the numbers could be similar once you have the appropriate offset calculated. I need examples of comparisons of the ratings, to know "what's the average offset"?

I figure if I am in the top 90% Percentile in lichess, then I should be at least top 70% in USCF or some comparison like that. (just as an example)

There is unfortunately no 'good' way to convert from Glicko-2 to ELO. While a lot of people claim they have a formula, there really isn't any system that maintains the same invariants and distribution curve when converting.

That being said, there are some ways you could try and 'convert' your score. For example, you could find people on lichess who have similar ratings to yours, and see if they are USCF rated. Also, playing in a couple OTB tournaments would be more than enough to give you an accurate sense of what your ELO rating is around.

Hope this helps!


When is a bishop preferred over a rook I've seen some moves from my chess engine (Houdini) when a rook was exchanged for a bishop.

Even though I still lose the game, I see a degrading value for chess engine.

Is it just because of bad calculation or something else??

These situations are very rare, but they do happen from time to time. An example is the following 1919 game between J.R. Capablanca (the future world champion) and F.D. Yates.

http://www.chessgames.com/perl/chessgame?gid=1055968

[FEN ""]
    [FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 b5 7. Bb3 d6 8. c3 Na5 9. Bc2 c5 10. d4 Qc7 11. Nbd2 Bg4 12. d5 g5 13. Nf1 h6 14. Ng3 Rd8 15. a4 b4 16. cxb4 cxb4 17. Bd3 Bc8 18. Be3 Ng4 19. Rc1 Qb8 20. Bd2 Qb6 21. Qe2 Nb3 22. Rc6 Qa5 23. Bxa6 Bd7 24. Bb5 Bxc6 25. Bxc6+ Kf8 26. Qc4 Nxd2 27. Nxd2 Qa7 28. Qe2 h5 29. Nf5 Bf6 30. Nc4 Qc5 31. b3 Nh6 32. Nxh6 Rxh6 33. Qe3 Rc8 34. Rc1 Bd8 35. Qxc5 dxc5 36. Nxe5 Ke7 37. Rxc5 f5 38. Rc4 Ba5 39. Bb5 Rxc4 40. Nxc4 Bc7 41. e5 Bb8 42. Ne3 Rh7 43. Nxf5+ Kf7 44. e6+ Kf6 45. e7 Rxe7 46. Nxe7 Kxe7 47. g3 Bc7 48. Kg2 Kd6 49. Be8 h4 50. Bf7 Ke5 51. Kh3 Bd8 52. Kg4 hxg3 53. fxg3 Kf6 54. Be6 Kg6 55. d6 Kf6 56. Bf5 Bb6 57. d7 Bd8 58. h4 gxh4 59. gxh4 Bc7 60. h5 Kg7 61. Be4 1-0

Black had what is called a "weak color complex" on the White squares. When White exchanged his rook for Black's white squared bishop, his white squares became very weak (because all his pawns were on Black squares. White was able to get his other pieces (a rook and knight) on white squares behind these pawns, and pick them off, while Black's pieces were bottled up on Black squares.


Stockfish: Engine suddenly changed the side? I asked this question in stockfishchess.org support but didn't get any response. So I'm trying to get some answers from you all.

My question:

Please find the output of communication with the engine here. (It has only 8 steps.) The last best move (bestmove c5d4 ponder f3d4) is not for white, but for black.

Am I doing something wrong here or has engine confused for some reason? Appreciate your help to understand.

Original question link:
http://support.stockfishchess.org/discussions/problems/8262-engine-suddenly-changed-the-side

The reason is very simple:

  position startpos moves e2e4 d7d6 d2d4 e7e6 g1f3 c8d7 f1d3 h7h6 e1g1 c7c5 f1e1 e8f8

This is invalid. The position before e8f8 is:

e8f8 is invalid because Black has a bishop on f8. Stockfish can't play the move, so it just skip it.

To Stockfish, the diagram position is the position it's thinking. The best move is ...cxd4.


White seems better. How could I have capitalized? [FEN ""]
[StartPly "25"]
1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 e6 5.Nc3 a6 6.Nxc6 bxc6 7.Be2 d5 8.O-O Qc7 9.f4 Bc5+ 10.Kh1 d4 11.Na4 Ba7 12.b3 Ne7 13.Bd3 O-O 14.Qh5 f5 15.Ba3 Rf6 16.Bxe7 Qxe7 17.Nb2 Rh6 18.Qe2 Bc5 19.Rf3 Bd6 20.Nc4 Bc5 21.Ne5 Qc7 22.Bc4 Kf8 23.exf5 exf5 24.Re1 Bd7

White seems better. How could I have capitalized?

In my opinion, White has a decisive advantage here. He has a better pawn structure and a safer king, and all of his pieces are splendidly centralized.

Black on the other hand has pieces scattered all over the place, his bishops are restricted (but well posted for defense), and his queen is a bit clumsy on c7 but can be repositioned to a better square in a few moves.

At first, I wanted to play 1. Rh3 to remove the only defender of the kingside Rh6. That turned into an endgame where my minimal advantage fizzled out.

But then I found a new way to attack by opening the center with 1. c3!. This catches Black unprepared for combat as his Ra8,Qc7 and Bd7 are poorly placed. Since the White pieces are faster, it should not take them too much time to*decisively reposition themselves.

After checking this extensively with the engine, I have confirmed my conclusions.

Since the number of lines is vast, they will not fit here if I try to just copy/paste them. Therefore I will supply illustrative lines from the engine's first analysis.

If you need more efficient demonstrations, I suggest running each line separately through the engine, or posting a new question with the sub-variation you have a problem with.

Without further delay, here are the lines:

[fen "r4k2/2qb2pp/p1p4r/2b1Np2/2Bp1P2/1P3R2/P1P1Q1PP/4R2K w - - 0 1"]

1.c3! dxc3 ( 1...Be8 2.cxd4 $18 ) 2.Rd3 Be8 ( 2... Be6 3.Bxe6 Rxe6 4.Rh3 h6 5.Qc4 Qe7 6.Rxc3 Bb4 7.Ng6+ Rxg6 8.Rxe7 Bxe7 9.h3 a5 10.Re3 Rf6 11.Re6 c5 12.Rxf6+ gxf6 &18 ) 3.Qc2 Ba7 ( 3... Rd8 4.Rxd8 Qxd8 5.Qxf5+ Qf6 6.Ng6+ Rxg6 7.Qxc5+ Qd6 8.Qf5+ Qf6 9.Qc8 Qe7 10.Rxe7 Kxe7 11.Qc7+ Bd7 12.Qe5+ Kd8 $18 ) ( 3... Rh5 4.Rh3 Qc8 5.Rxh5 Bxh5 6.Qxc3 Qd8 7.b4 Bd4 8.Qd3 Bxe5 9.Qxf5+ Qf6 10.Qxh5 g6 11.fxe5 gxh5 12.exf6 Rd8 $18 ) (3... Bb4 4.Rh3 Bg6 5.Rxh6 gxh6 6.a3 a5 7.axb4 axb4 8.Qf2 Qd6 9.Qb6 Re8 10.Qb7 c5 11.Qa7 h5 12.h3 c2 $18 ) (3... Ra7 4.Rh3 g6 5.Rxh6 Bb4 6.Rh3 Ba5 7.Qe2 Qe7 8.Qf2 c5 9.Nxg6+ Bxg6 10.Rxe7 Rxe7 11.Kg1 Rc7 12.Rd3 Re7 $18 ) ( 3... Ba3 4.Rh3 Qe7 5.Rxh6 gxh6 6.Qxc3 Qg7 7.b4 Bc1 8.Qd4 Ra7 9.Qd6+ Re7 10.Rxc1 h5 11.Re1 a5 12.Bf7 Bxf7 $18 ) (3...Rf6 4.Qxc3 a5 5.Qc2 Bb4 6.Red1 Ra7 7.Qf2 h6 8.Qe3 Be7 9.Re1 Qb7 10.Nd7+ Qxd7 11.Rxd7 Rxd7 12.Qe5 Bf7 $18 ) (3... Qc8 4.Nf3 Qb7 5.Ng5 Bd7 6.Rh3 Re8 7.Nxh7+ Rxh7 8.Rxe8+ Kxe8 9.Rxh7 Bd4 10.Rh8+ Ke7 11.Qe2+ Kd6 12.Rd8 c2 $18 ) 4.Rh3 Qd6 5.Rxh6 gxh6 6.h3 Kg7 7.Qxc3 Bd4 8.Qg3+ Bg6 9.Nf3 Bf6 10.a4 c5 11.Re6 Qd1+ 12.Kh2 h5 13.Nh4 Rf8 14.Rxa6 Qc1 $18

Hopefully this helped. If you have any questions or remarks leave a comment.

