- #1
Hornbein
- 2,070
- 1,694
In a 4D Euclidean Universe knives and swords come in three types -- 1D, 2D, and 3D.
Knives have to be at least 2D, since a 1D knife can't cut anything in two. A 2D knife edge! It took days before my feeble brain could be convinced such a thing was possible. You could start with a steel rectangleoid with two large dimensions and two small, then hammer the two small into the shape of an acute triangle. The two long dimensions don't have to be the same but both have to be longer than the diameter of whatever it is you want to sever.
Even those cheese cutters made out of wire have to have 2D wire. Weird! We know this because a 1D knife separates a 2D plane. A 2D plane doesn't partition a 4D solid. The knife has to produce a 3D plane.
Butter knives are 3D, since they are spreading butter on a 3D surface. They can still cut the butter.
Epees and rapiers -- thrusting weapons -- are 1D and hence pretty much the same as in our 3D world. It is however not practical to parry a slashing blow with a 1D blade.
Knives have to be at least 2D, since a 1D knife can't cut anything in two. A 2D knife edge! It took days before my feeble brain could be convinced such a thing was possible. You could start with a steel rectangleoid with two large dimensions and two small, then hammer the two small into the shape of an acute triangle. The two long dimensions don't have to be the same but both have to be longer than the diameter of whatever it is you want to sever.
Even those cheese cutters made out of wire have to have 2D wire. Weird! We know this because a 1D knife separates a 2D plane. A 2D plane doesn't partition a 4D solid. The knife has to produce a 3D plane.
Butter knives are 3D, since they are spreading butter on a 3D surface. They can still cut the butter.
Epees and rapiers -- thrusting weapons -- are 1D and hence pretty much the same as in our 3D world. It is however not practical to parry a slashing blow with a 1D blade.
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