Tuesday, May 1, 2007

How Gravito Magnetism is Different from Electro Magnetism

Electromagnets can be created by electric current flowing through the magnetic wire wound around a metallic cylinder. The direction of the current determines the polarity of the magnets. So the direction of the movement of the charge is crucial to the determination of the polar properties of the magnetic force.

On the other hand, in the gravito magnet case, the direction of the rotation is not a factor in determining the polarity of the poles. So the similarity stops here quickly.

The following statement provides us with the current insight into the gravitomagnetism. "Gravitomagnetism is produced by stars and planets when they spin. "It's similar in form to the magnetic field produced by a spinning ball of charge," explains physicist Clifford Will of Washington University (St. Louis). Replace charge with mass, and magnetism becomes gravitomagnetism" quoted from http://science.nasa.gov/headlines/y2004/19apr_gravitomagnetism.htm.

However, there is no observed gravitational phenomenon that indicates the dipole gravito magnetic effect from a rotating spherical object as a whole. Because if that is the case, we will observe the weaker gravity force in the north pole in comparison to that of the south pole or vice versa, which has never been observed. And also the jets from the black holes would have to be only from one pole not from the both poles as observed.

The asymmetricity of the object along the rotation axis determines the polarity of the gravito magnet. For example, a cone, a hemisphere, etc will produce a gravito magnet in rotation but a rotating cylinder will not. (This point has been discussed by Bass and Pirani previoulsy where they objected that Lens-Thirring force can not be the centrifugal force because a rotating cylinder also must have a non zero Lens-Thirring force, but it doesn't. However, one can always argue that the Universe is not a cylindrical shape.)

The wider area becomes the attractive pole and the sharp and narrower area determines the repulsive pole regardless of the direction of the rotation around its symmetry axis.

The reason a spherical rotor can create a quadrupole gravito magnet is because the asymmetricity of it changes at the equatorial plane ie the radius in relative to the rotation axis increases along the Z axis and then at the equatorial plane it starts to decrease, which means that it is an oppositely stacked two dipole gravito magnets. Thus, a rotating spherical object becomes a quadrupole gravito magnet in which the equatorial plane becomes the region where the attractive gravito magnetic poles are faced to each other.

The gravito magnetic force lines come out of the both poles and merge into the equatorial plane and then joined together to come back into the center and then go back out of the both poles.

Probably 99 percent of the rotating stellar objects, if not all, including the black holes in the universe may be described as a quadrupole gravito magnet in addition to the typical gravitational monopole. When the monopole gravity dominates the gravitational interaction, the shape of the object will most likely tend to become spherical. However, as the rotational motion starts to kick in, the general shape of the star will be more like an oblate sphere or a superposed saucer shaped disk which will in turn accentuate the gravito magnetic effect and accelerate the process of becoming a black hole with enormous jets.

Monday, April 30, 2007

Radial Component of Dipole Gravity Force in the Equatorial Plane

To calculate the length of the jets from the rotating sphere solely from the linearized theory, one can simply use the following potential.

To find the distance r that makes the above total potential zero on the domed side of the rotation axis using the fact that the maximum length allowed for the relativistic shift of the center of mass is R/2 where R is the radius of the sphere(see below diagram), the distance r that defines the length of the jets becomes barely an order of the radius of the sphere R.

http://www.tachyonics.com/9604044.pdf .

This is not enough to account for the observed length of the jets. There are many factors that may affect this outcome. The actual geometrical shape of the rotating center could be one of the main factors. If the galactic center is no longer shaped like a sphere but widely stretched disk shape in its solid structure, it will certainly affect the length of the jets in such a way that it extends further away from the center.

There could also be a significant contribution from the non linear effect that the linearized theory could not have taken it into account because the system will no longer be in the weak field regime.

At least for the time being, for the purpose of simulation as a cosmological model , one may have to use the dipole moment (mass times the center of mass shift) as a parameter that determines the strength of the jets. This may eventually help determine the actual geometrical shape of the galactic center.

The radial component of the gravito magnetic force around the equatorial plane in the above has M delta Rc dependency which is the major parameter in determining the length of the jets. Here, we can see that the experimental correlations can be made between the length of the jets and the parameters that determine the velocity curve in the dark matter problems of cosmology.