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:L112 A composite conduit, one of the original sixteen Herschel conduits, discovered by Dave Buckingham in July 1996. It is made up of two elementary conduits, HLx53B + BFx59H. After 112 ticks, it produces a Herschel turned 90 degrees counterclockwise at (12, -33) relative to the input. Its recovery time is 61 ticks; this can be reduced slightly by removing the output glider, either with a specialized eater (as in the original true p59 gun), or with a sparker as in most of the Quetzal guns. It can be made Spartan by replacing the aircraft carrier with an eater1. A ghost Herschel in the pattern below marks the output location:

	...............OO.......
	...............O........
	.............OOO........
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	........................
	.............OO.........
	.............OO.........
	....OO..................
	....O..O................
	OO....OO................
	.O....................OO
	.O.O..................O.
	..OO................O.O.
	....................OO..
	........................
	........................
	........................
	........................
	........................
	..O.....................
	..O.O...................
	..OOO...................
	....O...................
	........................
	..............OO........
	..............OO..OO....
	..................O.O...
	....................O...
	....................OO..

:L156 A composite conduit, one of the original sixteen Herschel conduits, discovered by Dave Buckingham in August 1996. It is made up of three elementary conduits, HLx69R + RF28B + BFx59H. After 156 ticks, it produces a Herschel turned 90 degrees counterclockwise at (17, -41) relative to the input. Its recovery time is 62 ticks. It can be made Spartan by replacing the snake with an eater1 in one of two orientations. A ghost Herschel in the pattern below marks the output location:

	...................OO........
	...................O.........
	.................OOO.........
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.................OO..........
	.................OO..........
	.............................
	........OO.O.................
	........O.OO.................
	..........................OO.
	..........................O..
	........................O.O..
	........................OO...
	.............................
	.........O...................
	.........OOO.................
	O...........O................
	OOO........OO..............O.
	...O......................O.O
	..OO.......................O.
	.............................
	.............................
	.............................
	.............................
	.............................
	.............................
	.O....................OO.....
	.O.O..................O.O....
	.OOO....................O....
	...O...........OO.......OO...
	...............O.............
	................OOO..........
	..................O..........

:lake Any still life consisting of a simple closed curve made from diagonally connected dominoes. The smallest example is the pond, and the next smallest is this (to which the term is sometimes restricted):

	....OO....
	...O..O...
	...O..O...
	.OO....OO.
	O........O
	O........O
	.OO....OO.
	...O..O...
	...O..O...
	....OO....

:lane A path traveled by a glider, or less commonly a spaceship such as a loafer. The lane is centered on the line of symmetry (if any) of the spaceship in question. If a lane is clear, then the spaceship can travel along it without colliding or interfering with any other objects.

Diagonal lanes are often numbered consecutively, in half-diagonals (hd). Occasionally diagonal lane measurements are given in quarter-diagonals (qd), in part because diagonally symmetric spaceships have a line of symmetry 1qd away from the lines available for gliders. It's also convenient that moving a glider forward by 100qd (for example) has the same effect as evolving the same glider for 100 ticks.

:Laputa (p2) Found by Rich Schroeppel, September 1992.

	...OO.OO....
	...OO.O...OO
	........O..O
	.OOOOOO.OOO.
	O..O.O......
	OO...O.OO...
	....OO.OO...

:large prime oscillator Any oscillator with a relatively small bounding box whose period is a very large prime. (If the bounding-box restriction is removed, then eight gliders travelling in a four-Snark loop would provide a trivial example for any chosen prime.) The first such oscillator was built by Gabriel Nivasch in 2003. The current record holder is an oscillator constructed by Adam P. Goucher with a period that is a Mersenne prime with 13,395 digits (244497-1).

The next higher Mersenne-prime oscillator, period 286243-1, could be constructed with semi-Snarks and would actually be smaller than the current record holder, but as of November 2017 the construction of this pattern has not yet been completed.

:large S = big S

:Lidka (stabilizes at time 29053) A methuselah found by Andrzej Okrasinski in July 2005.

