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{{Glossary}}
{{Glossary}}
A '''fuse''' is a [[wick]] that burns at one end, possibly creating byproducts. A [[clean]] fuse is much to be desired, even one leaving no residue. The messier the debris, the harder it would be to combine it with something else.  
A '''fuse''' is a [[wick]] that [[burn]]s at one end, possibly creating byproducts. A [[clean]] fuse is much to be desired, even one leaving no residue. The messier the debris, the harder it would be to combine it with something else. Like [[pure glider generator]]s, fuses were of early academic interest in the 1970s and often reported in [[Lifeline]] issues, but nowadays fuses that are not [[reburnable]] have been found to be so numerous that new examples no longer receive much attention.


Like [[pure glider generator]]s, fuses were of early academic interest in the 1970s and often reported in [[Lifeline]] issues, but nowadays fuses that are not [[reburnable]] are no longer considered important.  
Fuse may also refer to a [[still life component]] consisting of a diagonal line of two or more [[live]] [[cell]]s. This article is about the first definition, above.
 
==Examples==


==Examples==
Various details which can be observed while examining the history of a burnt fuse:
Various details which can be observed while examining the history of a burnt fuse:


Line 15: Line 16:
* A fuse may arise from a moving phase change in a wick without destroying the integrity of the wick, as for the phoenix-tub eater or the lightspeed wire. Indeed, all equilibria might be so regarded.
* A fuse may arise from a moving phase change in a wick without destroying the integrity of the wick, as for the phoenix-tub eater or the lightspeed wire. Indeed, all equilibria might be so regarded.


{|class="wikitable"  
=== Raw diagonal ===
!fuse !! periodicity !! initial namesake !! eventual equilibrium !! discovery info
 
|-
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|raw diagonal || trans = 0 <br> cycle = 1 <br> period = 1 || [[Image:RAWDGL.PNG|thumb]] || keeps on losing southwest end cell until all cells are lost || none
|{{EmbedViewer
|-
|rle          = x = 14, y = 13, rule = B3/S23
|hivemaker || trans = 14 <br> cycle = 4 <br> period = 4 || [[Image:hivemaker.png|thumb]] || [[Image:MKRHIV.PNG|thumb]] || none
12b2o$11bobo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$2bo$bo$o!
|-
|position    = center
|baker || trans = 7 <br> cycle = 2 <br> period = 4 || [[Image:baker.png|thumb]] || [[Image:MKRBKR.PNG|thumb]] || Keith McClelland
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|-
|caption      = Raw diagonal:<ref name="jslife" /> transient time 0, cycle 1, [[period]] 1
|beacon maker || trans = 16 <br> cycle = 4 <br> period = 8 || [[Image:beaconmaker.png|thumb]] || [[Image:MKRBCN.PNG|thumb]] || Steve Tower<ref>{{CiteSummersPattern|name=jslife|accessdate=December 2, 2010}}</ref>, Lifeline Volume 1<ref>{{CiteLifeline|vol=1|pages=page 6}}</ref>
}}
|-
 
|boat maker || trans = 5 <br> cycle = 2 <br> period = 4 || [[Image:boatmaker.png|thumb]] ||[[Image:MKRBOA.PNG|thumb]] || Lifeline Volume 1<ref>{{CiteLifeline|vol=1|pages=page 6}}</ref>
|[[Image:RAWDGL.PNG|200px]]{{br}}equilibrium: keeps on losing the SW end cell, evolves into a NW [[block]]
|-
|}
|harvester || trans = 5 <br> cycle = 4 <br> period = 4 || [[Image:harvester.png|thumb]] ||[[Image:MKRVST.PNG|thumb]] || David Poyner, February 1971 <i>Scientific American</i> column<ref>{{CiteLifeline|vol=1|pages=page 6}}</ref>
 
|-
=== Hivemaker ===
|Dual fuse || trans = 7 <br> cycle = 2 <br> period = 4 || [[Image:DUALIN.PNG|thumb]] ||[[Image:DUALEQ.PNG|thumb]] || none
 
