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Our favourite pictures of 2014

Physics World brings Feynman lecture to life

Commissioned for our March 2014 education special issue, which focused on novel ways to teach and learn physics, the riot of colour above is based on a lecture by Richard Feynman called “The Great Conservation Principles”. It is one of seven Messenger Lectures that Feynman gave at Cornell University in the US half a century ago. This lovely image was created by professional “science doodler” Perrin Ireland – a science-communications specialist at the Natural Resources Defense Council in the US – who describes herself as “a learner who needs to visualize concepts in order to understand them”.

Scientists crack oyster’s secret of strength

Micrograph showing localized damage in an oyster shell — Shatter-proof shell: this colourized scanning electron micrograph shows four localized damage sites on an oyster shell. (Courtesy: Ling Li and James C Weaver)

The pink and green hues in this colourized, scanning electron micrograph show localized damage on the shell of a windowpane oyster (Placuna placenta). The image was taken by researchers at the Massachusetts Institute of Technology, who uncovered a series of nanoscale mechanisms that make such transparent oyster shells resistant to the piercing teeth of predators. Living in waters off the Philippines and other parts of the tropical central Indo-Pacific region, the windowpane oyster’s shell might be the toughest see-through material in nature, with studies revealing that the shell’s toughness is down to how its very thin calcite layers respond to being hit.

Rise of the real transformers

While the latest Transformers film hit cinemas in the UK in August this year, scientists at Harvard University and the Massachusetts Institute of Technology in the US were busy developing the first “real life” transformer, pictured above. Starting out flat, the robot folds and assembles itself into a complex shape and can then scuttle away – all without any human intervention. These printed robots can self-fold in about four minutes – a huge improvement on previous models that could take up to two hours to do the same thing – and can even turn around, making them a handy tool.

NASA’s Stardust mission snares first dust from beyond the solar system

False colour image of the diffraction pattern of the dust grain Orion — From the beyond? False-colour image of diffraction pattern from one of the dust grains called Orion. (Courtesy: Zack Gainsforth)

Seven rare, microscopic dust particles, which could be of interstellar origin, have been found among samples collected by NASA’s Stardust mission. Above is a false-colour image of a diffraction pattern from one of the dust grains, dubbed Orion. The tiny particles show features that are consistent with dust that would be found in an interstellar dust stream, suggesting that they date back to the beginnings of the solar system. If confirmed to be of interstellar origin, the discovery could improve our understanding of the origin and evolution of the solar system itself.

“Angry alien spider” emerges from packing calculations

A packing density surface that resembles an angry alien spider — Angry alien spider: a continuous family of polyhedrons with tetrahedral symmetry is shown in the bottom half of the figure, with the corresponding maximum packing density surface shown in the upper half. (Courtesy: Elizabeth Chen)

Determining the most efficient way to pack simple objects such as spheres has entertained and infuriated mathematicians from Aristotle to the present day. Earlier this year, researchers at the University of Michigan in the US took a new computational approach to the problem, by studying how packing efficiency varies as the shape of an object is modified. They looked at how the maximum packing efficiency of tetrahedrons and several other simple polyhedrons varies according to two parameters. So, the alien spider that seems to be guarding its colourful bounty of eggs in the image above is nothing to worry about. In fact, it illustrates a plot of maximum packing efficiency as a function of the two parameters for one selected family of polyhedrons with tetrahedral symmetry. The polyhedrons are shown below the main image, while the corresponding maximum packing density surface is shown in a 3D plot.

SPHERE opens its “all-seeing” eye

Ringing the changes

While the fiery shades of the image above may seem familiar to fans of the Lord of the Rings movie franchise, pictured above in exquisite clarity is a ring of dust that surrounds the nearby star HR 4796A. This particularly clear image has been obtained by the new Spectro-Polarimetric High-contrast Exoplanet REsearch instrument (SPHERE), which was installed in May this year on the European Southern Observatory’s Very Large Telescope (VLT) at the Paranal Observatory in Chile. Thanks to SPHERE, not only is the dust ring clearly outlined, but the glare of the bright star at the centre of the picture has been supressed. This has provided a much clearer view of the whole system, which researchers think also harbours an exoplanet or two.

Lasers ignite “supernovae” in the lab

An image of the lab-based supernova created using the lasers — Shocking front: laser beams illuminate a small carbon rod and launch an asymmetric shock inside a chamber filled with argon gas. The shock and the turbulent flow are captured with the Schlieren imaging technique (blue-black hues). The electron density predicted by computer simulations (blue-red hues) is superimposed. (Courtesy: Oxford University/University of Chicago)

Attempting to recreate one of the most massive explosions in the universe in your lab may not sound like such a good idea. But that is exactly what researchers at the University of Oxford in the UK wanted to do, as they used one of the world’s most powerful laser facilities to create tiny versions of supernova explosions in the laboratory. The simulated “bang” was created by firing three laser beams onto a tiny carbon rod in an argon-filled chamber. The exploding rod creates an asymmetric shock wave that expands outwards through the argon gas, much like a real supernova in space. In the image above, the shock and the turbulent flow are captured with the Schlieren imaging technique (blue-black hues). The electron density predicted by computer simulations (blue-red hues) is superimposed.

First view from the comet crasher

A black-and-white image of the comet 67P/Churyumov-Gerasimenko — Rosetta’s lander Philae is safely on the surface of Comet 67P/Churyumov–Gerasimenko. One of the lander’s three feet can be seen in the foreground. (Courtesy: ESA/Rosetta/Philae/CIVA)

Earlier this month, scientists working on the Rosetta mission of the European Space Agency (ESA) made history when their “Philae” module touched down safely on the surface of comet 67P/Churyumov–Gerasimenko. The lander bounced twice, moving nearly 1 km back out into space, and touched the comet’s surface three times before settling at a location nearly 1 km away from the target site. Above is the first panoramic image from the surface of the comet captured by the CIVA-P imaging system, and features a 360° view around the point of final touchdown. One of the lander’s three feet can be seen in the foreground.

