alt Hacker NewsIt seems to be the same kind of periodicity unless I'm missing something.
> Periodicity, for our purposes, is a repetition of relationships in specific intervals. Mendeleev had found that the elements were periodic based on the relationship between atomic weight and valency.
(from parent link)
Yeah, they're both about periodic repetition. But a periodic tiling repeats in its entirety, exactly, with a fixed period. The periodic table groups elements based on properties that repeat periodically, but the periods change as you move down the table. The tiling also has string of repeating patterns, like the elements, but a periodic tiling is something other than just that.