	..........OOO..
	..........O....
	..........O...O
	...........O..O
	............OOO
	...............
	.O.............
	O.O............
	.O.............
The following variant, pointed out by David Bell, has two fewer cells and lasts two generations longer.
	..........OOO..
	...............
	...........OO.O
	............O.O
	..............O
	...............
	.O.............
	O.O............
	.O.............

:Life A 2-dimensional 2-state cellular automaton discovered by John Conway in 1970. The states are referred to as ON and OFF (or live and dead). The transition rule is as follows: a cell that is ON will remain ON in the next generation if and only if exactly 2 or 3 of the 8 adjacent cells are also ON, and a cell that is OFF will turn ON if and only if exactly 3 of the 8 adjacent cells are ON. (This is more succinctly stated as: "If 2 of your 8 nearest neighbours are ON, don't change. If 3 are ON, turn ON. Otherwise, turn OFF.")

:Life32 A freeware Life program by Johan Bontes for Microsoft Windows 95/98/ME/NT/2000/XP: https://github.com/JBontes/Life32/.

:LifeHistory A multistate CA rule supported by Golly, equivalent to two-state B3/S23 Life but with several additional states intended for annotation purposes. A "history" state records whether an off cell has ever turned on in the past, and other states allow on and off cells to be permanently or temporarily marked, without affecting the evolution of the pattern.

:LifeLab A shareware Life program by Andrew Trevorrow for the Macintosh (MacOS 8.6 or later): http://www.trevorrow.com/lifelab/.

:LifeLine A newsletter edited by Robert Wainwright from 1971 to 1973. During this period it was the main forum for discussions about Life. The newsletter was nominally quarterly, but the actual dates of its eleven issues were as follows:

	Mar, Jun, Sep, Dec 1971
	Sep, Oct, Nov, Dec 1972
	Mar, Jun, Sep 1973

:Lifenthusiast A Life enthusiast. Term coined by Robert Wainwright.

:lifesrc David Bell's Life search program for finding new spaceships and oscillators. This is a C implementation of an algorithm developed by Dean Hickerson in 6502 assembler.

Although lifesrc itself is a command-line program, Jason Summers has made a GUI version called WinLifeSearch for Microsoft Windows. A Java version, JavaLifeSearch, was written in November 2012 by Karel Suhajda.

The lifesrc algorithm is only useful for very small periods, as the amount of computing power required rises rapidly with increasing period. For most purposes, period 7 is the practical limit with current hardware.

Lifesrc is available from http://tip.net.au/~dbell/ (source code only). Compare gfind.

:LifeViewer A scriptable Javascript Life pattern viewer written by Chris Rowett, used primarily on the conwaylife.com discussion forums.

:light bulb (p2) Found in 1971.

	.OO.O..
	.O.OO..
	.......
	..OOO..
	.O...O.
	.O...O.
	..O.O..
	O.O.O.O
	OO...OO
The same rotor can be embedded in a slightly smaller stator like this:
	...O.....
	.OOO.....
	O........
	OOOOOO...
	......O..
	..O...O..
	..OO.O...
	......OOO
	........O

:lightspeed bubble A type of negative spaceship traveling through the zebra stripes agar. The center of the bubble is simple empty space, and the length and/or width of the bubble can usually be extended to any desired size.

Below is a small stabilized section of agar containing a sample lightspeed bubble, found by Gabriel Nivasch in August 1999. The bubble travels to the left at the speed of light, so it will eventually reach the edge of any finite patch and destroy itself and its supporting agar.