Planck offers sharpest view of the early universe

Image of the sky as seen by Planck — The sky in terms of the polarization of 35 GHz radiation detected by Planck. The colours show galactic dust, while the relief depicts magnetic fields. (Courtesy: ESA-Planck Collaboration, highlighted by Marc-Antoine Miville-Deschenes)

The beautiful image above, which is reminiscent of an Impressionist painting, comes from the latest data from the €700m Planck mission of the European Space Agency (ESA), which was released last month. It shows the 353 GHz polarization sky map as seen by Planck, with the colours depicting galactic dust, while the relief shows magnetic fields. These results cover four years of observations and provide the most precise confirmation so far of the Standard Model of cosmology, as well as placing new constraints on the properties of potential dark-matter candidates. The collaboration also revealed that it has detected traces left behind by primordial neutrinos – thought to have been released one second after the Big Bang – on the cosmic microwave background for the first time.

Hawking in the movies

Eddie Redmayne as Stephen Hawking in the film The Theory of Everything — Action! Eddie Redmayne as Stephen Hawking in the film *The Theory of Everything*. (Courtesy: Universal Pictures International)

Early next month, director James Marsh’s biopic based on Stephen Hawking will hit cinemas across the UK. Above is a still from the film, The Theory of Everything. The story is based on the memoir Travelling to Infinity: My Life with Stephen, penned by Hawking’s former wife Jane Hawking, and covers the early days of the couple’s courtship up to the point where the two divorced in 1995. Hawking is played by British actor Eddie Redmayne, who has already received praise for his performance as he portrays Hawking slowly deteriorating because of motor-neuron disease – amyotrophic lateral sclerosis – that he is diagnosed with at an early age.

The 10 quirkiest physics stories of 2014

From a particle collider made of LEGO to physicists taking on the ice-bucket challenge, physics has had its fair share of interesting stories this year. Here is our pick of the 10 best, in chronological order.

The designated survivor

The nuclear physicist and US energy secretary Ernest Moniz may be 14th in the US presidential line of succession, but if something really terrible had happened in late January, then he might have found himself leading the world’s biggest economy. That is because Moniz was appointed the “designated survivor” while US president Barack Obama delivered his State of the Union address earlier this year.

The speech, which is attended by the country’s top leaders, including the vice-president, members of the US cabinet and Supreme Court justices, is where US presidents outline their legislative agenda for the coming year. A designated survivor is a member of the cabinet who stays at a distant, secure and undisclosed location during the address to maintain continuity of government in the event of a natural disaster or terrorist attack that ends up killing officials in the presidential line of succession.

Of course, nothing untoward happened, so Moniz did not find himself as leader of the world’s richest nation. The question remains, however, where was Moniz during the speech? Having emerged with his trademark flowing grey hair intact, at least we know Moniz wasn’t at the hairdressers.

Spin-glass: the game

Alexander Hartmann is determined to make condensed-matter physics fun. The University of Oldenburg physicist has created a board game for two players dubbed “Spinglas”, in which each player has either white or black counters (representing spin up or down) and then takes turns to place three pieces on the board. (Full instructions on how to make Spinglas are on the arXiv preprint server).

Pieces played can be either these counters or wooden links representing “interactions” between spins – blue being ferromagnetic and red antiferromagnetic. If a player’s move results in the majority of interactions around the spin being “satisfied” – like ferromagnetic bonds between two similar spin orientations – then the energy is negative, but if more are unsatisfied, like an antiferromagnetic interaction between two up spins, then the net energy is positive.

A total positive energy near the spin means that a player can also “flip” the spin to result in a lower energy. The winner is whoever has more counters of their colour on the board at the end of the game. “People who have played the game say that it is a real challenge,” Hartmann told physicsworld.com, adding that high schools and universities are using it to teach students. It might be the best €16 you ever spend. Possibly.

Tied in knots

The Eldredge tie. (Courtesy: Mikael Vejdemo-Johansson)

If you have ever pondered how many ways there are to tie a necktie then wonder no more. Mikael Vejdemo-Johansson, a mathematician at the KTH Royal Institute of Technology in Stockholm, and colleagues have come up with a mind boggling 177,147 variations.

The inspiration for the work apparently came from the fiendishly complex knot sported by the “Merovingian” villain from the Matrix films. The number Vejdemo-Johansson and pals came up with is a vast increase on the 85 ways that physicists Thomas Fink and Yong Mao from the Cavendish Laboratory in Cambridge found in 2000. According to Vejdemo-Johansson, their number is much larger because Fink and Mao made various assumptions about tie knots that drastically reduced the number available, including that tie-wearers would only make a “tuck” – pushing the tie into the knot to lock it in place – at the end of a given tying sequence.

So what is his favourite from the 177,147 variations? “I waver back and forth between the Eldredge, the Trinity and the Allwin depending on my mood and the current tie,” Vejdemo-Johansson revealed to physicsworld.com.

Rock, paper, scissors

What is the best strategy to beat an opponent at rock-paper-scissors? The answer, according to three physicists in China, is apparently not to have one. Zhijian Wang from Zhejiang University and Bin Xu from Zhejiang Gongshang University teamed up with Hai-Jun Zhou from the Institute of Theoretical Physics in Beijing to recruit 360 students to play the game. The students were divided into 60 groups of six players with each group playing 300 rounds of the game while their actions were recorded.

On average, the physicists found that the players initially chose each action about a third of the time, which is what you would expect if their choices were random. However, on closer inspection, the players’ strategy was seen to consist of predictable patterns so that the players who won the first round tended to stick with the same action, while those who lost would usually switch actions so that rock changes to paper, paper to scissors and scissors to rock. Zhou told physicsworld.com that they are now looking for such hidden patterns in other games, but would not reveal which.

Rolling back the years

Feynman's van — Restoring Richard Feynman’s old van. (Courtesy: Seamus Blackley)

You might not know this, but the Nobel-prize-winning physicist Richard Feynman once painted his Dodge Tradesman Maxivan with Feynman diagrams – pictorial representations that he invented to describe particle interactions. Feynman and his family used to take the van on camping holidays in the US, Canada and Mexico, but once it had seen better days, Feynman’s close friend – the film producer Ralph Leighton – bought the van and put it in storage.

