Pattern of the Year 2016 (Entries)

[Kazyan]

I'm not sure what the "new reflector mechanism" is, but I think it's referring to bumpers. Could you clarify, Alexey? If that guess is correct:

New reflector mechanism: When building circuitry and guns, a central problem is to get a glider to the correct location at the correct time. The builder usually ends up wrangling with the glider's color and its phase mod 4 or 8, with no guarantee that snarks and figure eight reflectors can solve the problem compactly (or at all). But now a periodic color-preserving "bumper" is available, and its output gliders fall 5 ticks behind those of a snark. It's also not very picky about its sparker, so it works all the way down to p4. This solves various "my glider is in the wrong phase" wiring problems, and a small wave of record-breaking guns followed soon after it.

[dvgrn]

I'm not sure what the "new reflector mechanism" is, but I think it's referring to bumpers. Could you clarify, Alexey?

Along the same lines, I can't really think of anything for "new gun periods". The really impressive Github project that chris_c has been administering got its start way back on Mar 22, 2015, and it has never added any new gun periods -- just set new records over Jason Summers' comprehensive p14-p999 collection, which in turn was an improvement on Dietrich Leithner's and Peter Rott's less comprehensive collection.

Certainly we set some more records in 2016, but I don't know which periods would be considered new. Some of the exotic spaceships picked up guns of new periods, I suppose...?

[Sokwe]

I can't really think of anything for "new gun periods".

It refers to the p57, p58, and p61 guns posted in this thread. No true-period guns of these periods were known until last year. In fact, you linked to the p61 gun in your description of the compact stable Herschel splitter.

[dvgrn]

I can't really think of anything for "new gun periods".

It refers to the p57, p58, and p61 guns posted in this thread. No true-period guns of these periods were known until last year.

Ah, of course! Thanks for the reminder. There are still quite a few unknown periods for the true-period gun collection, but I guess most of them will have to wait until someone comes up with a fast-recovering signal splitter of some kind.

Grandfather problem:
On May 5th, mtve solved the grandfather problem, with a 298-cell pattern. This was one of the longest-standing open problems in Life, having been unsolved in spite of a $50 prize offer from John Conway Himself in September 1972. Solutions to the "great-grandfather problem" and the "great-great-grandfather problem" soon followed.

Small GoEs:
On September 16, 2016, Steven Eker set a new record for smallest GoE with Garden of Eden 10, a 55-cell GOE in a 9x11 bounding box; the non-convex orphan pattern has only 89 cells. There's a "Garden of Eden 8x12" also found by Steven Eker back in April, as also documented on Achim Flammenkamp's website. See also the record-breaking 5-cell-high GoE in the first link above. Apparently Eker has proven that there's no such thing as a 3-cell-high GoE, but the 4-cell-high case is still an open question. See Achim's website again, for the only details on this that I can find anywhere.

[dvgrn]

If everybody is lazy, I will add a few more descriptions myself, but I hope for your help.

I think we haven't been too lazy. Looking back, I think this is the last remaining description:

15-bit SL syntheses: On 9 October 2016, GoldTiger997 announced a goal of finding ways to synthesize all 15-bit still lifes using less than 15 gliders. This turned out to be one of the most prolific and successful collaborations of 2016, using many new Catagolue soup-search results along with combinations of Bob Shemyakin's, Mark Niemiec's, Chris Cain's, and others' known and new converter mechanisms. Several hundred new syntheses later, the goal was achieved in just 41 days. It also prompted new interest in automated analysis of glider syntheses.

[Alexey_Nigin]

Thank you all. I will compile the descriptions in a couple of days.

[Sokwe]

Should the credits for the discoveries be displayed more prominently? Currently it seems that the credits are buried inside the description paragraphs.

Also, I was remiss in not nominating Dongook Lee's new honey farm oscillators (link 1, link 2, link 3). Dean Hickerson's new p11 oscillator, rattlesnake, probably also deserves a mention, since it is now the smallest known period-11 oscillator.

