Relay

A relay is an oscillator in which spaceships (typically gliders) travel in a loop. The simplest example is the p60 glider shuttle shown below using two pentadecathlons. Pulling the pentadecathlons further apart allows any period of the form 60 + 120n to be achieved. This is the simplest proof of the existence of oscillators of arbitrarily large period.

x = 35, y = 7, rule = B3/S23 2bo4bo$2ob4ob2o$2bo4bo$16bo$17b2o8bo4bo$16b2o7b2ob4ob2o$27bo4bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ WIDTH 800 THUMBSIZE 2 ZOOM 18 GPS 5 AUTOSTART ]]

pentadecathlon relay (p60 glider shuttle) (click above to open LifeViewer) RLE: here Plaintext: here

Table of adjustable relays

Note that for a glider relay supporting periods of the form c₁+c₀*n, if the following conditions are met:

• gliders are reflected 180º between two ends without offsetting their lane,
• the oscillating components at its ends (when the gliders are removed) have a period divisible by 2 but not 4 (such as unices in the p42 glider shuttle),

then using two copies of the relay, whose gliders reflect off each other in a rephaser, to provide a set of oscillators of the form c₂+c₀*n, where c₂ ≡ c₁ + c₀2 (mod c₀)

relay	periods	population
Buckaroo loop	30 + 120*n	51
p60 glider shuttle	60 + 120*n	29
6 bits	75 + 120*n	49
106P135	135 + 120*n	106
Metamorphosis II	60 + 360*n	150
Gallus (34P7 version)	42 + 56*n	105
Ocellus	90 + 24*n	92
Silverstream	90 + 120*n	106
p42 glider shuttle	42 + 24*n	143
p50 glider shuttle	50 + 40*n	188 if n = 0 else 183
p43 Snark loop	43 + n	228
p49 bouncer loop (using the 74-cell variant of the p7 pipsquirter) (1 glider)	140 + 56*n	365
(2 gliders)	70 + 28*n	370
(4 gliders)	35 + 14*n	380
(5 gliders)	28 + 56*n	385

See also

• Relays (category)
• Shuttle

External links

• Relay at the Life Lexicon