Physical States of the Earth's Core

1. The question, "Is the earth's core gas or liquid ?" has been discussed from the standpoint of statistical mechanics. It has been found that for each element there is a critical temperature, below which the liquid state is stable in the core and above which the gaseous state is stable and this temperature depends on the atomic number of the element. This temperature is named the critical temperature for that element. 2. The molecular viscosity coefficient of the core has been computed. In case the liquid core is stable, the coefficient is 10-2-10-1 poise, while it is 10-3 poise in case the gaseous core is stable. Moreover, it has been shown that we can estimate the temperature of the liquid core, if its composition is known, or, conversely, we can estimate the composition, if its temperature is known. 3. Using the theory of visco-elasticity, the attenuation coefficient of the core for seismic waves has been obtained. The result agrees with observations of seismic waves. 4. The electric and thermal conductivities have been obtained, using formulas of statistical mechanics. Following values have been obtained: electric conductivity: 2-4×103 ohm-1 cm.-1, thermal conductivity: 0.05-0.5 cal. cm.-1 sec.-1 deg.-1.