Jorma Rantakivi : Gravitation III – Velocity-dependent force

General relativity gives the orbit of a celestial body as a solution to Euler's equations. The solution is a time-dependent position vector that minimizes the orbital length in curved space. The same Euler equations can also be viewed from another perspective. They can be interpreted as a group of equations for components parallel to the coordinate axes of the acceleration of the body as a function of the velocity and position of the body in a rectilinear Euclidean space. Accelerations can be solved numerically from the group of equations. Since the acceleration is the same as the force per unit mass, the result is the relativistic force acting on the object. In this way, the orbits of several bodies can be calculated simultaneously according to general relativity. The book presents a more detailed calculation algorithm, a program in the FORTRAN language and several calculated example cases.

The author has completed a university degree with a major in physics and a minor in mathematics. The author has done his life's work in the supervision of nuclear power plants at the Radiation and Nuclear Safety Authority. In addition to the technical work, the author has developed numerical models for thermodynamics, heat transfer, neutron flux calculation and liquid and gas flow calculations. The author has been interested in gravitation and the theory of relativity since his school years. About 10 years ago, the author began to study gravitational theories more intensively and also began to perform calculations based on Newton's and Einstein's theories. The results of the calculations have been reported in books 'Gravitation' and 'Gravitation II' written under the pseudonym U. Kivi and in book 'Gravitation III' written under his own name. In addition, the author has written the book 'Thermodynamics' under the pseudonym U. Kivi.