Let take a new look at relations F=Gm1m2/r2 and F= - dU/dx. .

And please remember that the speed of gravity force has limit, and gravity force moves with light’s speed as (in relativity).

Relation F= - dU/dx shows that there is a relationship between gravity force and potential energy. It did grow into habit that physicists consider to right side of above relation. This is a fact that U does change of a point (as high) to another point. Question is that changing of U has any effect on gravity field or no? Suppose an object moves upward the earth. Its potential energy does change. Does gravity force of earth change or no? We know gravity force resists with this movement and force doing push object toward earth. Object loses its kinetic energy. By consider the relativity kinetic energy has mass. When object’s kinetic energy does decrease, what happens for gravity force? We can say nothing and kinetic energy changes to potential energy.

I ask you please do not stop on the above conception. Suppose a solid object has mass m at high h. It falls toward the earth. It takes kinetic energy that gives with equation 1/2mv2=mgh in during falling. When object reaches to earth, its kinetic energy changes to other energies like heat or electromagnetic energy (by spark). Suppose when object stay on the surface of earth its mass is m (its mass at high h is equal on earth).

In during that object was falling, it did take kinetic energy equal 1/2mv2. Why did increase object’s kinetic energy? Cause gravity force did act on it.

Now take a new look at the left side of relation F= - dU/dx and remember deltaU=1/2mv2.

 In during that object was falling, gravity force converted to kinetic energy (by consider the relativity gravity force changed to mass).

So, gravity force has mass. In the other word gravity field is weakly mass. The movement of object (it was falling) is medium to conversion gravity force to energy and vice versa.

Blueshift and Redshift

When a photon is falling toward the earth, its kinetic energy increases same as other objects. So, the frequency of photon increases and changes to high frequency. Observer saw photon shifts toward the blue frequency. Gravity force converts to electromagnetic energy. A quantum of gravity force (graviton) is that does change the photon’s frequency from f to f+1.

When photon is moving upward the earth, its frequency shifts toward the red. Suppose a photon does form on the surface of a black hole. Photon is unable escapes of its gravity field. Photon shifts toward red and gradually all of photon’s energy converts to gravity force.

The Range of gravity field

The universal gravitational law shows that the range of gravity force is infinity. So, earth’s gravity force does effect on all of things that are in universe. Suppose earth did formed x years ago. A star is at distance y light years of earth and y>x. The earth’s gravity field had not been reaching to star yet. Cause by considers relativity the speed of graviton is c. When star’s gravity force does reach to earth, earth to reaction of it sends a graviton toward the star. This graviton is pushing earth toward the star, as same star’s graviton is pushing star. 

Suppose an object leaves earth and it is moving toward the Mars. A graviton that is coming of moon and it is pushing moon, reaches to object. When this graviton arrives to object, another graviton leaves object and pushing object toward the moon. So, the range of gravity field has limitation, and it is not infinity.   

Does shift earth toward red and blue?

Redhift and blueshift is using for light. But this effect is common effect. Suppose a photon is moving upward the earth. A graviton leaves it and moving toward earth. When this graviton reaches to earth, another graviton leaves earth and moving toward photon. By consider the speed of graviton and photon, in during that earth’s graviton is passing distance between earth and photon, photon has a displacement equal d. (speed of graviton is greater than light’s speed). It is probability that graviton never reaches to photon and absorbs by other thing and arrives to it and another graviton leaves it and moving toward the earth. So, the photon’s graviton leaves it forever and addition to earth gravity field.   

When a photon shifts toward red in earth field, earth shifts toward blue. In interaction between earth and stars, earth shifts toward red. Please remember that there are many stars in universe that they are moving very fast and theirs speed are near the light’s speed.    

An observer on this star saw that earth shifts toward red.

With wishes

Hossein Javadi