Best regards.


King's Indian move order Isn't 1. d4 Nf6 2. c4 d6 (Old Indian Defense) a more flexible move-order than 1. d4 Nf6 2. c4 g6 (King's Indian Defense)?

I don't see why any Black player who wants to play the King's Indian would avoid the former move order.

It's actually a less flexible move order. The bishop will go to g7 in either case, but now black can't go ...d5 in one go. Only play this if you want to put the bishop on e7 (the Old Indian Defense)


Web Interface for training by dragging and dropping pieces Is there any web chess interface that lets me handle chess pieces as I like ?
 I mean  it will allow me to drag and drop pieces wherever I want them to be on the chessboard and add as many pieces as I like on it. I don't want an engine. I need simply an interface on the web, or some simple html files that I will use on my laptop.
Thank you in advance for any suggestions

There's also the lichess board editor. It supports all the features you want, and will also let you get a computer analysis or play the position against the engine.


When moves are randomized, is there an inherent advantage to the player who goes first, or the player who goes second? Imagine we are pitting two automated players (bots) against each other, but instead of thoughtful moves made by the players, they make completely random choices. I realize that this is not really the point of playing chess, but it sets the groundwork for a theoretical chess question.
Is there an inherent advantage to the player who goes first, or the player who goes second?
'Inherent advantage' here means that the probability of one player winning is higher than the other, and that these randomized conditions don't account for how actual players would play. If such an advantage exists, it may be entirely wiped away by how humans play chess with each other. I want to emphasize that this question is not meant to generalize to either human or algorithmic play.
Update
I got the results back of 1000000 randomly-played games thanks to a small adjustment to itub's code. I've whipped up a basic plot to show the results.

But if you prefer the specific numbers, here's the printout:
Counter({'is_insufficient_material': 474230,
'can_claim_fifty_moves': 169123,
'can_claim_threefold_repetition': 149398,
'1-0': 75868,
'0-1': 75239,
'is_stalemate': 56142})

As promised in the comments on one of the answers, I was going to calculate a Wilson score interval with continuity correction. I wrote the following function in Python to accomplish that.
import numpy as np
from scipy import stats

def wilson_cont(n1, n2, alpha=0.05):
    '''
    Wilson score interval with continuity correction.
    Two-tail interval is assumed.

    Parameters:
        n1 (int): Count of outcome 1.
        n2 (int): Count of outcome 2.
        alpha (float):

    Source:
        https://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval
    '''
    assert type(n1) == int and type(n2) == int
    assert 0 < alpha < 1
    z = stats.norm.ppf(1 - alpha / 2)
    n = n1 + n2
    phat = n1 / n
    num1 = 2 * n * phat + z**2
    num2 = z * np.sqrt(z**2 - 1 / n + 4 * n * phat * (1 - phat) + 4 * phat - 2) + 1
    num3 = z * np.sqrt(z**2 + 1 / n + 4 * n * phat * (1 - phat) - 4 * phat - 2) + 1
    denom = 2 * (n + z **2)
    return max(0, (num1 - num2) / denom), min(1, (num1 + num3) / denom)

And calling this function on the outcome counts where either white or black win, we have:
>>> print(wilson_cont(75868, 75239))
(0.4995569815292355, 0.5046054923932771)

This result, confirming some of the comments and answers below, is not significantly different from 50 %. As MaxW has pointed out in their answer, a similar calculation has been done on an even bigger sample that concluded that there was a statistically significant difference. One concern I have with all these calculations, mine and others, is that they become more sensitive to deviations as the sample size becomes larger. This means it is difficult to determine whether there's truly a difference using standard null hypothesis testing when our sample size becomes extremely large, but if we don't sample enough then our sample won't be representative enough. What this has illuminated to me is a form of conditional reasoning that if there is a difference, then it is extremely small in terms of effect size.
My thanks to everyone who has shown interest in this post, and contributed their reasoning, research, or code into it.

I once wrote a program to make random moves, had it play 1000 games, and these were my results:

Outcome                        Count  Avg. #moves
-----------------------------  -----  -----------
Draw by insufficient material    500          179
Draw by fifty-move               157          208
Draw by threefold repetition     147          164
Black wins by checkmate           75           87
White wins by checkmate           72           78
Draw by stalemate                 49          138

The sample is too small to reach a firm conclusion, but as you can see, Black actually won more games than White! (I think that was just luck.) More noticeable, though, is that the overwhelming majority of games are draws.

My hunch is that there is neither White nor Black have any advantage when making random moves. The oft-quoted first-move advantage of White is based on the notion that White has the initiative, but it is very easy to lose the initiative, and if you make random moves you are pretty much guaranteed to lose it very quickly. (Edit: thanks to MaxW's answer, I'm pleased to see that someone actually went through the trouble of simulating billions of games and found that actually White does have a very slight, but statistically significant advantage: 7.7340% vs 7.7293%).

I originally posted the table above as an answer to a different question: Of all the possible legal chess games, how many end in white win, draw and black win (assuming 50 move rule)? That answer goes into more speculation about why most games are draws, but more importantly has the Python source code in case it helps run your own simulations.


Which chess courses should I start with? I know the rules and played with my friends but without any knowledge of opening tactics etc. And all material I could find online was not in an ordered manner . So can you suggest some courses I can enroll myself online which cover the basics going all the way to the advanced level ?( I am an absolute beginner)

P.S.: Free resources would be more appreciable because I am just a student . Thanks

The Elo rating system is quite simple in an essence, and functions as such:
By beating a higher rated player, you accumulate more Elo rating points than if you were to beat a lower rated player. (Elo rating points basically measure your chess aptitude).

As for the other aspects that you have mentioned, I would recommend that you visit chess.com and lichess.com.


Is the following position a fortress? [FEN "8/4k2p/p1b1p1pP/Pp1p2K1/1PpP1P2/2P1R3/8/8 b - - 0 1"]

Houdini6.02 eval flatlines at 1.37, but I reached d= 54 , and , although the eval continued to flatline, the main line indicated White pushed the f4 pawn in f5 toward the end. I started a trial with the pawn already in f5 , Black to move, and White won. Still I am not sure because Houdini 6.02 could have missed a possible defense against the f5 push. Can Black defend against the f5 push without deteriorating the position ( maybe allowing the White rook to penetrate its position)? Or the position is a win for White , albeit slowly? Just for curiosity , if the verdict is draw , can White win in absence of the 50 move rule?

