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Partial eclipse, meteorites and northern lights enthral a nation

this photograph of the Sun taken during the eclipse clearly shows a sunspot — Spot on: this photograph of the Sun taken during today’s eclipse clearly shows a sunspot. (Courtesy: David Bloomfield)

Earlier today millions of people in north-western Europe had the opportunity to see a partial eclipse of the Sun – or a total eclipse for the lucky few in northern Norway and the Faroe Islands. Although it was a bit hazy here in Bristol, we were treated to spectacular views of the Moon covering 87% of the Sun. We have put up a Flickr album of images taken by colleagues here at IOP Publishing including the amazing photo above. It was taken by David Bloomfield and clearly shows a sunspot in the upper-left portion of the Sun.

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New US philanthropy group picks physicist as boss

Marc Kastner, a physicist at the Massachusetts Institute of Technology (MIT), has become the first president of the Science Philanthropy Alliance (SPA) – a new grouping of six organizations aiming to increase private funding for fundamental research in the US. Kastner began the appointment earlier this week, having taken a leave of absence from MIT.

The alliance – composed of the Howard Hughes Medical Institute, the Kavli Foundation, the Gordon and Betty Moore Foundation, the Research Corporation for Science Advancement, the Alfred P Sloan Foundation and the Simons Foundation – formed two years ago. The alliance’s goal is to increase the value of philanthropic funding to fundamental research – currently estimated at about $2bn – by another $1bn within five years.

The SPA was created following concern that funding for basic research has dwindled in the US, with R&D funding at its lowest level – as a percentage of the federal budget – since the 1960s Apollo era. In addition, funding has shifted towards applied research, which Kastner feels neglects the importance of basic science. “We know historically that some of the greatest breakthroughs in technology have come about in that kind of discovery-driven research,” he says, pointing out that the creation of the Global Positioning System in 1995 evolved from fundamental research carried out several decades earlier.

Funding research

Kastner says that although private funding cannot make up the losses suffered from decreased government support, philanthropists are still in a position to make a big difference. To do this, he says that the alliance needs to show potential donors why fundamental research is important, as well as the technologies that can result from such research. “I think people forget about this,” says Kastner. “They see that you can write software and do wonderful things with computers, and they forget that this came out of decades of fundamental research.”

Kastner adds that the alliance will also “put in front of potential philanthropists ideas of how they could really make a difference and the satisfaction they could get out of it”. The alliance supports around 16 universities – and will soon add non-profit research laboratories and more universities – that share the same goals of increasing levels of fundamental research and have created funds to do so.

Key experience

Kastner has experience of securing philanthropic funding, having done so in his role as head of MIT’s physics department, a position he held for nine years. In November 2013 US president Barack Obama nominated him to head the Department of Energy’s Office of Science, which manages much of the nation’s basic-science research, but his appointment stalled in Congress last year with the position yet to be filled.

Have alien civilizations built cosmic accelerators from black holes?

Has an advanced alien civilization built a black-hole-powered particle accelerator to study physics at “Planck-scale” energies? And if such a cosmic collider is lurking in a corner of the universe, could we detect it here on Earth?

Brian Lacki of the Institute for Advanced Studies in Princeton, New Jersey, has done calculations that suggest that if such an accelerator exists, it would produce yotta electron-volt (YeV or 10²⁴ eV) neutrinos that could be detected here on Earth. As a result, Lacki is calling on astronomers involved in the search for extraterrestrial intelligence (SETI) to look for these ultra-high-energy particles. This is supported by SETI expert Paul Davies of Arizona State University, who believes that the search should be expanded beyond the traditional telescope searches.

The nightmare of particle physics is the dream of astronomers searching for extraterrestrials
Brian Lacki, Institute for Advanced Studies

Like humanity, it seems reasonable to assume that an advanced alien civilization would have a keen interest in physics, and would build particle accelerators that reach increasingly higher energies. This energy escalation could be the result of the “nightmare scenario” of particle physics in which there is no new physics at energies between the TeV energies of the Standard Model and the 10²⁸ eV Planck energy (10 XeV) – where the quantum effects of gravity become strong. “The nightmare of particle physics is the dream of astronomers searching for extraterrestrials,” says Lacki.

An important problem facing alien physicists would be that the density of electromagnetic energy needed to reach the Planck scale is so great that the device would be in danger of collapsing into a black hole of its own making. However, Lacki points out that a clever designer could, in principle, get round this problem and “reaching [the] Planck energy is technically allowed, if extremely difficult”.

