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Physics on film

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May 2010 Archives

Party curtailed at the Tevatron

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View of the Tevatron at Fermilab. (Image courtesy of Fermilab)

By James Dacey

With the sheer scale of its machinery and its extensive international collaborations, accelerator physics is now a highly visible part of mainstream science. A recent episode at Fermilab reminded me, however, that the scientific results could never be as clear-cut as the facilities that produced them. I couldn’t help but feel a little bit frustrated by this, but perhaps that says more about my short concentration span.

Earlier this week, we reported new findings from Fermilab’s D0 experiment, which claimed to have gathered the strongest evidence yet for CP violation beyond the Standard Model. CP violation helps to explain the fundamental difference between the behaviour of a particle and its antiparticle. It explains why matter survived in the universe after the Big Bang, when matter and antimatter were created in equal amounts and should have annihilated completely.

So as you can see the implications of this research were fairly humongous. Hence physicsworld.com and a whole load of other sites covered the story.

However, last Monday – without us realizing – a rival experiment at the Tevatron had already poured cold water on the D0 celebrations by saying that the results were void. Let me explain.

D0 had looked for asymmetry in the production of muons from the decay of B mesons and anti B mesons, and they reported a CP violation that was 3.2 standard deviations larger than what is predicted by the Standard Model.

The particle physics community got very excited because their results had included decent measurements, for the first time, of the decay of Bs mesons, which theorists have long touted as an excellent place to look for CP violation. It seemed that the physics was finally moving beyond the Standard Model.

But before D0 had time to wind down their celebrations, Gavril Girgiu of the CDF experiment was in Turin addressing a particle physics conference about the CDF analysis of the same meson decays. The difference was that CDF had seen nothing out of the ordinary in their results, and their sample size was twice as large – from 5.2 femtobarn of Bs decays, they record CP violation that is within 0.8 standard deviations of the Standard Model.

Now, don’t get me wrong here. I fully realize that experimental physics can only ever move forwards by the proposition of new phenomena followed by its confirmation by other experiments. But, given the expectation that surrounds particle physics – fuelled largely by the high profile of its facilities – I just couldn’t help but feel a bit frustrated by these events. It was just a reminder that despite all the exciting questions and mind-blowing implications of particle physics, the real science so often boils down to more mundane concepts like statistical significance.

Perhaps there is a better way for the particle physics community to communicate that this part of the science can be fun too?

The danger is that people like me, who are intrigued by this weird and fascinating area of science, have come to expect every new result to be as certain as the facilities that have produced them.


By Matin Durrani

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Martinus ? ? Veltman

It’s Friday afternoon here at Physics World HQ, and my colleagues and I were just looking at the programme for the 2010 Nobel Laureate Meeting in Lindau, Germany — an annual bash where Nobel prize-winners and students from around the world meet up to chew the fat and think big thoughts.

This summer’s meeting features laureates from all disciplines but there are stacks of physicists among them.

The programme looks great — but what caught our eye was that German organizers have very kindly included the middle names of all the laureates who are speaking.

So here’s our quiz for today. Just for fun, it’s your job to guess the middle names of the following laureates. In each case we’ve given a clue.

John Mather — shared the 2006 prize with George Smoot for their work on the anisotrophy of the cosmic background radiation (CMB)
Clue: think English Civil War.

George Smoot — see above
Clue — think The Great Gatsby

Robert Wilson — shared the 1978 prize for discovering the CMB
Clue — think a US president with the same last name.

James Cronin — shared the 1980 prize for symmetry violation in K-mesons
Clue — think a Nobel prize-winning biologist with the same first name.

Martinus Veltman — shared the 1999 prize for electroweak interactions
Clue — he has two middle names. Er, think Latin.

Robert Laughlin — shared the 1998 prize for fractional quantum fluids.
Clue — what he does if he puts money on it.

Add your comments below. I’ll update the blog in a day or two with the answers. In the meantime, no Googling — where’s the fun in that?

Update: Monday 31 May
OK so here are the answers: John Cromwell Mather, George Fitzgerald Smoot, Robert Woodrow Wilson, James Watson Cronin, Martinus Justinus Godefriedus Veltman, Robert Betts Laughlin.

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What’s next, a quantum commentator? (Courtesy: UKZN)

By Hamish Johnston

What do quantum cryptography and the World Cup have in common?

The answer is that both will feature at the Moses Mabhida Stadium in Durban, South Africa, next month.

The eThekwini Municipality, which includes Durban, and the Centre for Quantum Technology at the University of KwaZulu-Natal (UKZN) have joined forces to install a quantum-cryptography secured telecoms link between the football stadium and the FIFA World Cup Joint Operation Centre in Durban.

The system includes a dedicated optical fibre connection and the Cerberis quantum encryption system. Developed jointly by Australia’s Senetas and Geneva-based idQuantique, Cerberis is a quantum key distribution (QKD) system that allows two parties to secretly share random strings of bits that are used to encrypt and decrypt messages.

The bits are encoded into a stream of photons that are sent down a dedicated fibre. Anyone trying to intercept the string must make a measurement on the photons. Quantum mechanics dictates that a measurement will cause an irrevocable change to the photons, which would alert the two parties to the presence of an eavesdropper.

According to UKZN physicist Abdul Mizra, the system will be used to ensure the secure transmission of voice and data, including e-mail.

So why do World Cup organizers need such a high level of security?

“With all high-profile events, there is a security concern with regards to dignitaries and teams”, explained Mizra.

I suppose that’s fair enough, given that Barack Obama might put in an appearance.

However, avid physicsworld.com readers will recall that just last week Canadian physicists claimed to have hacked an idQuantique system.

You can read more about the quantumStadium and the related quantumCity project here.

By Margaret Harris

I’m not talking about physical look-a-likes here, but researchers who share your name – and thus might be mistaken for you when someone searches the scientific literature.

In my case, I can’t say that the prospect worries me very much. Although I am only the fifth-most-cited “M L Harris” on the ISI Web of Knowledge – lagging behind a Mary L Harris who studies bowel disease; a Meghan L Harris who works for the Iowa Department of Public Health; and two unspecified M L Harrises who study lung problems in London and environmental toxins in Canada – my doppelgangers and I work in such different fields that it would be hard to confuse us.

However, I can accept that modern-day A Einsteins – of whom there are a surprisingly large number – might feel differently on the issue. The same goes for a physicist I met at a conference once: his name was Slobodan Milosevic.

