Table of contents

One of the most fundamental laws in physics is that nothing can travel faster than the speed of light. However, two teams of researchers have now shown experimentally that electromagnetic pulses can be made to travel faster than c, the velocity of light in vacuum, and over relatively long distances.

Transistors are invariably made of semiconducting materials, but the special properties of superconducting materials make them attractive for some, highly demanding, applications Indeed, physicists have been trying to build superconducting devices with transistor-like properties – in particular devices that can amplify electrical currents – for more than 20 years. Now Giampiero Pepe of the University of Naples in Italy and colleagues led by Antonio Barone, together with Norman Booth of Oxford University in the UK, have built a superconducting device that exhibits large current amplification and other transistor-like properties (G P Pepe et al. 2000 Appl. Phys. Lett. at press). The device can also he operated to obtain negative current gain, which is not possible with semiconductor devices.

For small animals, sand scorpions are among the most dangerous creatures that live in the desert. But how are these creatures, whose eyes are rudimentary at best, able to spot their prey in the dark?

Optics is widely seen as a key technology for the 21st century. The exponential growth of Internet traffic, for instance, presents an enormous opportunity for the companies that build and sell the lasers, amplifiers, optical fibres that make up the world's communications infrastructure. Indeed, it is estimated that the market for fibre-optic components will be worth over $20bn in three years' time. Lasers and other optical technologies will also play a crucial role in healthcare, manufacturing, and the defence and aerospace industries.

Two challenges from fundamental physics are among seven "millennium prize problems" that were launched by the Clay Mathematical Institute at the end of May. The seven problems are among the biggest questions in mathematics today and have all remained unsolved despite the best attempts of researchers over the years. Researchers who are judged by the institute to have solved any of the problems will be awarded a prize of $1 million per problem. Solutions, however, must have been published in a "reputable refereed journal" before they will be considered for the prize.

When allegations surfaced last year that American state secrets had been reaching China by various routes, the US Congress decided to expand the government's control of technology. An amendment that was passed without debate transferred control of certain research activities that had been regulated by the Department of Commerce to the State Department. That amendment has had serious repercussions for academics who rely on satellites for their research.

Historians of science have long been intrigued by the role that the German physicist Werner Heisenberg played during the Second World War. They know that he worked on the German nuclear-bomb project, but have always wondered why Germany never managed to build an atomic weapon. Historians have also been baffled as to why Heisenberg visited his old mentor Niels Bohr in Nazi-occupied Copenhagen in 1941. Was Heisenberg fishing for information about American and British nuclear plans? Was he trying to prove his superiority over his former colleague? Or was he simply trying to tell Bohr that Germany's plans were unlikely to succeed? The meeting even inspired Michael Frayn to write the highly acclaimed play Copenhagen about what might have happened when the two physicists met (Physics World July l998pp35–36).

Two of Germany's leading physics laboratories, the Max Planck institutes for extraterrestrial physics and plasma physics in Garching, near Munich, have joined forces to set up a new centre for interdisciplinary plasma science (CIPS). Some 40 scientists will carry out research on complex plasmas, theoretical plasma physics and complex systems at the centre, which was officially opened in May. Plasmas are ionized gases and usually contain positive ions and negative electrons. Over 90% of the matter in the universe exists in the plasma state.

With the first draft of the human genome sequence complete, scientists are now turning their attention to the structure of the proteins themselves. Proteins are involved in all of the processes connected with life and death, and a knowledge of the precise structure and function of these molecules through "structural genomics", as the field is known, will be crucial if researchers are to develop new kinds of drugs.

The US Department of Energy is investing millions of dollars to transfer high-temperature superconducting technology developed at its national laboratories to the power industry. The department recently awarded $2.2m to IGC-Super Power LLC of Schenectady, New York, to develop manufacturing methods for "coated conductors" that could halve the electrical losses in underground transmission cables, transformers and other electrical equipment. Similar awards have been made to 3M of Minneapolis and MicroCoating Technologies of Atlanta. Superconductors are materials that lose their electrical resistance when cooled below a certain temperature (see Physics World March pp27–32).

Andrew Wallard's office is about to be demolished – but he does not seem to mind. In fact, the deputy director of the UK's National Physical Laboratory cannot wait for the bulldozers to tear down his office, along with the rest of the lab. By next summer Wallard and the 1200 other staff will have moved into a state-of-the-art building that is currently under construction at the lab's site in west London. It will be the first time in the 100-year history of the National Physical Laboratory (NPL) that all staff have been housed under a single roof.

Europe's bid to study the Earth's magnetosphere will rise from the ashes this month. The European Space Agency's (ESA) Cluster mission was originally launched four years ago, only to end in flames after the rocket carrying the spacecraft exploded (Physics World July 1996pp5–6). But having received strong backing from the scientific community the first pair of the four satellites that make up Cluster II are set to take off from Kazakhstan on July 12, to be followed by the second pair on August 9.

