Evidence of Gravitomagnetism

Saturn's rings

Gravitomagnetism on a classical scale has been overlooked for the most part. Wallace and others have explored Gravitomagnetism and it isn't quite as obvious as electromagnetism.

The LAGEOS series of experiments reported measuring orbital precession due to gravitomagnetism. Saturn's rings may be evidence of gravitomagnetism as well for similar reasons. One doesn't need to know the permeability constant ? to see the form of gravitomagnetism at work in nature. From the analogy with electromagnetism, we should expect a torque aligning the spin of Saturn with its rings and maintaining that alignment, which is what we see in the beautiful rings aligned with the features of the planet.

There is an L x B torque term of one ring's angular momentum L interacting with the gravitomagnetic flux density B of the rest of the rings as well as Saturn itself. We see that the rings have settled out in the spin plane of Saturn where there is no torque.

Forget the mathematics for a while and observe the beauty of nature. All the years of toil to understand the mathematics is rewarded with the understanding of the nature of one of the most beautiful sights in the solar system. Even if you didn't study the mathematics, you probably played with magnets as a kid and noticed that they lined up north pole to south pole. When you tried to stick two north poles together, they wouldn't stick without superglue, would they? This is a similar sort of thing.

Qualitatively, any first-grader could understand this. That is the beauty of it, for all to see.  It really doesn't matter what the exact value of ? is to appreciate beauty. Artists should be able to understand the nature of the rings without signing up for calculus.

Consider the Barnett effect of magnetizing a material by spinning it. This is a form of gravitomagnetism. On a astronomical scale consider the terrestrial magnetic field. For a spherical core of iron spinning with respect to the bulk of the universe,

B is ? and H is ?/? for the vacuum region outside the sphere.

M is ?H inside the iron and indications so far suggest paramagnetic behavior rather than ferromagnetic behavior.

Outside the iron, the boundary conditions require the flux density normal component to match at the pole. Usually a geometrical factor of 3 comes into play due to the demagnetization factor of a sphere (Nd=1/3). All terms signify gravitomagnetic parameters.

While there are uncertainties in the values of some of these parameters, it is likely that the terestrial magnetic field has a gravitomagnetic source component. The regular magnetic moments have a linear relationship with their gravitomagnetic or quantum mechanical analog. Nuclear spin may be as important as electron spin moments in gravitomagnetism, while it is ignored for the most part in electromagnetism.