Not surprisingly, such an accelerator would have to be rather large. Lacki believes that if electric fields are used for acceleration, the device would have to be at least 10 times the radius of the Sun. However, a magnetic synchrotron-type accelerator could be somewhat smaller. As for what materials could be used to make the accelerator, Lacki says that normal materials could not withstand the strong electromagnetic fields. Indeed, one of the few places where such a high energy density could exist is in the vicinity of a black hole, which he argues could be harnessed to create a Planck-scale accelerator.

“Vast amounts of pollution”

Colliding particles at tens of XeVs is only half the battle, however. Lacki calculates that the vast majority of collisions in such a cosmic collider would be of no interest to alien researchers. To get useful information about Planck-scale physics, he reckons that the total collision rate in the accelerator would have to be about 10²⁴ times that of the Large Hadron Collider. “As such, accelerators built to detect Planck events are extremely wasteful and produce vast amounts of ‘pollution’,” explains Lacki.

While much of this pollution would be extremely high-energy particles, that in principle could reach Earth, it is unclear whether they could escape the intense electromagnetic fields within the collider. Furthermore, like colliders here on Earth, the builders of a cosmic machine would probably try to shield the surrounding region from damaging radiation. Indeed, Lacki’s analysis suggests that neutrinos are the only particles that are likely to reach Earth.

These neutrinos would have energies that are a billion or more times greater than the highest energy neutrinos ever detected here on Earth. However, unlike their lower-energy counterparts, these accelerator neutrinos would be much easier to detect because they interact much more strongly with matter. Lacki calculates that the majority of such neutrinos passing through the Earth’s oceans will deposit their energy in the form of a shower of secondary particles. While the oceans are far too murky for physicists to detect the light given off by the showers, Lacki reckons that the sound of a shower could be detected by a network of hydrophones in the water. However, because these neutrinos are expected to be extremely rare, he calculates that about 100,000 hydrophones would be needed to have a chance of detecting the neutrinos.

Whole of the Moon

Another possibility, albeit less sensitive, is to use the Moon as a neutrino detector. Indeed, the NuMoon experiment is currently using a ground-based radio telescope to try to detect showers created when 10²⁰ eV neutrinos smash into the lunar surface.

While the detection of YeV neutrinos would not be proof that an alien accelerator exists – some theories suggest that they could be produced naturally by the decay of a cosmic strings – Lacki says that spotting such high-energy particles would be an important breakthrough in physics.

While Davies is keen to expand SETI, he does identify one important drawback of looking for cosmic colliders. “My main problem is that once the [alien] experiments are done, there would be no need to keep the thing running, so unless there are mega-machines like this popping up all over the place, there would be only transient pulses,” he told physicsworld.com.

Davies believes that it is very difficult for humans today to understand why an advanced civilization would want to build a Planck-scale collider. “Why do it? Perhaps to create a baby universe or some other exotic space–time sculpture,” he speculates. “Why do that? Perhaps because this hypothetical civilization feels it faces a threat of cosmic dimensions. What might that threat be? I have no idea! However, a civilization that knows a million times more than humanity might perceive all sorts of threats of which we are blissfully unaware.”

Lacki’s calculations are described in a preprint on arXiv.

Paul Davies has written a feature article for Physics World about SETI called “The eerie silence”

A multiverse play divides opinion

The stage lights rise. A man and woman meet in a cute way – “Do you know why it’s impossible to lick the tips of your elbows?” she asks – they chat momentarily, and separate. The lights blink off and on; the pair resume their previous positions and meet the same way, but with another result. The lights blink again: same people, another permutation. Perturbations continue of the same basic situation, caused by slightly different gestures, phrasings and reactions.

The play is Constellations by Nick Payne, and it first opened in 2012 to an enthusiastic reception in a 90-seat space at London’s Royal Court Theatre. It is now on Broadway at the 622-seat Samuel J Friedman Theatre, where it is scheduled to run through to at least 15 March. It also has a UK tour coming soon. The man is Roland, the woman is Marianne, and they are standing on a platform of dark hexagonal tiles, beneath and surrounded by huge white (sometimes blue or purple) balloons. They could be ordinary people in a party room, huge people in space surrounded by stars, or tiny people surrounded by atoms. The staging changes slightly as the actors proceed through turning points in a relationship: meeting, seduction, marriage, betrayal, impending death. The choice of scenes, and their variations, are not random but diverge in key ways: the pair sleeps together, they don’t; he’s unfaithful, then she is; the tumour is benign, the tumour has metastasized and affects her speech, and so forth.

