The expanding Earth: a sound idea for the new millennium

18 1 A short review of the more relevant modern arguments in favour of the conception of the Earth in expansion is provided. The advantage of the expanding planet idea is a common explanation of several outstanding problems coming from palaeontology, palaeomagnetism, geology and climatology. All these problems should be regarded as be a sort of distortion effects, which arise if we try to reconstruct the situation of old geologic times adopting the modern Earth’s radius – the distortions become larger and larger as we came back in time. As a consequence the expanding Earth could be considered a natural generalization of the plate tectonic. A strong support to this generalization came from the simple and united explanation that can be found in the expanding Earth of the classical geodynamic phenomena of the polar motion and the true polar wander by an inversion of the paleogeographic position of the triple points. The conviction is expressed that basic information about this old global tectonic conception should be provided in secondary school and university courses.