How are gravitational waves recorded

UHH newsletter

Research into gravitational waves is a major project of the US National Science Foundation, California Institute of Technology (Caltech) and Massachusetts Institute of Technology (MIT). A total of around 1,000 international researchers are involved.

Detectors four kilometers long

The detectors in Hanford (Washington state) and Livingston (Louisiana US state) each have two vacuum tubes that are four kilometers long. Your interior is continuously measured with the help of a laser beam. When a gravitational wave runs through the arms, different compressions or elongations occur, which are detected by the laser.

Gravitational waves enable a new view of the universe

According to the general theory of relativity, gravity or gravitation is not a force (as it was with Newton, for example), but a property of space and time. Gravitational waves are created when masses are accelerated - for example when a supernova explodes. They are distortions in the structure of space-time and propagate at the speed of light. So far there has only been indirect evidence of their existence. Their direct observation enables a new view of the universe, because previously the knowledge about the universe was based on measurements of electromagnetic waves such as light or gamma radiation.

With the help of gravitational waves, previously hidden phenomena could be made visible - e.g. so-called black holes, in which such strong gravity acts that not even rays of light can escape.

Even more precise measurements thanks to quantum technology from the University of Hamburg

The University of Hamburg and the working group of Prof. Roman Schnabel have been a member of the team of the German-British gravitational wave detector GEO600 and of the LIGO Scientific Collaboration (LSC) since spring 2015.

Before moving to Hamburg, the physicist has been researching quantum technologies for future gravitational wave detectors at Leibniz Universität Hannover since 2002. There he also developed the world's first source of light with a so-called “squeezed quantum noise”, which enables a gravitational wave detector to make more precise measurements. This source has been in use in the GEO600 detector since 2010.

Prof. Schnabel has been chairman of the LSC “Quantum Noise” working group since 2013. At the University of Hamburg he and his working group will research how the measurement sensitivity of gravitational wave detectors can be further improved. The two LIGO detectors that have now observed the gravitational wave are not yet equipped with squeezed light.

To the official press release of the LIGO Scientific Collaboration (LSC) (PDF)