Phi spark
| Phi spark | |||||||||
| View static image | |||||||||
| Pattern type | Spark | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Number of cells | 10 | ||||||||
| Bounding box | 5 × 4 | ||||||||
| Static symmetry | Unspecified | ||||||||
| Discovered by | Unknown | ||||||||
| Year of discovery | 1970 | ||||||||
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A phi spark is a common, large symmetric spark that dies in 9 generations. It gains its name from resemblance of its generation 1 to a capital letter phi (ɸ).
Sparker oscillators which produce phi sparks are called phi-sparkers and are of considerable importance due to the several uses of the spark. The pentadecathlon, which splits into two phi sparks during its cycle for a span of five generations before their central halves regenerate the oscillator, is the most commonly used. Tanner's p46 is another notable high-clearance phi sparker.
The phi spark has the same symmetry as the line-of-six spark, a visually similar spark which follows a comparable evolution sequence.
Occurrence and evolution
Phi sparks are a rather common sight in the evolution of soups, being produced during the evolution of the well-known Herschel.
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A phi spark. |
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Generation 1 reveals the origin of the name. |
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A triangle is a common parent of the phi spark. |
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A 7-cell pattern arising from a Herschel, which becomes a phi spark in 8 generations (a triangle in 7). |
The majority of phi sparks have a triangle as a parent. Other parents do exist; the second most common parent is displayed below. A 2×5 rectangle also becomes a phi spark, but its natural occurrence is uncommon.
| Another phi spark parent (click above to open LifeViewer) |
Uses
The bi-block reaction seen in several oscillators involves a bi-block being perturbed such that it would evolve into a phi spark. The triangular parent is then also sparked, causing it to revert to a bi-block in the exact same location.
Interactions with gliders
Phi sparks can interact with gliders in several ways, with reflections being one of the most commonly utilised such interactions.
| (click above to open LifeViewer) RLE: here Plaintext: here |
Turning into a glider
A phi spark plus an instant V-spark can create a glider.
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In addition to the p46 gun, period LCM(56,32)=224 and LCM(63,72)=504 guns have been made this way, although they are not the smallest of their period. [1] If both sparks are provided by oscillators, the periods must not be coprime.
As an induction coil
Some natural period-2 oscillators have generation 0 of the phi spark with the three-cell leading edge on each side stabilized by various objects. The center oscillates with period 2 in a similar manner to a spark coil or test tube baby.
| An example of the paragraph above (click above to open LifeViewer) |
See also
References
- ↑ hotdogPi (May 9, 2024). Re: Gun Discussion Thread (discussion thread) at the ConwayLife.com forums
External links
- Phi spark at the Life Lexicon