Name confusion is a particular concern for people whose names have multiple accepted English transliterations, like Xu/Hsu or Müller/Mueller. Different publishers’ conventions can mean that such people become, in effect, their own scientific doppelgangers, with multiple database identities that actually refer to the same person. A separate-but-related problem arises when researchers change surnames after marriage, or add a second initial. Stephen Hawking, for example, publishes as both “Hawking S” and “Hawking S W”. Although he’s probably too famous to care now, lesser-known researchers can suffer if name confusion means that hiring committees and potential collaborators get an incomplete picture of their work.

To address this problem, various organizations have sponsored initiatives that attempt to
assign unambiguous identities to scientific researchers. Many scientific publishers – including IOP Publishing, which publishes physicsworld.com – are working on their internal author databases, trying to eliminate duplicate entries and create clear and accurate records of each scientist’s work.

However, the scope of such databases is usually limited to a single publisher. There are a few broader efforts out there, including the American Institute of Physics’ Uniphy service, but so far, there is no “global, cross-sector, cross-institutional system that research institutions and all types of publishers can share”; like the one this article from Chemical and Engineering News suggests is needed.

But is such a vast database really necessary? Or are scientific doppelgangers a minor problem, one that could be solved with better record-keeping on a smaller scale?

Next stop: Seattle

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By Michael Banks in Miami, Florida

So that was this summer’s American Astronomical Society (AAS) meeting. We had some nice talks about NASA’s Solar Dynamics Observatory (SDO), the CoRoT exoplanet hunter and the Herschel satellite as well as how to destroy asteroids and unexpected results from research into supermassive black holes.

I would say it was SDO that stirred the most interest, and talks about the mission were usually given to a packed auditorium. Indeed, SDO’s booth in the exhibition centre was always busy with people staring in awe at the new images of the Sun the satellite has recently produced.

One thing you always probably take away with you when attending talks on astronomy is the sheer scale of the universe. For example, in a talk on Herschel today (see previous entry) even when zooming into an average image taken by the satellite three or four times there are still more than 6000 galaxies in the picture possibly containing millions of stars and thousands of planets.

And that brings in another aspect of astronomy – handling the huge amounts of data that missions are now producing second by second. The Wide-field Infrared Survey Explorer (WISE), for example, is taking an image every few seconds transmitting terabytes of data every day. Astronomers think it will take at least 20 years before they have analysed all of WISE’s data.

Hopefully astronomers working on missions such as SDO, WISE and Herschel will be able to tell us even more about our Sun and the universe when the next AAS meeting is held in Seattle starting on 9 January. See you there!

Mapping the cosmos

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Inspecting the 3.5 wide mirror of the Herschel telescope

By Michael Banks in Miami, Florida

It seems I have something (rather tenuously, I admit) in common with the European Space Agency’s Herschel mission: we were both “born” in 1982. (Although I am not sure what else I could have in common with a space satellite.)

Goran Pilbratt from the European Space Agency (ESA) told delegates today at the 216th American Astronomical Society meeting in Miami, Florida, all about the Herschel mission that was first proposed way back in May 1982 at an ESA workshop.

Herschel features two cameras (named PACS and SPIRE) and a spectrometer (HIFI) to study star formation in our galaxy and galaxy formation across the universe.

Herschel also has a dewar of liquid helium that cools its detectors down to 2 K so that it can better measure objects in the sky in infrared via its 3.5 m wide mirror.

With 30 years invested in the instrument, you could perhaps forgive astronomers for being nervous when Herschel launched on 14 May 2009. “Herschel has no moving parts, so if there is something wrong after it launches we can’t do anything about it,” says Pilbratt.

Herschel in the end made a “perfect launch” and it even started taking data only 30 hours after launching.

But not everything has been plain sailing since then. In August 2009 HIFI stopped working and its software had to be rebooted taking around five months in total to fix.

Once back online in January, astronomers are now really reaping the rewards of HIFI. Pilbratt showed some spectroscopy data taken from the Orion constellation that contained more than 100,000 spectral lines originating from signatures of specific elements or compounds. That’s likely to take some time to trawl through.

Indeed, although the Herschel mission has only been going for around a year, astronomers have already written more than 120 research papers, which will be published in an upcoming special issue of Astronomy and Astrophysics. With another three years to run, that is likely to only be the start.

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Impact zone That’s a lot of dots

By Michael Banks in Miami, Florida

We all know the plot for the film Armageddon starring Bruce Willis. An asteroid the size of Texas is on a collision course with Earth, and the US government sends a bunch of astronauts to plant a nuclear device underneath the asteroid to blow it to pieces, thus saving humanity.

Well that is how it goes in Hollywood. But what would we do if we suddenly found a large asteroid that would hit the Earth within the next 50 years?

Last night David Dearborn, a physicist at Lawrence Livermore National Laboratory in California, gave a talk here at the 216th American Astronomical Society meeting in Miami, Florida, about the best technologies to avoid an asteroid extinction event.

In 1998 NASA started a project named Spaceguard with the aim of cataloguing 90% of all asteroids in the solar system larger than a kilometre before 1998. Currently the project has detected around 80%, mainly because, rather unsettlingly, astronomers are finding more and more of them.

Then, in 2005, Congress asked astronomers to catalogue 90% of asteroids greater than 140 m by 2020 using a number of telescopes including the Large Synoptic Survey Telescope, which is currently being built in Chile and is expected to come online in 2015.

If an asteroid is on a collision course, Dearborn says that it is important to know its composition, whether it is made up of rubble, has a solid core, or even if it is a collection of solid rocks held together by rubble.

One point Dearborn reiterated is to deflect an asteroid only when we are 100% confident that it will hit the Earth. “You have to leave it alone until you know if it is going to be a problem,” says Dearborn.

So how do you blow up an asteroid or at the very least deflect it out of harms way? One option is painting the asteroid white, which would change its albedo and slowly start to change its orbit. Given that Dearborn says it would take decades to carry out this paintball exercise on a celestial scale it is perhaps not the best option.

Another is firing a high-powered laser pulse at the asteroid, but this again would take around 6000 years to change its speed by around 1 metre per second. “The National Ignition Facility is not really designed for shooting asteroids,” says Dearborn.

So the best technique for deflecting them is via a nuclear explosion. Two options are to activate a nuclear device just before impact or attempting to strike the object with a nuclear weapon. Dearborn presented a variety of models showing how an impact would break up an asteroid depending on its composition. “Current nuclear technology could handle most possible threats,” concludes Dearborn.