What has been the sole cause of the recent growth in the US economy? Ask Burton Richter and he will tell you that it is high-energy physics. He is referring to the fact that the Web was created by physicists at CERN, something that he believes politicians and the public need to know Richter, Who shared the 1976 Nobel prize with Sam Ting for their independent discovery of the charm quark, has been a robust defender of physics over the years. "If only we had the sense to patent the Web," he says, "we would not need governments to fund our science any more."

The name of Hendrik Brugt Gerhard Casimir is one in a long list of outstanding Dutch theoretical physicists that stretches from Hendrik Anthony Lorentz, remembered for the Lorentz transformation and the Lorentz force, through to Hendrik Anthony Kramers, remembered for his work on the Kramers-Kronig relations and the Wentzel-Kramers-Brillouin (WKB) approximation in quantum mechanics. Casimir will be remembered for predicting the so called Casimir effect – a universal attractive force that occurs between two conducting metal plates when they are about one hundred thousandth of a metre apart. The effect is due to vacuum fluctuations and has been verified experimentally

News in brief articles for July 2000

Philippe Busquin, the European Union's commissioner for research, has moved with remarkable speed since he was appointed last September. By January he had published a consultation paper on his big idea, the "European research area"– an initiative that was welcomed by science organizations across Europe– and by last month his plans had received a positive reaction from the European council of research ministers. Busquin's consultation paper* might have made less impact had it not started with some stark facts about research in Europe. The 15 EU states invest about 1.8% of their gross domestic product on R&D, compared with 2.8% in the US and 2.9% in Japan. Europe also employs proportionally fewer researchers than the US or Japan, and its trade deficit for high-tech products – currently Euro 20 billion per year– seems to be getting worse.

In his novel London Fields, Martin Amis writes: "Nothing, no information, can reach us faster than cosmic light. There's a speed limit up there. The universe is full of signs, circled in red, saying 186 287." Einstein had reached a similar conclusion in 1905. It was a surprise, therefore, to learn that physicists in Florence have observed pulses of microwaves travelling 25% faster than the speed of light (p3).

What is happening to the subject that we have loved and served? More than any other discipline, physics has transformed the face of civilization, particularly during the last century It has developed techniques and insights that have propelled chemistry biology and medicine to new heights. It has led to the genesis of modern engineering and has created vast industries, such as energy, communications, computing and the broadcast media. It has been the winner of wars and preserver of peace. It has played a seminal role in the emergence and development of the Internet, one of the most significant new communication media in history As we stand at the threshold of the 21st century its potential for economic and social innovation is greater than ever.

One year ago, on 18 July 1999, the Sunday Times of London carried an alarming article: "Big Bang machine could destroy Earth". The culprit was the Relativistic Heavy Ion Collider (RHIC), which was then nearing completion at the Brookhaven National Laboratory in the US. Particle collisions inside the accelerator, said the Sunday Times, might create black holes or new forms of matter called "strangelets", which would either blow up the planet or suck it into oblivion. A caption to the story asked: "The final experiment?"

Tony Weidberg's lateral thoughts article "In defence of anoraks" (April p64) provides much food for thought in the "why is physics not more popular?" debate. As a physics teacher at an independent school in the Channel Islands, I regularly discuss my pupils' progress with their parents. Most parents speak warmly of the subject and show a real interest in the work being taught. Where we have gone wrong in our teaching in recent years is that, if we talk to most youngsters, they either do not know what physics is or express complete indifference to the subject.

The proponents of the "philosophy is crap" sentiments mentioned by Nigel Sanitt in his letter (May p20) should be reminded that they are usually holders of the Doctor of Philosophy (PhD) degree! Indeed, my guess is that a large segment of the physics community considers the interface between physics and philosophy to be of great value, interest and social importance.

Your report about the recent conference at Cambridge on "rational perspectives on the paranormal" (May p5) discusses attempts by parapsychologists to reproduce paranormal phenomena under controlled laboratory conditions. You then say that "positive results are not unusual, but are rarely repeatable". Surely any repeatable experiments in this field would be regarded as a "holy grail" and pursued relentlessly? The results would no longer be rare by this time, and anybody at all – including sceptics – could reproduce them at will.

In her article on the benefits of scientific collaboration between the sexes, Gina Hamilton cited Caroline Herschel's work with her brothers, William and John, as an example of a successful partnership (April pp 17–18). However, the John mentioned by Hamilton was [Johann] Alexander Herschel, whose contributions to astronomy were insignificant compared with those of William and Caroline. It was only with great reluctance that he helped them in their efforts to build ever-more powerful telescopes. Indeed, it would appear that anyone who entered the Herschel household vas dragooned into assisting in some way. For the record, William and his wife Mary also had a son called John, who later became a celebrated astronomer in his own tight.

