Table of contents

Superfluid helium-3 has fascinated researchers since it was discovered in 1972. At temperatures below a few millikelvin. this bizarre liquid loses its viscosity allowing it to leak through tiny pores in seemingly watertight vessels. Theorists had previously thought that the phenomenon occurs when the helium-3 atoms – which are fermions with half-integer spins – pair up to form bosons, particles with zero or integer values of spin. Now Yuriy Bunko and co-workers at the Centre de Recherches sur les Très Basses Températures in Grenoble, France, have discovered a new type of superfluid behaviour in which four atoms couple together, rather than two (Y Bunkov et al. 2000 Phys. Rev. Lett. 85 3456).

Magnetic recording is a crucial component of today's information-technology industry But the speed with which data can be "written" to computer hard disks is currently limited to the nanosecond level. Now a team of physicists in Switzerland has imaged the motion of the magnetic moment in a thin cobalt film with picosecond resolution. The technique could lead to much shorter read/write speeds for data (Science 2000 290 492).

An international team of astronomers has detected the most distant gamma-ray burst in the universe so far. Observations made at the La Silla and Paranal observatories in Chile have revealed that the powerful explosion occurred when the universe was less than l500 million years old, or only 10% of its present age. The remote galaxy in which the burst is thought to have taken place is so faint that astronomers are unable to detect it directly Such bright bursts could therefore reveal hitherto undiscovered galaxies. The results were presented at an international conference on gamma-ray bursts held in Rome last month (www.ias.rm.cnr.it/rome2000/).

Physicists reacted with delight last month at the news that the 2000 Nobel Prize for Physics had been awarded to three pioneers of the IT and communications revolution. "The work of Zhores Alferov, Herbert Kroemer and Jack Kilby is highly deserving of a physics Nobel prize, which is meant to be for inventions and discoveries that have benefited mankind," says Federico Capasso, vice-president for physical research at Bell Laboratories in the US. "Integrated circuits, semiconductor lasers and high-speed heterojunction transistors have definitely [benefited mankind], since they have enabled the computer and telecommunications revolution, which in turn is driving major advances in basic science."

A physicist who helped to discover conducting polymers has shared this year's Nobel Prize for Chemistry. Alan Heeger from the University of California at Santa Barbara was awarded one third of the prize "for the discovery and development of conductive polymers". The other winners were Alan MacDiarmid of the University of Pennsylvania in the US and Hideki Shirakawa of the University of Tsukuba in Japan. Conducting polymers are used as anti-static materials, filters for computer screens and electronic windows.

A physics-based technique that will help doctors in the fight against cancer has been approved by the Food & Drug Administration, the body that oversees all medical treatments in the US. The computer-based system, called Peregrine after the patron saint of cancer patients, allows doctors to target radiation at tumours more accurately than in the past. It will allow medical teams to tailor radiation treatments to individual patients, increasing the dose of radiation aimed at tumours while minimizing damage to healthy tissue.

Indian physicists are celebrating the production of the country's first radioactive-ion beam. They are dubbing it a modest landmark that marks India's entry into a growing area of nuclear research that has applications in fields such as astrophysics and medicine. The beam of the radioactive isotope heryllium-7 was produced at the Nuclear Science Centre (NSC) in New Delhi.

Later this month politicians will meet in the Hague to try and press ahead with the reductions in greenhouse-gas emissions agreed at Kyoto in Japan three years ago. The treaty signed at Kyoto aims to reduce emissions of gases such as carbon dioxide, nitrous oxide and methane in order to halt the rise in the Earth's temperature, which is estimated to have increased by about 0.6 °C since the late 19th century and could rise by more than 1 °C by 2010. But have climate researchers got their facts right? Could nature in fact have a major hand in heating the Earth?

Most cosmologists agree that less than a tenth of the universe is made up of normal or baryonic matter – mainly neutrons and protons. They believe that the remaining 90% consists of "dark matter" and, possibly, a mysterious substance known as "dark energy" or quintessence (see pp31–37). However, in the absence of any direct evidence for dark matter – such as the detection of a dark-matter particle – a small band of astrophysicists is arguing that this non-baryonic matter does not exist and that the laws of gravity need to be modified instead. Now Stacy McGaugh of the University of Maryland in the US is claiming that this so-called "modified Newtonian dynamics" has predicted features that are observed in the cosmic microwave background – the radiation left over from the big bang – that dark-matter theories did not predict (Astrophysical J. Lett. 2000 541 L33).

The Institute of Physics is to launch its first major inquiry into university education in the UK for ten years. It will address many of the changes that have affected university physics departments since the Institute published a report in 1990 that led to the new four-year MPhys degrees. The panel carrying out the inquiry is being chaired by Institute president Sir Peter Williams.