I guess Bruce Willis had it right all along.

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It’s out there

By Michael Banks in Miami, Florida

We need to better understand how other stars behave before we start looking for planets orbiting around them. That was the message from astronomers speaking in a session on searching for exoplanets at the 216th American Astronomical Society meeting in Miami, Florida.

Annie Baglin from the Observatoire de Paris, France, spoke about the $160m Convection Rotation and Planetary Transits (CoRoT) mission, built by the French Space Agency, which launched in 2006.

CoRoT has two objectives: to study the solar variation in other stars as well as searching for exoplanets via a technique known as “transiting”, where a planet passing in front of the star causes its solar output as seen by the satellite to dim slightly.

Indeed, CoRoT has already had breakthroughs in studying solar variations in other stars including hot stars and red giants. Yet the science that gets the most attention is CoRoT’s search for exoplanets.

Although CoRoT lost the use of two of its detectors last year, the craft is still going strong and has managed to detect a range of exoplanets.

Most of the exoplanets spotted by CoRoT are big, hot planets such as CoRoT-3b, which has a mass 21 times that of Jupiter.

On 17 March CoRoT discovered CoRoT-9b, which has a radius similar to Jupiter and a temperature of 350 K. “If it has moons, then they would be habitable,” says Baglin. But getting to the planet is another matter as it is lies 1500 light-years away.

The biggest find to date is possibly CoRoT-7b, discovered in February 2009, which has a similar diameter and mass to Earth.

Baglin outlined in her talk how difficult it is to spot such small planets saying that constant changes in the star’s activity makes it very difficult to detect planets orbiting them. “Once we have a better understanding of a star’s cycle then we will be better placed to start to look for exoplanets,” says Baglin.

CoRoT still has another three years to run, but it has already been superseded somewhat by NASA’s Kepler mission, which launched in March 2009 to look for Earth-like planets. “Kepler will do more than what we have,” says Baglin.

By Michael Banks in Miami, Florida

The common view of black holes residing at the centre of their host galaxies might not be completely true, according to astronomer Daniel Bacheldof, from the Florida Institute of Technology.

Speaking today at the 216th American Astronomical Meeting in Miami, Florida, Bacheldof and colleagues used old data taken from the Hubble Space Telescope to show that the supermassive black hole at the centre of the M87 galaxy is slightly displaced from its centre.

The fact that a supermassive black hole – black holes that are millions or billions time the mass of the Sun – can be displaced from the centre of a galaxy is not new, but the fact that astronomers have spotted such a small displacement means that small off-sets could be more common than previously thought.

The explanation for the displacement comes from the fact that the supermassive black hole in M87 was a merger between two smaller black holes. When they merged, the emission of gravitational waves “kicked” the newly created black hole, knocking it slightly off-centre. “What we are seeing in M87 is in effect indirect evidence for gravitational waves,” notes Bacheldof.

The fact that many other supermassive black holes show similar properties to M87 could indicate that such off-sets are common in the universe. “No longer can it be assumed that all supermassive black holes reside at the centres of their host galaxies,” says Bacheldof, who is looking at other such systems to spot similar effects. Time to re-write those astronomy textbooks?

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Exhibitors at the 216th American Astronomical Meeting

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Out now: the Solar Dynamics Observatory movie

By Michael Banks in Miami, Florida

Walking into the exhibition hall at the 216th American Astronomical Meeting in Miami, Florida, it seems like this year’s must-have is a TV screen.

That is, of course, to show all the awe-inspiring images and movies that their missions are just releasing, be it from the Herschel mission, the Wide-field Infra-red Survey Explorer or the Solar Dynamics Observatory (SDO).

My favourite is the SDO booth and not just because of the free 3D glasses, but because of the quality of the images that the mission has just started to release (though they did give me a nice coaster).

The SDO booth also has two TV screens, obviously one is not enough.

With the enticement of tortilla chips, I also caught some of the poster session, which did not seem overly subscribed. Maybe people were instead enjoying the Miami sun outside.

Physics could help to replace U2 at Glastonbury

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Bono was due to grace the iconic Pyramid Stage. Credit: James Dacey

By James Dacey

The colossal Irish rock group U2 broke thousands of hearts this morning when they announced that they can no longer play their headlining slot at this year’s Glastonbury festival, a result of Bono putting his back out during rehearsals last week. The big question now is – who will replace them?

Well, if festival organizer Michael Eavis is willing to put reputations aside and choose a replacement purely on their musical similarity to U2, he may enlist the help of physicists in Brazil.

Luciano da Costa at the University of Sao Paulo and her colleagues have developed a new way of grouping music based on the subtle differences in rhythm between musical genres.

The researchers studied four musical genres – rock, blues, bossa nova and reggae – looking at 100 songs from each category, analysing the most representative sequences of each rhythm.

They then represent the rhythms as a Markov chain where the nature of each beat depends only on the preceding beat. “Basically, this means that we consider the time duration of each of two subsequent notes in order to obtain the probability transition between each type of notes (duration) in each given composition,” explains Costa.

Costa and her co-author Debora Correa are both classical pianists and they say that this has been an influence on their work. “We wanted to investigate how computing, maths and physics could be used to help us characterize and understand music and music genres,” says Costa.

So okay, I think we can be fairly certain that Michal Eavis will not involve Markov chains in selecting his U2 replacement, but this research could potentially have a far wider impact in the music industry. The researchers believe it could help to improve music platforms, such as Apple’s iTunes, which can group music to make recommendations based on the kind of music you regularly play.

You can read about the method in this open-access paper published recently in New Journal of Physics.

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Does what it says on the mouse mat

By Michael Banks in Miami, Florida

I was wondering how long it would be before I heard Will Smith’s 1998 hit song “Miami”, but I didn’t expect it while walking into a session at the 216th American Astronomical Society meeting.

This evening I attended a special symposium on the status of the Atacama Large Millimeter/submilliter Array (ALMA), which is currently being constructed in the Atacama desert in Chile.

Built by the European Southern Observatory and the US National Radio Astronomy Observatory (NRAO), when fully complete in 2013, ALMA will contain 66 antennas in total and be 100 times more sensitive than other millimetre telescopes.

ALMA will allow astronomers to study a range of phenomena including planetary and star formation.

There are currently four antennas up and working, with another 12 planned before ALMA begins science operations, which is expected to happen in early 2011.

