DOWN

  Difficulty: Intermediate   Keywords: EndGame, Theory

For "Down" as a direction on the board see Up and down



In Combinatorial Game Theory DOWN is the name of an infinitesimal, also written ↓. DOWN is defined as

`` darr = { ast | 0 } ``

Left (Black) can play to `` ast `` (STAR), while Right (White) can play to ``0``. DOWN is negative, favoring Right, who gets the last play, no matter who goes first. The opposite of DOWN is UP, also written ↑.

Some plays with a miai value of 1 chill to DOWN. (See Chilled Go). Here is an example.

[Diagram]

1 + DOWN


This position chills to 1↓ (1 plus DOWN). White can get tedomari locally, no matter who plays first.



White to play can simply fill, of course, leaving no further play.

[Diagram]

STAR



If Black takes, we reach this position where either player has a 1-point move to end local play. (Except for a ko threat if White takes, which we ignore in chilled go.)

See also


This is a copy of the living page "DOWN" at Sensei's Library.
(OC) 2024 the Authors, published under the OpenContent License V1.0.
[Welcome to Sensei's Library!]
StartingPoints
ReferenceSection
About