Looking back at the Big Bang
The provision of direct proof of Einstein’s gravitational waves is one of the most important challenges that remain to be fulfilled by modern science. In addition to underpinning the general theory of relativity – particularly for extreme gravitational fields in the vicinity of black holes – scientists hope that the direct observation of gravitational waves will also herald the era of gravitational wave astronomy, and thus provide new insights into the universe: it would open a window on the very early days of the universe for the first time.
As, up to now, cosmological observations of the sky were limited to the electromagnetic spectrum, the information we obtain about the emergence of the universe only concerns the period from around 380,000 years after the Big Bang. Earlier developmental phases have evaded observation, as light and matter constantly interacted with each other back then and the universe only became transparent to electromagnetic radiation after this period. The various theories that exist on the early universe are, therefore, experimental and have not been empirically verified. The direct measurement of gravitational waves would enable us to look back to the first billionth of the first second after the Big Bang and thereby obtain completely new insights into the universe.
Because comprehensive information can only be obtained from a large number of sources using measurement equipment that operates simultaneously in places located at considerable distances from each other, gravitational wave research is an international undertaking. Therefore, scientists throughout the world have been cooperating closely on this research for some time. They share technological research and insights, theoretical advances and data analysis methods and tools.
The German-British observatory is located near Hanover and is operated by researchers from the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI), the Leibniz Universität Hannover and the British universities of Glasgow, Cardiff and Birmingham. The GEO project is funded by the Max Planck Society, the German federal state of Lower Saxony, the Volkswagen Foundation and the British Science and Technologies Facilities Council (STFC). GEO works closely with the QUEST Cluster of Excellence (Centre for Quantum Engineering and Space-Time Research) in Hanover.
(For further information, visit: http://www.geo600.de)
The French-Italian-Dutch observatory, which has three-kilometre-long laser arms, is located in Cascina near Pisa. This project has set itself the objective from the outset of carrying out measurements at particularly low frequencies. Virgo is financed by the French CNRS (Centre national de la recherche scientifique) and Italian INFN (National Institute of Nuclear Physics)
The LIGO gravitational wave detectors comprise one two-kilometre-long and one four-kilometre-long instrument located in Hanford in the US state of Washington, and a four-kilometre-long instrument in Livingston, Louisiana. The LIGO project, which was developed and is operated by the California Institute of Technology (CalTech) and Massachusetts Institute of Technology (MIT), is financed by the National Science Foundation (NSF).
(For further information, visit: http://www.ligo.caltech.edu/)