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If gravity waves are eventually to be detected, then this surely is giving it the best chance ever: five physicists, all graduating this year with their PhDs, after devoting about 20 years in total to the goal.

They were all co-supervised by David Blair and it is a record for the School of Physics , and probably for the University.

Winthrop Professor Blair describes how their research projects complemented each other in the quest for the elusive gravity waves: "Jean-Charles Dumas has worked for five years to help create ‘the quietest place in the universe'.

"This place is inside vibration isolators where freely-suspended mirrors move extremely slowly. The vibration forces acting on the mirrors are less than if they were floating in interplanetary space.

"Pablo Barriga helped to control the vibration isolates and worked out how to build special optical cavities that purify laser light by freeing it of all the fluctuations that could make gravitational wave detectors give false readings.

"Slawek Gras worked out how to reduce instabilities in gravitational wave detectors which otherwise could make them whistle uncontrollably.

"Eric Howell found a new method of estimating how many gravity wave signals there would be and how they were distributed in space.

"Finally Andrew Sunderland helped to develop an instrument called a magnetic gradiometer which can detect minerals far underground - making gravity waves useful!"

Einstein predicted gravity waves, generated by the formation of black holes in the universe. While physicists agree the theory is sound, nobody has detected them yet.

Professor Blair and his team are among the world leaders in the race to detect the waves, despite other countries spending hundreds of millions of dollars more on their research.

"I don't know what difference the discovery of gravity waves will make to humanity," he said. "But Heinrich Hertz, who discovered electromagnetic waves, could not have imagined the mobile phone and all the other devices of our current electronic revolution either!"

The five physicists came to UWA to do their PhDs with Professor Blair from five different universities: Dr Dumas did his undergraduate studies at UWA, while Dr Barriga came from Universidad de Chile; Dr Sunderland from the University of New South Wales; Dr Howell from Cardiff; and Dr Gras from Poland.

While they are quite different personalities, they became firm friends during their research and enjoy playing soccer together.

Dr Dumas said that one of the problems that limited gravitational wave detectors (interferometers) was the noise of the earth's seismic activity as well as human generated activities, so he set about creating his advanced compact vibration isolator prototype, two of which are now being used at the observatory in Gingin.

Dr Barriga addressed the key technologies required to improve the sensitivity of the next generation of interferometric detectors. His work included a study of thermal effect due to high circulating power, and a separate study of a vibration isolation system.

Dr Gras said that advanced detectors required an extremely high optical power to improve the coupling between the gravitationial wave signal and the optical field.

"My thesis can be considered as a pathway towards providing a tool for the analysis of the parametric instabilities in the next generation interferometers," he said.

Dr Howell summarised his work as investigating the gravitational wave signals from populations of highly energetic and violent explosions throughout the Universe.

And Dr Sunderland's thesis described a magnetic gradiometer that could be used for geophysical exploration. "The project was a spin-off of UWA's gravitational wave group that utilised our existing technology and detection techniques," he said.

• From UWA News, 22 March 2010