Switch engine ping-pong is a quadratic growth pattern that was found by Michael Simkin on October 29, 2014.[1] In terms of its 23 cells it was formerly the smallest known quadratic growth pattern, superseding the previous record holder, 24-cell quadratic growth, also found by Simkin a week earlier, but having since been beaten out by 22-, 21-, and 20-cell patterns in 2022. The initial state of the pattern contains a pre-block and a glider headed towards an R-pentomino grandparent in the top-left corner, and a glider headed towards an R-pentomino in the bottom-right. The R-pentomino and glider interactions create two parallel switch engines headed to the top-right, and a middleweight spaceship which collides with them repeatedly to form switch engines headed to the bottom-right, leading to quadratic growth.
It is the first such pattern found that uses only 2 switch engines, and it shows that quadratic growth can be synthesized with no more than 7 gliders.[2]
Gallery
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Generation 40,210,710,958,656, viewed at a scale of 236:1.
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Generation 40,210,710,958,656, viewed at a scale of 213:1; zooming in on the left corner of the "solid triangle" reveals that it is in fact made up of branching "lines".
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Generation 40,210,710,958,656, viewed at a scale of 1:1; zooming in further on the leftmost "branching point" reveals the structure of the "lines".
References
External links
Generation 40,210,710,958,656, viewed at a scale of 236:1.
Generation 40,210,710,958,656, viewed at a scale of 213:1; zooming in on the left corner of the "solid triangle" reveals that it is in fact made up of branching "lines".
Generation 40,210,710,958,656, viewed at a scale of 1:1; zooming in further on the leftmost "branching point" reveals the structure of the "lines".