There it remained until 2012 when computer-games designer Seamus Blackley got his hands on the rust-infested motor and sought to bring it back to its former glory. Blackley, who originally studied for a PhD in physics at Tufts University and Fermilab, is an avid restorer of classic Italian cars. “It was a sense of duty, or some kind of possibly dubious feeling regarding a higher calling or some such,” Blackley told physicsworld.com.

Blackley has already retouched the Feynman diagrams, but there is still more work to do, and he hopes that one day the van will go on show at the Smithsonian Museum in Washington, DC. Blackley is also thinking about renovating historical high-energy physics lab equipment. “Anything that one can do to inspire young people to think about fundamental science is our duty to do, right?”

Pets in space

Celestis, the firm behind sending the remains of loved ones into space, has branched out into animals. Celestis Pets now lets you send 1 g of the cremated remains of your cherished dog or cat – or a lock of its hair – into the cosmos.

The cheapest package is “Earth Rise”, which sets you back $995 and involves the remains being blasted into the atmosphere and then returning safely to Earth. For $4995, “Earth Orbit” lets your pet orbit Earth before “harmlessly vaporizing” in the atmosphere upon re-entry. But for those really wanting to go that extra mile, $12,500 sends your domesticated friend to the Moon or even into interstellar space through the “Voyager” bundle.

“The service provides your beloved pet with an incredible journey through the stars, allowing them to explore places they could have only dreamed of in life,” says the firm on its website. And what do you get in return? A certificate confirming that your pet did indeed go into space. Well worth the cash then.

Hawking takes the ice-bucket challenge

The ice-bucket challenge, which involves people pouring a tub of ice-cold water over their heads and posting a video of the dousing online, took the social-media world by storm this year, raising millions of pounds for motor neurone disease awareness and other charities. One of those to get involved is the Cambridge physicist Stephen Hawking, who has suffered with the disease since he was 21.

In a video filmed outside his family home in Cambridge, UK, however, Hawking said it would “not be wise” to be covered with ice after suffering from a bout of pneumonia last year and so let his children – Robert, Lucy and Tim – get soaked instead at his expense.

But ice was clearly not enough for Muhammad Qureshi, an undergraduate from the University of Toronto, who instead poured liquid nitrogen over his head while wearing just a T-shirt and shorts. “Do not try this at home,” Qureshi warned quite rightly on his video, before doing the deed and then frantically trying to prevent the nitrogen from getting in his hair and under his clothes. “It was well planned and executed and didn’t hurt,” Qureshi told physicsworld.com. “But it did feel very unusual.” We’ll take his word for it.

Why Spaniards aren’t lazy

We don’t want to resort to national stereotypes, but there is a view that the Spanish are, well, a bit lazy. In fact, a Spanish parliamentary commission last year advised that Spain should turn its clocks back by an hour from Central European Time to Greenwich Mean Time (GMT) to improve “productivity, absenteeism, stress, accidents and school drop-out rates”.

So when José María Martín Olalla – a condensed-matter physicist at the University of Seville – examined official statistical data from Spain, Italy and the UK, it perhaps came as no surprise to find that Spaniards do indeed wake up, eat breakfast and go to work later. But when Martín Olalla converted the data into “local solar time” – thereby taking both latitude and longitude into account – he discovered that the Spaniards’ daily timetables match those of the Italians or British, being essentially related to the level of sunlight.

Or, as he concludes: the Spanish aren’t lazy, but merely “keeping pace with [their] geographical position”.

Fusion in Chelsea

Fans of the UK reality-TV programme Made in Chelsea, which follows the lives of affluent young people in London, are familiar with those characters dealing with whatever life throws at them. But few would have guessed that one former star of the show would move into physics. Entrepreneur Richard Dinan, who starred in three series of the show, has founded the firm Applied Fusion Systems, which aims to build a prototype fusion reactor.The 28 year old, who doesn’t have a university degree, has been teaching himself tokamak design for over a year and has now employed a team of scientists to “explore the technology” of fusion reactors. Indeed, Dinan is not averse to trying out new ventures, having created a 3D printing business – Ion Core – that he will use to produce some of the tokamak’s components.

The venture has apparently already attracted interest from private investors, with Dinan adding that details about the funding arrangements as well as the project’s members will be released early next year. “I am completely fascinated and convinced in the eventual success of this technology,” Dinan told physicsworld.com. “I feel strongly that it is time private companies started to take this technology very seriously.” Move over ITER.

The LEGO Brick Collider

Avid readers may remember a 560-piece LEGO model of CERN’s ATLAS detector that was created by particle-physicist Sascha Mehlhase from the Niels Bohr Institute in Copenhagen. Not to be outdone, LEGO fan Jason Allemann has now created a LEGO particle accelerator. Dubbed the LEGO Brick Collider (LBC), the design has been submitted to the LEGO Ideas website, which lets fans share blueprints of their own creations.

The 170-piece LBC features a circular track that accelerates a LEGO football to a speed of just over 12.5 km/hr by passing it in-between two horizontal spinning wheels that “kick” out the balls. Allemann, who told physicsworld.com that he could tweak his design to include a detector, says it would be “pretty awesome” if CERN endorsed the project. He is now looking for 10,000 supporters for his design before LEGO will conduct a review of it and, if successful, approve the design for release.

Still, if it doesn’t work out, there’s always a LEGO version of The Big Bang Theory set. It will feature Minifigures of all the main characters as well as the front room set of Leonard and Sheldon’s flat, although the final design, pricing and release date are still being worked out.

You can be sure of more quirky stories from the world of physics next year. See you in 2015!

Physics World’s 2014 Book of the Year honours materials that matter

Cover of the book Stuff Matters — A love letter to materials: the 2014 Book of the Year is *Stuff Matters* by Mark Miodownik.