Variations on a scene is an age-old theatrical device. In Constellations it appears to acquire new meaning due to the characters’ professions: Roland is a bee-keeper, Marianne a quantum cosmologist. Through Marianne’s explanations of her work the author seems to prime us to view the play as a kind of “multiverse”, containing slightly branching paths from the same starting point.

Does it work? It depends. I saw the Broadway incarnation from the last row of the balcony. A friend of mine, a successful playwright, saw it from the third row. We had different reactions, and the two taken together answer that question.

Replaying a scene with variations is a common theatrical idea. It was used, for instance, in Sure Thing (1993) a 10-minute play by David Ives in which a couple on a blind date keep restarting their conversation until they romantically connect, and in Alan Ayckbourn’s series of plays Intimate Exchanges (1983). The film Sliding Doors (1998) depicts two different paths that a character’s life may take as the outcomes of one turning point, as does the musical If/Then (2014). To me, up in the balcony, much of Constellations seemed like a repeat of this familiar theatrical device; it was like watching an acting exercise: “Let’s try it this way!” Since the branching paths in this 70-minute play only last a minute or so, just as you begin to take any particular vignette seriously, or see a character begin to crystallize, the sequence ends and another begins. You care less about any one character because you are asked to care about so many fleeting ones. I did get caught up, however, by Marianne’s impending death: all paths come to an end, her mortality reinforced by the falling of the balloons/stars/atoms in the final variations.

On the other hand, my friend in the third row was enthusiastic. “Theatrical fireworks!” he said. “It’s not like Sure Thing. This play takes us to deeper emotions and darker places.” From close up, he appreciated how expertly the actors – Jake Gyllenhaal and Ruth Wilson – made full and instant commitment to each variation, which is not easy to do without tripping into caricature. “Maybe it’s not a great addition to dramatic literature, but it offers the opportunity for great performances – which is a different thing.” My friend also thought the play was successful in forging characters out of multiple short variations. “This play shows us the core of a character – how a single person behaves in different ways in response to different stimuli. The different variations allow you to see the same character logic.”

My friend and I also differed on the use of scientific language. Using the atomic world as a metaphor for human interactions is a familiar literary device, reaching all the way back to Lucretius’ De Rerum Natura in the 1st century BC and continuing in the present day (Björk’s latest album, released in January, includes a song called “Atom dance”). Such atomic language is not necessarily insightful: while it can be used to develop genuine insights, as in some John Updike novels and Michael Frayn’s Copenhagen, it can also become a mere gimmick. I found Marianne’s lines about multiverses, quantum theory, relativity and string theory distracting; I heard them as the author trying to give us the key to the play and the human interactions in it, and it didn’t open any doors. Roland’s discourses on beekeeping – an activity that requires an immense amount of practical knowledge in observing nature while controlling it – offer a better metaphorical grip on the human condition. Yet their characters’ personas imply that Marianne’s cosmological language is more profound. My fears seemed to be realized when, after Marianne outlines the difference between relativity and quantum mechanics, Roland gazes her and says, “This is really sexy, by the way!” My friend, on the other hand, wasn’t bothered by the quantum language, hearing it as Marianne talking to Roland, whose interest she wants to encourage and who she knows won’t get it, rather than to the audience.

Constellations‘ cast has star power; the audience applauds Gyllenhaal and Wilson the minute they walk onstage before they’ve even said anything, and waits for them in long lines at the stage door exit afterwards. Is it a successful play? That depends on who’s performing it, how close you sit, and how forgiving you are of physics terms used outside the laboratory.

Samuel J Friedman Theatre, New York City, US

Diamond bull’s-eye collects polarized photons at a rapid rate

A new optical grating shaped like a “bull’s-eye” that is extremely efficient at collecting photons from diamond nitrogen vacancy (NV) centres has been built by physicists in the US. The device can collect nearly three million photons per second from a single NV, which is the highest value reported to date. The grating could find use in a number of emerging technologies including nanoscale sensors, single-photon sources and quantum memories.

Atomic impurities, or defects, in natural diamond lead to the pink, blue and yellow colours seen in some diamonds. One such defect, the nitrogen vacancy (NV) centre, occurs when two neighbouring carbon atoms in diamond are replaced by a nitrogen atom and an empty lattice site.

