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@SomaticCustard I've seen étalé bundles in various introductions to sheaves, and sometimes the word étalification is used. But I can't remember anywhere that explicitly treats them as comonads.
@MarkS If you squint a bit, you can see that the red, yellow and green tiles form hexagonal grids with the same angle and spacing, while the blue tiles form a hexagonal grid with a different angle and larger spacing. My guess would be that the constants relating the two grids are irrational, killing any wallpaper group.
Jesse Clark has the same colouring here: twitter.com/myhf/status/1639053012399439872. They didn't notice that the flipped tiles are all the same colour, but did point out that four tiles meeting at a point all have different colours.
Is it possible that there is some other (necessarily also aperiodic) tiling of the plane by this tile that is three colourable? Or must every such tiling contain the above configuration?
