Throughout the ages, we have only been able to see the universe but could not hear it. This is a pity since more than 99 percent of the universe lie in the dark and may never be observable with light or any electromagnetic waves. Since September 14, 2015, everything has changed: the first direct observation of gravitational waves emitted by two colliding and merging black holes opens up a new era of gravitational wave astronomy. We have established a new sensory organ and will be able to hear the universe from now on.
The 16th EInstein Lecture Dahlem was given on October 25, 2016, by Professor Karsten Danzmann, Director at Max Planck Institute for Gravitational Physics (Albert Einstein Institute) and of the Institut für Gravitationsphysik at Leibniz Universität Hannover.