The key to tackling these kind of positions in a game is to imagine where you would like to put your pieces and then see how you could achieve that.
In this position for white the first aim would be to get the king to e5 to attack the e6 weakness and at the same time threaten to infiltrate on either f6 or d6. The problem is that black will have no problem defending the e6 weakness and defending the infiltration by keeping the king on e7 meanwhile shuffling the bishop.
Another weakness will be required to make progress. As it happens there is also no way of getting the king to e5 while the f pawn is on f4 so any plan will have to start with sacrificing the f4 pawn.
If it were white to move then the immediate f5 would force open the g file, a second weakness. Black would have to accept the sacrifice and ef would expose the black king to check from the rook so gf is forced. Then there is no way for black to both prevent the rook penetrating on the g file and prevent the king from infiltrating via f6 or d6. One line could go like this:
[fen "8/4k2p/p1b1p1pP/Pp1p2K1/1PpP1P2/2P1R3/8/8 w - - 0 1"]

1. f5 gxf5 2. Kf4 Be8 (2...Kf6 3. Rg3 {and black can't prevent the rook coming to g7 next move}) 3. Rg3 Bg6 4. Ke5 {Black is in zugzwang. Either the white rook is going to penetrate on the g file or the king is going to infiltrate on f6 or d6}

So, black's first task is to stop this simple plan. The only way to do that is with Kf7 which unpins the e pawn and allows the recapture ef. The problem for white with this is that it gets rid of the weak e6 pawn and replaces it with a weak d5 pawn.
The now open e file is nothing like as good as the open g file because of the white pawn on h6. The only way for black to defend an open g file is to block the file with the bishop on g6 but for the open e file all black needs to do is to cover the entry squares of e6, e7, e8 which can be done either by the king on f7 or a combination of the king on f6 and the bishop on c6. The weak d5 pawn can be protected by the bishop on either c6 or b7 and the white king can be prevented from infiltrating via e5 by the black king on f6.
If white could both threaten to infiltrate with the king to e5 and threaten to take the d5 pawn with the rook then a zugzwang could be possible but unfortunately the only way for the rook to threaten the d5 pawn is from e5 and if the rook is on e5 then the white king can't go to e5. Hence this position is a fortress.
This is what the lines would look like:
[fen "8/4k2p/p1b1p1pP/Pp1p2K1/1PpP1P2/2P1R3/8/8 b - - 0 1"]

1...Kf7 2. f5 exf5 3. Re5 Bb7 4. Kf4 (4. Re1 Bc6 5. Re2 Bd7 6. Kf4 Kf6) Bc6 5. Re1 Kf6 6. Re2 Bd7 7. Re5 Bc6

Going back to the initial position is there anything white can do to prepare the f5 push to make it work? Or, to put it another way, what must black do to stop f5 from working. The answer is that black must keep the king on f7, ready to both defend the e file if it opens and to play kf6 if white threatens to play Ke5. At the same time black's bishop must defend the d5 pawn from either c6 or b7 whenever the white rook is on e5 and it must defend the e8 entry square from d7 or c6 whenever the rook is not on e5.


Crazyhouse/Bughouse openings Are there any known or "standard" openings in bughouse or crazyhouse chess? Obviously, as soon as pieces start coming off the board things get less predictable, so this question is less about the existence of opening lines as it is about moves which are consistently seen to be good; e.g. White playing e4 to open development lines, or Black avoiding g6, which creates exploitable weaknesses.

I play 1... Nf6 after 1. e4.  Then 2. e5 d5 3. exf6 exf6.  I have had great scores with this opening versus Chess master.

[FEN ""]

1. e4 Nf6 2. e5 d5 3. exf6 exf6

The idea is to have strong king side with 4 pawns for defence. The second advantage is the development. Bishop in c8 is ready for attacks. If white castle king side u can put pawn in h3 if gh3, Bh3 or @Nf3+.


Dynamic (not-drawish) response for black against the c3 Sicilian Basically what the title suggests. Many of the responses to the c3 sicilian (1.e4 c5 2.c3) that I find online result in very drawish positions usually with queens off the board and very little dynamic play. I want lots of action and craziness while still being sound.

This is currently my favored variation (but this is still quite drawish and doesn't feel very 'Sicilian-y'): 1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 Nf6 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6.

Here are variations that I've tried:

1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 cxd4 5.cxd4 Nc6 6.Nf3 Nf6 (this goes on to be kinda passive for black and mostly boring).
1.e4 c5 2.c3 Nf6 3.e5 Nd5, which almost is awesome except it becomes really drawish after 4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6.

  Any ideas?

[fen ""]

1.e4 c5 2.c3 d5 (2...Nf6 3.e5 Nd5 4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6) 3.exd5 Qxd5 4.d4 Nf6 (4...cxd4 5.cxd4 Nc6 6.Nf3 Nf6) 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6

The line with Nf6 is actually pretty interesting. I think you overlooked the main line which is 6...c4, not 6...g6. For the record, the delayed d4 is the less popular variation. It leads to unbalanced play:

[fen ""]
1. e4 c5 2. c3 Nf6 3. e5 Nd5 4. Bc4 Nb6 5. Bb3 Nc6 6. Nf3 c4 7. Bc2 Qc7 8. Qe2 g5 9. e6 dxe6 10. Nxg5 Qe5 11. d4 cxd3 12. Bxd3 Qxe2+ 13. Bxe2 h6 14. Ne4 e5

There are of course other sidelines in this variation, with a major alternative being 9. h3 for white, but I encourage you to look into it some more.


Are there any chances that the Fischer who reappeared in 1992 was not the real one? As in title above, are there any chances that the Fischer who reappeared in 1992 (and then later on), was not the real Bobby? If this is not the case, what do you consider as "proof" that he was indeed the real Fischer?

At the very least we know that in 1992 a man that looked and sounded like an aged version of Bobby Fischer played Boris Spassky in a match, and won it. Assuming that this old man was actually not Fischer, we must think of plausible alternatives for who it possibly could've been. What old man besides Bobby Fischer will look like Bobby Fischer and be able to play well enough to beat a former world champion? How couldn't this mysterious veteran be at least somewhat famous in the chess world (being a strong player that is also a Fischer look-alike)? And how did he manage to dupe the chess world (including all the people who knew him on a personal level) into thinking that he was Bobby Fischer?

It is very difficult to give plausible answers to the above questions, and since there is no real indication that it wasn't the real Bobby Fischer to played Spassky I will go ahead and use Occham's razor to conclude that the most reasonable explanation is that it was the real Fischer that played in the 1992 match.


What happened to the WCC? Just found this rating list below while looking for other items.
I vaguely remember hearing about WCC.
What happened to them? All I find now for WCC is 'world chess championship'.
Apparently they both rated top players.

Combined Top 100 - January 1999 FIDE and WCC Chess Rating Lists
Note: The 1999 FIDE World Chess rating came late and contained errors. This is the fourth and presumably the final version of the FIDE top 100 list.
UPDATE: The Combined rating lists for July 1999 are posted at http://www.gmchess.spb.ru/ratings/july99.html

Rank    Name                    Country FIDE Rating Name                WCC Rating
1       Kasparov, Gary          RUS     2812        Kasparov, Garry     2803
2       Anand, Viswanathan      IND     2781        Anand, Viswanathan  2750
3       Kramnik, Vladimir       RUS     2751        Kramnik, Vladimir   2724
4       Shirov, Alexei          ESP     2726        Shirov, Alexei      2712
5       Morozevich, Alexander   RUS     2723        Kamsky, Gata        2701
6       Adams, Michael          ENG     2716        Leko, Peter         2693
...........

The WCC was the "World Chess Council".

It was formed in 1998 by Kasparov after the collapse of the PCA (Professional Chess Association) in 1995. It was Kasparov's fourth attempt at an organization separate from FIDE.

It organized the candidates match between Kramnik and Shirov in 1998, which Shirov surprisingly won (5.5-3.5), and he was slated to play Kasparov for the title. The match never happened since the organization collapsed during the negotiations when the organization lost its sponsors, and folded.

The best detailing of the events of that time that I have found can be found here. (Note that this outstanding site has many more pages of history, so click the "next" and "previous" buttons at the bottom to read more. I would love to just cut-and-paste it, but it is copyrighted material, so you will have to go visit the site.)

You can also find a little information here.


Rearrange chess diagrams (from an opening) in order. Useful as a puzzle? Here is an example https://chess-tst.000webhostapp.com/chess.html

The task is to rearrange the diagrams in order (use drag&drop).