|-
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|[[Tub]]s eating [[Phoenix]] ||  trans = 0 <br> cycle = 2 <br> period = 2 || [[Image:PHXTUB.PNG|thumb]] || loses a domino, lengthens barge, all at uniform width || none
|{{EmbedViewer
|-
|pname        = hivemaker
|Cow || 8 || || [[Image:cow.png|thumb]] || [[Don Woods]], Lifeline Volume 3<ref>{{CiteLifeline|vol=3|pages=page 20}}</ref>
|position    = center
|-
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|[[lightspeed wire]] || trans = 0 <br> cycle = 4 <br> period = 4  || [[Image:CWIRE.GIF|thumb]] || the glitch moves off to the right along a protected rail || none
|caption      = [[Hive]]maker: transient time 14, cycle 4, period 4
}}
 
|[[Image:MKRHIV.PNG]]{{br}}equilibrium
|}
 
=== Baker ===
 
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname        = baker
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|caption      = Baker:<ref name="jslife">{{CiteSummersPattern|name=jslife|accessdate=December 2, 2010}}</ref> Transient time 7, cycle 2, period 4{{br}}Discoverer: [[Keith McClelland]]
}}
 
|[[Image:MKRBKR.PNG]]{{br}}equilibrium
|}
 
=== Beacon maker ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname        = beaconmaker
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|caption      =  [[Beacon]] maker:<ref name="jslife" /> transient time 16, cycle 4, period 8{{br}}discoverer: [[Steve Tower]], Lifeline Volume 1<ref name="vol1p6">{{CiteLifeline|vol=1|pages=page 6}}</ref>
|style        = width:350px;
}}
 
|[[Image:MKRBCN.PNG]]{{br}}equilibrium
|}
 
=== Boat maker ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname        = boatmaker
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|caption      =  [[boat]] maker:<ref name="jslife" /> transient time 5, cycle 2, period 4{{br}}discovery: Lifeline Volume 1<ref name="vol1p6" />
}}
 
|[[Image:MKRBOA.PNG]]{{br}}equilibrium
|}
 
=== Harvester ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname        = harvester
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 14 ]]
|caption      = harvester:<ref name="jslife" /> transient time 5, cycle 4, period 4 {{br}}discovery: David Poyner, February 1971 <i>Scientific American</i> column<ref name="vol1p6" />
}}
 
|[[Image:MKRVST.PNG]]{{br}}equilibrium
|}
 
=== Ship maker ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname=shipmaker
|position=center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 8 HEIGHT 500 ]]
|caption      = [[ship]] maker:<ref name="post51" /> period 4{{br}}discovery: [[Nathaniel Johnston]]
|style        = width:300px;
}}
|}
 
=== Dual fuse ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname = dualfuse
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ]]
|caption      = Dual fuse: transient time 7, cycle 2, period 4
}}
 
[[Image:DUALEQ.PNG]]{{br}}            equilibrium
|}
 
=== Tubs eating phoenix ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname = tubseatingphoenix
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ]]
|caption      = [[tub]]s eating [[phoenix]]: transient time 0, cycle 2, period 2
}}
 
[[Image:PHXTUB.PNG]]{{br}}Equilibrium: loses a [[domino]], lengthens [[barge]], all at uniform width
|}
 
 
=== Cow ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450px;"
|{{EmbedViewer
|pname        = cow
|position    = center
|viewerconfig = #C [[ THUMBSIZE 2 ZOOM 10 ]]
|caption      = Cow:<ref name="vol3p20">{{CiteLifeline|vol=3|pages=page 20}}</ref> period 8{{br}}equilibrium: burns left-to-right, evolves into a [[block]] {{br}}Discoverer: [[Don Woods]]
}}
|}
 
=== Lightspeed wire ===
{{main|Lightspeed wire}}
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450;"
|[[Image:CWIRE.GIF]]{{br}}lightspeed wire: transient time 0, cycle 4, period 4{{br}}equilibrium: the glitch moves off to the right along a protected rail
|}
 