Entangled with photons

For anyone trying to build a quantum computer, NVs are useful because they have an electronic spin that is extremely well isolated from the surrounding lattice – so if an NV is placed in a certain spin state, then it will remain in that state for a long time, even at room temperature. What is more, an NV’s electron spin can be entangled with the polarization state of a photon, and such spin–photon entanglement might help in the development of quantum networks and distributed quantum computers of the future.

NVs in nanoscale diamonds could also be used as biological probes and sensors because they are non-toxic, stable and can easily be inserted into living cells. They are also capable of detecting the very weak magnetic fields that come from surrounding electronic or nuclear spins. This means that they can be used as highly sensitive magnetic-resonance probes capable of monitoring local spin changes in a target material across distances of just tens of nanometres.

Efficiently collecting NV light

When illuminated with green laser light, an NV centre emits red light by fluorescence. The intensity of this light depends on the orientation of the NV’s electron spin. A major challenge here is to efficiently detect this light; and the more light that can be detected, the better the NV application, says Dirk Englund of the Massachusetts Institute of Technology (MIT). Collecting this light has proved to be difficult until now because of the high refractive index of diamond, which traps light by total internal reflection. Previous attempts to overcome this problem have included coupling NVs to optical cavities to enhance the light emitted from the defects, and building solid immersion lenses around NVs.

Now, Englund and colleagues at MIT, together with researchers at Columbia University in New York and Element Six in California, say that by etching a circular, “bull’s-eye”-shaped grating in the diamond membrane containing the NV, they can collect nearly three million photons per second from the structure. This is the highest value reported to date from a single NV.

The bull’s-eye grating consists of concentric slits etched into a diamond membrane containing the NV. The diamond membrane has a thickness that is about half a wavelength of visible light. The grating is centred on the NV and its period satisfies the so-called second-order Bragg condition. This helps to scatter light out of the membrane, say MIT team members Luozhou Li and Ed Chen. “The scattered light from each grating interferes constructively out of the plane of the membrane and into the far field – and it is this phenomenon that allows us to collect significantly more photons,” explain the researchers.

Enduring spins

Moreover, the researchers say that they have also measured a spin-coherence time for the NV (the time that it maintains its spin state) of around 1.7 ms. This value not only compares well with the highest reported spin-coherence times measured in previous NVs at room temperature, but also proves that the bull’s-eye fabrication process does not degrade the spin properties of an NV.

“The efficiency with which we can collect photons from an NV determines how fast we can measure the NV’s spin state,” Englund explains. “The more fluorescence we detect, the higher the signal. Detecting more photons is crucially important for many NV technologies, such as sensing, communication and computing, and with our circular grating, we are able to collect about an order of magnitude more fluorescence than is possible from an NV in unpatterned diamond.”

“Nice advance”

Ronald Walsworth of Harvard University, who was not involved in the work, says that “using a bull’s-eye diamond grating to enhance the photon-collection efficiency of single NV centres in diamond, while maintaining good NV spin-coherence time, is a nice advance that may aid diamond-based sensing and metrology”.

Englund and colleagues believe that such efficient photon collection should allow for a whole new range of hitherto impossible experiments, such as “non-demolition” measurements of NV spins. “Here, you could measure an NV spin and then ‘act back’ on this spin state,” explains Englund. “We are also using our technique to make medium-scale quantum registers that would contain tens of quantum bits (or qubits) made from NVs – for quantum-sensing applications.”

The bull’s-eye device is described in Nano Letters.

This article first appeared on nanotechweb.org

Guide to the solar eclipse

Solar eclipse captured by Hinode craft — Solar eclipse of 2012, which darkened parts of the US and south-east Asia. (Courtesy: JAXA/Hinode)

On Friday, our old friend the Moon will swing by to remind us that she’s not just there to reflect the Sun’s light; she can sometimes block it out too. A total solar eclipse will be visible to those lucky few people living in the Faroe Islands or the Norwegian archipelago of Svalbard. Many others across Europe, North Africa and Russia will be treated to the (almost as good) spectacle of a partial solar eclipse.

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Evidence for recent star formation seen at Milky Way’s centre

Stars could be forming in the inhospitable environment near Sagittarius A*, which is the supermassive black hole at the heart of the Milky Way. That is the conclusion of an international team of astronomers that has discovered a possible signature of low-mass star formation just two light-years from the centre of our galaxy – a region that was previously thought to be too hostile for such activity. If confirmed, these observations identify a “laboratory” where astronomers can study star formation – and even possible planetary formation – near a supermassive black hole.