Do you think this activity could be useful for exploring and revision of chess tabias at the beginner\pre-intermediate level? As a part of opening preparation.

Nice fresh idea! I would not use it exclusively for opening training, but whatever works for your target group. Could be fun for younger players I guess. A few problems I see with this approach:

When doing the exercise I was basically only looking for small changes from the previous diagram. I mean, for me it did not matter at all that I was looking at a chess board. It could as well have been a series of paintings (with incremental changes) or anything else. If people solve it the same way as I did, I doubt that they get much out of the puzzle for chess.
I found looking through nine diagrams already quite time consuming, so I guess getting very deep (say 20 moves) is not very pracical.
Including side lines seems impossible unless you create a puzzle for each side line, however in that case you would lose the connection between them (i.e. that at move x you have options a, b and c...).
IMO, beginner players should focus on learning general opening principles, the reason behind making those moves and typical plans in certain pawn structures. Your approach seems to train learning lines by heart, which I don't find useful, because they'd be lost immediately once they are out of book.

Perhaps puzzles like these could be more useful for tactics or for basic endgames!?

Or perhaps, for slightly advanced players, it could be useful to have something like this, not move-by-move, but only showing relevant positions (tabiyas) skipping over intermediate moves.


Which classic chess books are in the public domain? While looking through Project Gutenberg I noticed that Capablanca's Chess Fundamentals is there (I believe that should mean it is in the Public Domain). I was also able to find Modern Ideas in Chess  by Richard Rèti on line.

What other famous chess books are in the Public Domain and can be freely posted on a website? or how can I tell whether or not a book I own is in the public domain?

The International Chess Congress, St. Petersburg, 1909 is a classic by World Champion Emanuel Lasker was written in 1910 and is in the public domain.

[EDIT] ISBN: 1888690097, can be viewed online or downloaded in PDF at http://archive.org/details/internationalche00lask


Can Black always choose seating position and clock position? Watching tournament and competitive club play, players playing black sometimes switch the clock to their dominant side before the game starts without asking.

Presumably, having the clock on your dominant side compensates slightly for losing the first-move advantage because it makes it easier to operate the clock for you, it makes it harder for your opponent if they have the same dominant side as you, and it may serve as a small psychological crutch — particularly during blitz games.

But FIDE’s Laws of Chess state that:

  6.4
  Before the start of the game the arbiter decides where the chess clock is placed.

Additionally, I’ve seen Black switching the board around before either player has sat down so that they get the view of the room they prefer. IM Jeremy Silman even gives this tip in his “Psychology” section of The Complete Book of Chess Strategy:

  If you’re playing outdoors, don’t forget to face your opponent towards the sun (it worked five hundred years ago and it will still work today)!

Which must be a reference to this quip:

  Sit your opponent with the sun in his eyes.
  — Ruy Lopez, 1561

Two questions:

As black, will I get in trouble for moving the clock before the game without asking?
As black, is it an acceptable practise to ask to trade seats?

Answers can refer to casual play, club play, and tournament play.

It is an interesting question, but you already gave the answer. It is the arbiters decision where the players sit and the clocks are placed (so that the arbiter can see them best). When no official arbiter is present, the team captain of the home team acts as arbiter. These rules are for tournaments and club matches. Casual is of course different.
If a player does not follow the arbiters decision he can get penalized (eg. time reduction, which happened few months ago at our club match, because of the exact same clock positioning question)


Was this a valid draw? I was playing this game in-person with someone and I was white. My opponent had a pawn on a7 and kept moving his king back and forth  between c6 and d6 at least 3-4 times while I maneuvered my bishop around the board to capture his pawn on a7 to make room for my past pawn. After I captured his pawn on a7 he moved his king back to d6 and claimed it was a draw because at that time he had moved his king back and forth on the same 2 squares 6 times. I understand the 3 fold repetition but his king had other squares to move and wasn't in a perpetual check. Was this a valid draw?

No, it was not a draw. For a draw by three-fold repetition, the exact position, and all of the possible moves (castling and en passant, which since en passant can only happen on the move, in essence, it requires a fourth repetition of the position), have to be repeated three times.

It was clearly a case of your opponent not really knowing the rules.

It seems like he was somewhat confusing, and mixing, three-fold repetition with the 50-move rule, which requires 50 moves of just moving around without a pawn move or capture with repeating the position three times.

P.S. The repetitions do not need to be consecutive.


A good site to learn Anki for chess openings? Can someone tell me a good website in order to learn to use Anki for chess opening improvement?

Anki is a program for spaced repetition. You can use it to train chess without being online at all.

Chesstempo is a site on which you can train chess and it also allows you to use spaced repetition.


What are the letters and numbers next to an opening's name on online services? Here, it shows "C22": [Name of opening]. This is from an online service, and I was confused what this is. At first, I thought it was for the specific sites database, but I have seen the letters and numbers used with the opening name on chess.stackexchange.com too. What is it?

The Encyclopedia of Chess Openings (or ECO) is a classification system for the opening moves in chess.

Instead of the traditional names for the openings, ECO has developed a coding system that has also been adopted by other chess publications. There are five main categories, "A" to "E", each of which is divided into 100 subcategories.

Here is more info and related questions in case you are interested:

How are the ECO codes for chess openings assigned?

https://en.wikipedia.org/wiki/Encyclopaedia_of_Chess_Openings

Does ECO openings classification have an established more detailed specification - by sub indexes?

And this is the exact same code that you mentioned, covered in another source:

https://www.365chess.com/eco/C22_Centre_game_Berger_variation


Library to program mini games In Corona times, it is not so easy to train children over the board. When that was possible, we used a lot of mini games with fewer pieces and most of the times a different goal. To bring those mini games online is not so easy, due to many factors:

Known chess libraries like chess.js (the most used Javascript library for chess) only allows standard games and does not support mini games.
Chess online sites like lichess.org have their set of games possible, and it is not at all easy to expand that.
Children should have a very simple web interface to start a game, play it, ...

So I am thinking about creating something myself. I am sure I can come up with a simple web application to register, pair players, ..., but the hardest part (for me) is to check that the rules of chess are met. But this set of rules is not fixed. Here are some examples

Some mini games don't have kings at all. This is not allowed in standard chess.
Some mini games treat the kings like normal pieces, so there is no chess, or even kings can be beaten.
Some mini games define the end of the game when the first piece is beaten. Or a pawn is promoted.
One variant I know has as rule that knight moves as knight, but captures as bishop, and vice versae.
Some mini games are played on different sized boards.
Some place pieces, that are not allowed to moved and / or captured.

What I am looking for is a library (preferred Javascript) that allows to add easily additional rules, and define for each game which rules are mandatory. Do you have recommendations about this?

Fairy-Stockfish supports configuration of chess variants at runtime, and it also has bindings for Python (pyffish) and Javascript (ffishjs) which can be used as libraries for chess variant game logic. E.g., PyChess has very few game logic built in, and uses both bindings in backend and frontend for the variant rules.
If you do not want to build something on your own, ChessCraft might be an alternative to be able to define and play variants directly in a UI.


What is so great about Bxa3? I only have about 35 games experience , so please excuse blunders.
I am in the following position. My app (dr wolf) wants me to capture on a3. However I fail to see either the extreme threat posed by the enemy Knight, or the extreme utility of the enemy vacating the b column, that would justify sacrifice (corr.: exchange) of my bishop.
[FEN "r1bqkbnr/ppp2ppp/2n5/4p3/3p4/N1PP1N2/PP1BPPPP/R2QKB1R b KQkq - 0 1"]

Can anyone explain the strengths of this move?

Black wrecks white's pawn structure

Black gains in development since he's trading an undeveloped piece for a developed one.

Although the center is sill fluid, black's dark square bishop is currently a "bad" bishop. in the short run, white's knight is the more active piece.

