VbvAstE-001

Chapter 12
The Theory of Earth
12.1 The introduction
Seismic measurements show that as the depth grows, the density of the Earth’s matter
increases at first more or less monotonically. However, on the core-mantle interface
it rises abruptly. There exist a series of Earth models [23],[24] for the description of
the density growth, for the explanation of the reason of the separation of the Earth
matter into the core and the mantle and the determination of the density jump on their
interface. Quite separately there exist models for the explanation of the origin of the
terrestrial magnetism. Among these models, there is one based on the hydrodynamic
hypothesis. It was developed in the 1940’s-1950’s. At present it is generally adopted.
All these models try to decide the basic problem - to obtain the answer: why the main
magnetic field of the Earth near the poles is of the order of 1 Oe? Such statement of the
basic problem of terrestrial magnetism models nowadays is unacceptable. Space flights,
started in 1960’s, and the further development of astronomy have allowed scientists
to obtain data on magnetic fields of all planets of Solar system, as well as some their
satellites and a number of stars. As a result, a remarkable and earlier unknown fact has
been discovered. It appears that the magnetic moments of all space bodies (those which
have been measured) are proportional to their angular momenta. The proportionality
coefficient is approximately equal to G 1/2 /c, where G is the gravitational constant, c
is the velocity of light (fig.7.1).
Amazing is that this dependence remains linear within 20 orders of magnitude!
This fact makes it necessary to reformulate the main task of the model of terrestrial
magnetism. It should explain, first, why the magnetic moment of the Earth, as well
as of other space bodies, is proportional to its angular momentum and, second, why
the proportionality coefficient is close to the above given ratio of world constants. The
aim of this paper is to show that it is possible to construct the theory of the Earth
using the full energy minimization method. This theory allows us to apply a new
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