Norwegian physics is strong in astronomy high-energy physics and space physics, hut there is little research in semiconductor physics, solid-state magnetism, low-temperature physics, nonlinear optics, femtosecond spectroscopy or biological physics. That is the conclusion of a recent evaluation carried out for the Research Council of Norway by an international committee chaired by Örjan Skeppstedt, director of the ManneSiegbahn Laboratory in Stockholm.

Do you enjoy an intellectual challenge? Do you know a little about neurobiology? If the answer to both questions is "yes", then you could he in line to win $500 and a handheld computer. All you have to do is discover how an artificial neural organism works, based on details posted on a Web site and your own deductive reasoning. But you have to do it fast. The competition closes on 1 December.

When two Russian cosmonauts, Sergei Krikalyov and Yury Gidzenko, and an American astronaut, Bill Shepherd, become the first permanent residents of the International Space Station later this month, one of their first tasks will be to prepare the station for the arrival of its science module, Destiny, in January. Although scientific research is not the primary purpose of the station, which will take four more years and 35 more launches to complete, a range of experiments are planned.

News in brief articles November 2000

In Tom Wolfe's account of the early days of the US space programme, The Right Stuff, he describes how astronaut Scott Carpenter almost ran out of fuel on a test flight: "Carpenter's flight agenda had been loaded with Larry Lightbulb experiments. The scientists, lowest men in the NASA pecking order up to now, had been given their heads on this flight...Carpenter had taken all this Mad Professor stuff seriously, and that was what led to his problems." The conclusion among the astronauts, writes Wolfe, was that "all this science nonsense could wait".

The Nobel committee for physics is to be congratulated on the choice of this year's winners (pp5–6). Prizes for the pioneers of integrated circuits, high-speed electronics and semiconductor lasers (the only one of the trio to be predicted by Physics World last month) may have been long overdue, but in a climate where the ability of physics to contribute to wealth creation and economic security is increasingly being doubted, the timing could not be better.

From the pure beauty of general relativity to modern high technology, physics is a fascinating and worthwhile subject, leading to both vast new industries and far-reaching speculations about the world in which we live. However, physics does not necessarily need advanced equipment or the latest supercomputers for worthwhile research to be carried out. In some cases it is possible to carry out satisfactory experimental physics even in fairly simple laboratories.

Scientists are of two minds about metaphors and analogies. Early last century, the physicist Pierre Duhem regarded metaphors and analogies as important psychological, explanatory and educational tools for scientists, but insisted that they played no role in the structure of science itself. Many still agree. "When thinking about nature," the zoologist Richard Lewontin wrote recently in Natural History (April 2000 p94), "beware of metaphors."

It was with mixed feelings that I read your story about the crisis in the recruitment of physics teachers in the UK (October p13). I am a former physics teacher in my mid-40s. I went into teaching after 12 years in industry, investing a year of my time to do a teacher-training course only eight years ago. I enjoyed teaching young people, and past pupils and their parents have been kind enough to say that I was one of their best teachers.

In her article on "space weather", Janet Luhmann describes the effect that the solar wind and the Sun's magnetic field have on the region beyond the Earth's stratosphere and discusses the damaging consequences that the intense bursts of solar radiation that occur during "magnetic storms" can have on Earth (July pp31–36).

The number of popular-science books continues to increase. This is generally seen as a good thing, but I am not so sure. Laypeople who read too many of these books will think that they understand physics. In fact, anyone who can derive and test the distance–time–velocity relations of uniformly accelerated linear motion inevitably understands the basis of the subject more deeply.

I should like to clarify some of the points raised by Jeff Hughes in his review of my book Rutherford: Scientist Supreme (October p50). One of my goals was to promote Rutherford not as a "role model for budding scientists", as Hughes suggests, but as a role model for New Zealand children in whatever field they are interested in and for which they are prepared to work hard. Indeed, the Stout Trust has donated a copy of the book to the library of every intermediate and secondary school in New Zealand. Hughes also says that my emphasis on Rutherford's life in New Zealand leads to a "somewhat skewed account". But while some 40 books have been written about Rutherford, his formative years in the country have never been studied before.

Malcolm Crick appears to be puzzled by the meaning and etymology of the name "Chernobyl" (October pp51–52). Having translated many Russian scientific papers into English over the years, it has always seemed to me to be quite simple. The key is to pronounce Chernobyl correctly. I have never believed that the pronunciation "Churr-nobble", which has been consistently used by the British media since the accident in 1986, is correct. I think it should be "Kairno-peel", which makes very good sense, meaning "nuclear pile" – from the German word "Kern" and the French word "pile".