=== Beehive fuse ===
{|style="margin-left:auto; margin-right:auto; clear:both; text-align:center; width:450;"
|{{EmbedViewer
|pname        = beehivefuse
|position    = center
|viewerconfig = #C [[ THUMBSIZE 3 ZOOM 12 HEIGHT 560 ]]
|caption      = [[beehive]] fuse:<ref name="jslife"></ref> period 128{{br}}equilibrium: burns at 3c/32 until the [[house]] runs out of [[beehive]]s
|style        = width:400px;
|}}
|}
|}


==Reverse fuse==
==Reverse fuse==
{|
{|class="wikitable" style="margin-left:auto; margin-right:auto; clear:both; text-align:center"
|[[File:RVFUSE1.GIF|thumb|initial configuration of a reverse fuse]]
|[[File:RVFUSE1.GIF|thumb|initial configuration of a reverse fuse]]
|[[File:RVFUSE2.GIF|thumb|equilibrium configuration of a reverse fuse]]
|[[File:RVFUSE2.GIF|thumb|equilibrium configuration of a reverse fuse]]
|}
|}
As suggested by Bill Woods on Lifeline<ref>{{CiteLifeline|vol=3|pages=page 20}}</ref>, a '''reverse fuse''' is not so much the name of a fuse as a description of fuse behavior. Given that a wick is a stable one dimensional Life pattern and that a fuse and its burning refer to a progressive disruption of the wick, the expectation is that a growing cloud of debris will form as the wick progressively disintegrates. So, the ''reverse'' of this scenario would be that the combustion settles down into an orderly process.  
As suggested by Bill Woods on Lifeline,<ref name="vol3p20" /> a '''reverse fuse''' is not so much the name of a fuse as a description of fuse behavior. Given that a wick is a stable one dimensional Life pattern and that a fuse and its burning refer to a progressive disruption of the wick, the expectation is that a growing cloud of debris will form as the wick progressively disintegrates. So, the ''reverse'' of this scenario would be that the combustion settles down into an orderly process.  


Although the term refers to no particular fuse, a simple example will serve to illustrate the principle. Whereas a diagonal string of live cells constitutes a stable wick, a semiinfinite string ''burns'' by dropping the cell at the tip of its tail every generation. But a cluster of live cells surrounding the tail complicates the evolution; the simple variant of placing a domino at the tip is shown in the first figure.
Although the term refers to no particular fuse, a simple example will serve to illustrate the principle. Whereas a diagonal string of live cells constitutes a stable wick, a semiinfinite string ''burns'' by dropping the cell at the tip of its tail every generation. But a cluster of live cells surrounding the tail complicates the evolution; the simple variant of placing a domino at the tip is shown in the first figure.
Line 50: Line 167:
That fuse will burn for a while, leaving a residue behind. But eventually it will evolve into the form shown in the second figure; a pattern which reproduces itself in displaced form every fourth generation.  
That fuse will burn for a while, leaving a residue behind. But eventually it will evolve into the form shown in the second figure; a pattern which reproduces itself in displaced form every fourth generation.  


The raw diagonal fuse is a prolific source of variants, many of them reverse fuses.  
The raw diagonal fuse is a prolific source of variants, many of them reverse fuses.


==See also==
==See also==
*[[Superstring]]  
*[[Superstring]]  
*[[Wickeater]] <!-- This page needs to be created. -->
*[[C diagonal]]
*[[Blinker fuse]]
*[[Block fuse]]
*[[Bi-block fuse]]


==References==
==References==
<references />
<references>
<ref name="post51">
{{LinkForumThread
|p      = 51
|format = ref
|title  = Ship maker
|author = Elithrion
|date  = February 15, 2009
}}
</ref>
</references>


==External links==
==External links==
{{LinkLexicon|lex_f.htm|Fuse}}
* {{LinkLexicon|filename=lex_f.htm#fuse|patternname=Fuse}}
{{LinkLexicon|filename=lex_r.htm#reversefuse|patternname=Reverse fuse}}
* {{LinkLexicon|filename=lex_r.htm#reversefuse|patternname=Reverse fuse}}
* {{LinkForumThread|f=2|t=515|title=Fuse thread}}

Latest revision as of 16:28, 18 June 2025

A fuse is a wick that burns at one end, possibly creating byproducts. A clean fuse is much to be desired, even one leaving no residue. The messier the debris, the harder it would be to combine it with something else. Like pure glider generators, fuses were of early academic interest in the 1970s and often reported in Lifeline issues, but nowadays fuses that are not reburnable have been found to be so numerous that new examples no longer receive much attention.

