Message #3305

From: Melinda Green <>
Subject: Re: [MC4D] AlphaGo, 4D Go, Hyperbolic Go
Date: Wed, 09 Mar 2016 16:30:25 -0800

It was indeed exciting, and I’m even going to predict that it was a game
that will be remembered by history in much the same way as the pivotal
chess game in which IBM’s chess bot Deep Blue beat the world champion
Gary Kasparov with a move so brilliant that he was convinced they had
cheated. This first of five Go games contained what appeared to me to be
a similarly devastating move by the machine. Here
<> is the video capture of the live
event. It’s really ragged at the beginning as I don’t think Google was
prepared for all the watchers but it gets better over time. Game
commentary is provided by a wonderful expert, Michael Redmond, who plays
at a similarly high level and he also explains a lot of basic concepts
though you can easily find many other great places to quickly learn the
basics if you are interested.

I’ve played one 13x13 game of Go on a torus and a another on a cylinder,
and they were very interesting. The problem with the torus, and perhaps
other polytopes, is that the lack of borders and corners leaves you
feeling rather naked as all territory must be built in empty space. It
was an equally strange experience going back to a normal board after
just one small game on a torus. I’m not sure how to describe the
experience but I’ll just say that it hurt my normal game for a
surprising amount of time.

My game on the cylinder was a little more interesting to me. I think it
becomes natural for each player to sort of stake out one end, and then
to create rings in the middle in such a way as to capture opponent’s
rings. You need to understand a bit about the game to understand this
but it seems to naturally come down to what are called capturing races.
I think that playing on a torus might work well if non-square dimensions
are chosen such that these sorts of rings become important but not too

Go variants played on boards with different vertex valences have been
tried but I get the feeling that 4 really is the best choice. So Roice
may be right that a {5,4} would make for an interesting choice since it
preserves the familiar vertices. I don’t think that infinite boards will
be attractive, but finite ones with negative curvature might work though
the lack of borders and corners might be even worse than on a torus.

MagicTile could be an ideal platform for testing out some of these
ideas. There is a small but passionate population of Go players who
enjoy exploring non-standard boards and would certainly love this idea.
I like the idea of playing on the skeleton of duoprisms though I think
the particular choice of duoprism will be very important to how well it
adapts to the game. If you implemented this, would it still work in the
3D view? As we’ve seen with the IRP puzzles, the 3D view was not helpful
but it sure looks great and helps to explain the topology. As with the
duoprisms, I suspect that the particular choice of IRP would be important.

If you’re seriously considering integrating Go into MagicTile, I suggest
contacting some of the people in the Go community who like to play on
non-standard boards to find out what excites them the most.


On 3/9/2016 9:38 AM, Roice Nelson [4D_Cubing] wrote:
> Anyone catch the match last night? Melinda and I did, and are
> enthusiastically discussing it. It was awesome! You can watch the
> remaining games live here
> <>.
> To connect the excitement back to the group, I wanted to mention you
> can play Go on the 1-skeletons of 4D polytopes using an early version
> of Jenn3D. Head to the very bottom of this page
> <> to try. Duoprisms are
> particularly interesting, because you can use them to make boards that
> remove all the edges of a traditional board but are otherwise the
> same. Playing on polytopes feels like it would generally have too
> much freedom though, especially if single stones have more than 4
> adjacent liberties.
> Adapting MagicTile to support Go might work well, since it would keep
> the boards as 2D surfaces. A {5,4} tiling would be a natural choice
> for a first board, and probably some of Andrea Hawksley’s ideas about
> non-euclidean
> <> chess
> would apply. But I also wonder if hyperbolic Go would be
> fundamentally flawed. Random walks in the Poincaré disk inevitably
> escape to infinity. For this reason, it is almost impossible to heat
> a house in the disk because you can’t stop the heat from escaping (p37
> of the book The Scientific Legacy of Poincare
> <>).
> I wonder then if it would similarly be almost impossible to surround
> territory in hyperbolic Go. We need to try this!
> Roice