Al Wootten, from the NRAO, who has been involved with planning ALMA for the last 20 years, says that the sensitivity together with the large bandwidth will make it a unique facility.

Speakers at the symposium were encouraging astronomers to submit ideas for using time on the telescope. “What ALMA will excel at is exploring the unexpected,” says astronomer Kelsey Johnson from the University of Virginia.

Oh, and if you are an engineer or scientist really interested in working at the ALMA telescope then they are currently recruiting and apparently want to hear from you.

Copernicus reburied by Catholic church

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By James Dacey

In his time his views may have shocked the Catholic church to its core, but on Saturday Nicolaus Copernicus was blessed and reburied by some of Poland’s highest-ranking clerics, nearly 500 years after he was laid to rest in an unmarked grave.

The ceremony came five years after what were believed to be the remains of the great astronomer were discovered beneath the floor of the cathedral in Frombork, on Poland’s Baltic coast.

Subsequent DNA analysis has confirmed the discovery after an amount of Copernicus’ hair was discovered inside a copy of his 16th century astronomy reference book Calendarium Romanum Magnum.

This short film describes Saturday’s events and how the Catholic church has tried to patch things up with the scientific community in recent years.

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The heart and soul of the universe (credit: NASA/JPL-Caltech/UCLA)

By Michael Banks in Miami, Florida

It’s a hard task to walk into a session here at the 216th American Astronomical Society meeting in Miami, Florida, and not see amazing images of the universe.

But probably one of the best was issued today by researchers working on NASA’s Wide-field Infrared Survey Explorer (WISE).

Wise is an infrared telescope that was launched in December to probe the coolest stars in the universe and the structure of galaxies at four wavelengths between 3 and 25 µm.

Costing $320m, WISE circles the Earth’s poles at an altitude of 525 km scanning the entire sky one-and-a-half times in nine months.

Ned Wright, WISE’s principal investigator, said that the satellite has already taken over a million images and surveyed about three-quarters of the sky. By the beginning of November its objectives should be complete as the solid-hydrogen coolant is exhausted.

The image shows the so-called heart and soul nebula, which lies 6000 light-years away from Earth. WISE allows us to probe this star-making factory in unprecedented detail, letting us see the gas and dust that are just about to form stars.

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Look this way: Dennis Matson telling us all about Titan

By Michael Banks in Miami, Florida

I was up bright and early this morning to attend the opening symposium at the 216th American Astronomical Meeting in Miami, Florida.

The talk was about Titan, the largest moon of Saturn, and was given by Dennis Matson from NASA’s Jet Propulsion Laboratory, a project scientist for the Cassini-Huygens mission that launched in 1997.

Huygens, a European Space Agency mission, was launched together with NASA’s Cassini satellite for a seven-year trip to Saturn. While Cassini travelled off to orbit Saturn, Huygens separated to head to Titan where it landed in 2004.

You might think Titan is a lifeless body orbiting Saturn, but Matson showed it to be anything but. With lakes of Methane on the north pole of the moon – some as large as Lake Superior – as well as evidence for plate tectonics, volcanoes and sand dunes forming on the surface, the moon is very much alive.

That is not all, as Matson flashed images of methane clouds and possible deposits of lava. There is even a claim that an ocean of liquid water exists underneath the rocky surface.

Even with our knowledge of Titan, there is still a lot to find out, including whether the moon has a magnetic field.

After five years on Titan, Huygens has now delivered most of its objectives so astronomers are planning what the next mission could be to Saturn’s sixth moon.

Matson outlined two possible missions astronomers are looking into. One is using a probe attached to a balloon that would circumnavigate the moon at an altitude of 10 km. This would allow scientists to get a global picture of the moon closer to its surface.

The other possible mission is an 85 kg probe that would float on one of Titan’s lakes, which could, for example, probe its depth.

Astronomers probably have other ideas up their sleeves, but in the end they may be constrained by technology. “We even had some people who thought about sending some sort of submarine to Titan to explore the lake,” says Matson.

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Yacht a lot of people: the opening reception at the American Astronomical Society’s meeting in Miami

By Michael Banks in Miami, Florida

“Did I just hear him say Stephen Hawking?”; said a fellow passenger queuing behind me at Heathrow airport.

I was checking into my flight to Miami as a call for Hawking was made over the loudspeaker. Of course, it could have been someone else, but I wondered if it was indeed the Cambridge-based physicist.

Could Hawking be attending the 216th American Astronomical Society (AAS) meeting in Miami I thought? Or maybe the 68-year-old theoretical physicist was instead going to Canada to take up his position as Distinguished Research Chair at the Perimeter Institute for Theoretical Physics in Waterloo.

Hawking was not on my flight, where after a 22 hour door-to-door trip I finally arrived in Miami. The AAS meeting kicked off tonight with the opening reception, so feeling a little jet-lagged, I walked over the Miami Regency Hotel where 1000 physicists will tomorrow convene for four days discussing all things astronomy.

At the reception we were reminded that we were in Miami as, every few minutes, a yacht would go past the hotel blaring loud music with people dancing on board cheering towards unsuspecting astronomers. “We don’t usually get this at the AAS,” noted one participant.

Oh, and Hawking was not in attendance at the reception tonight, so I guess he may have been on that flight to Canada after all.

Welcome to Miami

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By Michael Banks

I will be leaving for Florida tomorrow morning for the 216th American Astronomical Meeting (AAS) in Miami, which begins next week.

After promising my colleagues that I will be attending the talks and not spending most of my time blogging from Miami beach, I have just put the finishing touches on the schedule for what promises to be an intensive week of astronomy.

Top of the agenda are early results from the European Space Agency’s Herschel satellite and NASA’s Wide-field Infrared Survey Explorer as well as the status of the European Southern Observatory’s Atacama Large Millimeter/submillimeter Array, which is currently being built in northern Chile.

But that’s not all; there will also be a whole host of talks on NASA’s Solar Dynamics Laboratory as well as the continuing search for exoplanets.

So keep tabs on physicsworld.com for all the latest news from the AAS meeting.

By James Dacey

Fans of Radiohead may think this is straight out of the band’s video to their beautifully haunting single, Street Spirit (Fade Out), released back in 1996.

It is actually a demonstration of how the swallowtail butterfly manages to overcome the odds and fly in a straight line despite its unfavourable body shape. (Very Radiohead!)

Hiroto Tanaka at Harvard University and Isao Shimoyama at the University of Tokyo have built a model to mimic the wing motion and wing shape of the swallowtail, which even includes the thin membranes and veins that cover its wings.