	.O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O...
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.............................................................O
	.OOOOOOOOOOOOO..OOO..OOO..OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O..............OO...OO...OO........O..........................
	.OOOOOOOOOOOOO...OO...OO...O.OO.O....OOOOOOOOOOOOOOOOOOOOOOOO.
	.............................OO.....O........................O
	.OOOOOOOOOOOOO.................OOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O...............................O.............................
	.OOOOOOOOOOOOO...................OOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.................................O....O......................O
	.OOOOOOOOOOOOO...................OO....OOOOOOOOOOOOOOOOOOOOOO.
	O................................O.....O....O.................
	.OOOOOOOOOOOOO...................OO....OO....OOOOOOOOOOOOOOOO.
	.................................O.....O.....O....O..........O
	.OOOOOOOOOOOOO...................OO....OO....OO....OOOOOOOOOO.
	O................................O.....O.....O.....O....O.....
	.OOOOOOOOOOOOO...................OO....OO....OO....OO....OOOO.
	.................................O.....O.....O.....O.....O...O
	.OOOOOOOOOOOOO...................OO....OO....OO....OO....OOOO.
	O................................O.....O.....O.....O....O.....
	.OOOOOOOOOOOOO...................OO....OO....OO....OOOOOOOOOO.
	.................................O.....O.....O....O..........O
	.OOOOOOOOOOOOO...................OO....OO....OOOOOOOOOOOOOOOO.
	O................................O.....O....O.................
	.OOOOOOOOOOOOO...................OO....OOOOOOOOOOOOOOOOOOOOOO.
	.................................O....O......................O
	.OOOOOOOOOOOOO...................OOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O...............................O.............................
	.OOOOOOOOOOOOO.................OOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.............................OO.....O........................O
	.OOOOOOOOOOOOO...OO...OO...O.OO.O....OOOOOOOOOOOOOOOOOOOOOOOO.
	O..............OO...OO...OO........O..........................
	.OOOOOOOOOOOOO..OOO..OOO..OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.............................................................O
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O...

An open problem related to lightspeed bubbles was whether large extensible empty areas could be created whose length was not proportional to the width (as it must be in the above case, due to the tapering back edge). This was solved in February 2017 by Arie Paap; a simple period-2 solution is shown below.

	...O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O...
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O...........................................................O
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	.............................................................
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O.....................................................O.....O
	.OOOOOOOOOOOOOOOOOOOO..OOO..OOO..OOO..OOOOOOOO..OOOO...OOOOO.
	......................OO...OO...OO...OO........OO.....O......
	.OOOOOOOOOOOOOOOOOOOO...OO...OO...OO...OOOOOOO...O.OO..OOOOO.
	O.........................................O........OO.......O
	.OOOOOOOOOOOOOOOOOOOO......................OO.O......OOOOOOO.
	...........................................O............O....
	.OOOOOOOOOOOOOOOOOOOO......................O.............OOO.
	O..........................................OO.....OO....O...O
	.OOOOOOOOOOOOOOOOOOOO......................OO...OO...O.OOOOO.
	...........................................O..O.OO...O.......
	.OOOOOOOOOOOOOOOOOOOO......................O......OO...OOOOO.
	O..........................................OO..........O....O
	.OOOOOOOOOOOOOOOOOOOO......................OO..........OOOOO.
	...........................................O......OO.O.......
	.OOOOOOOOOOOOOOOOOOOO......................O..O.OO...O.OOOOO.
	O..........................................OO...OO......O...O
	.OOOOOOOOOOOOOOOOOOOO......................OO.....OO.....OOO.
	...........................................O............O....
	.OOOOOOOOOOOOOOOOOOOO......................O...........OOOOO.
	O..........................................OO.....OO.OO.....O
	.OOOOOOOOOOOOOOOOOOOO......................OO...OO...OO..OOO.
	...........................................O..O.OO.....OO....
	.OOOOOOOOOOOOOOOOOOOO......................O......OO....OOOO.
	O..........................................OO...............O
	.OOOOOOOOOOOOOOOOOOOO......................OO...........OOOO.
	...........................................O......OO...OO....
	.OOOOOOOOOOOOOOOOOOOO......................O..O.OO...OO..OOO.
	O..........................................OO...OO...OO.....O
	.OOOOOOOOOOOOOOOOOOOO......................OO.....OO...OOOOO.
	...........................................O............O....
	.OOOOOOOOOOOOOOOOOOOOOO.....O.....O.....O..O.O...........OOO.
	O.........................OO....OO....OO...O...O.O.......O..O
	.OOOOOOOOOOOOOOOOOOOOOOOO.OO.OO.OO.OO.OO.OOOOOOOOO.......OOO.
	........................................................O....
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO...OOOOOOO.
	O..................................................OO.......O
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO..OOOOOOOO.
	.............................................................
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	O...........................................................O
	.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.
	...O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O..O...

