Fundamental laws of nature confirmed by free fall

The principle of conservation of energy is often demonstrated by means of free fall. In mechanics, states of a body with potential and kinetic energy are energetically compared. Based on the mass concept of relativistic mechanics, energy conservation is considered to be linked with mass conservation. We show that the process of free fall can be interpreted more thoroughly, if the cause-effect principle and the mass concept of thermodynamics are applied. For the first time in the history of physics, the mechanism of energy conversion in free fall can be shown, which is valid for any object, whether body or elementary particle. The phenomenon of falling confirms the following facts to be valid of on a fundamental level: i) The principle of conservation of energy, ii) The equivalence of inertial and gravitational mass, iii) The real mass increase of any object with its velocity, and iv) The continuousness of space and time. At the end of the article we explain why the theory of general relativity is unsuitable to demonstrate the conservation of energy during free fall.