An alternative way to locally measure the Hubble constant using Gravitational Waves and PTA

Jorge Alfaro, Mauricio Gamonal

Published 2019-02-12Version 1

Recent research show that the cosmological components of the Universe should influence on the propagation and observation of Gravitational Waves. Furthermore, it has been proposed a new way to measure the cosmological constant using Pulsar Timing Arrays (PTA). However, these results have considered very particular cases (e.g. a Universe filled only by dark energy or by a mixing with dust). In this work we propose an extension of this model: We considered a Universe filled by different perfect fluids, with arbitrary equations of state, and studied the propagation of Gravitational Waves within the context of the LCDM model. From this framework we obtained a relationship, e.g. an analytical formula that differs by 1.5 \% from numerical simulations, between the value of the Hubble constant and the observables of PTA experiments, which are expected to measure time residual from local pulsars due to the pass of Gravitational Waves by the IPTA project in the near future.