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Discovery of a new irregular pentagon that can cover the plane

theguardian.com

31–40 of 131 posts

Re: Discovery of a new irregular pentagon that can cover the plane

#31
It's interesting how your eye naturally groups the pentagons into the larger primitive unit, like the pinwheels of type 5.

Wolfram Alpha also has some things about tiling: http://www.wolframalpha.com/input/?i=pentagon+tiling http://www.wolframalpha.com/input/?i=pentagon+type+5+tiling

Re: Discovery of a new irregular pentagon that can cover the plane

#32
post #9

This is cool, but I'm not sure why it's a hard problem to solve for a computer running through a ton of 5-sided polygons with some basic rules and attempting to tessellate them? Is there a reason that approach doesn't work, other than being rather un-romantic as far as discovering cool new things like this goes?

That approach does work. From the article: "We discovered the tile using using a computer to exhaustively search through a large but finite set of possibilities,” said Casey.

Right? I love when people ask "Why don't they do X?" without even bothering to read the damn article. Does the parent think that people just randomly stumbled upon this shape?

Re: Discovery of a new irregular pentagon that can cover the plane

#34
Many of these types are basically combining two pentagons into an octagon (or even hexagon) then tiling it across the plane. For some reason, intuitively those seem more easy to me (2 * 3, 2 * 4), so that you could just generate a bunch of them, and split them in two to create tessellating pentagons?

Even the example in the article can be viewed as a regularly tessellating nonagon. I don't see what's "irregular" about it? The article doesn't mention that word, but the HN title does.

Re: Discovery of a new irregular pentagon that can cover the plane

#35
post #11
post #10

I think it's kinda funny that most of the tessellations are just using pentagons to make other shapes that tessellate naturally. I suppose the same could be said of most tessellations though, but it's still interesting.

That's because there are only 17 wallpaper groups ( https://en.m.wikipedia.org/wiki/Wallpaper_group ). Any _repeating_ pattern must match one of them (non-repeating patterns by definition do not)

Can you NOT link to mobile version? Mobile phones switch to mobile automatically, desktop version does not.

Re: Discovery of a new irregular pentagon that can cover the plane

#36
post #29

Earlier quoted context omitted.

I don't think that tiling a plane is exactly a "simple" problem.

I mean something simple enough to understand, and could be played by average programmer in a IPython Notebook. I didn't mean simple to solve, just lower barrier of entry.

I like this one:

http://www2.stetson.edu/~efriedma/squinsqu/

Can be easily generalized to other shapes and more dimensions too.

Re: Discovery of a new irregular pentagon that can cover the plane

#38
post #21

Perhaps the more impressive number is that they found 7 quintillion new irregular pentagons that can't tile the plane.

I've read your comment a few different ways. I'm concluding that you find it impressive that it took 7 quintillion tries to find a new pentagon that can tile the plane.

I think he just meant that the number 7 quintillion is an impressive number, more than 15.

Re: Discovery of a new irregular pentagon that can cover the plane

#40
post #39

Besides tiling your bathroom is there any use case for this? Or is this pure for fun and gaining knowledge? Edit: The article is talking about building structures but isn't a triangle the most rigid form? And triangles are already used in building.

Should it be discounted if it were done for pure fun?
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