Two squares a move. The other player collapses.
X 0, O 0, draws 0
A simplified variant: the earlier classical line takes the whole point. It does not use Goff's half-point scoring.
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Uses of quantum tic tac toe
- Passing one phone across a table when the rules are easy to argue
- Playing a full match without creating an account
- Seeing which squares a move linked before anyone calls a win
- Taking back a collapse that the other player wants to reconsider
quantum tic tac toe pitfalls
- Marking one square and expecting a classical X or O
- Treating a spooky three in a row as a win
- Closing a cycle and then choosing the collapse yourself
- Refreshing mid-match and expecting the score to still be there
quantum tic tac toe questions (6)
What is a move in quantum tic tac toe?
A move marks two different squares with the same number. X1 is the first move. Those two squares stay linked until a cycle collapses.
Who chooses the collapse?
The player who did not close the cycle. Both resolutions are listed. That player picks one, and the choice is its own step.
Does a spooky three in a row win?
No. Only a classical line wins. Letters that still share squares are entangled. They do not score.
What if both players get a line from one collapse?
The earlier line takes the point. The line whose highest move number is smaller wins. The later line does not take a half point. This page plays a simplified variant and does not use Goff's half-point scoring.
Can I mark a square that already collapsed?
No. A classical square takes no further mark. The note says that square already has a classical mark, and the turn stays put.
Does undo restore the links?
Yes. Undo takes back one ply. Undoing a collapse puts the links and the two choices back. The score follows that ply.