In the world of popular-science books and TV documentaries, physics is often presented as a really esoteric subject, one that mostly concerns itself with tiny things such as atoms and molecules or really big things such as stars and galaxies. This, however, is only part of the story. In reality, there is a lot of physics going on somewhere in the messy middle, scattered among the ordinary objects we encounter as we go about our daily life. From the buildings we live in to the screen you are reading this on, you will find physics principles at work pretty much everywhere you look – often hiding in plain sight.

In his book Stuff Matters, author and materials engineer Mark Miodownik turns a bright spotlight on the hidden physics and chemistry of everyday materials. Weaving together science and storytelling, he shows readers that these materials are both fascinating in their own right and an essential part of what defines us as human beings – ingenious, tool-using creatures who, for good or ill, have the power to modify our environment to suit our needs. For this, and for bringing a bit of sparkle to a field that has too often been overlooked in popular-science writing, Stuff Matters is Physics World‘s 2014 “Book of the Year”.

Miodownik’s book beat several other strong candidates on Physics World‘s shortlist of 10. To be eligible for this shortlist, a book first had to be selected for review in the magazine in 2014 – a fairly high hurdle, as there are always many more good books published than we have space to review. It also had to win the approval of the external expert or staff member who reviewed it. Members of the magazine’s editorial team then winnowed this list of standouts down to 10 books that we considered particularly well written, scientifically interesting and novel – the three criteria we have stuck with since 2009, when Graham Farmelo’s biography of Paul Dirac, The Strangest Man, became our first “book of the year”.

Although Stuff Matters grabbed the top spot for 2014, we think all of the books on this year’s shortlist are well worth reading. You can hear more about a few of them – and also listen to Miodownik talk about his award-winning book – in our latest podcast, in which Physics World‘s editor Matin Durrani and reviews editor Margaret Harris discuss some of their favourites with host James Dacey.

So, congratulations to Miodownik and all the other shortlisted authors. If you want to keep up to date with physics books in 2015, be sure to keep an eye on the reviews section of this website. In the meantime, we hope some of you will follow our advice in the podcast, and head straight for your favourite bookstore or website to stock up on some of the best physics writing from 2014.

Book of the Year 2014

In this podcast, Physics World‘s editor, Matin Durrani, and reviews editor, Margaret Harris, share their thoughts about the year’s shortlist with host James Dacey. You’ll hear them describe how the shortlist was chosen, and then discuss four of the books on it in more detail before they announce the winner.

The books on the shortlist cover a wide range of topics, from acoustic physics and astronomy to quantum theory and volcanology, and they all meet the criteria of being well written, scientifically interesting and novel. We hope you enjoy hearing about these books as much as the panel enjoyed reading and talking about them, and congratulations again to all the shortlisted authors.

2014 Books of the Year shortlist (alphabetical by author)

Wizards, Aliens & Starships: Physics and Math in Fantasy and Science Fiction Charles Adler

Serving the Reich: the Struggle for the Soul of Physics Under Hitler Philip Ball

Five Billion Years of Solitude: the Search for Life Among the Stars Lee Billings

Plutopia: Nuclear Families, Atomic Cities, and the Great Soviet and American Plutonium Disasters Kate Brown

Smashing Physics: Inside the World’s Biggest Experiment Jon Butterworth

Sonic Wonderland: a Scientific Odyssey of Sound Trevor Cox

The Perfect Theory: a Century of Geniuses and the Battle Over General Relativity Pedro G Ferreira

Stuff Matters: the Strange Stories of the Marvellous Materials that Shape Our Man-made World Mark Miodownik

Einstein and the Quantum: the Quest of the Valiant Swabian A Douglas Stone

Island on Fire: the Extraordinary Story of Laki, the Volcano that Turned Eighteenth-century Europe Dark Alexandra Witze and Jeff Kanipe

Multimedia highlights of 2014

The journey of innovation

From the fun to the far more serious with our next choice. “A better way to detect landmines” is a short film that we made about how physics-based techniques can help to clear mines faster and more efficiently. It features Bill Lionheart, a mathematician at the University of Manchester in the UK, who has been working with colleagues to develop ways to reduce the number of false-positives when searching for mines. One approach taken by Lionheart and his colleagues is to develop the technology and the underlying maths of metal detectors. They are designing devices that can not only detect, but also characterize metal objects in the ground. This makes it possible to disregard the signals that relate to harmless bits of scrap metal, which would otherwise have been treated as dangerous. Lionheart’s work is supported by the charity Find a Better Way, founded by Sir Bobby Charlton, the former England and Manchester United footballer. In the film, interviews with Charlton and Lionheart are combined with photography from conflict zones to illustrate powerfully how even niche areas of physics and maths can have important and unexpected applications across the globe.

We need to talk about quantum mechanics

Illustration of a person lecturing to a crowd — Spread the word: getting to grips with how to interestingly and accurately “talk quantum” to a global audience. (Courtesy: iStockphoto/CamiloTorres)

Finally, the end of the calendar year can bring the opportunity to reflect on the way that you are doing things in your professional lives, and we at Physics World are no exception to this. In November, Physics World reporter Tushna Commissariat presented “We need to talk about quantum mechanics”, a podcast about her experiences at a “quantum boot camp” for people involved in the communication of quantum research. The intensive crash course – held in Sweden – brought together a host of scientists and journalists from across the world to discuss the possibilities and pitfalls of communicating the ideas of quantum mechanics to a global audience. In the podcast, Tushna interviews a number of her fellow “bootcampers”, including the conference organizer, who is the blogger and physicist Sabine Hossenfelder.

So, that wraps up another year on the Physics World multimedia front. Join us in 2015, when one of our key focal points will be the International Year of Light and Light-based Technologies (IYL 2015). This celebration of light and its uses will provide a great opportunity for us to provide more colourful multimedia next year. Join us then.

