Do you tie your lures and flies on with a loop knot? If you answered no, don’t fret. I can’t tell you how many anglers I’ve met that don’t incorporate a loop knot into their repertoire of ties. I ...

From Simons Science News (find original story here). The mathematics of knot theory says that a simple loop and a trefoil are fundamentally different knots. But is that all there is to the question?