Yosemite bowline Yosemite bowline A Yosemite bowline is loop knot often perceived as having better security than a bowline. It has been pointed out that if the knot is not dressed correctly it can potentially collapse into a noose, however testing reveals this alternative configuration to be strong and safe as a climbing tie-in. A Yosemite bowline is made from a bowline with the free end wrapped around one leg of the loop and tucked back through the knot, a final round turn and reeve commonly known as a "Yosemite finish." The knot's security is enhanced by preventing the bowline capsizing to
Arf invariant of a knot if they are related by a finite sequence of pass-moves, which are illustrated below: (no figure right now) Every knot is pass-equivalent to either the unknot or the trefoil; these two knots are not pass-equivalent and additionally, the right- and left-handed trefoils are pass-equivalent. Now we can define the Arf invariant of a knot to be 0 if it is pass-equivalent to the unknot, or 1 if it is pass-equivalent to the trefoil. This definition is equivalent to the one above. Vaughan Jones showed that the Arf invariant can be obtained by taking the partition function of a signed planar