When I was researching geospace, I found that the radiation belts known as the Van Allen belts are torus-shaped. A torus is a ring-shaped rotating object made by rotating a circle, and the most typical shape is a donut.There are many things in nature that are torus-shaped, and even in geospace, the radiation belt, magnetosphere, plasmasphere, oxygen ion torus, etc. seem to be distributed in a doughnut shape. Like a magnet, there are north and south poles that are separated, and the movement of the force that attracts each other probably creates a torus shape.
It seems that schools of fish also sometimes swim in a torus shape. When they swim around a certain area, they probably form a doughnut shape when they rotate in a three-dimensional school. Toruses may appear in organisms that swim underwater or in fluids such as water.When a fluid moves as if it were confined to a box of a certain size, the most natural shape for it to move would be in the shape of a torus, so that it can rotate left and right and also up and down.
https://www.jstage.jst.go.jp/article/jpsgaiyo/72.1/0/72.1_3165/_article/-char/ja
There also seems to be a phenomenon called torus convection, where water convects in a torus shape. When a container of water is heated by a candle, the hot water moves up the center of the container, and when it is cooled by the surface of the water, it moves down the edge of the container, resulting in a donut-shaped convection movement.In a closed space, convection in the shape of a torus may be natural if the central part moves upwards or downwards.
https://repository.kulib.kyoto-u.ac.jp/dspace/handle/2433/83349
There are also other fruits that are torus-shaped. They don’t have a hole, so they’re not doughnut-shaped, but apples and cherries have a concave top and bottom to give them a torus shape.The rachis cavity is hard to support the weight of the fruit, the calyx cavity seems to harden as the sepals close after the flowers bloom, and the rest of the fruit swells from the inside, so it is thought to be torus-shaped with depressions at the top and bottom. After peeling, the flesh of a mandarin orange also looks torus-shaped. The torus shape may be formed when two fixed points of some kind are combined with a part that swells freely.
https://www.g-de-b.com/matome/2016/10/04/post-9625
It seems that even in the quantum and molecular world, torus shapes can occur, and one of the d orbitals, which indicate the probability of the existence of electrons around an atomic nucleus, is doughnut-shaped. Also, a protein called a DNA clamp, which promotes DNA replication, is also doughnut-shaped. The doughnut shape is also called a toroid.
https://www.tohoku.ac.jp/japanese/2017/05/press20170526-03.html
I have looked into the torus shape in the world of magnetic fields, fluids, fruits, electron orbits, and molecules. There seems to be some meaning behind the shapes that appear in both the macro and micro worlds. The torus that appears in various phenomena is amazing. The mysteries of the Earth are amazing.