Superfluids are among the most peculiar and counterintuitive of all materials. They have no viscosity, which allows an object travelling in a pure superfluid to move without friction. Similarly, they can flow effortlessly through narrow channels and pores that are virtually impermeable to conventional liquids. Superfluids are relatively rare and inaccessible, with only two known examples in liquids: helium-3 and helium-4. Now Peter Toennies and co-workers at the Max Planck Institute of Flow Research in Göttingen and the Russian Academy of Sciences in Moscow have revealed convincing evidence for superfluidity in liquid hydrogen (S Grebenev et al. 2000 Science 289 1532).

Various forms of magnetoresistance – a change in the electrical resistance of a material or structure that is caused by a magnetic field – have captured the attention of many scientists over the past 12 years. The first observations of giant magnetoresistance in 1988 were followed by the discovery of colossal magnetoresistance in 1993. Now Stuart Solin of the NEC Research Institute in Princeton and co-workers have discovered an even larger form of magnetoresistance (S A Solin et al. 2000 Science 289 1530). Moreover, this geometric effect was discovered in non-magnetic materials at room temperature.

Nature teasingly reveals its secrets. One of its most profound is superconductivity. The sudden loss of all resistance to electric current never fails to startle and inspire novice researchers. Once the domain of a relatively small research community, this remarkable phenomenon became widely accessible with the discovery of high-temperature cuprate superconductors. Now a team of researchers in Israel has uncovered evidence for the first non-cuprate material that superconducts above liquid-nitrogen temperatures (Y Levi et al. 2000 Europhys. Lett. 51 564).

The natural and technological worlds operate by employing waves of all sorts: electron, electromagnetic, acoustic and so on. These waves can be manipulated by blocking their propagation in certain frequency regions called gaps, while allowing the propagation in other regions called bands. Semiconductor technology, for example, is based on electron-wave propagation in the so-called conduction and valence bands. And a new technology is emerging based on periodic structures that have bands and gaps for electromagnetic waves.

The mathematics of quantum theory is based on operators rather than numbers. In optics this simple fact allows statistical quantities, such as the fluctuations in the electric field of a light beam, to be smaller than is allowed by classical physics. Experiments that measure these quantities can generally be divided into two types, depending on whether they measure the wave or the particle properties of light. This is in line with the "complementarity principle" of quantum mechanics, which states that the wave and particle aspects of a system cannot be observed at the same time.

A revolution is taking place in cosmology. New ideas are usurping traditional notions about the composition of the universe, the relationship between geometry and destiny, and Einstein's greatest blunder. As numerous observations and experiments reshape the field, many cosmologists are exploring the possibility that the vast majority of the energy in the universe is in the form of a hitherto undiscovered substance called "quintessence".

The possibility of extra dimensions, beyond the three dimensions of space of our everyday experience, sometimes crops up as a convenient, if rather vague, plot in science fiction. In science, however, the idea of extra dimensions has a rich history, dating back at least as far as the 1920s. Recently there has been a remarkable renaissance in this area due to the work of a number of theoretical physicists. It now seems possible that we, the Earth and, indeed, the entire visible universe are stuck on a membrane in a higher-dimensional space, like dust particles that are trapped on a soap bubble.

Hari Seldon, the fictional creator of "psychohistory" in Isaac Asimov's "Foundation" series of novels, predicts the imminent demise of the First Galactic Empire after a 12 millennium run and establishes the Foundation on a planet at the galaxy's edge. In doing so, he initiates a chain of events aimed at reducing the duration of the dark ages between the first and second empires from a disastrous 30 millennia to a tolerable one. Seldon's plan is based on psychohistory – "that branch of mathematics which deals with the reactions of human conglomerates to fixed social and economic stimuli".

A hundred years ago the British government made the far-sighted decision to build a national laboratory for physical measurements. The laboratory was well financed from the start. It was able to build state-of-the-art buildings and to commence work in a variety of areas, without the constraints of inadequate funding or government intervention. The high salaries that it was able to pay its staff enabled it to attract the best scientists of the day. As a result, Britain achieved world dominance across a range of technologies for industry.

What can modern science and particularly quantum theory say about consciousness? What is the nature of consciousness? What is the connection between perennial philosophies, such as Zen Buddhism, and modern science, and what do they say about consciousness? How does the individual fit into the large scheme of things?

Ambition can be a dangerous thing. There you are, a moderately successful researcher, publishing papers and minding your own business, when one day you wake up to find that you have become a strategy manager in a large corporation. Not for you the joys of discovery – the only compensation is a management bonus that might enable you to procure a better class of sleeping partner.