Comet landing named Physics World 2014 Breakthrough of the Year

History was made at 15:35 GMT on 12 November 2014 when the Philae module touched down on the surface of 67P/Churyumov–Gerasimenko, a comet 511 million km from Earth and hurtling towards the inner solar system at nearly 55,000 km/h. The module bounced twice before coming to rest, and then began collecting data, which has now been sent back to Rosetta scientists for analysis. The landing followed a seven-hour journey for Philae after it separated from the main Rosetta spacecraft. Launched in 2004, Rosetta itself reached the comet after completing a journey of 6.4 billion km that involved three gravity-assisted fly-bys of Earth and one of Mars (see “Rosetta scientists land probe on comet for first time”).

By landing the Philae probe on a distant comet, the Rosetta team has begun a new chapter in our understanding of how the solar system formed and evolved – and ultimately how life was able to emerge on Earth. As well as looking forward to the fascinating science that will be forthcoming from Rosetta scientists, we also acknowledge the technological tour de force of chasing a comet for 10 years and then placing an advanced laboratory on its surface.

The mission was not without its problems. Despite landing in an awkward position where its solar panels do not currently receive enough sunlight to power its instruments, Philae managed to complete all of its planned measurements on battery power alone. The lander was also not able to secure itself to the comet surface as planned, however it did manage to drill into the surface and acquire a sample for analysis.

Organic molecules and dust-covered ice

Preliminary analysis of data sent back from Philae’s Cosac instrument suggests that there are carbon-based organic molecules on the comet. This could prove to be very important information for scientists studying conditions on the very young Earth, which is believed to have been regularly bombarded by comets. The lander’s Mupus instrument was also able to hammer at the comet’s surface, which we now know is covered by a layer of dust about 10–20 cm thick on top of an unexpectedly hard material thought to be water ice.

The instruments aboard the main Rosetta spacecraft have also made important contributions to our understanding of the solar system. Indeed, only this week, scientists using the ROSINA mass spectrometer discovered that the ratio of deuterium to hydrogen in the comet is much greater than that found on Earth (see “Asteroids, not comets, gave Earth most of its water”). This adds strength to the growing body of evidence that the water on Earth was delivered not by comets, as previously thought, but by asteroids.

At 14:00 GMT today, Rosetta mission manager Fred Jansen joined physicsworld.com editor Hamish Johnston in a Google Hangout (see video above) to accept the award and share his unique insights into the mission and the science that it is undertaking. In the video below, Hamish Johnston and colleague Tushna Commissariat explain why Rosetta was chosen as this year’s winner.

The top-10 breakthroughs were chosen by a panel of six Physics World editors and reporters, and the criteria for judging the top 10 included

fundamental importance of research;
significant advance in knowledge;
strong connection between theory and experiment; and
general interest to all physicists.

Now for our nine runners-up breakthroughs, which are listed below in no particular order.

Quasar shines a bright light on cosmic web

To Sebastiano Cantalupo, Piero Madau and Xavier Prochaska of the University of California Santa Cruz in the US, and Fabrizio Arrigoni-Battaia and Joseph Hennawi of the Max-Planck-Institut für Astronomie in Heidelberg, Germany, for using the radiation given off by a quasar to catch the first glimpse of a filament of the cosmic web.

Matter in the universe is not uniformly distributed and exists in a web of filamentary structures with intervening voids. This web is thought to have formed about 380,000 years after the Big Bang and its presence is a widely accepted theoretical prediction. While we can see matter where it has agglomerated into dense objects such as galaxies, astronomers had not seen the whispy filaments of cold gas. Now, Cantalupo and colleagues have spotted radiation emitted by this gas when it absorbs ultraviolet light emitted by a quasar. The research already suggests that the filament is more “lumpy” than expected, and future measurements using other quasars promise to give much more information about the early universe.

Neutrinos spotted from Sun’s main nuclear reaction

Photograph of the Borexino detector — Solace for solar physicists: the Borexino detector in 2007, when it was filled with ultrapure water. The photograph shows the thin nylon spherical “inner vessel” (8.5 m diameter) that is surrounded by a second nylon vessel and about 2000 photomultiplier tubes. The water was later replaced by the organic liquid scintillator. (Courtesy: Borexino Collaboration)

To the Borexino collaboration, for being the first to detect neutrinos from the main nuclear reaction that powers the Sun.

Nearly all of the energy generated in the Sun involves a chain of nuclear reactions that begins with two protons fusing together to form deuterium along with a positron and a low-energy neutrino. Calculations predict that about 60 billion of these neutrinos pass through a square centimetre on Earth every second, but low-energy neutrinos are particularly difficult to detect and so the theory could not be verified. Now, deep under the Gran Sasso mountain in Italy, some of these neutrinos have been detected by spying the flashes of light that occur when the neutrinos collide with electrons in a giant tank of liquid. The Borexino team was not actually expecting to see these neutrinos, but its detector was so well built that the researchers managed to measure a flux of 66±7 billion neutrinos per square centimetre, confirming the long-established theory of solar fusion.

Laser fusion passes milestone

Photograph of the fusion fuel capsule at the National Ignition Facility — Fuel capsule as seen through a cutaway of the hohlraum wall. (Courtesy: Eddie Dewald, LLNL)

To Omar Hurricane and colleagues at the National Ignition Facility (NIF) of the Lawrence Livermore National Laboratory and the Los Alamos National Laboratory in the US, for being the first to obtain a “fuel gain” of greater than one in a laser-driven nuclear-fusion experiment.

Nuclear fusion promises to deliver vast quantities of clean energy, but physicists working on various experiments have made very slow progress towards this goal. Now, Hurricane and colleagues have used NIF’s ultra-powerful laser to crush tiny pellets of deuterium–tritium fuel to produce more energy from fusion reactions than was deposited in the fuel. This comes after a five-year struggle to boost the amount of fusion energy given off in the process. The team focused on achieving a stable compression of the pellets, and on one occasion was able to achieve more than 2.5 times fusion energy out than laser energy in. Much of this energy is in the form of “alpha-particle heating”, which is essential to achieve “ignition”, whereby energy released from fusion causes more fuel to fuse. Although still far from the long-sought-after goal of ignition, the latest results are an important step towards fusion energy.

