Magnetic artificial gravity

Hi all,

I'm really sorry, but it seems that I'm undergoing one of my "thought
crisis", when I can't stop thinking about something until my brain melts
down and stop working. Writing about what I'm thinking helps to end that...
And this mailing list is the appropriate place to write about that.

It is another wacky idea associated with unconventional uses for magnetic
fields. This time, I'm thinking of an alternative for centrifugal gravity:
magnetic gravity.

The common notion that organic tissues do not interact with magnetic fields
is false. In fact, our flesh and bones and fluids do interact with
magnetism, but the interaction is about 10,000 weaker than that obtained
with iron. Also, the effect is the opposite of the one occurring in iron: it
is a *diamagnetic* effect, where the molecules align themselves in order to
counteract the magnetic field; that is, our tissues are *repelled* by
magnetic fields, instead of being attracted.

If you have a strong enough magnetic field, you can make funny things like
counteracting the gravitational force and making a living being levitate in
a "magnetic cushion". There are actually experiments were small animals,
like frogs and locusts, are levitated in 16T fields.

Well, by doing something like that in space, you could magnetically push
your frog or locust against a surface with the same force or the weights
that they would have on Earth. In other words, you could use the magnetic
field as a substitute for the gravitational field. Supposing that we are
able to build a huge magnet (probably superconducting) over a city-sized
structure in space (or in the surface of a low-gravity world like Moon),
people living in this city would be pushed against the floor in the same way
that gravity would do on Earth.

This magnetic gravity would have the advantage of not requiring you to spin
your whole colony; also, probably the magnetic field would be strong enough
to work as an active radiation shield.

On the other hand, life for people inside this city would be very strange.
There would be virtually no objects with iron or other ferromagnetic
materials. (On the other hands, you could make levitating objects and
vehicles by just adding iron in their composition, providing "magnetic
buoyancy".) Also, it would probably be a pain in the ass to put this thing
in orbit around a world with magnetosphere, like Earth.

I think that this idea is not exactly new. I remember that Asimov always
referred briefly to diamagnetism to explain artificial gravity in the ships
of his SF books. However, I would like to discuss the pros and cons of the
idea anyway...

Lucio