The large-number hypothesis and the Earth's expansion-II

Careful study by Owen of the displacements of the continents renders it likely that the Earth radius increased by almost 20% during the past 200 million years. Ramseys proposal that the Earth liquid core is a high-pressure phase of the mantle material is adopted to calculate the Earth radius under variableG. It is shown that ifG varies according to the large-numbers hypothesis of Dirac, the primordial Earth would have had radius 700 km less than the modern value. If it is assumed that the Earth began to respond and, hence, expand only 2 × 10⁸ yr B.P., the expansion as large as 700 km is shown to be energetically plausible.