Nominations for the positions of President, Secretary, Treasurer, and members of the committee should be forwarded to the secretary, Tony Lun, lun@vaxc.cc.monash.edu.au prior to the meeting, by 12:00 Tuesday, 7 July. (According to the rules, no person may be elected to the same office for more than two consecutive terms - however, we have only been "official" for one term til now.)
Agenda: 1. Minutes of 1st BGM, Adelaide, 13 February, 1996. 2. President's report. 3. Treasurer's and auditor's reports. 4. Appointment of auditor for next session. 5. Election of officers. 6. Date and venue for ACGRG3. 7. Other business: (i) Matters arising. FURTHER ITEMS SHOULD BE FORWARDED TO THE SECRETARY: lun@vaxc.cc.monash.edu.au
July 6-11 1998 University Of Sydney, Australia The final circular will be distributed to those who have registered. HOME PAGE: http://www.maths.usyd.edu.au:8000/u/ACGRG2/ The draft programme is included here for the benefit of potential late registrants who have not yet made up their mind:CLICK HERE FOR LATEST PROGRAMME
MEMBERS' NEWS
Dr Susan Scott has been recently appointed to the position of Lecturer (Continuing) in the Department of Physics and Theoretical Physics, ANU.
MEDIA EXCERPTS
FROM Panorama Dec 1997, pp. 114-119 (Ansett inflight magazine)SOUND REASONING
________________________________________________ The human race is on the threshold of something dramatically new that may rival the greatest scientific discoveries of all time - something that may totally alter our view of the universe. David Blair looks at new research which will allow us to hear the scream of dying stars. ________________________________________________ Most of what we know about the world at large we know through sight and sound. Our exquisitely sensitive ears allow us to hear vibrations almost as small as an atom, while our eyes can detect much less than a millionth of a billionth of a Watt of light power from a faint star on a moonless night. Modern technology has dramatically extended our sense of vision. Now, night-vision glasses allow us to see infra-red light that we otherwise only feel as the warm glow from a fire. X-rays are simply a higher-energy form of light which we can't feel at all, but which allow us to see our insides as well as the contents of our bags at security counters. Radio is a low-energy form of light. Although we use it to encode sounds and send voices around the world, radio has nothing to do with sound at all. We can equally well send sounds by encoding them in light pulses, as happens with most of our long-distance telephone conversations. Using radio, we have also enormously extended our vision -- radio telescopes are now able to see objects in fine detail far across the universe. Almost all of what we know about our vast universe we know from our extended sense of vision. Telescopes using every conceivable part of the light spectrum peer out at the universe, giving humanity an almost unbelievable wealth of views across both space and time. Some of the light we see has been travelling towards us for almost the age of the universe itself. What we see in this light is an image of the universe when it was much less than a million years old, long before stars and galaxies had formed and 10 billion years before the birth of our own solar system. Have you ever looked at a beautiful landscape painting or photograph and imagined the sounds of the sea and the wind and the birds? Or an 18th-century battle scene where the clash of armour and the booms of the cannons are silent? Because we can hear, we are able to imagine and fill in the silences. But what if we were a deaf species? Could we guess at the sounds of the forest or imagine the sounds of battle? Well, we are a deaf species! True, we can hear sounds made on the surface of our planet. But we are deaf to the universe. "Well, of course," you say. "Sounds go through air, but they can't go through the vacuum of space." Right? No, wrong! BIONIC EARS Sounds are vibrations-pressure waves of vibrating atoms that make our eardrums vibrate -- and Albert Einstein proved 80 years ago that vibrations can indeed travel through space. They are called gravity waves, carry prodigious amounts of energy, travel at the speed of light and are almost unstoppable. And, soon, humanity will have the bionic ears it needs to listen to them. So what will the universe sound like? That question is a bit like asking a deaf person to describe the sounds of a forest. Almost an unfair question, but this, of course, is where science excels. After decades of effort, physicists can now make some pretty good guesses and, surprisingly, we expect the universe to sound a bit like a forest. Black holes will make short, sharp clicks like those of a woodpecker. Pairs of neutron stars will make chirrups like bird calls. The deaths of the first generation of stars in the universe 12 billion years ago will combine to make a sound like the wind in the treetops. Spinning neutron stars will make pure whistles. The harnessing of gravity waves for astronomy is being pioneered by a rapidly growing army of physicists around the world. The first detectors in the world were huge, supercooled metal bars equipped with the most sensitive microphones ever made. Four of these are now in continuous operation: two in Italy, one in Perth and one in Louisiana. The Perth and Italian detectors have seen tantalising signs of possible signals but need even more sensitivity to be able to say, "We have detected gravity waves." Every major industrialised country is building new and improved detectors. In the United States, half a billion dollars is being spent building two enormous gravity-wave detectors, one in Washington State, the other in Louisiana. The detectors are among the biggest machines ever made, with eight kilometres of vacuum tunnels through which powerful laser beams are used to detect vibrations a billion times smaller than the softest sound. Big new projects in Italy, France, japan, Germany, Britain and the Netherlands are underway, and physicists are in enormous demand to take part in this exciting challenge. In Australia, a consortium of physicists from Perth, Adelaide, Canberra, Melbourne and Sydney have been planning a modestly sized but very powerful new gravity-wave detector for a site at Gingin near Perth, with support from the West Australian government. The new detector will be able to match the much more expensive projects in the US and Europe because of a breakthrough in the use of artificial sapphire for high-power laser optics. So far, Australia is one of the world leaders in this field but many fear that, yet again, this country will fail to capitalise on its innovation and leadership. The Nobel Prize for the proof of the existence of gravity waves was only awarded in 1993. Still, they have not been directly detected, but physicists know they are onto something good -- just as in 1886, when Heinrich Hertz proved the existence of electromagnetic waves. He never guessed that radio and TV and mobile phones would have revolutionised the world 100 years later. We have no idea what will come out of this totally new spectrum, apart from lots of wonderful technological innovations like the sapphire clock -- the most stable clock in the world -- which came out of gravity-wave developments in Perth-and which now supports a new Australian high-tech export industry.David Blair is a physicist at the University of Western Australia. His new book, Ripples in a Cosmic Sea, co-authored by Geoff McNamara, tells the whole story. It was published by Allen and Unwin in October 1997.
OCKHAM'S RAZOR - Radio National listeners should note that the importance of gravitational wave detection will get a tiny mention in a broader piece in which your trusty editor defends physics against the enemies of science; to be broadcast sometime in the next couple of months.