Found on all continents except Antarctica, swallowtails are unique among butterflies because their wing area is very large relative to their body mass. This, combined with their overlapping fore wings, means that their flapping frequency is comparatively low and their general wing motion severely restricted.

As a result, swallowtails’ ability to actively control the aerodynamic force of their wings is limited. Their body motion is a passive reaction to the simple flapping motion, and not – as is common in other types of butterfly – an active reaction to aerodynamics.

Using motion analysis software, the researchers were able to monitor the ornithopter’s aerodynamic performance, showing that flight can be realized with simple flapping motions without feedback control, a model that can be applied to future aerodynamic systems.

This research was published yesterday in the journal Bioinspiration & Biomimetics.

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Decomposing VX nerve agent with ultraviolet laser light (Courtesy: INL)

By Margaret Harris

Here’s one possible laser application that didn’t make it into this month’s special issue: using lasers to remove chemical contaminants after a terrorist attack.

According to a press release from the US Department of Homeland Security, researchers at Idaho National Laboratory (INL) have successfully used ultraviolet-wavelength lasers to remove samples of mustard gas and the nerve agent VX from porous surfaces like concrete. One of the scientists involved, INL chemist Bob Fox, compared the process to “laser steam-cleaning”.

As you might expect, the details in the press release are a little sketchy, but it appears that UV light from the laser is breaking molecular bonds in the VX, causing it to decompose into non-hazardous daughter products – and leaving behind the “harmless” (if rather nasty looking) brown stain shown in the photo.

This isn’t an entirely new idea; instead, it’s an adaptation of older procedures that use lasers to scrub soot off buildings and unwanted tattoos off human flesh. The INL team has also studied ways of using lasers to remove radioactive contamination, and might move on to biological contaminants in the future. “I’m willing to shine my light on anything,” says Fox.

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By Hamish Johnston

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I had a fantastic day out yesterday at the National Physical Laboratory (NPL) on the outskirts of London.

The 20th of May is, of course, “World Metrology Day” and NPL bravely threw open its doors to the public, who could wander freely through many labs and chat to the researchers.

Well that was just heaven for me – lasers, vacuum chambers and enthusiastic physicists around every corner, and all the coffee and biscuits you could manage!

So what did I see? A caesium fountain atomic clock for example (right) – okay, the gubbins are covered, but at least you can see the size of the thing. I got to speak to Witold Chalupczak and Krzysztof Szymaniec, who built the clock and did a great job of explaining how it works.

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When you think of Josephson junctions and metrology, magnetic field measurements probably spring to mind. However, the tiny superconductor-insulator-superconductor junction can also be used in devices for measuring DC and AC voltages. I learned that from Jonathan Williams (right) and Dale Henderson, who are using microwave guides made from 8192 tiny junctions to create voltage standards with quantum accuracy.

Jonathan was just about to leave for London, where he was being interviewed for BBC Radio’s Material World programme, which you can listen to here. Jonathan chips in about 22 minutes into the show.

It wasn’t all condensed-matter physics, by the way. Here’s a health physics question: What type of radiation is the biggest worry for those setting exposure levels for aircrews?

The answer is neutrons. Apparently there are lots of high-energy neutrons whizzing around up there, created by collisions between air molecules and particles from the Sun and the cosmos.

If such a neutron happens to smash into hydrogen or another light nucleus in your body, the nucleus will recoil as a high-energy charged particle that will cause damage to living cells.

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That’s why Graeme Taylor (above left) and Neil Roberts (above right) have developed both hardware and software to work out how neutrons contribute to the overall dose received by aircrews. Between Graeme and Neil you can see their cylindrical detector, which spends much of its time on commercial airliners.

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The scientists had great stories of trying to get their instrument on an airliner to coincide with a solar outburst, only to discover that the plane was in a hangar when the fireworks kicked off.

Graeme and Neil explained why crew flying over the poles tend to get higher doses than those flying over the equator. I also asked them if crews could exceed cumulative exposure guidelines when the sun comes out of its current lull in activity. Apparently it’s possible.

It wasn’t all fun and games for me at NPL. I sat down with several leading scientists to do formal interviews, which we will publish shortly. One interviewee was Michael de Podesta (right), who told me all about an extremely smooth copper sphere that he hopes to fill with sound and use as a temperature standard.

Michael also enthused about how he encourages adults to think about physics in his Protons for Breakfast programme. One of the highlights is the “gherkinator”, where he passes an electrical current through pickled cucumber until it glows. Sadly, I had to leave before Michael’s demonstration.

By Hamish Johnston

As a young lad in the 1970s I remember enjoying Carl Sagan’s television programme Cosmos.

Did it inspire me to become a physicist? Not really, but it was entertaining and there was something very soothing about the way Sagan spoke in an accent best described as “Brooklyn intellectual”.

One physicist (and TV personality) who was inspired by Cosmos is Brian Cox, who was on BBC Radio 4’s Great Lives programme yesterday to sing the praises of Sagan.

“As a young boy of 13, Brian Cox stared at his television screen every Wednesday evening, as Carl Sagan took him on a journey across the Cosmos”, says the BBC’s promotional material.

Sagan, who died in 1996, was somewhat controversial as both a scientist and a promoter of science and the BBC programme asks: “So just how good a scientist was he, and what is his legacy?”

You can listen to the programme here .

By Michael Banks

Physicists have come out on top in Princeton University’s fourth “art of science” competition.

The annual exhibition features images created during scientific research and this year’s event was held on 7 May with the theme of “energy”.

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Xenon Plasma Accelerator (credit: Princeton University Art of Science Competition )

Jerry Ross, a postdoc at the Princeton Plasma Physics Laboratory won first place for his “xenon plasma accelerator” image. The picture (right) is of a so-called “Hall effect thruster” – a type of ion thruster where electrons, held in a magnetic field, are used to ionize a propellant, which is then used to produce a thrust.

Third place also went to a physicist. Tim Koby, a physics undergraduate at Princeton, produced a picture of the interaction of a neutron star with a black hole in the centre of a galaxy.

Koby was beaten into second place by David Nagib, a chemistry graduate at Princeton who produced an image called “therapeutic illumination”.

Ross bagged $250 for winning best exhibit, with $154.51 awarded to Nagib in second place and $95.49 to Koby in third.

And if you are wondering why those last two figures are not rounded to $150 or $100, it is apparently because they are derived according to the golden ratio – equal to 1.6180339887 – that represents, in this case, the ratio of the higher to the lower number.