Fuse may also refer to a still life component consisting of a diagonal line of two or more live cells. This article is about the first definition, above.

Examples

Various details which can be observed while examining the history of a burnt fuse:

  • It is usually named for a noteworthy initial condition or avatar, which may or may not reappear as the fuse burns. If it reappears, the smallest, or most symmetrical, phase would probably have been chosen as the namesake and initiator.
  • During and after startup a fuse may leave no residue, leave an initial residue which could change form or altogether disappear after a time, or persist for a long time.
  • Three times are important statistics for the fuse:
    • the transient time, after which it has entered a cycle
    • the length of the internal cycle, after which the avatar repeats
    • the length of the external cycle, which is the time for debris left by the burning to repeat, which may be a multiple of the internal cycle since it may require time to settle down. As the externally visible cycle, it is the one cited as the period of the fuse.
  • A fuse may arise from a moving phase change in a wick without destroying the integrity of the wick, as for the phoenix-tub eater or the lightspeed wire. Indeed, all equilibria might be so regarded.

Raw diagonal

x = 14, y = 13, rule = B3/S23 12b2o$11bobo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$2bo$bo$o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
Raw diagonal:[1] transient time 0, cycle 1, period 1
(click above to open LifeViewer)
equilibrium: keeps on losing the SW end cell, evolves into a NW block

Hivemaker

x = 17, y = 14, rule = B3/S23 15b2o$14bobo$13bo$12bo$11bo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$3o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
Hivemaker: transient time 14, cycle 4, period 4
(click above to open LifeViewer)
RLE: here Plaintext: here
equilibrium

Baker

x = 16, y = 14, rule = B3/S23 14b2o$13bobo$12bo$11bo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$3o$bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
Baker:[1] Transient time 7, cycle 2, period 4
Discoverer: Keith McClelland
(click above to open LifeViewer)
RLE: here Plaintext: here
equilibrium

Beacon maker

x = 16, y = 15, rule = B3/S23 14b2o$13bobo$12bo$11bo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$3o$2bo$2bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
Beacon maker:[1] transient time 16, cycle 4, period 8
discoverer: Steve Tower, Lifeline Volume 1[2]
(click above to open LifeViewer)
RLE: here Plaintext: here
equilibrium

Boat maker

x = 18, y = 17, rule = B3/S23 16b2o$15bobo$14bo3b$13bo4b$12bo5b$11bo6b$10bo7b$9bo8b$8bo9b$7bo10b$6bo 11b$5bo12b$5o13b$4bo13b$4bo13b$4bo13b$4bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
boat maker:[1] transient time 5, cycle 2, period 4
discovery: Lifeline Volume 1[2]
(click above to open LifeViewer)
RLE: here Plaintext: here
equilibrium

Harvester

x = 18, y = 15, rule = B3/S23 16b2o$15bobo$14bo$13bo$12bo$11bo$10bo$9bo$8bo$7bo$6bo$5bo$5o$4o$ob2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 14 ]]
harvester:[1] transient time 5, cycle 4, period 4
discovery: David Poyner, February 1971 Scientific American column[2]
(click above to open LifeViewer)
RLE: here Plaintext: here
equilibrium

Ship maker

x = 44, y = 43, rule = B3/S23 42b2o$41bobo$40bo$39bo$38bo$37bo$36bo$35bo$34bo$33bo$32bo$31bo$30bo$29b o$28bo$27bo$26bo$25bo$24bo$23bo$22bo$21bo$20bo$19bo$18bo$17bo$11b6o$10b o5bo$9bo6bo$10bo5bo$5b2o4bo4bo$4bo3bo3bo3bo$4bo2b3o3bobo$2bob2o2bobo3b o$bo7b3o$4b3o3bo$o6bo4bo$o2b2o2bobo2bo$bobobobob3o$2o2b2o$2o7bo$2b3o3b o$2b2ob2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 8 HEIGHT 500 ]]
ship maker:[3] period 4
discovery: Nathaniel Johnston
(click above to open LifeViewer)
RLE: here Plaintext: here

