Faculty of Science

Detecting gravitational waves

David Blair

Gravitational waves created during the violent birth of the Universe, and through the formation and collisions of black holes, are thought to fill all of space, creating a background of vibrations that make everything in the universe jiggle, much like boats floating on a rippling sea.

Over 40 years physicists have developed more and more sensitive detectors, and today new detection technology is expected to be able to detect known sources - neutron stars that coalesce and merge to form black holes - within the next few years. Coalescing pairs of black holes and many other sources are also likely to be detected but because they are invisible in electromagnetic waves their population is uncertain.

The Australian International Gravitational Research Centre, within the School of Physics, is part of international efforts aiming to discover gravitational waves and harness the new spectrum for the purposes of gravitational astronomy. It has been a leading research centre for gravitational waves for more than 35 years. It has generated more than 500 research papers, many books and conference proceedings. 

The research centre includes a special remote facility, the Gingin Gravitational Wave Research Facility which was developed in an Australia-wide collaboration.  The facility contains huge clean room laboratories and an accommodation facility where researchers can stay for extended periods. The main equipment, an 80m scale high optical power laser interferometer facility is used for developing and testing new techniques for the next generation of large-scale gravitational wave detectors.  It is proposed that locally developed state-of-the-art  technologies  will be used for developing a large scale international observatory on the 50 square kilometre Gingin site provided by the WA Government

Current research

The AIGRC focuses across a broad range of research problems:

  • Advanced laser interferometer detector technology including vibration isolation and high optical power quantum optics.
  • High performance data analysis algorithms and supercomputer implementation for real time extraction of signals from noise, and their localisation in the sky.
  • Gamma ray bursts and other likely sources of gravitational waves.
  • Detection of electromagnetic counterparts of gravitational wave sources using the Zadko telescope and other fast robotic telescopes.
  • Application of spin-offs  from gravitational wave research including:
    • Development of airborne mineral exploration technology 
    • Development of advanced geothermal energy systems
    • Development of novel quantum measurement sensor instrumentation based on opto-acoustic interactions
  • Einstein first: Developing and testing school programs aimed at introducing physics from the modern Einsteinian paradigm from an early age.
  • Exploring the physics of three mode opto-acoustic parametric amplifiers developed from gravitational wave detection technology.
  • Theoretic studies on the applications of quantum measurement to the design of new gravitational wave detectors

Recent Discoveries and Outcomes

The group has published more than 140 research papers in the last five years, some of them as part of the LIGO Scientific Collaboration. A few examples are given below: 

  • First detailed prediction of parametric instability in advanced gravitational wave detectors.(Physical Review Letters)
  • Introduction of the three mode opto-acoustic parametric amplifier (Physical Review Letters)
  • Upper limits on gravitational waves from the big bang (Nature)
  • Use of Squeezed light to increase the sensitivity of LIGO (Nature Photonics)
  • First observation of three mode parametric instability in a free space optical cavity (submitted to Physical Review letters)

Affiliations and partnerships

The AIGRC enjoys strong collaborative links with top research institutions throughout Australia and around the world:

  • Australian Consortium for Gravitational Astronomy (ACIGA), which coordinates research across 6 Australian universities and CSIRO. 
  • LIGO Scientific Collaboration, which is developing and operating two large scale detectors in the USA. It collaborates with other detector collaborations in Europe (Virgo, operated by the European Gravitational Observatory) in Japan (KAGRA) and in Germany (the British-German GEO detector). It has strong collaborative links with top universities in China, including University of Science and Technology of China, Beijing Normal University, Huazong University of Science and technology and Tsinghua University.

 

Key researchers/personnel

Key sites