## 2D: Magnetically Levitated Oxcart?

Ideas about how a world with more than three spatial dimensions would work - what laws of physics would be needed, how things would be built, how people would do things and so on.

### 2D: Magnetically Levitated Oxcart?

2D is difficult, because a wheel can't have an axle. At first one might think that the wheel is impossible and that only rollers would be available. But there may be a way. Magnetism. Maybe.

If magnets exist in 2D, then they could be used to make wheels. A wheel is a round magnet. It fits into sort of a socket in the bed of the oxcart, which is magnetized with the same polarity. The poles repel one another and via magnetic levitation one has a comfy oxcart with built-in suspension.

BUT magnets don't have poles in 2D. Indeed, magnets have true poles only in 3D. Magnetic polarity and magnetic poles are not all that useful of concepts in other dimensions. Instead we have magnetic planes. Magnetism is planar.

2D is unique (I think) in that magnetism is chiral. There are right-handed and left-handed magnets. Right repels right and attracts left. Permanent magnets cannot flip over, so there is no easy way to change right to left. All this seems ideal for oxcarts. Confined to the 2D plane the wheel can never fall over. If it is also confined to a socket then there is no need for an axle. All we need to do is to avoid friction. Magnets of the same chirality repel one another, so we could have magnetic levitation with no friction and very little energy loss. What could go wrong?

What could go wrong is that maybe there is no way to make a permanent magnet in 2D. According to Richard Feynman, permanent magnets depend on the quantum spin of electrons. A permanent magnet is made by aligning the spin of electrons in iron or some such material. If our electrons are 2D, how do we know we can flip them over? Isn't that forbidden?

Well, maybe yes and maybe no. As far as anyone knows, electrons are zero dimensional. They have no size. Their spin comes with only two possible values, 1/2 or -1/2. All this is a mystery that even Feynman dared not attempt to explain. So... could they flip over in 2D?

An electron can exist with its spin in an undefined state of quantum superposition. But inside a magnet the spin is defined. Is it reversible in the context of 2D iron? Hard to tell, hard to tell.
PatrickPowers
Trionian

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Joined: Wed Dec 02, 2015 1:36 am