Revisiting the energy in gravitational waves

Abstract

Five years ago, at the Third Joint Italian–Pakistani Workshop on Relativistic Astrophysics, I put forward an argument why gravitational waves would be much more difficult to detect than was supposed. In view of the observation of gravitational waves in 2015, and an earlier claim that they were missing, it is worth looking again at the arguments. Here, I review the basic physical argument and then re-consider the earlier prediction. Following Weber and Wheeler, who had demonstrated the reality of gravitational waves by obtaining the momentum of test particles along their path, there had been more work done in this direction. It is also worthwhile to compare the results from that work with the proposal for the energy in the waves and that will also be mentioned.