It removes the support of the c-pawn which opens up some tactical possibilities and also forces white to do something in the center rather than sitting back.


Best opening in blind simultaneous chess I am interested in blind simultaneous chess, where one person plays (blind) vs multiple (non-blind) opponents.

What would be the best openings for either side? I would assume anything slow would be disadvantageous to the blind person.

Generally, the simul-giver needs to keep the games as different from each other as possible. That means the opening themselves are less important, as long as they are different openings.

The simul-takers can cooperate with each other; I recall the following story from Tim Krabbé's website:

  It made me think of a story. A grandmaster once played a 10-board blind simul somewhere. Knowing the ropes of blind simuls, he varied his games right from the start, maybe opening two with 1.e4, two with 1.d4, one with 1.b3, and so on. To his suprise, all of his opponents played 1...b6. On the second move, five of them played 2...Bb7, and the other five 2...Ba6. On the third, three of the five players who had played 2...Bb7 now played 3...Bc8 and the other two played 3...Ba6, while three of the five who had played 2...Ba6 now played 3...Bb7, and the other two 3...Bc8. On move 4, the grandmaster saw bishops everywhere. After move 5, he excused himself and went to the toilet where he was happy to find a window big enough to let him through.

  I would assume anything slow would be disadvantageous to the blind person.

That makes sense, because there are more pieces on the board. However, if those pieces occupy 'normal' positions, that's usually easier to remember/visualize (from my personal experience, which is limited to a single blindfold game at a time). So if you're taking part in a blindfold simul, and don't want to 'cheat' like in the above story, play a 'weird' opening.


How to know when it is time to trade down to an endgame? Sirs,

After considerable endgame study (i.e. Jeremy Silman's complete endgame course), I am finding that there is a wealth of information about how to win endgames.  However, I am noticing that there isn't as much information about knowing/judging when it is time to "trade down" to an endgame.

I'm not at all confused by the most basic principles such as "trade down to an endgame when you are a knight-ahead or better".  However, I would love to see an outline (or a link to some kind of equivalent knowledge) addressing more detailed situations such as:

--a.)  trading down to an endgame when white has two passed pawns on opposite sides of the board vs. black's poorly guarded pawn on the 7th rank.

--b.)  win/lose/draw analysis of bishop only endgames when bishop are of same color, or Knight vs. bishop endgame success?
etc, etc.

Does anyone know of a website, book, or resource addressing this niche subject of judging whether or not to trade down to an endgame?

Regards,

Brent

The reason there isn't much information on when to trade down when there isn't a large material advantage is because it is obvious.

If you have a small advantage but you calculate that trading down will leave you with an endgame which you know how to win then trade down. Note that even if you are bishop and knight up (say something like KQBN v KQ) and can trade down to a KBN v K endgame and you know that theoretically it is winning for you but you don't know how to win then there is no point in trading down because it is very easy for the defender to last 50 moves and claim the draw against someone who lacks the knowledge. Try and win some other way while there is more material on the board.

Similarly if you are a pawn or two down but have the chance to trade down to an opposite coloured bishop endgame where you know because of your endgame knowledge that your opponent's extra pawn(s) are not going to be enough for him because you know how to draw that position then trade down.

The difficult part is having the endgame knowledge in the first place.

If you reach a position where you are trying to decide whether to trade down or not but don't know, it is not because nobody has given you the magic answer. It is because you lack the endgame knowledge to judge the final position after the trade down.


1. e4 e6 2. Nc3 - how should Black respond? I had White deviate from the French main line in a blitz game by playing:

[FEN ""]
1. e4 e6 2. Nc3

Since this line is not discussed in the Wikipedia article on French defence I am thinking that Black may have better options than to simply pursue normal French development with:

[FEN ""]
[StartPly "3"]

1. e4 e6 2. Nc3 d5

(which is what I played, it being a blitz game and all)

I was thinking maybe it's worthwhile to respond with:
2...Bb4
with the aim of a Bishop-Knight exchange and forcing White to suffer double pawns on the c-file.
Or try the non-committing: 2...Nf6 or 2...Nc6.

The chess engine XBoard / Fairy-Max 4.8Q with 50 minutes available time for Black (for 40 moves) suggested 2...Be7.

Any thoughts?

Well, let's start by looking at the position

[FEN ""]
1.e4 e6 2.Nc3

Why does white play 2.Nc3? Because white gets two options after the standard (!) 2...d5, namely 3.d4 or 3.Nf3 as shown below

[FEN ""]
1.e4 e6 2.Nc3 d5 3.d4 (3.Nf3)

In case black wants to aim for a French system position, I would say that 2...d5 is the best option. In case black wants to go for other types of positions, then it is possible to go for a Sicilian system with 2...c5 as well as more independent routes like 2...Bb4, 2...e5. It is also possible to go for some sort of hybrid after 2...Be7 3.Nf3 g5 4.h3 h5, as shown below. What is the objectively best move? Well, I would say that 2...c5 and 2...d5 are equally strong. While 2...Bb4 seems like an interesting option that needs a bit more research. Or just try it for fun and see where it goes!

[FEN ""]
1.e4 e6 2.Nc3 d5 (2...c5) (2...Bb4) (2...e5 3.Nf3 Nc6 4.Bb5 Nd4) (2...Be7 3.Nf3 g5 4.h3 h5)


Of all the possible legal chess games, how many end in white win, draw and black win (assuming 50 move rule)? If both sides make moves completely randomly but legally, how many different games are there? Since the 50 move rule applies, this number should be finite (but HUGE).

For example, there are 20 possible first moves for white to start with. If we include the first move for black, there will be 400 different positions.

Among all these different games, how many of them will be win for white? Black? Draw?

I guess very few (in term of percentage) game will end with a draw. And the winning percentage will be roughly the same for white and for black.

The number of games is huge but finite, and estimates have been made based on a number of assumptions. But that question has been asked before already, so I won't go into the details here. A short answer given on Wikipedia is at least 10123, based on an average branching factor (moves per position) of 35 and an average game length of 80; after only 10 plies (5 full moves) the exact count is 69,352,859,712,417. See Is the number of possible chess games infinite? for more answers.

The probable outcomes of a game with random moves can be estimated "experimentally" by running random simulations. I wrote a program to do just that, had it play 1000 games, and these were my results:

Outcome                        Count  Avg. #moves
-----------------------------  -----  -----------
Draw by insufficient material    500          179
Draw by fifty-move               157          208
Draw by threefold repetition     147          164
Black wins by checkmate           75           87
White wins by checkmate           72           78
Draw by stalemate                 49          138

I think that the most common result is a draw because random moves are rather incompetent at mating, which requires the interaction of at least three pieces (counting both colors, including kings), in contrast with capturing, which is much easier to do by chance, only requiring the interaction between two pieces. After enough captures occur, you end up with insufficient material, which is the most likely outcome, occurring 50% of the time.

Alternatively, if you don't luck into a capture for long enough, you are also somewhat likely to bump into the fifty-move limit or threefold repetition. (My program assumes that these draws are claimed as soon as possible, even though they are not automatic per the rules, unlike 75-move or fivefold repetition.)

I don't expect a color advantage in random games. My sample had a few more wins with Black than with White, but I think that's within statistical noise.

For anyone who is interested, here's my program, written in Python and using the python-chess module:

import chess
import collections
import random

terminations = ['is_stalemate', 'is_insufficient_material', 'is_checkmate',
    'can_claim_fifty_moves', 'can_claim_threefold_repetition']

def get_termination(board):
    for termination in terminations:
        method = getattr(board, termination)
        if method():
            return termination

def game():
    board = chess.Board()
    for i in range(10000):
        moves = list(board.legal_moves)
        move = random.choice(moves)
        board.push(move)
        result = board.result(claim_draw=True)
        if result != '*':
            termination = get_termination(board)
            print(result, board.fullmove_number, termination)
            return result, termination

stats = collections.Counter()
for i in range(1000):
    result, termination = game()
    if termination == 'is_checkmate':
        stats[result] += 1
    else:
        stats[termination] += 1

print(stats)


Does an out of turn draw offer constitute an actionable distraction / time penalty? I was playing in a sudden death time control last night with less than 5 seconds left and while thinking about my moves with literally 2 or 3 seconds remaining, my opponent blurted out a draw offer. Startled by this, I blundered and lost the game.