:lightspeed ribbon = superstring

:lightspeed telegraph = telegraph.

:lightspeed wire Any wick that can burn non-destructively at the speed of light. Lightspeed wires are a type of reburnable fuse. These are potentially useful for various things, but so far the necessary mechanisms are very large and unwieldy. In October 2002, Jason Summers discovered a lightspeed reaction traveling through an orthogonal chain of beehives. Summers completed a period-1440 lightspeed telegraph based on this reaction in 2003.

	...O...........................................................
	.O...O.........................................................
	.O....O....OO.OO...............................................
	O......O...OOOOOO...OO...OO...OO...OO...OO...OO...OO...OO...OO.
	O......O..O......O.O..O.O..O.O..O.O..O.O..O.O..O.O..O.O..O.O..O
	OO.....O...OOOOOO...OO...OO...OO...OO...OO...OO...OO...OO...OO.
	......O....OO.OO...............................................
	....O..........................................................

A stable lightspeed transceiver mechanism using this same signal reaction, the p1 telegraph, was constructed by Adam P. Goucher in 2010; the bounding boxes of both the transmitter and receiver are over 5000 cells on a side. A more compact periodic high-bandwidth telegraph with a much improved transmission rate was completed by Louis-François Handfield in 2017.

The following diagram shows an older example of a lightspeed wire, with a small defect that travels along it at the speed of light. As of this writing (November 2017) no method has been found of creating such a defect in the upstream end of this particular stable wire, or of non-destructively detecting the arrival of the defect and repairing the wire at the downstream end.

	....OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO....
	....OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO....
	..........................................................
	..OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO..
	.O......O...............................................O.
	O.OOOOO....OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.O
	.O.....O................................................O.
	..OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO..
	..........................................................
	....OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO....
	....OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO..OO....

:lightweight emulator = LW emulator

:lightweight spaceship = LWSS

:lightweight volcano = toaster

:linear growth A growth rate proportional to T, where T is the number of ticks that a pattern has been run. Compare superlinear growth, quadratic growth.

:linear propagator A self-replicating pattern in which each copy of a pattern produces one child that is an exact copy of itself. The child pattern then blocks the parent from any further replication. An example was constructed by Dave Greene on 23 November 2013, with a construction arm using two glider lanes separated by 9hd. By some definitions, due to its limited one-dimensional growth pattern, the linear propagator is not a true replicator. Compare quadratic replicator.

:line crosser A pattern which is able to send a signal across an infinite diagonal line of live cells without destroying the line. David Bell built one in August 2006. It uses many one-shot period 44160 glider guns on both sides of the line having the proper synchronization to create the reactions shown in line-cutting reaction and line-mending reaction.

An input glider can arrive at any multiple of 44160 generations to first cut the line, then send a glider through the gap, and finally mend the line while leaving an output glider on the other side.

A line crosser whose complete mechanism is on one side of the line is theoretically possible, using single-channel construction methods for example.

:line-cutting reaction A reaction that can cut an infinite diagonal line of cells, leaving a gap with both ends sealed. Such a reaction is demonstrated below. In actual use the reaction should be spread out so that the incoming LWSSes don't conflict. See line-mending reaction for a way to mend the gap.

	.........................OO.................................
	............OO...........O..................................
	..........OO.OO...........O.................................
	..........OOOO.............O................................
	...........OO...............O...............................
	................OO...........O..............................
	...............O.O............O.............................
	.................O.............O............................
	................................O...........................
	.................................O..........................
	..................................O.........................
	...................................O........................
	.......................O............O.......................
	......................OOO............O......................
	......................O.OO............O.....................
	O..O...................OOO.............O....................
	....O..................OO...............O...................
	O...O....................................O..................
	.OOOO.....................................O.................
	...........................................O................
	............................................O...............
	.............................................O..............
	...................................OO.........O.............
	....................................OO.........O............
	...................................O............O...........
	.................................................O..........
	..................................................O.........
	.....................................OOO...........O........
	....................................O..O............O.......
	.......................................O.............O......
	.......................................O..............O.....
	....................................O.O................O....
	........................................................O...
	.........................................................O.O
	.......OOO................................................OO
	.........O............OO......OOO..........OOOO.............
	........O............O.O........O.........O...O.............
	.......................O.......O..............O.............
	..........................................O..O..............
	............................................................
	............................................................
	............................................................
	....................................................OO......
	.....................................................OO.....
	....................................................O.......
	............................................................
	........................................................OOO.
	........................................................O..O
	........................................................O...
	........................................................O...
	.........................................................O.O
	.......................OO...................................
	......................O.O...................................
	........................O...................................
	............................................................
	..........................................O.................
	.........................................OOO................
	.........................................O.OO...............
	..........................................OOO...............
	..........................................OO................

