Category Archives: General
By Hamish Johnston
Fusion power, redefining the kilogram and mimicking the Martian surface are three exciting areas of science and technology that are benefiting from the latest vacuum equipment. In our latest Focus on Vacuum Technology, which you can read free of charge, Christian Day of the Karlsruhe Institute of Technology in Germany explains how new pumping technologies will be crucial to the successful operation of future fusion power plants. “Proving the power of fusion” focuses on the extraordinary vacuum challenges facing the designers of the planned DEMO reactor, which is expected to generate 2 GW of electrical power by the mid-2030s.
Today, the kilogram is defined in terms of a cylinder of a platinum–iridium alloy that was made in the 1880s. Metrology has moved on since then and all of the other SI base units are now defined in terms of fundamental constants. In “The kilogram’s constant struggle”, Stuart Davidson and Ian Robinson of the National Physical Laboratory in Teddington, UK, explain how vacuum technology is playing a crucial role in the development of new ways of defining the kilogram, one of which will ultimately be chosen as the new global standard.
By Matin Durrani
Earlier this month my colleague Hamish Johnston published a blog post about the 70th anniversary of the bombing of Hiroshima, in which he reported on a piece by the science historian Alex Wellerstein about whether that first use of a nuclear weapon for non-testing purposes was justified.
It’s a hugely contentious issue – some say that the Hiroshima and Nagasaki bombings brought to an end a conflict that might otherwise have dragged on much longer, while others claim that a detonation well away from built-up areas would have been a better deterrent. Either way, the Hiroshima anniversary served as a pertinent reminder of the long and controversial role that physicists have played in designing and creating nuclear weapons, from the Manhattan Project onswards.
However, there have been plenty of physicists who have opposed the development of nuclear arms, including the Bulletin of the Atomic Scientists, which was founded in 1945 by Manhattan Project scientists who “could not remain aloof to the consequences of their work”. Another anti-nuclear group is the UK-based Scientists for Global Responsibility, whose executive director Stuart Parkinson is a physicist. Last week it published a report calling for the UK government not to replace its submarine-based Trident nuclear deterrent.
Now, a group of 29 leading US scientists and engineers, including six Nobel laureates, has written a two-page letter to US President Barack Obama backing the deal that the US – along with China, France, Germany, Russia and the UK – has struck with Iran to limit its development of nuclear weapons and permit inspections in return for a lifting of economic sanctions.
By Andrew Silver
Can the unaided eye see the light from a single candle from 10 miles away? According to some claims on the Internet, the answer is yes – but now two scientists in the US have borrowed techniques from astronomy to show that a pair of binoculars would probably be needed.
The story behind this work began high in the Andes one moonless night when a candle was lit on the Cerro Tololo Inter-American Observatory telescope catwalk. Somebody walked 400–600 m away and said the flame was as bright as the brightest stars in the sky. Nobody wrote down any numbers.
By Hamish Johnston
Earlier this week the triennial XXIX General Assembly of the International Astronomical Union (IAU) kicked off in Honolulu, Hawaii. Founded in 1919, the IUA has about 10,000 members based in 96 countries worldwide. About 3500 astronomers are attending this year’s meeting, which runs until 14 August and is hosted by the American Astronomical Society.
A long-standing tradition of the congress is the production of a daily newspaper for delegates and 2015 is the first year that an electronic version is available to the general public. You can catch up with all the daily news by downloading a copy of Kai‘aleleiaka, which is pronounced “kah EE ah lay-lay-ee AH kah” and means “the Milky Way” in Hawaiian.
By Hamish Johnston
Today marks the 70th anniversary of the bombing of Hiroshima – the first time that a nuclear weapon was used in war. Many argue that the bombing of Hiroshima, and three days later Nagasaki, was a necessary evil that saved hundreds of thousands of lives by ending the war and avoiding an allied invasion of Japan.
Over on The Nuclear Secrecy Blog, the science historian Alex Wellerstein asks “Were there alternatives to the atomic bombings?”. Wellerstein argues that the choice facing the US in 1945 was not as simple as whether to bomb or to invade. He points out that some physicists working on the Manhattan Project – which built the bombs – argued for a “technical demonstration” of the weapons.
In June 1945 the Nobel laureate James Franck and some colleagues wrote a report that argued that the bomb should first be demonstrated to the world by detonating it over a barren island. Wellerstein surmised that “If the Japanese still refused to surrender, then the further use of the weapon, and its further responsibility, could be considered by an informed world community”. Another idea being circulated at the time was a detonation high over Tokyo Bay that would be visible from the Imperial Palace but would result in far fewer casualties than at Hiroshima, where about 140,000 people were killed.
