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British workers at JET accept pay deal

During the 1980s the European Court of Justice in Strasbourg agreed that the British workers had been discriminated against, and in 1996 the court ordered the European Commission to settle the case. The workers can now expect to receive between £70000 and £100000 each.

A major reason for the settlement is the collapse of the proposed $10bn International Experimental Fusion Reactor (ITER). This next-step fusion project would have continued the work of JET and other fusion plasma experiments in Europe, Japan and the US. However, last summer the US pulled out of ITER, and the three remaining partners – the EU, Russia and Japan – agreed to concentrate on a smaller and cheaper version of the reactor. Thus by extending JET’s lifetime by another three years, fusion researchers will be able to study some of the science and engineering challenges behind a smaller reactor.

However, a pre-condition for any extension of JET was that the salary dispute had to be settled first. Now that a deal has been provisionally agreed, the future of JET looks assured.

The brain is ‘classical’

Nearly all the quantum models of the brain depend on how long the brain can keep quantum coherence. Penrose argues for example, that microtubles – small hollow cylinders that help cells keep their shape in the brain – operate like a quantum computer and can keep information stored as ‘quantum waves’ for long periods of time. In other words, they are the sites of ‘human consciousness.’

For this to work, the decoherence time – the length of time that a quantum wave can remain coherent before it collapses – for microtubles must be at least 1 second. However, Tegmark claims that Penrose has neglected the effects of distant ions on the decoherence time. These ions are found in the material surrounding the microtubles and in other neurons. According to his calculations, the decoherence time is 10^-13 seconds, which is not long enough for quantum effects to influence the brain. This proves, says Tegmark, ‘that there is nothing fundamentally quantum-mechanical about cognitive processes in the brain’.

Physics research to get Lottery funding

Jeremy Newton, chief executive of NESTA, says that the fund will support projects across the whole spectrum of science, art and technology, particularly interdisciplinary research. But with such a wide remit and limited resources, funding will have to be highly selective. A key feature of NESTA, explains Newton, will be its willingness to take risks and its acceptance that not every horse it backs will be a winner.

Terry Clark of Sussex University has won £90 000 from NESTA for his research on superconducting quantum interference devices (SQUIDs). Clark hopes to use SQUID rings to form the basis of quantum computers. Such machines would exploit the superposition of quantum states by carrying out many operations simultaneously, thereby far outperforming conventional classical computers. But Clark says that actually building a quantum computer will be extremely difficult and that practical pay-off is probably many years away.

Newton hopes that NESTA funding will allow researchers like Clark to develop ideas to the stage where they can attract money from venture-capital companies, which rarely invest less than £1m at a time. To this end NESTA will award grants worth between £5000 and £50 000 every year to inventors and researchers. It will also support individuals over several years through fellowships worth between £25 000 and £75 000, in order to give them the chance to develop original ideas in the first place. In addition, there will be support for education and the public understanding of science.

Almost 500 applications were made to NESTA’s pilot scheme. Projects that received funding covered dance, young entrepreneurs, computer games, scanning electron microscopy and a scheme to increase collaboration between artists and scientists. Also selected was a project that will allow mathematicians from Cambridge University to teach pupils from disadvantaged schools using videoconferencing. The scheme could be used in the future to teach physics.

Astronomers attempt to reclaim the skies

The meeting, “Preserving the Astronomical Sky,” was held in Austria a few days before UNISPACE III, a major conference sponsored by the United Nations (UN) that will look at the impact and influence of space research and industry in the 21st Century.

Light pollution has become an increasing problem in recent decades, with the resolution of many telescopes being degraded by light from nearby towns and cities. Radio interference from both ground- and space-based communication stations has also caused some radio telescopes to be closed down for hours upon time. There are also over 100,000 objects larger than 1 cm in low Earth orbit that can interfere with astronomical observations.

To combat the problem astronomers have called for the establishment “radio-quiet zones” where radio observatories can be protected from interference, and for urban planners to reduce “light leakage” when they build new houses and roads. They also want future space projects that might degrade the space environment at any electromagnetic wavelength to be subjected to an environmental impact assessment before they are approved.

“These problems are global in scale and effect, and long-term in nature,” said Anderson. “International efforts are needed to resolve them, as the UN already has done for the oceans and the Antarctic.”

Newspaper heightens collider fears

The RHIC seeks to recreate the primordial “soup” of particles that existed immediately after the big bang and from which everyday matter formed. Today quarks only exist inside strongly interacting particles, called hadrons, where they are held together by gluons. By colliding two beams of relativistic heavy ions – such as gold ions travelling near the speed of light – the physicists using RHIC hope to create matter with an energy density so high that the quarks and gluons will co-exist as a plasma

The present controversy started with a letter in the July issue of Scientific American that asked if the collisions at RHIC could produce mini-black holes. This was followed up by the Sunday Times on 18 July. The newspaper reported that RHIC might produce mini-black holes and strange matter, and that Brookhaven had “set up a committee of physicists to investigate whether the project could go disastrously wrong.” An accompanying editorial accused scientists of acting first and asking questions “later.”