You can also watch a video of the exhibits here.

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Part of the XENON100 experiment (Courtesy: XENON100 collaboration)

By Hamish Johnston

Is the XENON100 collaboration in the dark about dark matter, or will its critics see the light? The latest installment of this debate has appeared on the arXiv preprint server.

On 6 May Jon Cartwright reported on a furore that has broken out in the dark-matter detection community.

Earlier that week the XENON100 collaboration posted a preprint with an analysis of the first experimental results from its dark-matter detector. It didn’t see any of the dark stuff, which means that the positive sightings reported by two other experiments (DAMA and CoGeNT) could be false.

But then two US-based physicists – Juan Collar and Dan McKinsey — posted a preprint that took XENON100 physicists to task on their analysis of the data. In particular, Collar and McKinsey believe that the XENON100 team is overconfident about how it extrapolated the known response of the detector to high-energy particles to lower energies – where the response is unknown.

This low-energy response is crucial because that is where XENON100, DAMA and CoGeNT have all looked for dark matter.

Now, XENON100 has responded with yet another preprint defending its analysis and claiming that it has “properly taken into account the uncertainty” in the low-energy response.

I can’t wait for the next preprint in this dark-matter “he said, she said”!

Japanese robotics couple married by android

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By James Dacey

We all know colleagues who allow their work to stray a little bit too far into their personal lives.

But a pair of robotics researchers in Japan surely took this to whole new levels when they were married yesterday by a 1.5 m android named I-Fairy.

The bride was 36-year-old Satoko Inoue who works for Kokuro, the firm that produced I-Fairy, one of their new generation of androids.

“This was a lot of fun. I think that the Japanese have a strong sense that robots are our friends,” she told the Associated Press.

Her new husband is Tomohiro Shibata, a 42-year-old professor of robotics at the Nara Institute of Science and Technology, was a bit more critical of their plastic priest. “It would be nice if the robot was a bit more clever, but she is very good at expressing herself,” he said.

The service took place at a rooftop restaurant in central Tokyo and you can enjoy the happy couple exchanging vows in this short YouTube clip.

By Margaret Harris

Fifty years ago today, a little-known scientist working in an underfunded lab in California set off a scientific and technological revolution. On 16 May 1960, Theodore Maiman and his assistant Irnee d’Haenens succeeded in coaxing a beam of coherent light out of a flashlamp-pumped crystal of pink ruby. The laser had arrived.

Of course, the events of that day were not the whole story. Although Maiman is rightly honoured for inventing the first working laser, many others played a role in the laser’s development, both before and (particularly) after the initial breakthrough. Among the key early figures were Einstein, whose predictions about stimulated emission laid the theoretical groundwork; and Charles Townes, who invented the laser’s microwave predecessor, the maser.

To learn more about the early days of the laser, I’d highly recommend downloading Physics World’s May special issue, which you can do for free via this link. On page 23, you’ll find a great article by Pauline Rigby called “And then there was light”, which describes the events leading up to Maiman’s breakthrough and some of the controversy that followed it.

As for what happened next, I think the thing that surprised me most when I was researching the special issue was just how quickly researchers in various fields found ways of putting Maiman’s new toy to use. Barely a year after its invention, a device that d’Haenens memorably called “a solution looking for a problem” was already being used for human eye surgery.

So what will we be doing with it in 2060? Well, as Niels Bohr supposedly said, “Prediction is difficult, especially about the future” — but if you want to hear some experts’ views , check out “Where next for the laser?” on p53 in the downloadable pdf. You can also watch our laser video series .

Update: Pauline Rigby has written an entry on her own blog about how the article “And then there was light” came into being — including additional material from her interview with Maiman’s wife Kathleen. You can read it here

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With a little help from their friends: some of the DØ collaboration

By Hamish Johnston

Many years ago I wanted to be an experimental particle physicist (didn’t you?).

But then I cast my eyes over a few papers and realized that my name would be buried between D Johnston and A Jonckheere in a two-page list of authors (if I was lucky enough to join the DØ collaboration above).

I can’t say that was the only reason that I switched to condensed matter physics – I found it more interesting, for example – but the idea of being a small cog in a huge machine wasn’t that appealing.

Since then I’ve often wondered how hundreds (indeed, thousands) of particle physicists get together to write one paper.

If you are curious, Tommaso Dorigo has a blow-by-blow account on his blog.

Among other things, it involves committees referred to as “godparents” and arguments over British versus American spellings – although I would have thought the journal would have the last word on the latter.

Dorigo writes, “Now, if you think that the above baroque, surreal, ridiculous procedure is crazy, you might be right”.

However, he also points out that the process is “extremely democratic”, which he says is one of its “striking positive qualities”.

But is democracy the best way of doing science?

Cast your ballot now!

Bat–man collaboration

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Rousettus aegyptiacus, a type of fruit bat

By James Dacey

Nope, this is not a scheme by the new British government to keep track of mischievous dogs.

This is one of the Egyptian fruit bats involved in research in England and Scotland to unlock the secrets behind bats’ remarkable ability to “see” in the dark.

It is well known that bats use the echoes from their own calls to recreate the landscape through which they are flying.

This is the same basic principle that underpins sonar technology used by submarines to map out the ocean floor and to detect other vessels.

Bats, however, have a super duper version of sonar which enables them to resolve their surroundings in much finer detail. Their two ears receive the echoes at slightly different times and at different loudness levels, depending on the position of the object generating the echoes, enabling them to perceive distance and direction.

Many bats also have an inbuilt acoustic gain control that allows them to emit high-intensity calls without deafening themselves and then to apply a gain to returning signals.

Simon Whiteley at the University of Strathclyde in Scotland has led a team to create a special sensor to monitor this process, which was then mounted onto the backs of a number of Rousettus aegyptiacus.

The six bats performed up to sixteen flights each along a flight corridor. Each flight was short – lasting only about three seconds – but, with the bats’ clicks only lasting a quarter of a millisecond, a large number of calls were recorded for the scientists to analyse.

Back in the lab, the researchers copied the animals’ functions by recreating the bat chirps and receiving them using a spectral equalization technique.

Their findings are published this week in Bioinspiration and Biomimetics.

Whiteley’s team will continue studying these bats with a view to developing applications such as positioning systems for robots.

By Michael Banks

After a few days of political horse-trading, a resignation speech from former UK prime minister Gordon Brown and the emergence of the first coalition government since the Second World War, the UK has a new science minister.

