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Chessboard Alignment

|< < Prev #3177 (December 5, 2025)

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

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Explanation

The comic shows an overhead view of three chess boards side by side, with an average of two players facing each other across 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, and the player who made the move is now apparently paying attention to (and plausibly co-playing with the neighbouring player on) the board he has moved his piece to. 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. Alternatively the alleged rule would allow chess moves between boards that were kilometers (or even whole countries) apart in any direction, along great circles of the Earth, as any straight line on any sphere or ellipsoid can be extended all the way across. If following the great circle along the ground was considered a straight line, then it would also be possible for each side's rooks, bishops and queen to capture their counterparts in the other color's back row, or in later game they would be able to teleport between left and right side, or jump on the other side of any diagonal for pieces that move diagonally, as it would be possible to go around planet following any horizontal, vertical or diagonal line of the chessboard, if no other chessboard were involved it would make it into Torus chess, but only for pieces that can move unlimited amount of squares. If instead straight line would have to be in overall spacetime of the universe, it would 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^{[citation needed]} and other objects in space would move so fast relatively to your board they would be in alignment only for fraction of a second, unless it is a satellite in a geostationary orbit. This can be considered a second comic in a week about distances extending past typical boundaries.

Transcript

[An aerial view of three chess-games, with six players shown, in each case with white at the near-side of board (towards the bottom of the comic panel) and each having reasonably developed game positions.]

[The middle board has yellow highlight on the squares from white's King's Bishop's original position, diagonally forward-right to the respective edge square of the board, then four more squares in the gap between boards until ending on the black Queen's Rook square of the right-hand board, which appears now to have three white bishops, one of them on this rook's starting square.

[There is just one black rook, elsewhere on the right board, whether or not the other was lost to middle-board's bishop, and the middle board has only one bishop (and is lacking three pawns, with just two others still in their starting positions), for white, with apparently their King sent forward-left by two successive diagonal moves but no other major pieces having noticably relocated.]

[The middle board's near-side player has now also moved across to pay attention to the right hand board, leaving only his opponent facing his original board.]

[Text below the main scene's panel:] 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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