Electrons’ magnetic interactions isolated at long last

To Shlomi Kotler, Nitzan Akerman, Nir Navon, Yinnon Glickman and Roee Ozeri of the Weizmann Institute of Science in Israel, for being the first to measure the extremely weak magnetic interaction between two single electrons.

Since the 1920s, physicists have known that the electron possesses an intrinsic spin angular momentum and associated magnetic moment. Although researchers have measured the magnetic field of an individual electron, the magnetic interactions between two electrons have proved much more difficult to observe. Magnetic interactions are at their strongest when two electrons are separated by atomic-scale distances, but cannot be measured because other forces dominate the scene. While these other effects weaken as the electrons move further apart, so does the magnetic interaction, which is then lost in noise. Kotler and colleagues overcame these problems by putting two electrons in a long-lasting entangled state, which guarantees a low-noise environment. They were then able to measure the force between the electrons by using a laser to determine whether the electron spins were parallel or antiparallel.

Disorder sharpens optical-fibre images

Simulation of an image carried by the disordered optical fibre — “Anderson localization” in action: simulation of an image carried by the disordered optical fibre created by Arash Mafi and colleagues (top) and a conventional fibre used for endoscopy. The letters are approximately 25 μm wide. (Courtesy: Salman Karbasi)

To Arash Mafi and colleagues at the University of New Mexico, University of Wisconsin-Milwaukee, Corning Inc. and Clemson University, all in the US, for using the phenomenon of “Anderson localization” to create a better optical fibre for transmitting images.

Disorder in an optical fibre usually blurs transmitted images, but Mafi and colleagues have shown that by putting the right kind of disorder in the right place, the ability of a fibre to transmit sharp images can be enhanced. Indeed, their prototype produced a sharper image than the best available commercial imaging fibres. The technique involves using Anderson localization, whereby light will not propagate through a medium with a certain degree of disorder. The team created a fibre made of 80,000 strands of two different materials that are positioned randomly next to each other. The result is disorder in the directions transverse to the length of the strand and order in the direction that the light propagates.

Data stored in magnetic holograms

To Alexander Khitun and Frederick Gertz at the University of California Riverside in the US, and A Kozhevnikov and Y Filimonov of the Kotel’nikov Institute of Radioengineering and Electronics in Russia, for creating a new type of holographic memory device based on the interference of spin waves.

Holography involves reflecting a beam of light from a 3D object and recording the interference pattern that occurs when it is mixed with an identical beam that did not strike the object. It has the potential to store and retrieve large amounts of information in a very efficient way, but the storage density is limited by the wavelength of the light. The spin waves used in Khitun and colleagues’ magnetic holography device have much shorter wavelengths than visible light, and could therefore be used to store data at higher densities. The prototype device comprises two tiny magnets connected by magnetic wires. Data are saved by sending large-amplitude spin waves through the wires to flip the orientations of the magnets. Data are read by sending smaller-amplitude waves through the device and measuring how they interact with the magnets.

Lasers ignite ‘supernovae’ in the lab

To Gianluca Gregori and Jena Meinecke of the University of Oxford in the UK and an international team, for using one of the world’s most powerful laser facilities to create tiny versions of supernova explosions in the laboratory.

Supernovae are massive stellar explosions that leave behind hot, dense clouds of dust and gas that are often beautiful in appearance. One particular remnant, Cassiopeia A, has long puzzled astronomers because of its irregular knotty structure that suggests the presence of very strong magnetic fields. This supernova was simulated by Gregori, Meinecke and colleagues, who fired three laser beams onto a tiny carbon rod in an argon-filled chamber. The exploding rod creates an asymmetric shock wave that expands outwards through the argon gas, much like a real supernova in space. A plastic grid, which simulated a “lumpy” distribution of gas in the region of the supernova, was placed in the path of the shock wave, and the result was strong magnetic fields similar to those observed in Cassiopeia A. The technique could also be used to simulate a range of astrophysical processes, say the researchers.

Quantum data are compressed for the first time

To Aephraim Steinberg and colleagues at the University of Toronto, Canada, for being the first to demonstrate a quantum analogue of data compression in the lab.

Conventional data-compression schemes cannot be applied to quantum information because they involve measuring the values of the data bits to be compressed – a process that destroys quantum information. In 2010, however, physicists in the Czech Republic worked out that a string of identically prepared quantum bits could be compressed, albeit not as tightly as conventional data. Now, Steinberg and colleagues have done this in the lab, and have squeezed the quantum information carried by three photon-based quantum bits into two. The technique could pave the way for a more effective use of quantum memories – which are not easy to create – and offers a new method of testing quantum logic devices.

Physicists sound-out acoustic tractor beam

Simulation of the pressure field surrounding a triangular target in an acoustic tractor beam — Pulling power: diagram showing the two ultrasound beam wavefronts emerging from the bottom corners of the figure and reflecting from the triangular target. The reflected beams both travel in the upward direction. When beams with the appropriate properties are used, there is a net downward force. (Courtesy: *Physical Review Letters*)

To Christine Démoré and Mike MacDonald of the University of Dundee in the UK, Patrick Dahl and Gabriel Spalding of Illinois Wesleyan University in the US, and colleagues, for creating the first acoustic “tractor beam” that can pull an object by firing sound waves at it.

A staple of science fiction, a tractor beam seems to defy physics by pulling an object towards the source of an outgoing beam that carries momentum. The acoustic tractor beam built by Démoré, Dahl and colleagues involves firing two beams of ultrasonic waves at an object. The beams have circular wave fronts that curve around the direction of propagation and so carry angular momentum. When the wave front strikes the target, the angular momentum is redirected as regular momentum. Some of this momentum will be redirected in directions such that the result is a net inward force on the object, pulling it towards the source. The ultrasonic beams were created using a commercial array of ultrasound sources, and the technique could have a range of applications in medicine. These include manipulating objects, fluids and tissue inside the body, and delivering encapsulated drugs to the exact location in the body that requires treatment.