Dual fuse

x = 29, y = 28, rule = B3/S23 2$21b2o$22bo$21bo$20bo3b2o$19bo3bobo$18bo3bo$17bo3bo$16bo3bo$15bo3bo$ 14bo3bo$13bo3bo$12bo3bo$11bo3bo$10bo3bo$9bo3bo$8bo3bo$7bo3bo$6bo3bo$5b o3bo$4bo3bo$3bo3bo$2bo3bo$bo3bo$2bobo$3bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ]]
Dual fuse: transient time 7, cycle 2, period 4
(click above to open LifeViewer)
RLE: here Plaintext: here


equilibrium

Tubs eating phoenix

x = 23, y = 23, rule = B3/S23 21b2o2$19b2o2$17b2o2$15b2o2$13b2o2$11b2o2$9b2o2$7b2o2$5b2o2$3b2o$2bo$ bobo$obo$2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ]]
tubs eating phoenix: transient time 0, cycle 2, period 2
(click above to open LifeViewer)
RLE: here Plaintext: here


Equilibrium: loses a domino, lengthens barge, all at uniform width


Cow

x = 40, y = 7, rule = B3/S23 2o7b2o2b2o2b2o2b2o2b2o2b2o2b2o$2o4bob3o2b2o2b2o2b2o2b2o2b2o2b2o3b2o$4b 2obo29bobo$4b2o3b29o$4b2obo30bo$2o4bob3o2b2o2b2o2b2o2b2o2b2o2b2o2b2o$ 2o7b2o2b2o2b2o2b2o2b2o2b2o2b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 2 ZOOM 10 ]]
Cow:[4] period 8
equilibrium: burns left-to-right, evolves into a block
Discoverer: Don Woods
(click above to open LifeViewer)
RLE: here Plaintext: here

Lightspeed wire

Main article: Lightspeed wire

lightspeed wire: transient time 0, cycle 4, period 4
equilibrium: the glitch moves off to the right along a protected rail

Beehive fuse

x = 30, y = 32, rule = B3/S23 2ob2o$o3bo$b3o3$3b2o$2bo2bo$3b2o6$7bo$6bobo$6bobo$7bo$15b2o$14bo2bo$ 15b2o6$19bo$18bobo$18bobo$19bo$27b2o$26bo2bo$27b2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ THUMBSIZE 3 ZOOM 12 HEIGHT 560 ]]
beehive fuse:[1] period 128
equilibrium: burns at 3c/32 until the house runs out of beehives
(click above to open LifeViewer)
RLE: here Plaintext: here

Reverse fuse

initial configuration of a reverse fuse
equilibrium configuration of a reverse fuse

As suggested by Bill Woods on Lifeline,[4] a reverse fuse is not so much the name of a fuse as a description of fuse behavior. Given that a wick is a stable one dimensional Life pattern and that a fuse and its burning refer to a progressive disruption of the wick, the expectation is that a growing cloud of debris will form as the wick progressively disintegrates. So, the reverse of this scenario would be that the combustion settles down into an orderly process.

Although the term refers to no particular fuse, a simple example will serve to illustrate the principle. Whereas a diagonal string of live cells constitutes a stable wick, a semiinfinite string burns by dropping the cell at the tip of its tail every generation. But a cluster of live cells surrounding the tail complicates the evolution; the simple variant of placing a domino at the tip is shown in the first figure.

That fuse will burn for a while, leaving a residue behind. But eventually it will evolve into the form shown in the second figure; a pattern which reproduces itself in displaced form every fourth generation.

The raw diagonal fuse is a prolific source of variants, many of them reverse fuses.

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Jason Summers' jslife pattern collection. Retrieved on December 2, 2010.
  2. ↑ 2.0 2.1 2.2 Robert Wainwright (March 1971). Lifeline, vol 1, page 6.
  3. ↑ Elithrion (February 15, 2009). Ship maker (discussion thread) at the ConwayLife.com forums
  4. ↑ 4.0 4.1 Robert Wainwright (September 1971). Lifeline, vol 3, page 20.
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