My understanding is that draw offers must be made when the OFFERER's clock is running and that offering a draw or making other statements to an opponent when they are thinking is a distraction and is not allowed.

Would I have been within my rights to stop the clock and demand from the TD that 2 minutes be added to my clock because of the distraction?

The game was played under USCF rules and was in sudden death with seconds remaining for both players.

According to my copy of US Chess Federation's Official Rules of Chess (5th Edition), rule 14B2 states:

  If a player offers a draw while the opponent's clock is running, the
  opponent may accept or reject the offer.  A player who offers a draw
  in this manner may be warned or penalized for annoying the opponent (20G).

Note that it says "may", not "must".  Rule 20G says that the director has discretion to say whether there was a violation and what the penalty, if any, should be.  So you could request, but you could not "demand", that the time be added.

Rule 1C2a says that two minutes added to your clock is the standard penalty if one is imposed.  1C2b, however, explicitly states that the director can vary from this.

Rule 21F says you indeed have the right to stop the clock to ask for a ruling from the director.  And you must do it right away; you ordinarily waive your rights if you don't notify the director promptly.


Anand - Carlsen Game 1 WCh 2014, why not 12.Qc3+? In game 1 of the World Championship 2014 between Carlsen and Anand, Anand chose 12.gxf3. Why not play 12.Qc3+ instead? It takes control over the a1-h8 diagonal and prevents the black Nc6 to jump to d4 or e5. In addition, it gives white the option to grab on f3 with the queen, keeping the pawn structure on the kingside intact.

[FEN ""]
[Event "WCh 2014"]
[Site "Sochi RUS"]
[Date "2014.11.08"]
[Round "1"]
[White "Anand, Viswanathan"]
[Black "Carlsen, Magnus"]
[Result "1/2-1/2"]
[Eventdate "2014.11.08"]

1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.Bd2 Bg7 6.e4 Nxc3 7.Bxc3 O-O 8.Qd2 Nc6 9.Nf3 Bg4 10.d5 Bxf3 11.Bxg7 Kxg7 12.Qc3+

[FEN ""]
                [Event "WCh 2014"]
                [Site "Sochi RUS"]
                [Date "2014.11.08"]
                [Round "1"]
                [White "Anand, Viswanathan"]
                [Black "Carlsen, Magnus"]
                [Result "1/2-1/2"]
                [Eventdate "2014.11.08"]

                1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.Bd2 Bg7 6.e4 Nxc3 7.Bxc3 O-O 8.Qd2 Nc6 9.Nf3 Bg4 10.d5 Bxf3 11.Bxg7 Kxg7 12.Qc3+ e5 (13.dxc6 Be4 14. Qe5 f6 15. Qc3 Re8 16. Be2 Bxc6)
    (13.gxf3 Nd4 )
   (13.Qxf3 Nd4 )
   (13.dxe6 Qf6 14. Qxf6 Kxf6 15. gxf3 fxe6)

Computer Houdini 1.5a w32 suggests 13... e5
Now four options for white 13.dc 13.de ep, 13.gf or 13.Qf3 anything else loses a piece.

After 13. dc black replies 13... Be4 and white cannot take pawn on e5. If 14. Qe5 then 14... f6 15. Qc3 (15 Qe4 loses a queen). 15... Re8 this forces white reply  16. Be2 and black just takes on c6 16.... Bc6 , this is a win for black.

13.gxf6 black moves its knight to the centre 13... Nd4 Knight on d4 cannot be moved. Pawn on f3 is weak. Black is better.

13.Qf3 Again same idea – black’s knight occupies the centre Nd4 and whatever white answer is black threatens to crush the white centre 14... c6. Again black is better (maybe not as good as after 13. gf)

13.dxe6 e.p. black needs to cover the diagonal – 13... Qf6 or 13... Qd4 anything else consolidates white’s position in the centre.
13...Qf6 14 Qf6 (otherwise black takes on c3) 14... Kf6 (forced) 15 gf (forced) 15... fe again black is better (weakness on f3)
13...Qd4 white cannot take on d4, so 14. e7 (if 14. gf black takes on c3 and again weakness on f3 is giving black an advantage)  14... Re8 15. gf again cannot take on d4. And now either 15...Re7 or 15... Qc3 and black has better pawn structure.


Are online USCF tournaments worth playing? I play a lot on ICC, and I notice they offer a few days of rated blitz and other time controls.

I'd like to play more rated games, however I'm afraid of how easy it is to cheat online. It seems like there is nothing stopping someone from having a laptop with them and making moves by running the game through stockfish. They could screw up just enough to evade "bot behavior" detection.

Are these types of games worth playing at all? Or should I just stick to going to the club once a week for classic games?

First of all, the vast majority of people are not cheating.  If they were, 1200 would be a master rating, and it's not.

Second, in a USCF rated game, you're not anonymous.  The games are connected to your real name and your USCF membership.  There might be some people willing to cheat anonymously who would be less willing if it could be traced back to them personally, and possibly put their offline membership at risk, rather than simply forcing them to make a new online account.

Third... yes, some people cheat.  If you do play against Stockfish (with or without added mistakes) once or twice, so what?  It won't be most of the time.

Fourth, if you're worried about cheaters affecting your rating, it appears that online play currently only affects your USCF "Blitz" rating, not your "Regular" USCF rating.

In summary:  If you think it would otherwise be a good idea, there's no reason to let the prospect of cheaters dissuade you.  (Although skipping club to play online would just be silly in most cases.)


About solving Atomic Chess Is it possible to weakly solve Atomic Chess as a win for White? I've analysed a few lines good for White, but I am not sure about a general solution.

As a decently strong atomic player fairly connected with the atomic community including the strongest players, I feel I can answer this one. The short answer is: white probably wins, but there is no weak solution nor does it currently seem achievable to find one.

Outcome?
The current consensus among the strongest players and opening theoreticians is that White wins, but as of yet there is no public and/or convincing and exhaustive proof. Opinions differ on whether many different openings and lines are winning or drawn; however there tends to be agreement that the lines after 1. Nf3 f6 2. Nc3 Nh6 3. g4 (the first tabiyas in this rabbit hole would be after 3...c6 4. d4 e6 5. e4 f5 6. Nh4 or exf5 with many sideline branches on black's 2nd, 4th and 5th moves) give no hope for black if white plays perfectly (and by "perfectly", that tends to be 20+ move deep, widely branching theory in complicated middlegames, leading to nontrivial endgames). That said, from a practical point of view, these are also not easy to meet as black at high levels.
This, however, does not constitute a weak solution. We do not have an exhaustive (or even very aggressively pruned) game tree that leads to white wins everywhere. All we have is a lot of opening theory where both sides play sensible moves and where with precise play by white, just about everything leads to what seem to be winning white endgames. The branching factor for plausible moves appears to be too high for a weak solution to be within reach, though -- in addition, the endpoint endgames themselves may not be easy to evaluate for humans, and not for engines either.

A word on engines
The modern engine for atomic analysis is Stockfish 9, but using the 2018 or earlier builds, as more recent builds seem to give pruning issues leading to outright blunders and misevaluations in certain cases. Other engines exist like Atomkraft (an older engine), and offer different but also strong opinions.
A major shortfall of atomic engines in general, though, is their endgame knowledge is poor. One commonly-occurring situation is a pawn endgame where one side is up a whole bishop, yet cannot win because the bishop cannot take an enemy pawn, nor can passed pawns be created. This is known as "pawnitisation" (common enough to have a name since more than a decade ago!) and engines cannot detect this reliably, often giving a +3 to +4 evaluation to draws. They also, due to the horizon effect, tend to misevaluate simple endgames where one side is up two pawns for minor (yes, up) with rooks on the board, which is winning in general but can take many moves.
While 6-man tablebases exist for atomic, these do not solve the problem; many of these endgames have more than six units on the board.
This leads to the issue that engines, despite being stronger than humans (still not completely invincible though!), may not be fully relied on to accurately evaluate a position.