Looking back, I think this is the last remaining description

We also still needed a description of the new gun periods:

New gun periods (by Luka Okanishi, "thunk", Matthias Merzenich, and Chris Cain):
From April 13 to April 15 2016, true period guns for three new periods were discovered. On April 13 2016, Luka Okanishi posted a true-period p61 gun, the first of its kind. It used two new reactions: a glider-to-Herschel converter that utilizes the spark of a LWSS, and a Herschel-to-2 glider converter that works at period 61. The next day, Chris Cain found a different p61 glider-to-Herschel converter based on a suggestion by Adam P. Goucher, and he used this to build a new type of p61 gun. Later that same day, Matthias Merzenich used the ideas presented in this new gun to find G-to-H and H-to-2G converters that work at p58. "thunk" used these components to construct the first true-period p58 gun. The next day, Dongook Lee suggested that a p3 sparker might be able to liberate a glider from an Fx77 conduit in the p57 Herschel loop. Matthias Merzenich found a working p3 oscillator about an hour later.

[Sokwe]

Statorless p5: A very notable thing of this discovery is that the oscillator is Strictly volatile. Strict volatility is a very tight restriction, with the only periods with strictly volatile oscillators being 1, 2, 3, 5, 6, 8, 13, 15, 22, 30, 33, and 177. The latest strictly volatile oscillator "seems to be" (confirmation needed) derived from 34P13 on 2009. This means that this discovery adds a new period in 7 years. This is also the second statorless oscillator of a prime period greater than 2. (The first being the 34P13 derivative.)

The most recently discovered strictly-volatile oscillator period (besides p5) is p3, discovered by Jason Summers in August 2012. This makes p5 the third prime period greater than 2 with a known statorless oscillator.

[Alexey_Nigin]

I will compile the descriptions in a couple of days.

Under a reasonably relaxed definition of a couple of days, I compiled the descriptions:

http://conwaylife.com/forums/viewtopic. ... 635#p39635

Any feedback is welcome, including one about minor things like typos. I would especially appreciate if you told me whom I should credit for 15-bit SL syntheses.

The voting thread will do live on the GoL day, 23/3, unless I miss a self-imposed deadline once again.

[Sokwe]

I would especially appreciate if you told me whom I should credit for 15-bit SL syntheses.

I would credit it as
BlinkerSpawn, Goldtiger997, Bob Shemyakin, Mark Niemiec (mniemiec), Martin Grant (Extrementhuiast), Chris Cain (chris_c), et al.
with the alii being Tanner Jacobi (Kazyan), Luka Okanishi (AbhpzTa), Matthias Merzenich (Sokwe), Alexey Nigin, yootaa, and gmc_nxtman.

[simsim314]

I just remembered that Chris and Adam had built a constant cell count universal constructor, I think it was 2016 as well wasn't it? The idea was to code the operations tape by just using a distance of far away SL, I think it's a brilliant idea...

[dvgrn]

I just remembered that Chris and Adam had built a constant cell count universal constructor, I think it was 2016 as well wasn't it? The idea was to code the operations tape by just using a distance of far away SL, I think it's a brilliant idea...

The base-3 converter pattern in question was posted in 2015. I don't consider it quite finished yet, since we don't have a construction recipe for it. If the idea gets rebuilt in Spartan P1, I think Calcyman's slow-glider-pair compiler or his new slow-salvo compiler could produce a recipe automatically.

Then once we came up with some specific glider salvos to destroy the final state of the converter/constructor, we'd know an actual maximum value for N, the number of gliders needed to construct any glider-constructible object. I'd certainly vote for that for Pattern of the Year 2017!

EDIT: With the new compiler, the base-3 converter doesn't even have to be Spartan -- syringes and well-separated Snarks are handled quite nicely. The resulting recipe will have a lot more gliders in it than strictly necessary, though, probably giving a 5-digit upper limit N instead of a 4-digit value. Probably it's cheaper to turn the current p690 version into a Spartan seed pattern, and then build that either manually or by compiling with Calcyman's old 2-arm recipe compiler.

[simsim314]

The base-3 converter pattern in question was posted in 2015.

OK so it's not 2016 discovery...

Then once we came up with some specific glider salvos to destroy the final state of the converter/constructor, we'd know an actual maximum value for N, the number of gliders needed to construct any glider-constructible object.

As this pattern is "glider destroyable" we don't need to add self destruct - the destruction can be simply part of the dried salvo coded inside the tape. I don't think we need to "prove" this pattern is glider destroyable, as I think it's self evident.

[dvgrn]

As this pattern is "glider destroyable" we don't need to add self destruct - the destruction can be simply part of the dried salvo coded inside the tape. I don't think we need to "prove" this pattern is glider destroyable, as I think it's self evident.

Good point. Added this quote to the new thread on the fixed-cost decoder/constructor.