Pi-R-Squared spaceship: Difference between revisions
MathAndCode (talk | contribs) m Mentioned the commonness of the components |
Sorry, but there is perhaps a more appropriate example |
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{{Glossary}} | {{Glossary}} | ||
The '''Pi-R-Squared spaceship''' is a fictituous [[spaceship]] due to [[Dave Greene]], supposedly consisting of two [[pi grandparent]]s and two [[R-pentomino]]s, with a population of 20 in a 55×34 [[bounding box]], moving at speed [[c]]/137. | The '''Pi-R-Squared spaceship''' is a fictituous [[spaceship]] due to [[Dave Greene]], supposedly consisting of two [[pi grandparent]]s and two [[R-pentomino]]s, with a population of 20 in a 55×34 [[bounding box]], moving at [[speed]] [[c]]/137. | ||
It was claimed to have been "seen briefly in 1974 on a PDP-12 display by Tony Honcho Jarnow" (an anagram of "[[John Horton Conway]]"), arising from the [[ash]] of a random 128×80 [[soup]], "just before an unfortunate power outage due to tripping on a power cable".<ref name="post57860" /> | It was claimed to have been "seen briefly in 1974 on a PDP-12 display by Tony Honcho Jarnow" (an anagram of "[[John Horton Conway]]"), arising from the [[ash]] of a random 128×80 [[soup]], "just before an unfortunate power outage due to tripping on a power cable".<ref name="post57860" /> | ||
The idea is that the R-pentomino and the five-cell pi grandparent are each fairly common and therefore likely to pop up in general, regardless of what the pattern was like dozens or hundreds of generations earlier (as long as it had not already adopted a stable/repeating configuration). If one of the many initial patterns that could lead to this also had two R-pentominos and two pi grandparents (in the same configuration), then that would result in a spaceship. In | The idea is that the R-pentomino and the five-cell pi grandparent are each fairly [[common]] and therefore likely to pop up in general, regardless of what the pattern was like dozens or hundreds of generations earlier (as long as it had not already adopted a stable/repeating configuration). If one of the many initial patterns that could lead to this also had two R-pentominos and two pi grandparents (in the same configuration), then that would result in a spaceship. In August {{year|2013}}, [[Martin Grant]] discovered a near-miss spaceship that relies on a similar principle, where an R-pentomino descendant moves at a speed of 14c/65o with a dot [[spark]].<ref name="post8872" /> In December {{year|2020}}, [[Tanner Jacobi]] found a mechanism where two blocks and two traffic light predecessors, aided by a line of gutter symmetry, happen to form from the same arrangement 61 generations earlier plus one dot spark on each side due to their sheer commonness.<ref name="post116246" /> | ||
==References== | ==References== | ||
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|title = Re: Thread for basic questions | |title = Re: Thread for basic questions | ||
|date = March 13, 2018 | |date = March 13, 2018 | ||
|author = Dave Greene | |author = Dave Greene | ||
}}</ref> | |||
<ref name="post8872">{{LinkForumThread | |||
|p = 8872 | |||
|format = ref | |||
|title = Re: Thread For Your Accidental Discoveries | |||
|date = August 27, 2013 | |||
|author = Martin Grant | |||
}}</ref> | |||
<ref name="post116246">{{LinkForumThread | |||
|format = ref | |||
|title = Re: Thread For Your Useless Discoveries | |||
|p = 116246 | |||
|author = Tanner Jacobi | |||
|date = December 17, 2020 | |||
}}</ref> | }}</ref> | ||
</references> | </references> | ||
[[Category:Jokes]] | [[Category:Jokes]] | ||
Revision as of 10:35, 23 December 2020
The Pi-R-Squared spaceship is a fictituous spaceship due to Dave Greene, supposedly consisting of two pi grandparents and two R-pentominos, with a population of 20 in a 55×34 bounding box, moving at speed c/137.
It was claimed to have been "seen briefly in 1974 on a PDP-12 display by Tony Honcho Jarnow" (an anagram of "John Horton Conway"), arising from the ash of a random 128×80 soup, "just before an unfortunate power outage due to tripping on a power cable".[1]
The idea is that the R-pentomino and the five-cell pi grandparent are each fairly common and therefore likely to pop up in general, regardless of what the pattern was like dozens or hundreds of generations earlier (as long as it had not already adopted a stable/repeating configuration). If one of the many initial patterns that could lead to this also had two R-pentominos and two pi grandparents (in the same configuration), then that would result in a spaceship. In August 2013, Martin Grant discovered a near-miss spaceship that relies on a similar principle, where an R-pentomino descendant moves at a speed of 14c/65o with a dot spark.[2] In December 2020, Tanner Jacobi found a mechanism where two blocks and two traffic light predecessors, aided by a line of gutter symmetry, happen to form from the same arrangement 61 generations earlier plus one dot spark on each side due to their sheer commonness.[3]
References
- ↑ Dave Greene (March 13, 2018). Re: Thread for basic questions (discussion thread) at the ConwayLife.com forums
- ↑ Martin Grant (August 27, 2013). Re: Thread For Your Accidental Discoveries (discussion thread) at the ConwayLife.com forums
- ↑ Tanner Jacobi (December 17, 2020). Re: Thread For Your Useless Discoveries (discussion thread) at the ConwayLife.com forums