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Principle of Equivalence.
( Last checked 2017/01/15 - The estate of Paul Marmet )
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Series #6 ---Comparing Inertial and Gravitational Accelerations.
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Question - (6-A)
Einstein's theory of Relativity considers that the gravitational force of acceleration is identical to the inertial force of acceleration. Einstein claims that these two accelerations are undistinguishable. In reality, is there any possibility to distinguish these two accelerations?
A - Certainly. Consider a mass standing on the surface of the Earth. After one year, the mass submitted to gravitational acceleration is always standing there, without changing its energy or velocity. Another identical mass is submitted to an inertial acceleration of one G in outer space by a rocket. After one year, the energy given to the mass is such that its velocity has reached an important fraction of the velocity of light. An enormous amount of energy has to be given up to the accelerated mass in order to produce such a continuous acceleration. When that last mass falls on Earth its energy would produce a gigantic crater on the impact.
Einstein's theory claims that these two phenomena are equivalent and undistinguishable. This is non-sense. The difference can certainly be seen very easily. In order to convince people, Einstein adds that there is no difference for the observer located in the moving frame of reference.
To illustrate Einstein's argument, let us consider another case when we observe relative motion. A well-known example is the observation of the Sun and the stars crossing the sky everyday, (or the sunrise or the sunset). Relative to the Earth surface, the sky is moving around us and the Sun disappears below the horizon. However, we all know that Galileo, using astronomical data, observed that in fact, it is the Earth that rotates and not the Sun. Using astronomical information external to the Earth surface, Galileo found the correct motion of the Earth, which led him to a correct understanding of the motion of the planets in the solar system. The simple observation of the relative motion of the Sun and stars around us, which led to the pre-Galilean naive claim of the motion of the sky around us, was very poor science. GOOD SCIENCE TAKES INTO ACCOUNT ALL POSSIBLE OBSERVATIONS AVAILABLE. It is very bad science to ignore (or hide) voluntarily some of the information available.
Let us go back to the initial problem of acceleration. The inertial acceleration given to a mass requires energy to be able to accelerate. In the case of gravitational energy, there is a force without displacement, therefore no energy is required.
In the case mentioned above about the inertial acceleration of the mass during one year, it is bad science to ignore the fact that the mass submitted to an inertial acceleration acquires energy, while a well informed (non blind) observer can measure that the velocity increases as a function of time. The mass accelerated by the rocket has acquired energy and an increase of "relativistic" mass that cannot be ignored.
One must conclude that the Einstein's principle of equivalence between inertial and gravitational acceleration leads to a physical incoherence between inertial systems. This equivalence is not compatible with coherent observations. The principle of equivalence between inertial and gravitational mass which ignores that the energy has been given up to the mass is bad science, belonging to pre-Galilean science. Inertial and gravitational accelerations are certainly distinguishable, just as we know that the Sun does not really set. It is the Earth that rotates.

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