:line-mending reaction A reaction which can fully mend a sealed gap in an infinite diagonal line of cells, such as the one produced by a line-cutting reaction. Such a reaction is demonstrated below. See the line cutting reaction for a way of creating the gliders traveling parallel to the line.

	...........OO.............................................
	...........O..............................................
	............O.............................................
	...O.O.......O............................................
	....OO........O...........................................
	....O..........O..........................................
	................O...................................O.....
	.................O................................OO......
	..................O................................OO.....
	...................O......................................
	....................O.....................................
	.....................O.....................O.O............
	......................O....................OO.............
	.......................O....................O.............
	........................O.................................
	.........................O................................
	..........................O...............O...............
	...........................O.............O................
	............................O............OOO..............
	.............................O............................
	............................OO............................
	..........................................................
	..........................................................
	..........................................................
	...........................................O.O............
	...........................................OO.......O..O..
	............................................O......O......
	...................................OOO.............O...O..
	.....................................O.............OOOO...
	....................................O.....................
	.......................................OO.................
	.......................................O.O................
	..........................................O...............
	...........................................O..............
	...............................OO...........O.............
	..............................O.O............O............
	................................O.............O.......OO..
	.............O..........................OO.....O.....OO...
	.............OO.........................O.O.....O......O..
	............O.O.....OO..................O........O........
	...................O.O............................O.......
	.O...................O.............................O......
	.OO.....O...........................................O.....
	O.O.....OO...........................................O....
	.......O.O............................................O...
	.......................................................O.O
	........................................................OO
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	..........................................................
	.................................O........................
	................................OOO.......................
	...............................OO.O.......................
	...............................OOO........................
	................................OO........................

This reaction uses spaceships on both sides of the line which need to be synchronized to each other, for example by passing a glider through the gap to trigger the creation of the required spaceships and gliders.

No simple mechanism is known to mend the gap which lies completely on one side of the line. However, it is technically possible to use construction arm technology to push objects through the gap to build and trigger a seed for the required synchronized signals on the other side.

:line puffer A puffer which produces its output by means of an orthogonal line of cells at right angles to the direction of travel. The archetypal line puffer was found by Alan Hensel in March 1994, based on a spaceship found earlier that month by Hartmut Holzwart. The following month Holzwart found a way to make extensible c/2 line puffers, and Hensel found a much smaller stabilization the following day. But in October 1995 Tim Coe discovered that for large widths these were often unstable, although typically lasting millions of generations. In May 1996, however, Coe found a way to fix the instability. The resulting puffers appear to be completely stable and to exhibit an exponential increase in period as a function of width, although neither of these things has been proved.

Line puffers have enabled the construction of various difficult periods for c/2 spaceships and puffers, including occasionally periods which are not multiples of 4 and which would therefore be impossible to attain with the usual type of construction based on standard spaceships. (See frothing puffer for another method of constructing such periods.) In particular, the first c/2 rake with period not divisible by 4 was achieved in January 2000 when David Bell constructed a p42 backrake by means of line puffers.

See also hivenudger and puff suppressor.

:line ship A spaceship in which the front end is a linestretcher, the line being eaten by the back end.

:linestretcher A wickstretcher that stretches a single diagonal line of cells. The first example was constructed by Jason Summers in March 1999; this was c/12 and used switch engine based puffers found earlier by Dean Hickerson. The first c/4 example was found by Hartmut Holzwart in November 2004.