Conclusion
An engine-only "solution" of atomic would be met by skepticism due to their inability to accurately judge a fair number of endgames. In fact, even an engine-assisted weak solution would seem unattainable, also because of the high branching factor of plausible moves, and high depths (think at least 40+, probably more than 60+) needed for reliability.


What's the best chess tactics trainer on the web? There are plenty of chess tactics trainers out there on the internet. What trainer works best for you? Why?

chesstempo.com.
free
tactics gets harder as your tactics rating increases
can play standard or blitz tactics (rating adjustment dependent on time took or independent)


White fights for equality in French classical? Normally, using engines for any given opening I can find ways for White to maintain a slight edge into the middle game. By a "slight edge" I mean an evaluation of around +0.20

The exception to this is the Classical French (and Steinitz), where it seems like every line Black has at least equality and most lines lead to an edge for Black!

For example, in his book on the French, Psakhis says that after 1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. Bg5 Be7 5. e5 Nfd7 6. h4 0-0?! is dubious for Black after 7. Bd3. However, the engine shows that not only is not dubious for Black, but Black has the advantage after 7...c5!

This is just one example. No matter what line I try, Black always seems to get at least equality.

Even more scary is that not only is Black always getting equality, but White seems to have a lot more ways to go wrong than Black in many of the lines.

Is there any line in the Classical where White can retain a pull?

I am using Komodo 10 as my engine.

An evaluation of +0.2 is just noise and nothing like a "slight edge". Another engine might very well give you -0.2 or so. I would not be overly concerned by such evaluation.

When analyzing opening lines, much more important is the character of the position: whether you like it, whether it  gives you winning or drawing chances (depending on requirement), whether it is easy to play for you (and difficult for your opponent), etc. All of these are difficult to assess automatically with a computer and require you to look at it. That's why GM spend so much time on openings and don't just have their computers running looking for the line with the highest evaluation.


In a KP-K endgame, if the enemy king is in front of the pawn, is it always a draw? In a KP-K endgame, if the enemy king is in front of the pawn, is it always a draw?

I've tried it in various positions, yet my opponent always is able to get in front somehow and promote the pawn.

I hear it's always always a draw. I've  been playing for so many years, and never figured out how to get the draw. What is the correct technique to do this that always works?

If the king is on the sixth and the pawn is on the fifth (and it's not a rook pawn), then it's a win for the side with the pawn, no matter who has the move:

[FEN "4k3/8/4K3/4P3/8/8/8/8 w - - 0 1"]

1. Kd6 Kd8 2. e6 Ke8 3. e7 Kf7 4. Kd7 Kf6 5. e8=Q *

With Black to move:

[FEN "4k3/8/4K3/4P3/8/8/8/8 b - - 0 1"]

1... Kd8 2. Kf7 Kd7 3. e6+ Kd8 4. e7+ Kd7 5. e8=Q+ *

If you back it up, though, the position is a win with Black to move and a draw with White to move. If White has to move first, Black can simply mirror the movements of the White king until White moves the pawn forward.

[FEN "8/3k4/8/3K4/3P4/8/8/8 w - - 0 1"]

If the pawn is in front of the king, the general strategy is to make sure to oppose the enemy king when it goes alongside its pawn, to prevent it from getting in front.

[FEN "4k3/8/4P3/4K3/8/8/8/8 w - - 0 1"]

1. Kd6 Kd8 2. Ke5 Ke7 3. Kf5 Ke8 (3... Kf8?? {This loses! If you take this critical square too soon, before the enemy king is alongside the pawn, you can't stay on the square when the enemy king does advance.} 4. Kf6 Ke8 5. e7 Kd7 6. Kf7) 4. Kf6 Kf8 5. e7+ Ke8 6. Ke6 {Stalemate.} 1/2-1/2


What is the average speed in tournaments for USFC rapid chess ratings? Rapid ratings cover a very wide range of time controls and bump up against regular (where games are dual rated) as well as blitz time controls.

What is the average time for USCF rapid games that are rated in USCF tournaments?

Comments on the validity of the extremes are also welcome.

But in practice what is the average encountered in all or most tournaments? Or even a distribution for high endish , low endish, middling value? And which of those is prevalent?

This page will let you see every tournament that was rated in a particular state in a particular month. It takes a little effort from there to click through and see what the time controls were for each tournament. Going through all of them is too much for me, but I decided to take a couple of sample states. Looking at every quick rated tournament in December 2019 and January 2020 in Wisconsin, the time controls were:

G60 d5 (7 events)
G45 d5 (2 events)
G30 d5
G26 d3 (3 events)
G25 +4

So, if you add the increment/delay to the time, half were 65 minute games (the maximum allowable for dual-rated games) and 4 out of the other 7 were 29 minute games (the maximum allowable for quick-rated-only games). The average was about 50.4 minutes.

Now let's look at a larger state. Florida had the following quick rated tournaments in December 2019:

G60 d5
G55 d5
G50 d5
G45 round 1 G60 rounds 2-3
G40 +10
G40 d5 (4 events)
G30 d5 (4 events)
G25 +10
G25 d5 (10 events)
G24 d5
G20 d5 (3 events)
G15 d5

As was the case with Wisconsin, most of these were dual rated events; games well below 30 minutes were rare. But in Florida, it seems that 30 minute games (the minimum allowable for dual-rated) were the most common. The 65 or 29 minute games that were the most common in Wisconsin were rare here; only one of each of those were played. The average was about 36.5 minutes.

If you combine the two states, then the time controls were as follows:

Time  Number of tournaments
65    8
60    1
55    1
50    4
45    4
35    6
30    10
29    5
25    3
20    1

It would seem, then, that which time controls are popular depends on your area. But in both states, there tended to be many tournaments right at the edge of where the events would be dual rated, at 65 or 30/29 minutes. The average was about 41 minutes, and the median was 35. There weren't many tournaments that were towards the low end of what can be quick rated.


Is it possible to get a professional degree in chess? I am a software engineer by profession, and a chess enthusiast (around 1600 rated).
I would like to know is there any professional university certified course like Masters etc. in chess?

Can someone opt for Chess as a means of getting Ph.D or do some research in it?

You can tell me answers like becoming titled players is the same as that, but i am talking about academic university level course.

Is yes, it is there? Can someone post me a link to that?

There are a couple that come to mind, but I am not sure of the present status of them:

Texas Tech has SPICE (Susan Polgar Institute for Chess Excellence) founded by Susan Polgar and is the first chess institute of it's kind in the world.

Aberdeen University in Scotland was preparing to launch the world's first doctoral program in Chess.

As far as research goes, you can research anything you want about chess, but keep in mind that one normally does not research chess alone, but researches things build up to chess.  By things, I might mean certain data structures or algorithms that are found in chess software.  Other avenues of research can be explored besides the technical part of it as well.

Equating a chess title to a degree title is too subjective.


What does "penned in" mean in Chess? Bishops are worth more than knights except when they are penned in.

What is meant by penned in? Does that mean that they are blocked by other pieces?

I believe Brian Towers and user58697 are correct, and the author wrote/meant pen instead of pin. The dictionary tells it's a small enclosure for animals, or an abbreviation for penitentiary, which seems more appropriate. Still, it's the first time I encounter this word in a chess setting, so it's not common and the confusion is understandable.

