Game of Life News

Hartmut Holzwart has found a new type of Period 8 Block Puffer.

Posted by HKoenig at 07:51 | Permalink

Back in February, Jason Summers constructed a complex assembly of c/2 orthogonal rakes that builds a zigzag wick. The pattern uses glider constructions similar to those found in David Bell's c/12 diagonal wickstretchers from last year.

Posted by Dave Greene at 02:28 | Permalink

Here is a sample Herschel-based oscillator with a 12-digit-prime period, along very similar lines as the 11-digit-prime oscillators constructed in 2003, but with alternative 'glider advancer' technology and more compact connecting circuitry.

Like the 2003 examples, this pattern consists of a Herschel/glider loop (period 1536 this time, instead of period 1450) attached to a series of thirteen 'quadrupler' conduits of two different types, L-shaped and straight. Each quadrupler allows only one Herschel signal in four to get through to the next conduit.

In the starting configuration, the first three quadruplers are set to absorb three signals each: an extra block has been added to the first two L112 quadruplers and the first Fx70 quadrupler, which has a standard F166 dependent conduit appended to suppress the following Herschel's first glider. So the circuit initially counts down from 63. When all circuits are empty, a signal gets through to activate the 263-step glider advancer -- after which the circuit counts down again, this time from 4^13-1.

As usual with this kind of Herschel-track construction, Karel Suhajda's 'Hersrch' search program was used to design the base loop, and to locate an efficient connecting circuit between the end of the quadrupler chain and the glider advancer. The continuing challenge, of course, is to fit an oscillator with a higher prime period into a bounding box with a smaller number of cells.

Posted by Dave Greene at 02:14 | Permalink

Here's another batch of puffer orbits found by Jason Summers.

In the following tables, the percentages are approximate, intended to illustrate how common or rare a particular puffer might be. The bit patterns are not the actual puffer, but a simpler pattern which will eventually evolve into the puffer.

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The first puffer presented here is a based on a large Period 3 which moves at a speed of ^c/₃. It also has a slightly smaller Period 12 variation.

P222+102	≈97%
P114+3	≈3%
306P3H1V0	0.04%
P273+130	0%
P180+161	0.005%
450+239	trace
304P12H4V0	trace

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The next set of puffers are based on a Period 28 Spaceship.

213P28H7V0	99.94%
140+90	0.04%
P168+109	0.02%
P56+14	trace

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Another pair of puffers are based on a Period 2 Spaceship previously used to create a Period 8 Glider rake, both of which are shown also.

P224+124	99.98%
P32+7	0.02%

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The final set includes a previously known B Heptomino based Tub puffer.

P24+4	99.87%
P12+7	0.13%
P2724+4153	0.02%

Posted by HKoenig at 20:29 | Permalink

Nicolay Beluchenko has found a new Period 15 Oscillator which is based on a pair on interacting T-Tetrominos stabilized by sparks from 4 Period 3 Oscillators. A number of phases of the T-Tetromino pair resemble phases of the Pentadecathlon whose halves have been separated by a column.

Posted by HKoenig at 20:15 | Permalink

Thanks to John Green for pointing out that a number of the RLE files in the Puffer Orbits would not download properly. In fixing the problem and reviewing other possible problems, I found several other bad links. Please let us know when those things happen. If you can't see the images, or get and run the RLE files, then a mistake was made and it needs to be fixed. Or you may be using a combination of browsers and operating systems with which we are unfamiliar and may not realize we are breaking.

Posted by HKoenig at 20:00 | Permalink

Bill Gosper and Nick Gotts set some new records back in March, for patterns exhibiting quadratic growth starting from the smallest initial population. On March 11, Bill Gosper produced the starting configuration shown at right, which is closely related to patterns from his previous Golly experiments.

A week later, based on this, Nick Gotts produced a 26-cell quadratic-growth pattern: a forward-glider-producing switch engine repeatedly overtakes a crystal formed by collision with sideways gliders produced by a c/12 rake assembly. When the switch engine reaches the crystal, a reaction produces a orthogonal block-laying switch engine and restarts the crystal production at the c/12 rake boundary.

Here is what the 26-cell pattern looks like after ~3.5 million generations:

Posted by Dave Greene at 15:35 | Permalink

Nicolay Beluchenko created some sample diagonal greyships in various shapes, with a "grey" level of 1/3 ON cells (instead of the usual 1/2 for orthogonal greyships with 'stripes' or 'chicken-wire' agars.) Since these new "ships" are really an independent series of tubstretchers and tubeaters packed together as closely as possible, it's obviously possible to move the pieces farther apart from each other to produce lower fractions of ON to OFF cells.

It may also be possible to construct extensible multi-tubstretcher and multi-tubeater spaceships that support this agar -- where each stretcher or eater is connected directly to the next one, and can't be separated -- but this has not been accomplished as yet. Multistretchers and multieaters with wider spacings have been previously posted, however.

Tubstretcher-based patterns composed of more than 1/3 ON cells are not possible. Thus, to produce a diagonal greyship that maintains a 1/2-ON agar, it would be necessary to devise diagonally moving extensible patterns that stabilize the edges of some other type of agar -- either an oscillating agar, or an extensible series of waves (moving wicks), or perhaps an orthogonally symmetric stable pattern -- most likely the 'stripes' agar.

However, since the stripes are not diagonally symmetrical, each of the edges would need a different type of support. Whether such a construction is possible is currently an open question. The main problem is that diagonal spaceships could not repeat at period 4, because each stripe is two cells away from the previous one -- so p8 spaceships would be needed.

Unfortunately p8 is not really within reach of currently available Life search programs (mainly David Bell's 'lifesrc' and Jason Summers' ' WinLifeSearch' port). Some fairly large leaps in efficiency and/or CPU speed would be needed to make this a likely goal. [Readers are, of course, invited to prove this statement wrong -- or to supply the necessary advances in search technology.]

Posted by Dave Greene at 04:12 | Permalink