Last Thursday’s general election resulted in a hung parliament, meaning no party had an overall majority. After days of coalition talks between the three main parties, the Conservatives and the Liberal Democrats joined in a government, with David Cameron as prime minister.

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Cameron spent most of yesterday announcing the members of his new cabinet and late last night it emerged that David Willetts, Conservative Member of Parliament for Havant, will be the minister of state for universities and science in the department for business, innovation and skills.

Nicknamed “two brains”, Willetts was shadow secretary of state for innovation, universities and skills from July 2007 and before that was shadow secretary of state for education from December 2005 to July 2007.

Like his predecessor Paul Drayson, who was science minister in the Labour government under Gordon Brown, Willetts will not be a cabinet minister, but will be attending cabinet meetings.

Willetts, however, takes over the role as science minister at a testing time for science funding in the UK. Following the deficit in the budget of the Science and Technology Facilities Council that resulted in the UK pulling out of 25 international projects in December, Drayson won plaudits for making structural changes to the STFC that will better protect the funding council from foreign currency fluctuations that affect its international subscriptions.

Willetts will now have to deal with the ramifications of the STFC’s changes and its continuing budget deficit as well as any budget cuts that could happen when the new coalition government announces its spending review, which is expected to happen in the autumn.

Previous statements by Willetts when he was shadow secretary of state for innovation, universities and skills indicate that he will fight to maintain the science budget from swingeing cuts. “It is important that science is funded properly. It should not be about the government picking winners; it should be about supporting academically excellent research centres,” Willetts said when the STFC’s budget problems first emerged in December 2007. “We will scrutinize these proposals to make sure they improve things after last year’s scandal when the government took £75 million from science by stealth.”

Willetts has also apparently said that he would like to delay the Research Excellence Framework (REF), which is used to allocate funding to individual universities. The REF replaces the Research Assessment Exercise and will include quantitative information like bibliometric data in addition to the existing peer-review evaluation.

The University and College Union (UCU) released a statement today welcoming the appointment of Willetts as science minister. “Mr Willets proved his ability to listen to staff concerns when committing to delay unpopular plans to make university research funding dependent on economic impact,”; says Sally Hunt, general secretary of the UCU. “The academic community made clear its view that assessing and funding research according to its impact is unworkable and we urge him to put an end to this sorry chapter once and for all.”

Hunt also warned that Willetts will need to “listen to the ever-widening consensus of opinion which opposes cuts in college and university budgets, caps on student numbers, the privatization of academic institutions and increases in the cost of a university education for hard-working families”.

The Campaign for Science and Engineering (CaSE) also welcomed Willetts appointment. “In his former roles as shadow secretary for education and then innovation, universities and skills, David Willetts always engaged with science issues,” says Hilary Leevers, acting director of CaSE. “It is vital that the minister for science works closely with the department for education. As former shadow of this department, Willetts will be well positioned to do this.”

By Hamish Johnston

Ball lightning is a phenomenon in which a fiery sphere floats through the air near the surface of the Earth, usually during a thunderstorm. Or is it?

Although ball lightning is very rare, researchers have collected thousands of eyewitness observations from around the world, and there are even a few photographs of the fiery apparitions. While some researchers have been able to create glowing orbs in the lab, physicists haven’t really been able to explain why they occur in nature.

Well, maybe that’s because ball lightning exists in the brain of the beholder – at least some of the time.

That’s the conclusion of a report recently posted on the arXiv preprint server by Alexander Kendl and Joseph Peer at the University of Innsbruck. They argue that electromagnetic pulses emitted by lightning discharges could lead to the perception of “magnetophosphenes” by persons nearby.

Magnetophosphenes are luminous shapes that are perceived by people undergoing transcranial magnetic stimulation (TMS) – a technique used to stimulate brain activity using magnetic pulses.

Kendl and Peer have calculated that a person up to 100 m away from long-duration (1–2 s) repetitive lightning discharges would receive about the same dose as a TMS subject.

Although they admit that such lightning events are rare, they claim, “Lightning electromagnetic pulse induced transcranial magnetic stimulation of phosphenes in the visual cortex is concluded to be a plausible interpretation of a large class of reports on luminous perceptions during thunderstorms.”

By Matin Durrani

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Regular users of this site will be well aware that we are currently celebrating the 50th anniversary of the invention of the laser.

It was on 16 May 1960 that Theodore Maiman – then a 32-year-old engineer-turned-physicist at Hughes Research Laboratories in the US – eked out the first pulses of light from a pink-ruby crystal, since which the laser has become a workhorse of physics and ingrained in everyday life.

To celebrate the laser anniversary, we’re offering a free PDF download of the May issue of Physics World (right), which you can get by following this link.

Packed with great laser features, we relive the race to build the world’s first working laser – a story still laced with controversy. Find out about the technological impact of lasers in fibre optics and the quest for green-wavelength laser diodes that could let mobile phones project images onto any surface.

Basic research gets a look-in, too – in terms of both ultrahigh power lasers to promote fusion as well as ultrafast lasers that can probe the motions of atoms and molecules. And don’t miss our special, colour-coded timeline of laser history.

And if that’s not enough, don’t forget you can also view a series of great video interviews with leading laser experts via the physicsworld.com multimedia channel.

If I can recommend just one of the videos, it’s the one with Tom Baer, former president of the Optical Society of America, in which he overviews 50 years of laser physics, and makes some predictions about the next 50. Watch it here.

Of course, we’re not the only ones to be marking the laser anniversary. Thanks to the efforts of my colleague Joe Winters at the Institute of Physics press office, today’s edition of the Sun – the UK’s best-selling newspaper – has a great article marking the laser anniversary. Check it out via this link.

But don’t spend too long at the Sun – for the real deal on lasers, you really mustn’t miss the May issue of Physics World.

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By Hamish Johnston

There really is an iPhone app for everything…

Researchers at the University of Utah’s Nuclear Engineering department have used an iPhone visualization application – or app – to display simulations of nuclear reactor cores (see right).

Called ImageVis3D Mobile, the app was first developed by the university’s Scientific Computing and Imaging (SCI) Institute to look at medical CT or MRI scans.

Now it seems that Tatjana Jevremovic and colleagues have come up with a way to use the app to visualize the results of reactor simulation software named AGENT (Arbitrary Geometry Neutron Transport).

Jevremovic’s ultimate goal is to develop a secure way for nuclear engineers in academic settings to share simulation data with those at commercial power plants.