High-power lasers are widely used throughout industry to drill, cut and weld a range of materials with high precision. To address the need for increased industrial productivity, manufacturers continually demand lasers that can operate at greater speeds – which inturn calls for lasers that are evermore powerful.

A common goal in research into photon sources is to produce radiation that is brighter and more coherent than that from existing sources, or radiation that comes in shorter pulses or with shorter wavelengths. This applies equally to the smallest lasers and the largest synchrotron-radiation sources. Significant progress in two of these directions has been reported recently by groups based at the European Synchrotron Radiation Facility in Grenoble, France, and at the Advanced Light Source at the Lawrence Berkeley National Laboratory in the US.

Many current and future developments in the fields of communications, computing and imaging depend on the ability to detect individual photons with high efficiency. Single-photon detection has traditionally been achieved by two classes of device: photomultipliers and avalanche photodiodes. In both devices each photon produces an initial electron. However single electrons are extremely difficult to measure and the effect must therefore be amplified. Now researchers at Toshiba Research and the University of Cambridge in the UK have developed a new class of photon detector that does not rely on amplification.

Spectroscopy – the measurement of the properties of light emitted or absorbed by matter – is one of our most powerful tools to study nature. When a prism is used to separate the light from a flame in which salt has been sprinkled, distinct yellow lines become visible in addition to the usual colours of the rainbow. The wavelength of these yellow lines is directly related to the energy levels of the sodium atom, and in this way spectroscopy opens a window onto atomic structure.

To the casual observer, the Sun may appear calm and unchanging. However, the behaviour and energy output of our nearest star varies according to a cycle that lasts 11 years or so. This behaviour has been followed for centuries by counting the number of sunspots – dark regions that appear and disappear on the visible solar "surface". The rise and fall in the number of sunspots – and the accompanying variations in solar activity – have attracted renewed attention recently as the Sun approaches a peak in its 11year cycle. This interest has also been fuelled by spectacular images from spacecraft like the Solar and Heliospheric Observatory (SOHO).

IN THE era of the Internet, massive amounts of information and multimedia have become easily accessible in every corner of the world. The decreasing cost of storing data, and the increasing storage capacities of ever smaller devices. have been key enablers of this revolution. Current storage needs are being met because improvements in conventional technologies – such as magnetic hard-disk drives, optical disks and semiconductor memories – have been able to keep pace with the demand for greater and faster storage.

The year 1932 is widely seen as a turning point in the history of nuclear physics. Read any scholarly history or popular treatment of the subject, and you will almost certainly find reference to a spectacular triptych of discoveries made in that year. James Chadwick discovered the neutron – the first uncharged subatomic particle to be identified. Carl Anderson identified the position – the positively charged counterpart of the electron. And John Cockcroft and Ernest Walton used a particle accelerator to perform the first artificial disintegration of the atomic nucleus.

Strange and Charmed is an exciting examination of the roles and methods of scientists and artists, and the outcomes and consequences of their work. Through a collection of essays by artists, historians and scientists, the book examines – in substantial depth for such a slim volume – the interface and common areas between science and art. Some of the language used is, however, not what scientists are normally exposed to, and does require the reader to concentrate in places. And as its subtitle indicates, the emphasis of the book is very much on contemporary modern art.

Thomas Kuhn is famous for writing the surprise best-seller The Structure of Scientific Revolutions. Who would have thought that a book published in 1962 on the history of science would turn out to be what Steve Fuller claims is the best-known academic book of the second half of the 20th century? So well known is this book, indeed, that Physics World asked a sociologist (me) to write a review of a philosopher's analysis of the book because, as they told me, Kuhn is someone whom even physicists know about.

Managing Science is based on a graduate-level course taught by the authors at the US Particle Accelerator School, which has been held at several American universities at various times. The book covers a wide range of topics relating to managing and operating large facilities, particularly national and international high-energy physics labs such as Fermilab in the US, CERN in Europe and the High Energy Accelerator Research Organization (KEK) in Japan. The history and growth of some of these institutions are also discussed in depth.

Since the early 1900s, when Norwegian scientists first tried to apply mathematics to weather forecasting, physicists have played the central role in the science of meteorology Modern-day weather forecasting hinges on being able to describe the atmosphere in terms of physical and mathematical equations. However, this is no simple task – some would call the weather "nonlinear fluid dynamics at its most chaotic". All the same, as a physics undergraduate listening to my second year thermodynamics lectures, little did I suspect that one day I would be preparing and presenting the television weather forecast in my native Scotland.

He had done rather well in his PhD studies in theoretical physics and produced a highly praised thesis.