Detecting Gravitational Waves
BMBF Joint Project – Detecting Gravitational Waves
Astrophysical events like the merging of two black holes produce vibrations in spacetime, referred to as gravitational waves. These phenomena can be detected using special-purpose facilities: gravitational wave observatories. Though Albert Einstein postulated the existence of gravitational waves roughly a century ago, the first experimental proof wasn’t delivered until 2015. Today, researchers are already working on the third generation of observatories. That generation includes the planned Einstein Telescope, which is intended to more precisely measure the reverberations of the Big Bang and provide detailed insights into merging processes in space. To do so, the telescope will cover a frequency range from less than ten hertz to over 500 hertz, a point at which today’s gravitational wave observatories reach their limits.
In this regard, Universität Hamburg’s Institute of Geophysics is working to improve the telescope’s sensitivity in the low-frequency range. To do so, a method is being developed to predict the gravitational coupling of seismic waves at the position of the mirror, so that this effect can be retroactively compensated for. An effect known as gravitational gradient or Newtonian noise, in which the attracting forces affecting the pendulum are influenced by movements in the surrounding area, can be predicted using a network of seismometers. The challenge lies in filtering the countless signals to find the actual source of noise. To help researchers accomplish this task, new machine learning methods are being developed and applied.
Germany’s Federal Ministry of Education and Research (BMBF) is supporting the joint project, led by the RWTH Aachen, with ca. three million euros of funding, spread over three years. More than half a million euros will go to three subprojects at Universität Hamburg, including one at the Institute of Geophysics.