European Science Foundation survives elimination vote

Members of the European Science Foundation (ESF) have voted to keep the 40-year-old research organization alive, but with a very different and much-reduced scope. The vote, which took place during the ESF’s annual general assembly at the end of November, confirms that the foundation will no longer fund pan-European research collaborations, but instead will provide services such as peer review.

Set up in 1974 and based in Strasbourg, France, the ESF currently has 66 member organizations – including funding agencies, research institutions and learned societies – from 29 countries. However, many of the national research councils that provide the organization’s funding view the ESF as too expensive, overly complex and unable to compete with an increasingly powerful European Commission. In 2011 they set up a new organization – Science Europe – to promote their interests in Brussels, and at the same time began to wind down many of the ESF’s traditional activities.

Expanded membership

The recent vote saw 51 members in favour and three against a motion to change the ESF’s statutes to allow new kinds of members, such as private organizations, to join. “Technically, it wasn’t a vote on dissolution,” says ESF chief executive Martin Hynes, “but there would have been de facto dissolution had members not voted to approve the changes in statute.” Hynes says that the ESF will now focus on “science services” such as peer-reviewing grant proposals or evaluating research institutes.

Calls for proposals for existing programmes will not be renewed, he says, but one or two current activities will continue, including the operation of several expert panels, such as the Nuclear Physics European Collaboration Committee. Funding will also be stripped back from a high of about €60m a year in 2012 to just €2m this year, with an associated reduction in staff from around 130 to 30.

Financial-viability test

The new structure will come into force at the end of 2015, once the plan has been subjected to a “financial-viability test” in May, and formally approved first by the ESF’s governing council and then by the assembly in November. For Hynes, however, money is not the stumbling block. “The financial viability is pretty well proven,” he says. “The question is whether there will be enough members to carry the organization forward with credibility.” Hynes adds that many of the existing members from Europe’s larger countries will probably leave, but he hopes that other organizations will join, such as the AXA Research Fund. “We would be happy if we had 20 members in the new organization,” he says.

According to Peter Fletcher, head of international relations at the UK’s Science and Technology Facilities Council (STFC), most of the French and German member organizations have already resigned, while the STFC and the other UK research councils are in the process of doing so. Fletcher describes the creation of Science Europe and the new-look ESF as “a positive opportunity for European science”.

Physics World Special Report: India

Physics World India Dec 2104 cover — Physics World Special Report India 2014.

This year has been one of change for India. In May, some 800 million eligible voters went to the polls in an election that was won by the Bhartiya Janata Party. Led by Narendra Modi, the party went on to form a coalition government called the National Democratic Alliance.

Our Special Report, which you can read free online, kicks off by looking at how science is faring under Modi’s fledgling administration. Indeed, in September, Modi was personally on hand at the Indian Space Research Organisation (ISRO) to laud engineers who had just carefully manoeuvred the Mars Orbiter Mission into position around the red planet – a feat that announced India as a major player in space exploration.

Modi’s personal interest in ISRO will not only please the organization’s chairman K Radhakrishnan, who we interview for the report, but could also be seen as a sign that the new administration is serious about boosting science in the country.

(more…)

Literature of the lab

We are living through a heyday for films tackling physics and astronomy. New, full-length movie dramas about the lives of Stephen Hawking (The Theory of Everything) and Alan Turing (The Imitation Game) have been released. Gravity was a box-office and critical success last year, while the planet-hunting Interstellar movie could well follow in its footsteps. There’s also a new season – the eighth – of the evergreen TV series The Big Bang Theory.

But what about the use of physics in literature? Is it good, bad or indifferent? I decided to check out some recent “physics-lit” to find out.

Destination Geneva

One lab that features in several recent novels is CERN near Geneva. The top-seller here is Angels and Demons (2000), a thriller by Dan Brown. CERN, though, is no more than a prop: it’s the setting for a murder and a theft (of a quarter-gram of antimatter). The tale is compelling, although the writing about CERN is rather pedestrian. “Looming before them was a rectangular, ultramodern structure of glass and steel,” runs a typical sentence.

Another bestseller (according to the adverts) is Robert Sawyer’s Flashforward (1999), which envisions an event, triggered by the Large Hadron Collider (LHC), that makes the world’s entire population black out and have visions of life 21 years in the future. Here, too, CERN’s a prop. There’s a chase in the LHC tunnel, but descriptions are again rather plodding, and you’ll guffaw at the author envisioning physicists being able to discover the Higgs boson (in 2009) simply by noting green lights on the ALICE console.

You’ll find better writing, but an even more outlandish plot, in Robert Harris’s 2011 thriller The Fear Index, whose main character is a former CERN physicist who now works in finance. The book has a few lab scenes and some well-crafted descriptions: “Up ahead, framed by the distant mountains, CERN’s huge rust-coloured wooden globe seemed to rise out of the arable fields like a gigantic anachronism: a 1960s vision of what the future was supposed to look like.” (Actually, the globe was built in the 2000s, though you could say it looks a bit retro.) The lab, Sawyer continues, resembles “an old university in northern England – ugly functional office blocks from the sixties and seventies spread over a big campus, scruffy corridors filled with earnest-looking people, mostly young, talking in front of posters advertising lectures and concerns. It even had the same academic odour of floor polish, body heat and canteen food.”

Different in tone is Catalyzed Fusion by former CERN physicist Francis Farley, whose book’s blurb dubs it “a sizzling romance and a romp with subatomic particles”. Featuring “love, discovery and adventure in the city where nations meet and beams collide”, it culminates in a death caused by a 50 tonne concrete shielding door at the synchrocyclotron – though, for me, the glider scenes above Geneva are the most vivid.

Other fictional labs

Not all lab literature is fiction. The Cuckoo’s Egg, (1989), by Lawrence Berkeley Laboratory astronomer Clifford Stoll, is about his real-life hunt for a spy (the “cuckoo”) who had hacked into an LBL computer and installed a program (the “egg”) that is fed privileges and information. The book provides a genuine sense of LBL, thanks to descriptions of such things as the lack of ceiling tiles, the bicycle ride up and down the steep Cyclotron Road, and the fog-bound, Oz-like San Francisco in the distance. Astonishingly, the book also provides a sense of the Internet, too, as a place – a special, wild arena, where one can communicate instantly with anyone all over the globe yet also be hidden, trackable only from clues in time lags, styles of computer commands, and phone and network tracers.

