Difference between revisions of "3177: Chessboard Alignment"

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==Explanation==
 
==Explanation==
{{incomplete|This page was created BY EN PASSANT. Don't remove this notice too soon.}}
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{{incomplete|This page was created BY AN ALIGNED BISHOP. Don't remove this notice too soon.}}
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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.
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 +
The title text refers to the fact that chess boards are normally placed approximately level (parallel to the surface of the Earth). As such there are two different possible interpretations of the title text, whether you are following geodesics on the surface of the Earth (any great circle) or following the geodesics of spacetime (leaving the Earth and going into space).
 +
 
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The second board's position seems to have followed (up until before this cross-boards move) the game seen in [[3045: AlphaMove]].
 +
 
 +
;    Following great circles
 +
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 {{w|great circle}} - the longest possible path around that sphere, as well as only straight path on spheres. Rule would allow chess moves between boards that were kilometers (or even whole countries) apart in any direction, along {{w|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 [https://www.chessvariants.org/shape.dir/torus_standard_board.html Torus chess], but only for pieces that can move unlimited amount of squares. There is a caveat to it though, size of a square would have to divide the great circle exactly with a precision down to micrometer, so quite possibly only one direction would work if any at all, as Earth is not a perfect sphere, so distance around the Earth would differ in different directions. Notable exceptions being the South Pole and the North Pole where all great circles are the same, and while the North Pole is in the {{w|Arctic Ocean}} so you won't be able to stay level there easily, at the South Pole there is {{w|Amundsen–Scott South Pole Station}} where this variant of chess can be more interesting if you have correct size of the board squares, with both verticals and horizontals working.
 +
 
 +
When you have to pick a single direction that works for looping your own chessboard then there are three options of orienting the chessboard:
 +
* If you choose horizontal line, then you will get a limited variant of {{w|Cylinder chess}}, where only Queen and rooks can utilize the wrap around, and only when moving horizontally
 +
* If you choose vertical line, it is technically also a cylinder for rooks and queens, but it will create an interesting dynamic, where players would be able to exchange queens and rooks in first 2 turns, for example doing this opening: 1. Qxd8+ Kxd8 2. Rxh8 Rxa1
 +
* If you choose diagonal, then it basically will result in Queens and Bishops to be able to jump over all pieces (they cannot switch to a different diagonal, like it would happen in cylinder chess, as all diagonal will loop on itself), though they would have to have visibility of one of the edges of the chess board and also as they would emerge on the opposite side of the diagonal they cannot jam themselves in-between 2 or more pieces. Also most likely diagonal works only in one of the 2 possible directions too, so there is an extra choice there (unless you are at one of the Earth's poles, where you can make both diagonal directions work).
 +
 
 +
;    Following geodesics of spacetime
 +
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. Straight line would have to be in overall spacetime of the universe along a {{w|Geodesics in general relativity|geodesic}}, 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 {{w|geostationary orbit}}. Though if you want to be level with earth and 'aim' you chessboard at a geostationary satellite, because those orbits are so far away from the Earth, you would have to be at latitude of around 81.4° in either Arctic or Antarctic. So chess game would have to take place at some {{w|List of northernmost settlements|arctic research station}} ({{w|Station Nord, Greenland}} being the optimal) or somewhere on the continent of {{w|Antarctica}} (best research station there is {{w|Sobral Base}}, though not as good as Station Nord). If this interpretation is accepted then this can be considered a second comic in a week about [[3174: Bridge Clearance|distances extending past typical boundaries]].
  
 
==Transcript==
 
==Transcript==
 
{{incomplete transcript|Don't remove this notice too soon.}}
 
{{incomplete transcript|Don't remove this notice too soon.}}
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 +
:[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.<!-- which I won't describe, both for brevity and for possible misrecognition of the low-detail depiction of each piece-->]
 +
:[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.
  
 
{{comic discussion}}<noinclude>
 
{{comic discussion}}<noinclude>
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[[Category:Chess]]
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[[Category:Comics with color]]

Revision as of 19:19, 6 December 2025

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

Ambox warning blue construction.svg This is one of 53 incomplete explanations:
This page was created BY AN ALIGNED BISHOP. Don't remove this notice too soon. If you can fix this issue, edit the page!

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). As such there are two different possible interpretations of the title text, whether you are following geodesics on the surface of the Earth (any great circle) or following the geodesics of spacetime (leaving the Earth and going into space).

The second board's position seems to have followed (up until before this cross-boards move) the game seen in 3045: AlphaMove.

Following great circles

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, as well as only straight path on spheres. 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. There is a caveat to it though, size of a square would have to divide the great circle exactly with a precision down to micrometer, so quite possibly only one direction would work if any at all, as Earth is not a perfect sphere, so distance around the Earth would differ in different directions. Notable exceptions being the South Pole and the North Pole where all great circles are the same, and while the North Pole is in the Arctic Ocean so you won't be able to stay level there easily, at the South Pole there is Amundsen–Scott South Pole Station where this variant of chess can be more interesting if you have correct size of the board squares, with both verticals and horizontals working.

When you have to pick a single direction that works for looping your own chessboard then there are three options of orienting the chessboard:

  • If you choose horizontal line, then you will get a limited variant of Cylinder chess, where only Queen and rooks can utilize the wrap around, and only when moving horizontally
  • If you choose vertical line, it is technically also a cylinder for rooks and queens, but it will create an interesting dynamic, where players would be able to exchange queens and rooks in first 2 turns, for example doing this opening: 1. Qxd8+ Kxd8 2. Rxh8 Rxa1
  • If you choose diagonal, then it basically will result in Queens and Bishops to be able to jump over all pieces (they cannot switch to a different diagonal, like it would happen in cylinder chess, as all diagonal will loop on itself), though they would have to have visibility of one of the edges of the chess board and also as they would emerge on the opposite side of the diagonal they cannot jam themselves in-between 2 or more pieces. Also most likely diagonal works only in one of the 2 possible directions too, so there is an extra choice there (unless you are at one of the Earth's poles, where you can make both diagonal directions work).
Following geodesics of spacetime

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. Straight line would have to be in overall spacetime of the universe along a geodesic, 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. Though if you want to be level with earth and 'aim' you chessboard at a geostationary satellite, because those orbits are so far away from the Earth, you would have to be at latitude of around 81.4° in either Arctic or Antarctic. So chess game would have to take place at some arctic research station (Station Nord, Greenland being the optimal) or somewhere on the continent of Antarctica (best research station there is Sobral Base, though not as good as Station Nord). If this interpretation is accepted then this can be considered a second comic in a week about distances extending past typical boundaries.

Transcript

Ambox warning green construction.svg This is one of 28 incomplete transcripts:
Don't remove this notice too soon. If you can fix this issue, edit the page!
[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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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)

Did the math for 'aiming' at geostatinary satellite from while being level. https://www.wolframalpha.com/input?i=arccos%286371%2Fsqrt%2842%2C164%5E2%2B6371%5E2%29%29 . If anybody wants to check my math please do so.--Trimutius (talk) 19:06, 6 December 2025 (UTC)

Do you have to consider other boards to avoid castling through check? 2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E 20:19, 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)

I think this was my biggest edit on this wiki, but I think I managed to make a decent explanation of the math of how this works. Also split it off from the going into space variant.--Trimutius (talk) 18:14, 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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