:loading dock (p3) Found by Dave Buckingham, September 1972.

	....O....
	..OOO....
	.O...OO..
	O.OO...O.
	.O...OO.O
	..OO...O.
	....OOO..
	....O....

:loaf (p1)

	.OO.
	O..O
	.O.O
	..O.

:loafer (c/7 orthogonally, p7) A small c/7 spaceship discovered by Josh Ball on 17 February 2013:

	.OO..O.OO
	O..O..OO.
	.O.O.....
	..O......
	........O
	......OOO
	.....O...
	......O..
	.......OO

It has a known 8-glider construction recipe, probably not minimal, discovered on the following day:

	.................................O
	...............................OO.
	................................OO
	.........O........................
	.O........O.......................
	..O.....OOO.......................
	OOO...............................
	..................................
	..................................
	.....O............................
	......O...........................
	....OOO...........................
	........................O.O.......
	.........................OO.......
	.........................O........
	..................................
	...........................O.O....
	...........................OO.....
	............................O.....
	...............................OOO
	...............................O..
	................................O.
	..................................
	..................................
	..................................
	..................................
	..................................
	..................................
	.....OO...........................
	......OO..........................
	.....O............................
The loafer was therefore the first new glider-constructible spaceship in almost a decade. (A glider synthesis for a 2c/5 ship, 60P5H2V0, was found in March 2003.)

:loaflipflop (p15) Here four pentadecathlons hassle a loaf. Found by Robert Wainwright in 1990.

	................O.................
	...............OOO................
	..................................
	..................................
	...............OOO................
	..................................
	...............O.O................
	...............O.O................
	..................................
	...............OOO................
	..................................
	..................................
	...............OOO................
	................O.................
	..................................
	.O..O.OO.O..O...............OO....
	OO..O....O..OO...OO.......O....O..
	.O..O.OO.O..O...O..O.....O......O.
	................O.O.....O........O
	.................O......O........O
	........................O........O
	.........................O......O.
	..........................O....O..
	............................OO....
	..................OOO.............
	.................O...O............
	................O.....O...........
	..................................
	...............O.......O..........
	...............O.......O..........
	..................................
	................O.....O...........
	.................O...O............
	..................OOO.............

:loaf on loaf = bi-loaf

:loaf pull The following glider/loaf collision, which pulls a loaf (3,1) toward the glider source:

	.O.....
	O.O....
	O..O...
	.OO....
	.......
	.......
	....OOO
	....O..
	.....O.

:loaf siamese barge (p1)

	..OO.
	.O..O
	O.O.O
	.O.O.
	..O..

:lobster (c/7 diagonally, p7) A spaceship discovered by Matthias Merzenich in August 2011, the first diagonally traveling c/7 spaceship to be found. It consists of two gliders pulling a tagalong that then rephases them.

	............OOO...........
	............O.............
	.............O..OO........
	................OO........
	............OO............
	.............OO...........
	............O..O..........
	..........................
	..............O..O........
	..............O...O.......
	...............OOO.O......
	....................O.....
	OO..O.O.............O.....
	O.O.OO.............O......
	O....O..OO.............OO.
	......O...O......OO..OO..O
	..OO......O......O..O.....
	..OO....O.O....OO.........
	.........O.....O...O...O..
	..........O..O....OO......
	...........OO...O.....O.O.
	...............O........OO
	...............O....O.....
	..............O...O.......
	..............O.....OO....
	...............O.....O....

:logarithmic growth A pattern whose population or bounding box grows no faster than logarithmically, asymptotic to n.log(t) for some constant n. The first such pattern constructed was the caber tosser whose population is logarithmic, but whose bounding box still grows linearly. The first pattern whose bounding box and population both grow logarithmically was constructed by Jason Summers with Gabriel Nivasch in 2003. For a pattern with a slower growth rate than this, see Osqrtlogt.