A Hole in Texas (2004), by Herman Wouk, is a novel about a fictional Higgs finding. It has one brief scene at the abandoned Superconducting Super Collider site in Texas. Despite the fact that Wouk won a Pulitzer prize for another book, the lab description is flat. The protagonists pass by “several huge bleak windowless buildings to a sizeable long low structure stretching off into the fog”. One character says “this brings back memories”, but we never learn them.

Weep for ISABELLE: a Rhapsody in a Minor Key (2003), by former Brookhaven National Laboratory physicist Mel Month, is about the rise and fall of an accelerator at the lab. Subtitled “A Historical Novel”, it unfolds through lengthy ruminations in the heads of the omniscient narrator and in the imagined heads of key (real) actors. But these voices are nearly impossible to distinguish. Not only is there no sense of place in this 600+ page book, but no sense of character either, which makes its prose thick, muddy and featureless. Reading it’s like trying to swim through porridge.

The critical point

Critical Mass (2014) is a satirical novel by “Duronimus Karlof”, which is clearly a pseudonym for someone who’s enough of an insider to make wicked fun of current practices in research, grant-getting and science policy, but also to not want his real name known. I couldn’t put it down, even though it zapped much of what I hold dear, including philosophy of science and California. At one point, contemplating an envisioned laboratory, the protagonist thinks “I liked the notion that our staff would be forced to live in close quarters, where they would not help but share ideas and discuss work out of hours…where the young people would inevitably start to worry about who was sleeping with whom, and where the achievements of Harry working on Project X might spur on Joe who was working on Project Y. The whole set-up seemed ideal to me in every respect.”

This whetted my appetite for more novels that explored the particular hothouse feature of laboratories, whose day-to-day of human experience blurs work and social life so intensely. What literature have I overlooked? E-mail me and I’ll discuss them in a future column.

Asteroids, not comets, gave Earth most of its water

Most of the water that sustains life on Earth probably came from asteroids rather than comets. That is the conclusion of scientists working on the Rosetta space mission, who have measured the levels of hydrogen isotopes in the comet 67P/Churyumov–Gerasimenko. The ratio of deuterium to hydrogen in the comet is much greater than the ratio found on Earth, which suggests that comets supplied Earth with only a small fraction of its water.

Although water blankets 71% of the Earth’s surface, its abundance puzzles scientists. The Earth formed with the other planets in a disc of gas and dust around the newborn Sun. This protoplanetary disc was hot close to the Sun and cold far away. Because the Earth is close to the Sun, it formed in a hot region that should have been fairly dry.

So how did the Earth get its water? Comets had once seemed to be a promising source: they come from the solar system’s frozen outer reaches and harbour ice that vaporizes when they approach the Sun. If comets struck he Earth after its formation, they could have delivered the water that makes up the oceans and our bodies. If this happened, water on comets should have the same isotope composition as water here on Earth. In particular, comets should have the same ratio of deuterium to hydrogen as found on Earth.

Halley’s fluke

In 1986 scientists got a chance to determine the origin of terrestrial water when the best known comet of all – Halley’s Comet – approached the Earth. Surprisingly, the comet’s deuterium to hydrogen ratio was twice the terrestrial ratio. Rather than abandon an attractive theory, however, many scientists dismissed the Halley result as a fluke.

But then in 1996 and 1997, two other bright comets lit up the sky as they passed near to Earth: Hyakutake and Hale–Bopp. Both also had twice the terrestrial deuterium to hydrogen ratio, providing even more evidence that comets did not give the Earth most of its water.

But there was still hope for the comet model. All three comets – Halley, Hyakutake and Hale–Bopp – originated in the Oort cloud, a reservoir of comets far beyond the orbit of Pluto. But some comets come from the Edgeworth–Kuiper belt, which is just past Neptune’s orbit and whose largest members are Pluto and Eris, the latter discovered in 2005. Comets from this reservoir might have terrestrial deuterium levels, but these are usually faint and hard to observe.

In 2010 astronomers succeeded in detecting deuterium in a comet from the Edgeworth–Kuiper belt. Unlike the other comets, this one, named Hartley 2, had a deuterium level matching terrestrial water, reviving the idea that comets delivered water to the Earth.

Just a nice story

“It was a nice story, wasn’t it?” says Kathrin Altwegg, a Rosetta scientist at the University of Bern in Switzerland. “Now with our finding, I guess this idea is going to disappear again.”

In August, and to great fanfare, the European Space Agency’s Rosetta spacecraft arrived at an Edgeworth–Kuiper comet named 67P/Churyumov–Gerasimenko (see “Rosetta rendezvous with comet at long last”).

Today, Altwegg’s team reports that this comet also has high levels of deuterium. In fact, the level is even higher than Halley’s Comet, coming in at 3.4 times the terrestrial level – making it the largest deuterium to hydrogen ratio ever seen in a comet.

Jumbled understanding

“It’s surprisingly high,” says Paul Weissman of the Jet Propulsion Laboratory in Pasadena, California, a Rosetta scientist who was not involved with the new work. “This somewhat jumbles trying to understand where the Earth’s water came from.” Still, Weissman is less ready than Altwegg to assert that comets contributed only a tiny amount of water to the Earth.

At the very least, the finding means that Edgeworth–Kuiper comets span a range of deuterium ratios. Altwegg says that most terrestrial water likely arose from asteroids that hit the Earth. By studying meteorites – most of which come from asteroids – scientists know that asteroids have terrestrial deuterium levels. The Earth was also born with some water as well. Of course, asteroid impacts can be deadly – just ask a dinosaur – but if asteroids did indeed give us most of our water, we might not exist without them.

The research is described in Science.

There is much more about the Rosetta mission in this feature article by its project scientist Matt Taylor: “Rendezvous with a comet”