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'''Gravitation''' is the tendency for every object with [[mass]] to attract every other object with [[mass]]. Gravitation is what gives everyday objects [[Weight|weight]], and what causes objects that are dropped from a height to fall to the ground. Gravitation also keeps the [[Moon|moon]] in orbit around the [[Earth]] and the Earth in orbit around the [[Sun|sun]].

'''Gravitation''' is a [[scientific theory]] which attempts to define the tendency for every object with [[mass]] to attract every other object with [[mass]]. Gravitation is what gives everyday objects [[Weight|weight]], and what causes objects that are dropped from a height to fall to the ground. Gravitation also keeps the [[Moon|moon]] in orbit around the [[Earth]] and the Earth in orbit around the [[Sun|sun]].

The attraction depends on the mass of the objects and the distance between them.  The gravitational force between two persons is minuscule; however, the gravitational force between a person and the [[earth]] is quite significant.  However, if the person gets in a spacecraft and flies halfway to the moon, the gravitational force between him and the earth will significantly decrease because they are farther apart.  The force will never become zero no matter how far he goes from the earth; however, if he goes far enough away, it will be counterbalanced by other masses' gravitational force.

The attraction depends on the mass of the objects and the distance between them.  The gravitational force between two persons is minuscule; however, the gravitational force between a person and the [[earth]] is quite significant.  However, if the person gets in a spacecraft and flies halfway to the moon, the gravitational force between him and the earth will significantly decrease because they are farther apart.  The force will never become zero no matter how far he goes from the earth; however, if he goes far enough away, it will be counterbalanced by other masses' gravitational force.

== Scientific Theories of Gravitation ==

== Scientific Theories of Gravitation ==

Over the past four centuries, many scientific [[Theory|theories]] of gravitation have been proposed. Three of these theories have gained sufficient widespread acceptance to be considered, for a time, "correct" theories.

Over the past four centuries, many [[scientific theory|scientific theories]] of gravitation have been proposed. Three of these theories have gained sufficient widespread acceptance to be considered, for a time, "correct" theories.

=== Galilean Gravitation ===

=== Galilean Gravitation ===

It has been discovered in 1985, with high school calculus, by a sculptor turned electrical engineer (since sculptors have to eat and sculpting alone is not a suitable profession for this especially in Boston, MA that has ''"The Boston Museum School"'', the best in the country, but only one visual artist making living with his trade alone; and he is a painter).  

It has been discovered in 1985, with high school calculus, by a sculptor turned electrical engineer (since sculptors have to eat and sculpting alone is not a suitable profession for this especially in Boston, MA that has ''"The Boston Museum School"'', the best in the country, but only one visual artist making living with his trade alone; and he is a painter).  

The discovery was done accorfing to Einstein's prescription for making discoveries: ''"When all the eperts decide that something can't be calculated, there comes an ignorant who doesn't know it, and calculates it."''  

The discovery was done according to Einstein's prescription for making discoveries: ''"When all the experts decide that something can't be calculated, there comes an ignorant who doesn't know it, and calculates it."''  

It turned out that [[Hubble constant]] should be calculated before jumping to conclusion that it can't be done and that the universe is expanding. It turned out that it can be calculated and it produces the observed value of [[Hubble constant]]. So it implies that we live in eternal, stationary universe, which only looks like expanding for the reason of coupling between [[time dilation]] and [[curvature of space]].  

It turned out that [[Hubble constant]] should be calculated before jumping to conclusion that it can't be done and that the universe is expanding. It turned out that it can be calculated and it produces the observed value of [[Hubble constant]]. So it implies that we live in eternal, stationary universe, which only looks like expanding for the reason of coupling between [[time dilation]] and [[curvature of space]].  

The ''"[[gravitation demystified]]"'' is Einsteinian type theory (see article ''"[[gravitation demystified]]"'' for details). It explains gravitational force in terms of quantum effect of particles taking spontaneously (without being prompted to do so by any direct force) the most probable position of lowest energy in spacetime. It happens in the intrinsically flat, [[Minkowski]], spacetime (as also proposed in 1993 by Narlikar and Arp <ref>Narlikar, J. & Arp, H. ''"Flat spacetime cosmology - a unifiedframework for extragalactic redshifts"''. 1993, Astrophysical Journal, Part 1  

The ''"[[gravitation demystified]]"'' is Einsteinian type theory (see article ''"[[gravitation demystified]]"'' for details). It explains gravitational force in terms of quantum effect of particles taking spontaneously (without being prompted to do so by any direct force) the most probable position of lowest energy in spacetime. It happens in the intrinsically flat, [[Minkowski]], spacetime (as also proposed in 1993 by Narlikar and Arp <ref>Narlikar, J. & Arp, H. ''"Flat spacetime cosmology - a unified framework for extragalactic redshifts"''. 1993, Astrophysical Journal, Part 1</ref> ) that is necessary for strict conservation of energy, used to demonstrate that our universe is not expanding. The conservation of energy follows from Noether theorem, in absence of expansion of universe. The "[[gravitation demystified|demystified gravitation]]" is meant as a continuation of Einstein's general relativity based on his 1917 stationary model of universe with an important change of introducing non symmetric temporal part of Ricci tensor (named "Hubble tensor") which also removed Einstein's cosmological constant (''"the biggest blunder of my life"'' in Einstein's words) from his field equation. Coupling the curvature of space to the time dilation made the time running at the deep space galaxies exponentially slower with distance, which produced the observed illusion of accelerating expansion.

The [[cosmological redshift]] was taken not long time ago for a sign that the universe is expanding. The project meant to prove that expansion of space is decelerating, to add credibility to the Big Bang hypothesis (in agreement with John Archibald Wheeler's theory), showed that to the contrary, the universe seems to be expanding with accelerating expansion  

 

The [[cosmological redshift]] was taken not long time ago for a sign that the universe is expanding. The project meant to prove that expansion of space is decelerating, to add credibility to the Big Bang hypohtesis (in agreement with John Archibald Wheeler's theory), showed that to the contrary, the universe seems to be expanding with accelerating expansion  

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