:LoM = lumps of muck

:lone dot agar An agar in which every live cell is isolated in every generation. There are many different lone dot agars. All of them are phoenixes. In 1995 Dean Hickerson and Alan W. Hensel found stabilizations for finite patches of ten lone dot agars to create period 2 oscillators. One of these is shown below:

	....OO..OO..OO..OO..OO..OO..OO..OO....
	....O..O.O..O..O.O..O..O.O..O..O.O....
	.....O.......O.......O.......O........
	........O.......O.......O.......O.....
	OO..O.O.....O.O.....O.O.....O.O.....OO
	O.O.....O.O.....O.O.....O.O.....O.O..O
	....O.......O.......O.......O.......O.
	.O.......O.......O.......O.......O....
	O..O.O.....O.O.....O.O.....O.O.....O.O
	OO.....O.O.....O.O.....O.O.....O.O..OO
	.....O.......O.......O.......O........
	........O.......O.......O.......O.....
	OO..O.O.....O.O.....O.O.....O.O.....OO
	O.O.....O.O.....O.O.....O.O.....O.O..O
	....O.......O.......O.......O.......O.
	.O.......O.......O.......O.......O....
	O..O.O.....O.O.....O.O.....O.O.....O.O
	OO.....O.O.....O.O.....O.O.....O.O..OO
	.....O.......O.......O.......O........
	........O.......O.......O.......O.....
	OO..O.O.....O.O.....O.O.....O.O.....OO
	O.O.....O.O.....O.O.....O.O.....O.O..O
	....O.......O.......O.......O.......O.
	.O.......O.......O.......O.......O....
	O..O.O.....O.O.....O.O.....O.O.....O.O
	OO.....O.O.....O.O.....O.O.....O.O..OO
	.....O.......O.......O.......O........
	........O.......O.......O.......O.....
	OO..O.O.....O.O.....O.O.....O.O.....OO
	O.O.....O.O.....O.O.....O.O.....O.O..O
	....O.......O.......O.......O.......O.
	.O.......O.......O.......O.......O....
	O..O.O.....O.O.....O.O.....O.O.....O.O
	OO.....O.O.....O.O.....O.O.....O.O..OO
	.....O.......O.......O.......O........
	........O.......O.......O.......O.....
	....O.O..O..O.O..O..O.O..O..O.O..O....
	....OO..OO..OO..OO..OO..OO..OO..OO....

:lonely bee = worker bee

:long A term applied to an object that is of the same basic form as some standard object, but longer. For examples see long barge, long boat, long bookend, long canoe, long shillelagh, long ship and long snake.

:long^3 The next degree of longness after long long. Some people prefer "extra long".

:long^4 The next degree of longness after long^3. Some people prefer "extra extra long".

:long barge (p1)

	.O...
	O.O..
	.O.O.
	..O.O
	...O.

:long boat (p1)

	.O..
	O.O.
	.O.O
	..OO
A long boat can be used as a 90-degree or 180-degree one-time turner.

:long bookend The following induction coil, longer than a bookend.

	...OO
	O...O
	OOOO.

:long canoe (p1)

	....OO
	.....O
	....O.
	...O..
	O.O...
	OO....

:long hat = loop

:long hook = long bookend

:long house = dock

:long integral (p1)

	..OO
	.O.O
	.O..
	..O.
	O.O.
	OO..

:long long The next degree of longness after long. Some people prefer "very long".

:long long barge (p1)

	.O....
	O.O...
	.O.O..
	..O.O.
	...O.O
	....O.

:long long boat (p1)

	.O...
	O.O..
	.O.O.
	..O.O
	...OO

:long long canoe (p1)

	.....OO
	......O
	.....O.
	....O..
	...O...
	O.O....
	OO.....

:long long ship (p1)

	OO...
	O.O..
	.O.O.
	..O.O
	...OO

:long long snake (p1)

	OO....
	O.O...
	...O.O
	....OO

:long shillelagh (p1)

	OO..OO
	O..O.O
	.OO...

:long ship (p1)

	OO..
	O.O.
	.O.O
	..OO

:long sinking ship = long canoe

:long snake (p1)

	OO...
	O.O.O
	...OO

:loop (p1)

	.OO..
	O..O.
	.O.O.
	OO.OO

:looping spaceship = reflectorless rotating oscillator

:lossless elbow A stationary elbow in a construction arm toolkit that allows a recipe to turn a corner with no exponential increase in construction cost. Compare slow elbow. It is theoretically possible to construct lossless elbows for early construction arms such as the one in the 10hd Demonoid, but these would currently have to be very large.