On the other hand, Wellerstein points out that Robert Oppenheimer and three Nobel laureates wrote a report that concluded “we can propose no technical demonstration likely to bring an end to the war; we see no acceptable alternative to direct military use”. This report was written for a US government committee, which decided to use the weapon against a “dual target” of military and civilian use.
By Matin Durrani
Mention the two words “science policy” and most physicists’ eyes will probably glaze over. Most of us dream of discovering a new planet or finding the Higgs boson – not poring over budget spreadsheets, championing science to politicians or commenting on legislation.
But science policy is vital in today’s world, which depends hugely on scientific research and in the cover feature of the August issue of Physics World, which is now out, Len Fisher and John Tesh offer 12 practical tips for scientists who want their ideas incorporated into science policy. You’ll be intrigued by what the two authors have to say.
Elsewhere in the issue, as my colleague Tushna Commissariat explains in the video above, there’s a great feature based on an interview with the French physicist Hélène Langevin-Joliot – the granddaughter of Marie Curie. In the article, Langevin-Joliot explains what’s known as the “Curie complex” and gives her own tips for scientific success. Langevin-Joliot didn’t suffer from the complex herself, but she acknowledges that it is a big problem for others and, these days, spends her time actively promoting careers for women in science
By Tushna Commissariat
This week, India is mourning the loss of an esteemed leader – the country’s 11th president APJ Abdul Kalam, who died on Monday. Kalam was in office from 2002 to 2007 and enjoyed country-wide popularity, even post his presidency. Described by US president Barack Obama as a “scientist and a statesman” in his eulogy, Kalam was a physicist and an aeronautical engineer before he turned to politics, first acting as a science administrator and adviser for nearly four decades before his office run. Indeed, he was heavily involved in India’s nuclear tests and its military missile programme, earning him the moniker of “Missile Man”. In 2007 he was awarded the Royal Society’s King Charles II Medal, which is “awarded to foreign heads of state or government who have made an outstanding contribution to furthering scientific research in their country”.
By Hamish Johnston
Earlier this week in London the billionaire physics enthusiast Yuri Milner joined forces with some of the biggest names in astronomy and astrophysics to announce a $100m initiative to search for signs of intelligent life on planets other than Earth. The money will be used to buy time on a number of telescopes to search for radio and optical signals created by alien civilizations.
By Hamish Johnston and Margaret Harris
Are countries such as the UK, the US and Canada suffering from a shortage of scientists and engineers, or are scientists and engineers struggling to find jobs there? Our US correspondent Peter Gwynne reports that, according to a recent survey, physicists in that country can expect to be rewarded with handsome salaries if they work in industry – which suggests that their skills are in great demand. However, over in the New York Review of Books, an article on “The frenzy about high-tech talent” claims that “by 2022 the [US] economy will have 22,700 non-academic openings for physicists. Yet during the preceding decade 49,700 people will have graduated with physics degrees.”
In the past few years, Physics World has published several articles on the “STEM shortage paradox”, where reports of severe skills shortages in science, technology, engineering and mathematics (STEM) coexist with lukewarm – and sometimes borderline alarming – data on employment in these fields. Hence, conflicting reports on career prospects for physicists don’t really surprise us anymore (although this is actually slightly different to what we’ve seen before, in that rosy employment data are going up against a downbeat statement about demand, rather than vice versa). But even so, when two reports point in such different directions, it’s tempting to conclude that one of them must be wrong, or at least missing something important.
By Margaret Harris
Last night, in honour of the New Horizons mission to Pluto, I pulled out my copy of Solarquest. This classic board game was a childhood favourite of mine, and it’s basically Monopoly in space: instead of buying properties named after streets in Atlantic City, New Jersey (or London, if you’re British), you buy planets, moons and artificial satellites. Then, when your fellow players land on an object you own, you charge them rent.
Such nostalgia is all well and good, I hear you say, but what’s it got to do with New Horizons or Pluto? Well, Solarquest’s inventors clearly took their science seriously. By board game standards, there’s quite a lot of physics in it. For example, you can’t leave a planet unless you roll a number high enough to overcome its gravitational pull, and its Monopoly-like property deed cards include facts about each planet and moon as well as their prices.