Although the ImageVis3D can be downloaded for free from the Apple App Store, don’t expect to be simulating reactor cores anytime soon – to do that you’ll need access to the university’s computers.

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It’s dusty out there: image taken by NASA’s Wide-field Infrared Survey Explorer

By Hamish Johnston

This morning the BBC’s Melvyn Bragg gathered three of the UK’s top astronomers for a chat about the “cool universe” – the vast amounts of matter between the stars that is invisible to optical telescopes.

This dust and gas is best studied using instruments sensitive to infrared radiation – technology that only really got going in the 1960s and works best in space, away from Earth’s infrared glow.

Bragg was joined by Carolin Crawford of Cambridge University, Paul Murdin of Liverpool John Moores University and Imperial College’s Michael Rowan-Robinson, who explained what these infrared telescopes have revealed.

They described a “dynamic universe” in which gas and dust created by the death of past stars is recycled to create stars – and planets – of the future.

“As a result of the new research, we are now beginning to see first-hand the way our planet was formed when the solar system was born,” says Bragg.

You can listen to the broadcast here.

By Michael Banks

Tomorrow the UK will have a general election and while physicsworld.com does not endorse a particular party, we have put together some of the science-based pledges from the three main parties – Conservative, Labour and Liberal Democrat.

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In March, the campaign for science and engineering in the UK (CASE) wrote to the main parties to ask them to set out their policies for science and engineering in advance of the election. Here are some of the responses as well as what the parties’ manifestos and their science representatives have to say.

So if you are still undecided about who to vote for then maybe the parties’ science policies will help you to decide where to put that cross on the ballot paper tomorrow.

Conservatives led by David Cameron

Response to CASE: “To provide real incentives to get more good science teachers into out school, we will pay off the student loan obligations of top STEM graduates for every year they spend in the classroom.

“We will postpone the Research Excellence Framework by up to two years, while we review the evidence behind the new system.

“I want the next Conservative government to act early, sensitively and intelligently so that scientific research can move forwards within the boundaries set by Parliament.”

What Adam Afriyie, shadow minister for innovation, universities and skills, says: “Our science base is a valuable national asset. Economically, politically and socially, it underpins the prosperity and wellbeing of our nation.”

What the Conservative manifesto says: “Initiating a multi-year science and research budget to provide a stable investment climate for research councils.”

Labour led by Gordon Brown

Response to CASE: “We will continue to support curiosity driven research, which has underpinned the breadth and excellence of UK science over the last ten years. In setting research priorities, we respect the Haldane principle.

“The success of UK science has also been underpinned by a ring-fenced science budget and a ten-year framework.

“Scientific advice should be at the heart of government and society. We have chief scientific advisers in almost all government departments. And for the first time the science minister sits at the cabinet table.”

What Paul Drayson, minister for science and innovation, says: “Science isn’t peripheral to the decision facing the country. It is central: to growth, to prosperity and well-being.”

What the Labour manifesto says: “We are committed to a ring-fenced science budget in the next spending review.”

Liberal Democrats led by Nick Clegg

Response to CASE: “Liberal Democrats would abolish tuition fees over a six year period. We see them as unfair and a regressive tax on education.

“We are committed to not cutting science spending in the first year of a new parliament. We are also committed to not allowing the science budget to be raided once it is fixed for the given Comprehensive Spending Review period.

“Liberal Democrats believe that public policy should be evidence-based as far as possible. Advisers must feel able go give their advice without fear of being bullied if it is not what a minister or tabloid newspaper editor wants to hear.”

What Evan Harris, Liberal Democrats spokesperson for science, says: “We recognize that science, technology, and engineering have to be key drivers of our economy as we move out of recession.”

What the Liberal Democrat manifesto says: “In the current economic climate it is not possible to commit to growth in spending, but Liberal Democrats recognize the importance of science investment to the recovery and to the reshaping of the economy.”

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David Smith (left) is philosophical about metamaterials

By James Dacey

In March, a group of researchers in the UK and Germany grabbed the science headlines when they unveiled the world’s first optical cloak that could hide an object in three dimensions. Okay, the thing they hid may only be a microscale bump but the researchers say their design could in principle be scaled up into a full Harry Potter-style invisibility cloak.

A new paper, however, on the arXiv preprint server has poured cold water on the breakthrough by pointing out a slight flaw in the cloak design – namely that it doesn’t really hide things.

Cloaking requires special materials known as metamaterials, which possess unique optical properties. The trick is to create a material whose optical properties are constantly changing so that it “steers” waves around an object as if it were not there.

This recent breakthrough involves a type of cloak known as a “carpet cloak” because it involves smoothing out a bump on a surface as if flattening out a ruck in a rug. The researchers stacked nanofabricated silicon wafers on top of one another to produce a distribution of refractive indices. As light reflected off the surface, it appeared as if the device (and the bump it was hiding) was not there.

To engineer the carpet cloak, the researchers had to modify a conducting surface to create a grid in which the mechanical and optical properties are uniform in all directions. And this is the point where the technology breaks down – claim a trio of researchers in this arXiv paper.

Bae-Ian Wu and his colleagues at Massachusetts Institute of Technology are concerned that a cloak that is isotropic could never truly hide an object. Instead, it shifts an object to the side by an amount related to the angle of incoming light: change your viewing angle, you still see the object.

To illustrate their point, they trace a ray of light as it approaches a bump of 0.2 units from an angle of 45 degrees. According to the calculations, the ray is shifted laterally by 0.15 units.

The solution, they say, is to create a cloak whose optical properties are anisotropic, i.e. they vary depending on orientation.

I got in touch with John Pendry of Imperial College in London who was involved in the recent cloak design to get his reaction. “We already knew that the isotropic cloak was not exact, the question is by how much,” he said. “The first step [in the research] was the exact specification of the cloak which made objects truly invisible when viewed against a mirror background. However this exact prescription requires anisotropic optical materials and would be very difficult to manufacture.”

I also got in touch David Smith, at Duke University in the US, who is credited with creating the first metamaterial cloak back in 2006. “The carpet cloak is not really a cloak, as we know, but a different example of a transformation optical structure,” he said.

Smith was philosophical, however, about the achievements in metamaterial research so far. “The optics world has lived for 100s of years with imperfect optics! If our goal is not to make something perfect, but make something that is less poor than what exists, our chances of success are much greater. Transformation optics and quasi-conformal techniques help us do just that.”