Posts by: Hamish Johnston

Physics World 2015 Focus on Vacuum Technology is out now

By Hamish Johnston

PW_VAC-15cover-200

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.

(more…)

Posted in General | Tagged | Leave a comment | Permalink
View all posts by this author  | View this author's profile

Quantum mechanics in a cup of coffee, hamming it up to the space station, the laws of political physics and more

 

By Hamish Johnston and Michael Banks

Physicists tend to drink lots of coffee so I wasn’t the least bit surprised to see the above video of Philip Moriarty explaining quantum mechanics using a vibrating cup of coffee. Moriarty, who is at the University of Nottingham, uses the coffee to explain the physics underlying his favourite image in physics. You will have to watch the video to find out which image that is, and there is more about the physics discussed in the video on Moriarty’s blog Symptoms of the Universe.

(more…)

Posted in The Red Folder | Tagged , , , | 1 Comment | Permalink
View all posts by this author  | View this author's profile

Browsing the Milky Way at the IAU General Assembly in Honolulu

 

Artist's impression showing the Milky Way over Hawaii

Kai‘aleleiaka: artist’s impression showing the Milky Way over Hawaii. (Courtesy: IAU)

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.

(more…)

Posted in General | Tagged , | Leave a comment | Permalink
View all posts by this author  | View this author's profile

Re-examining the decision to bomb Hiroshima

Hiroshima Peace Memorial

Not forgotten: The Hiroshima Peace Memorial is dedicated to the 140,000 people killed in the city. (Courtesty: iStockphoto/Colin13362)

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.

(more…)

Posted in General | Tagged | 10 Comments | Permalink
View all posts by this author  | View this author's profile

Faraday explodes in court, NIST is entangled in dance, and Oliver Sacks’ periodic table

 

By Hamish Johnston and Michael Banks

You may remember back in 2013 when researchers at the National Institute of Standards and Technology (NIST) in the US entangled the motion of a tiny mechanical drum with a microwave field for the first time ever. Not content with that feat, NIST physicist Ray Simmonds, who was involved in the work, has now made a dance about it (but no song, yet). Teaming up with choreographer Sam Mitchell, the duo has created a modern dance piece entitled Dunamis Novem (“The chance happening of nine things”). Featuring four dancers, their movements are based on nine quantized energy levels of a harmonic oscillator – like the microscopic drum in the NIST work. For each level, Mitchell created corresponding dance actions, while Simmonds created a random-number generator – to add some “quantum randomness” – for the sequence of levels that the dancers perform at. If the dancers happen to touch each other, their actions become synchronized, which can then only be broken by a beam of light – demonstrating that a measurement collapses the entanglement.

NIST has published a Q&A with Mitchell and Simmonds with links to videos of the dance and the animations of the corresponding energy levels of the harmonic oscillator. A video of the first half of Dunamis Novem is shown above and a video of the entire dance is also available.

(more…)

Posted in The Red Folder | Tagged , , , | 2 Comments | Permalink
View all posts by this author  | View this author's profile

The Magnus effect in action, destroying the world, an astrophysicist camps out in Manchester and more

 

By Hamish Johnston and Michael Banks

This week’s Red Folder opens with a fantastic video (above) from the folks at Veritasium. It involves dropping a spinning basketball from the top of a very tall dam in Tasmania and watching as the ball accelerates away from the face of the dam before bouncing across the surface of the water below. In comparison, a non-spinning ball simply falls straight down. This happens because of the Magnus effect, which has also been used to create flying machines and sail-free wind-powered boats. The effect also plays an important role in ball sports such as tennis and is explained in much more detail in our article “The physics of football”.

(more…)

Posted in The Red Folder | Tagged , , , | 7 Comments | Permalink
View all posts by this author  | View this author's profile

The search for alien life gathers pace

Alien hunters: Yuri Milner (left) and the great and the good of astronomy announce the Breakthrough Initiatives (Courtesy: Breakthrough Initiatives)

Alien hunters: Yuri Milner (left) and friends announce the Breakthrough Initiatives. (Courtesy: Breakthrough Initiatives)

 

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.

(more…)

Posted in General | Tagged | 4 Comments | Permalink
View all posts by this author  | View this author's profile

The STEM jobs paradox rumbles on

Illustrations of jobs versus candidates

On balance: STEM shortages and surveys.

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.

(more…)

Posted in General | Tagged | 1 Comment | Permalink
View all posts by this author  | View this author's profile

ILC Science Club, science fiction versus science fact and siblings in physics

 

By Hamish Johnston

At the end of next week millions of children in England and Wales will start their summer holidays and many parents will now be scrambling to find activities to keep their little dears occupied. Physics World can recommend a virtual trip to ILC Science Kids Club courtesy of the Tokyo Cable Network and Japan’s Advanced Accelerator Association. ILC stands for International Linear Collider, which is one of several proposed to take over when the Large Hadron Collider is eventually retired. In the first video of the series, a boy called Haru learns why scientists are keen on building accelerators from his Uncle Tomo. The video is in Japanese with English subtitles, so as well as learning about particle physics, your little tykes might even pick up a little Japanese.

(more…)

Posted in The Red Folder | Tagged , , | Leave a comment | Permalink
View all posts by this author  | View this author's profile

The trebuchet challenge, the physics of ketchup bottles plus sage advice for budding science-fiction writers

 

By Hamish Johnston

“A surprising amount of stuff gets wasted every year because consumers can’t get it out of the packaging it came in,” writes Katie Palmer, who covers the science beat at Wired. In her article “The physics behind those no-stick ketchup and mayo bottles”, she explains how the company LiquiGlide has developed its slippery coating for the insides of bottles. The challenge was to create a permanently wet coating that would stick to the inside of the bottle but not mix with the liquid foodstuff – and it also has to be safe for human consumption.

LiquiGlide spun out of the lab of Kripa Varanasi at the Massachusetts Institute of Technology and has just announced that an international food-packaging supplier will be using the coating on its mayonnaise bottles. You can watch a demonstration of the coating in the video above.

(more…)

Posted in The Red Folder | Tagged , | 1 Comment | Permalink
View all posts by this author  | View this author's profile