The lossless elbow that has been used the most in practice is the Snark, which can be constructed directly on a single-channel construction lane using a Snarkmaker recipe. Controlled demolition of a Snark is also possible, to remove a temporary elbow that is no longer needed, and leave a hand target in its place if necessary for further construction.

A Silver reflector was used as a lossless elbow in the first spiral growth pattern, attached to a separate universal constructor component.

:low-density Life = sparse Life

:lumps of muck The common evolutionary sequence that ends in the blockade. The name is sometimes used of the blockade itself, and can in general be used of any stage of the evolution of the stairstep hexomino.

:LW emulator (p4) The smallest (and least useful) emulator, found by Robert Wainwright in June 1980.

	..OO.O..O.OO..
	..O........O..
	...OO....OO...
	OOO..OOOO..OOO
	O..O......O..O
	.OO........OO.

:LWSS (c/2 orthogonally, p4) A lightweight spaceship, the smallest known orthogonally moving spaceship, and the second most common (after the glider). Found by Conway when one formed from a random soup in 1970. See also MWSS and HWSS.

	.O..O
	O....
	O...O
	OOOO

The LWSS possesses a tail spark which can easily perturb other objects which grow into its path. The spaceship can also perturb some objects in additional ways. For examples, see blinker ship, hivenudger, and puffer train.

Dave Buckingham found that the LWSS can be synthesized in several different ways using three gliders, and can be constructed from two gliders and another small object in several more ways. Here is the fastest synthesis:

	.O.....
	O......
	OOO....
	.....OO
	....OO.
	......O
	.......
	..OO...
	...OO..
	..O....

:LWSS emulator = LW emulator

:LWSS-glider bounce The following reaction in which a LWSS and a glider collide to form a glider heading back between the two input paths:

	.OOOO........
	O...O........
	....O.....OOO
	O..O......O..
	...........O.
This is one way to inject a glider into a existing glider stream. The infinite glider hotel uses this reaction.

:LWSS-LWSS bounce The following symmetric reaction in which two LWSSs collide head-on to form two gliders heading apart.

	...O.......O...
	....O.....O....
	O...O.....O...O
	.OOOO.....OOOO.
This provides one way to inject a glider into a existing glider stream. Another use is described in metamorphosis.

:LWSS-to-G See 135-degree MWSS-to-G.

:LWTDS Life Worker Time Deficiency Syndrome. Term coined by Dieter Leithner to describe the problem of having to divide scarce time between Life and real life.

:LW volcano = toaster

:Lx200 A composite conduit, one of the original sixteen Herschel conduits, discovered by Paul Callahan in June 1997. It is made up of two elementary conduits, HL141B + BFx59H. The Lx200 and F166 conduits are the two original dependent conduits (several more have since been discovered.) After 200 ticks, it produces an inverted Herschel turned 90 degrees counterclockwise at (17, -40) relative to the input. Its recovery time is 90 ticks. It can be made Spartan by replacing the snakes with eater1s in one of two orientations. A ghost Herschel in the pattern below marks the output location:

	.....................OO.............
	......................O.............
	......................OOO...........
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	.......................OO...........
	.......................OO...........
	....................................
	..............................O.OO..
	..............................OO.O..
	....................................
	....................................
	..............O.OO..................
	..............OO.O..................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	....................................
	................................OO..
	................................O.O.
	.OO...............................O.
	OOO.OO............................OO
	.OO.OOO.OO..........................
	OOO.OO..OO..........................
	OO..................................
	....................................
	....................................
	....................................
	................................OO..
	................................OO..
	....................................
	......OO............................
	.......O............................
	....OOO.........................OO..
	....O...........................OO..
	..................OO................
	.................O.O................
	.................O..................
	................OO........OO........
	..........................O.........
	...........................OOO......
	.............................O......
The input shown here is a Herschel great-grandparent, since the input reaction is catalysed by the transparent block before the Herschel's standard form can appear.
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