While @Bad_Bishop provides the general (and, AFAIK, only common) use of the term pin in chess, I believe the author of your quote meant something along the lines of

  Bishops are worth more than knights except when they are blocked by their own pawns.

(which matches your thoughts on the subject). Ironically, those bishops are often called bad bishops, like the white one in the diagram below:

[FEN "8/5pp1/3bp2p/1p1p4/1P1P4/2B1P2P/5PP1/8 w - - 0 1"]

One could argue that all pieces (including rooks and queens) have the same value when pinned (as in the common use of the word), but this is not entirely true; a pinned piece still prevents the opposing king from moving to certain fields, and a pinned bishop covers more squares than a pinned knight.


Queen with Knight capabilities I find it interesting that the Queen can move with the same capabilities as the Rook and the Bishop, but cannot 'jump' or move like the Knight, I understand that this would overpower the queen but theoretically could make the game more interesting, quicker, or more strategic.

I want to know, what are the practical implications of giving the Queen this extra move-set?

Are there any obscure chess variations where this is allowed?

Are there any obscure chess variations where this is allowed?

There are. One name for the queen+knight hybrid piece is the Amazon. As noted in the Wikipedia entry on the Amazon piece I just linked to, the Amazon appears in the variant sometimes called Turkish Great Chess, a game played on a 10x10 board and featuring besides the Amazon (which is typically called a Giraffe in Turkish Great Chess) two other fairy chess pieces: a bishop+knight piece (Vizir) and a rook+knight piece (War Machine). (Those sorts of pieces appear under yet different names in the Capablanca Chess and Seirawan Chess variants as well.)

A second variant that is mentioned in the Amazon Wikipedia entry is The Maharaja and the Sepoys, which provides a severe test for the might of the Amazon: namely, it pits a lone Amazon (Maharaja) against a standard chess army on an 8x8 board. An Amazon is capable of checkmating a king by itself, and that is its objective, while the standard army is tasked with checkmating the very mobile Amazon.


Could Ding win this endgame vs Carlsen? Could Ding win this endgame vs. Carlsen (at this point in the diagram), in the game played yesterday at Lindores Abbey? Without using engines, it seems logical to me to play 41.Re3 or 41.Rd3 (instead of 41.Kc5 as played by Ding), with the idea of leaving the f2 Pawn to its destiny, but clearing a way for the King to the g6 Pawn, and eventually winning Black's other Pawns, while the White Rook is defending the g3 Pawn.

[fen "8/1k6/6p1/3K1p1p/1P5P/5RP1/4rP2/8 w - h6 0 1"]

This is a book draw. At our level it is difficult but at GM level this is an easy version of KR+3 v KR+4 with the extra pawn on the the queenside. The fact that Black's king is already in position to block the passer makes it much easier than the classic version of this endgame. His very active rook is another plus. White is not going to lose but he can make at best token efforts to win.

  Without using engines, it seems logical to me to play 41.Re3 or 41.Rd3
  (instead of 41.Kc5 as played by Ding)

These moves make no sense. Black is then going to play Rxf2 and follow up with f4. Soon the kingside pawns will be eliminated and the draw becomes much easier.

Jonathan Rowson devotes 42 pages to this endgame in his book "Amateur to IM". If you want to find out more about this endgame then his book is highly recommended.


The Art of the Checkmate, Quiz 24: Is there a win? This is quiz 24 from The Art of the Checkmate by Renaud & Kahn.

Black to play and win

rn3rk1/pp3ppp/3b1n2/2pPq3/2B1P3/1NN2bP1/PPPQ1P1P/R1B2RK1 b - - 0 1

The authors give this as the winning line:

   1... Qh5 2. Be2 (as Black was threatening Qh3-g2#) Ng4 (threatening mate on h2) 3. h4 Qxh4 4. gxh4 Bh2#

However, I think White has a simple refutation:

   2. Re1 prepares Bf1, stopping the Qh3-g2 threat, and Ng4 threats can be nullified with h4, as the Queen sacrifice doesn't work now as the King has a flight square

So, my questions are:

Is there a forced win (mate or material)?
If so, what is it?
If not, what's the best move?

Yes, you're right, there is no forced win. With correct play, White avoids the mate, and Black can only win one of the two pawns he is currently behind. White will have a healthy pawn more with best play from both sides:

rn3rk1/pp3ppp/3b1n2/2pPq3/2B1P3/1NN2bP1/PPPQ1P1P/R1B2RK1 b - - 0 1

1... Qh5 2. Re1 Ng4 3. h4 Ne5 4. Bf1 Bxe4


How can I know the Elo rating of my chess engine? I built an uci compatible chess engine, and I would like to know its Elo rating. What is the easiest way to get it?

I would like something that works both on Linux and Windows.

Easy question. Announce your engine on the chess programming forum (http://talkchess.com/forum/index.php). There'll be engine testers adding your engine to their rating list, such as CCRL. But please and please provide a working compiled binary.

Announce your engine, upload a compiled binary to somewhere like Dropbox. You'll hear feedback.

EDIT

cutechess is a popular tool for automating computer engine-to-engine matches. The only and only way to test your changes is to make your engine to play games. You can make it to play with an older version or another engine.

https://chessprogramming.wikispaces.com/Cutechess-cli


Can it be useful for a player block with a hanging piece in a back rank mate situation? Could the following situation possibly exist?

It's White to play, and Black is about to get back rank mated. This is because the King's mobility is restricted to a single file. Then White gives a check.

At this point, Black plays the best move that blocks with a hanging piece, where the blocking piece has no defense. White takes the piece with check, and black can now escape somehow.

An example of this is that by blocking check with a hanging knight, Black opens up a bishop's path to further block, but this time safely and checkmate is avoided.

[FEN "R5k1/5ppp/8/2r5/1b6/8/5PPP/6K1 b - - 0 1"]

1... Rc8 2. Rxc8+ Bf8

This is an example of what Tim Krabbé calls an 'unguarded guard' - a linepiece checks, and a piece interposes on an unguarded square. That page mentions Topalov - Polgar, Novgorod 1996 (see below); while not a true back rank mate, it comes close. Here are some endgame studies with other types of Unguarded Guards.

[FEN ""]
[Event "Novgorod"]
[Date "1996-07-27"]
[White "Veselin Topalov"]
[Black "Judit Polgar"]
[StartPly "92"]

1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 Nc6 5.Nc3 Qc7 6.Be3 a6 7.Bd3
b5 8.Nxc6 Qxc6 9.O-O Bb7 10.a3 Nf6 11.Re1 Be7 12.Qf3 d6 13.Qh3
h5 14.Bg5 Qc5 15.Be3 Qc6 16.f3 g5 17.a4 b4 18.Na2 g4 19.fxg4
d5 20.c3 bxc3 21.bxc3 Nxg4 22.Bd4 Bc5 23.Be2 Nf6 24.e5 Ne4
25.Nb4 Bxd4+ 26.cxd4 Qb6 27.Nc2 Rc8 28.Rab1 Qa7 29.Bd3 Rg8
30.a5 Bc6 31.Rb6 Bb5 32.Bxe4 dxe4 33.Rxe6+ Kf8 34.Qa3+ Kg7
35.Re7 Rc7 36.Rxc7 Qxc7 37.Ne3 Kh8 38.Rc1 Qd8 39.d5 Qg5 40.Qc3
Kh7 41.Qd4 Bd3 42.d6 h4 43.Rc7 Rb8 44.Rxf7+ Kg8 45.e6 Qxe3+
46.Qxe3 Rb1+ 47.Qc1 Rxc1+ 48.Kf2 Rc6 49.Rd7 Bb5 50.Ke3 Rc2
51.Rc7 Re2+ 52.Kf4 Rf2+ 53.Kxe4 Re2+ 54.Kf5 Rf2+ 55.Ke5 Re2+
56.Kf6 Rf2+ 57.Ke7 Re2 58.d7 Bxd7 59.Kxd7 Rd2+ 60.Ke8 1-0