Hey, I saw that post about the trefoil knot in your icon. What's so special about it? Googling only brings up math stuff I don't really understand.
Hey, thanks for asking! Basically, it’s important because a trefoil knot is the simplest knot there is. If you take one piece of string, make one loop in it, and put one end of the string through that loop (then join the ends), that’s a trefoil knot. Its simplicity makes it, like, Knot Number One, a keystone of knot theory. That is why it’s important in knot theory.
If you want a wee bit of background - the Victorians had a theory about the (a)ether - very very roughly the 19th century’s answer to dark matter. they thought the ether was a substance which filled the universe, and everything in the universe was suspended in the ether. A bunch of Victorian scientists, including our boy Lord Kelvin, thought that atoms were knots in the aether. He and his pal Peter Guthrie Tait, and their other mate James Clerk Maxwell came up with a bunch of different knots of varying shape and complexity. Tait (who is my fave - the exact trefoil in my icon is from the cover page of one of his books) came up with a kind of periodic table of knots. The trefoil knot therefore kind of equates to the hydrogen atom - the simplest knot in the ether forms the simplest atom.
That was kind of the peak of knot theory - once ether stubbornly refused to reveal itself in experiments the whole thing went out of fashion, but knot theory is still a bit relevant in quantum physics and for modelling/understanding some stuff like DNA andcertain types of molecules.
So that’s what’s so special about the trefoil knot.