If we read about the structure of this planet, we are assured that the flattening at the polar regions is caused by centrifugal force acting outwardly at the equator to give a somewhat elliptical shape. The difference in polar and equatorial diameters is quite substantial, at about 100 miles. This theory relies on the assumption that the Earth's mantle is molten or at least plastic, which it probably is.
Books on gravity, however, give two predominantly opposing viewpoints regarding centrifugal force. Some writers believe that centrifugal force does not exist on a planetary scale, because of the impossibility of reconciling it's variable nature, that is,100% at the equator, and virtually zero at the poles. The other camp believe that gravity cancels out the effects of centrifugal force, and choose to simply disregard the variability factor.
It is possible that all three views may be correct. Centrifugal force may well be present and acting on us in a variable manner. This would require an opposing force, also acting in a variable manner. I suggest that the Earth's slightly magnetic, rotating crust, is supplying this force.
The rotation is creating the Earth's magnetic field, or
Dynamic Gravitational Field, which, on the dark side of the planet, extends an enormous distance, but where it meets the Sun's magnetic field it extends only a short distance into space. Where the two magnetic fields meet they appear to interact, and to generate another field, this one the high voltage electric currents which are known to exist in an area of the upper atmosphere.
The area of electric currents in the upper atmosphere is reported to carry voltages ranging from billions of volts to about 250,000 volts. The surface area has high voltage static electricity at about 20,000 volts. It seems quite feasible that this voltage is flowing through us, as it flows towards a lower voltage somewhere in the interior of the planet. As long as a body is at the ambient atmospheric voltage, it will be attracted towards the center of the planet, in addition to the normal static gravity, thereby overcoming the repelling effect of centrifugal force.
This voltage would be at it's highest at the equator, where the planetary rotational velocity is at it's greatest, diminishing gradually to zero at the polar regions.
This electric field must also be shielding surface objects, us, from the gravitational pull of the Sun and the Moon. This electric field in the atmosphere is the only possible source of shielding from the Solar and Lunar gravity. If we can make a machine which duplicates this electric field, then we may be able to shield ourselves from the Earth's gravity.
Diagram of Fields