Third generation gravitational wave detectors. The challenge of Einstein telescope in Europe

In 2010 the concept design of ET was released. Gravitational waves had not been observed yet and most of the e orts were leading to achieve higher sensitivity exploiting the infrastructures developed for LIGO and Virgo. Today we are re-examining more operatively the possibility to study an actual proposal of Einstein Telescope, in the context of 3rd generation (3G) detector network. The discovery of gravitational waves, the observation era using a detector network and the birth of multi-messenger astronomy is the basis on which such an engagement relies. At the end of the process Einstein Telescope project will be compliant with the worldwide scenario as it appears today in order to keep the European scienti c role in this context.