Since then Brookhaven has been besieged by the media and the public. “We’ve had emails, telephone calls and letters from all over the world including India, Pakistan, Australia and Europe,” said a Brookhaven spokesperson. On 19 July Brookhaven director John Marburger responded with a press release: “These issues have been raised and examined by responsible scientists who have concluded that there is no chance that any phenomenon produced by RHIC will lead to disaster.”

Jonathan Leake, who wrote the Sunday Times story, believes that Brookhaven only has itself to blame for the outcry. He also points out that the article quotes physicists as saying that the risk is small. “Brookhaven mishandled their response to the fears on this issue,” he told PhysicsWeb.

Shuttle launches X-ray telescope

X-ray observations with Chandra will complement infrared images from the Hubble Space Telescope and higher-energy observations by the Compton Gamma Ray Observatory. Chandra will have a resolution that is 8 times better than any previous X-ray telescope, while its sensitivity will be 20 times better. It will detect X-rays from stellar flares, exploding supernovae, white dwarfs, neutron stars and other astrophysical objects.

Unlike the Hubble Space Telescope – which is expected to last over 15 years – Chandra will have a relatively short life of 5 years. The X-ray telescope’s high orbit – designed to avoid the intense radiation of the Van Allen belts that surround the Earth and can damage sensitive instruments – means that the space shuttle cannot return for maintenance and repairs.

George Brown, strong supporter of US science, dies

Brown joined the science committee in 1965 and became chairman in 1990, losing his position when the Republicans gained control of Congress in 1995. The current chairman of the committee, James Sensenbrenner, was one of the many people to pay tribute to Brown. Others included President Clinton, vice-president Al Gore and NASA chief Dan Goldin.

“Whether it was protecting a science account from attack or pushing the newest area of research, George was a true friend to the science community,” said Sensenbrenner. “Even after sitting through hundreds of presentations by researchers, George never lost a genuine delight in hearing of new breakthroughs.”

Dubna lab finds second isotope of element 114

Until the Dubna experiments all artificial superheavy nuclei had half-lives that were measured in milliseconds. However, the most stable nuclei on the island of stability are predicted to have half-lives of years. The first isotope of element 114 to be discovered – the one with 175 neutrons – has a half-life of 30 seconds, while its lighter sibling has a half-life of 5 seconds. Elements 116 and 118 are much less stable, decaying in milliseconds.

The first isotope of element 114 was created by colliding plutonium-244 and calcium-48 nuclei. Creating enough of these isotopes for the experiments was difficult because plutonium is highly toxic and radioactive, while calcuim-48 is extremely rare. There is also only a very small probability that superheavy elements will be created and then survive in the collisions. In the first set of experiments at Dubna, only one event out of a total of 5.2 x 10¹⁸ events over 34 days resulted in element 114. The lighter isotope was produced by colliding calcium-48 and plutonium-242. During this run some 7.5 x 10¹⁸ calcium ions were directed at the plutonium target over a period of 32 days, and 4 events were detected.

EPS high-energy prize goes to ‘t Hooft

‘t Hooft has made several crucial contributions to the Standard Model of particle physics. In 1967 Salam and Weinberg showed how to unify the weak and electromagnetic interactions – two of the four fundamental forces of nature – into a single electroweak force. In 1971 ‘t Hooft showed that the electroweak force was renormalizable – in other words, that the infinities in the theory could be removed. ‘t Hooft has also made major contributions to our understanding of quantum chromodynamics, the theory that describes the strong nuclear force, and his work has had a major influence on string theory – currently the leading candidate for a theory that will unify all four forces.

First for single-photon measurements

Photons are traditionally detected by converting their energy into an electric signal, which destroys the photon in the process. An additional problem in quantum measurements is that if one variable – say the position – is measured accurately, then the consequent uncertainty in another, incompatible variable – the momentum in this example – will mean that future measurements of the position will yield different results. For photons the intensity (or photon number) and the phase are related through the uncertainty principle. Although various so-called quantum non-demolition (QND) measurement schemes have been demonstrated in which the photon intensity can be measured without destroying the photons, these experiments only work for macroscopic photon fluxes. Michel Brune, Jean-Michel Raimond, Serge Haroche and co-workers in Paris have now performed the first QND measurement on a single photon.

The Paris team used lasers to first select rubidium atoms with a very well-defined velocity, and then prepare them in a highly-excited so-called Rydberg state. The atoms were then passed through the niobium cavity, which can store a single microwave photon for up to 1 millisecond. The experiment is designed such that the energy of the microwave photon is the same as the energy difference between two Rydberg in the atom.

If there is no photon in the cavity, nothing happens to the atom. If there is one photon, however, the phase of the wave function describing the atom is changed and this can be measured using interference techniques. These techniques can also detect if the photon is in a quantum superposition of zero-photon and single-photon states. If a second atom is sent through the device, it yields the same result as the first one, showing that a QND measurement has been made. It is not possible to extend the technique to higher numbers of photons but it could be used to make a quantum logic gate.

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