3177: Chessboard Alignment

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Chessboard Alignment
Luckily, the range is limited by the fact that the square boundary lines follow great circles.
Title text: Luckily, the range is limited by the fact that the square boundary lines follow great circles.

    Explanation

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    The comic shows an overhead view of three chess boards side by side, with two players facing each other across most of the boards. Yellow squares (used to show the available or actual movement of a given piece) have been marked leading from the starting position of the middle board's right bishop (F1) to the upper-right. The path continues beyond the edge of the middle board, across four columns of empty space or unseen table, and ends in the top left corner (A8) of the right board. The right board has only one rook (black rectangle) while the other two boards each have two, so it is implied that the bishop has captured the rook. The text below jokingly claims that if you align chess boards exactly, pieces can cross the boundary like this. This is not legal in normal chess [citation needed], but fits into Randall's long history of comics about unusual chess rules or boards.

    The title text refers to the fact that chess boards are normally placed approximately level (parallel to the surface of the Earth). A perfect line of chessboards placed end to end on the surface of an Earth-sized sphere (or on perfectly placed tables on that sphere) would form a "great circle" - the longest possible path around that sphere. While nearby boards would appear to be in the same plane, the curvature of the earth would cause boards more distant than 3.57 meters away to be in planes so different that the squares would be more than a micrometer off from the ideal straight lines leading off the board. It is thus implied that each infinite-range piece's valid path is a straight line of virtual squares that eventually leads into space. Otherwise, the alleged rule would allow chess moves between boards that were kilometers (or even whole countries) apart in any vertical line. If following the great circle along the ground was considered a straight line, then it would also be possible for each side's rooks and queen to capture their counterparts in the other color's back row, just by moving backwards around the planet. This does not rule out motion to another board on another celestial body or spaceship, though delivery of a chess piece across this distance would be impractical. This is thus the second comic in a week about distances extending past typical boundaries.

    Transcript

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    It doesn't happen often because it requires micrometer precision, but if two chess boards are perfectly aligned, it's actually legal to move pieces between them.


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    Discussion

    ...Honestly, kinda don't get this one... --DollarStoreBa'alConverse 02:27, 6 December 2025 (UTC)

    ohhhhhh... --DollarStoreBa'alConverse 02:28, 6 December 2025 (UTC)

    wait how do comments workAvrayter (talk) 02:52, 6 December 2025 (UTC)

    I don’t understand what the title text is saying. Can someone explain it to me? Logalex8369 (talk) 03:05, 6 December 2025 (UTC)

    when I read the title, I thought of D&D Alignment, and now I want one 93.36.184.70 07:31, 6 December 2025 (UTC)

    Chess Notation?

    I think a funnier title text would've been: Bfi8(!!!) Fephisto (talk) 06:22, 6 December 2025 (UTC)

    Modern physics?

    I suspect allusions to modern physics. The exact alignment of chess boards reminds me of the exactness needed to build laser resonators. The chess piece hopping from one board to another reminds me of quantum tunneling. The title text reminds me of light following geodetic lines in general relativity. There might be a specific quantum effect that is meant here, but I don't know. 195.52.146.164 06:29, 6 December 2025 (UTC)

    For anyone wondering: This is not legal, because even though "The bishop may move to any square along a diagonal on which it stands" FIDE defines a diagonal as "A straight line of squares of the same colour, running from one edge of the board to an adjacent edge", meaning it always ends on the edge. 85.76.137.112 07:29, 6 December 2025 (UTC)

    Moving from one board to another reminds me of a variety of chess variants. You know the ones: bughouse chess, Alice chess, 5D Chess With Multiverse Time Travel. (I'm still trying to find a way to get Randall to try out that last one.) ISaveXKCDpapers (talk) 10:01, 6 December 2025 (UTC)

    Math of great circles

    Not sure how to express well mathematics of great circles, to make it clear, that it is not just longitudal lines but in any direction really. I fixed the basics, but right now it still says something potentially misleading.--Trimutius (talk) 14:36, 6 December 2025 (UTC)

    Category

    Should this comic go in Category:Comics_with_color? --175.34.54.104 11:33, 6 December 2025 (UTC)

    The game position

    I think in white's position, the only moves that could prevent ...Nd5# are Qa4+, Qxd4, and various moves to e2. I don't hold out much hope for white. To me, this says the bishop move is a desperate attempt by the bishop to survive a bit longer. It made a king sacrifice. --Divad27182 (talk) 13:54, 6 December 2025 (UTC)

    My impression (without trying to recreate the exact play-by-play that got there) is that middle-white's defence 'exploded', they (forced or unforced) sent up to six pawns forward, losing three, dramatically unshielding the King in a very unsafe manner and (through exposure to the black Queen, later assisted by the Knight to plug potential movements) was left with no choice other than to advance white-King out there to get out of various checks.
    But I'm intrigued by the 'rules', of pieces escaping to the other board. Does middle-white play in turn with middle-black, but may (as their turn) move middle-white pieces around the right board without regard (either way) of the right-white/right-black turn-taking? The asynchrony (could pepper right-board movement with timely movements ahead and/or behind right-white's turn, to support them against right-black with additional 'intersticial' moves (until middle-black, or even left-black, opts to move pieces over there as well). Or act as strictly' "second move for white"? What happens when MW's King is mated (as it surely will, especially if MW is opting to move off-board pieces rather than fight the 'local' game)? Their pieces are taken away? Inherited? Continue to 'double-tap' their moves alongside the native player of the board? They're now entirely unfettered by MB's move to which they now don't need to wait to respond?
    Alternatively, it's a piece given to Right-White (until, perhaps, RW moves it, like any other piece, back into MW's game in their own play-order). There could be an exodus of MW pieces (bishops, rooks, queen only, with the right position opportunities; assuming you can't move to mid-board positions two or more times to allow knights and king to eventually enter full 'exile'; a couple of pawns could make it across, with complicity of an opponent, but only if you can end and capture upon tween-board spaces), and left-board players could even decide to send rooks/queens to the right-board for a comicated melee of chess.
    And, however it happens, does this also apply for boards properly aligned (or diagonally-aligned) front-to-back (leapfrogging to other boards, unseen, in further rows of competition 'up/down' of this row-of-three). And, ignoring the strictly planar nature hinted at in the comic, an 'Earth Sandwich' of board and antipodal-board could be interesting... allowing a Queen (for example) to flow off this board in all eight directions to land on the other board (in some modes, arriving on the new board in the same direction as they left the first one... unless that's set up at right-angles... although it wouldn't bother a queen... could be troublesome if pawns are allowed to keep moving off-board, for as long as it takes, to arrive not necessarily on the respective home-row of the destination grid... or have them become obligate-backwards/sideways-advancing 'borrowed' pawns, if that's how the boards (mis-)align?).
    No matter what the governing body says about board-edges, I need to know more about the practical limits and opportunities to this obscure rule! 82.132.239.11 16:44, 6 December 2025 (UTC)
    The bishop knew their team was about to lose, so they decided to join another team’s play instead. Logalex8369 (talk) 16:51, 6 December 2025 (UTC)
    You'd have thought a bishop would have had more faith! 82.132.239.11 17:36, 6 December 2025 (UTC)
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