Stars form when a cloud of gas becomes dense enough to collapse in on itself under the influence of its own gravity. This process is affected by the environment surrounding the cloud. Close to a supermassive black hole, the self-gravity of the cloud will be countered by “tidal shear”, which is the stretching force that results from the intense gravitational pull of the black hole. Forming stars near a supermassive black hole is therefore expected to be very difficult, because the self-gravity of a cloud must be strong enough to overcome the tidal shear. Indeed, a star-forming cloud would have to be unusually dense to avoid being torn apart.

Searching for signatures

Understanding star formation near supermassive black holes is important because these objects are known to reside at the heart of most large galaxies. Previous observations of the central few light-years of the Milky Way had focused on a population of about 200 massive, young and very bright stars in tight orbits around Sagittarius A*. These stars are only a few million years old and prompted scientists to wonder whether they somehow manage to form in their current locations in spite of their close proximity to the black hole, or whether they form further from the black hole and then migrate in?

Motivated by this mystery, Farhad Yusef-Zadeh of Northwestern University and collaborators looked for evidence of even younger stars close to Sagittarius A*, which would demonstrate that star formation in the area is an ongoing process. “We have been searching for signatures of more recent star formation within a few light-years of the black hole for some time,” Yusef-Zadeh says.

Looking for signs of star formation in this region is difficult because the Earth lies in the disc of the Milky Way, and our view of the galactic nucleus is obscured by interstellar dust particles. Scientists therefore rely on telescopes that use non-optical wavelengths, such as radio telescopes, to peer through the dust and probe activity at the galactic centre. New capabilities of one such telescope, the Very Large Array (VLA) in New Mexico, were key in allowing Yusef-Zadeh and collaborators to make their recent discovery of small sources in one arm of activity near Sagittarius A*.

Heated discs

The team identified these small sources as candidate photoevaporative protoplanetary discs – “proplyds” – which are areas of dense, ionized gas and dust surrounding young, newly formed stars. The proplyd candidates are between 10,000 and 100,000 years old, and they lie along the edge of a large molecular cloud. It is likely that this cloud produced the discs by providing a reservoir of gas to feed the star-formation activity.

Radio-telescope image showing two proplyd candidates located near Sagittarius A* — Bow shocks: Radio-telescope image highlighting two proplyd candidates (see arrows) located near Sagittarius A*. These objects are in the shape of bow shocks caused by a stellar wind from hot stars orbiting close to the supermassive black hole. (Courtesy: F Yusef-Zadeh *et al*.)

The region surrounding these proplyds is blasted with harsh ultraviolet radiation streaming from hot stars orbiting close to Sagittarius A*. The gas of the proplyds is heated and stripped away by the radiation from these stars and characteristic shock waves are formed around the discs on the side facing the galactic centre. Both the proplyds themselves and the “bow shocks” surrounding them are visible in Yusef-Zadeh’s observations.

Planetary possibilities

Unlike the young massive stars that have previously been identified in the galactic centre, the proplyd candidates in this study are associated with low-mass stars – objects of less than about one solar mass. The analysis by Yusef-Zadeh’s team has led the researchers to speculate that it may in fact be easier for low-mass stars to form in the hostile surroundings of the black hole than it is for them to form elsewhere in the Milky Way. In addition, the rate at which material is lost from such proplyds is expected to be low, so there is a chance for the disc to eventually form planets. With that comes the tantalizing possibility that as telescope resolution and data-analysis techniques improve, we may even be able to watch planet formation occur near Sagittarius A*.

“The inner few light-years of the galaxy is clearly a unique environment,” says Yusef-Zadeh. Determining exactly what role this environment plays in the formation of stars is the challenge. Further work is necessary to determine whether the extremes of these surroundings hinder or, in fact, help star formation, but the observations in this study are an important step in the direction of better understanding.

This research is described in Astrophysical Journal Letters.

The following video abstract shows the locations of the proplyd candidates relative to Sagittarius A*, and provides more information about how the observations were made and analysed

What's the latest matter with antimatter?

Mind over antimatter: Jeffrey Hangst at the ALPHA experiment at CERN.

By Tushna Commissariat at CERN

While visiting CERN, the world’s biggest particle-physics laboratory, it’s easy to get swept up by the excitement of the Large Hadron Collider and its detectors, especially in the run up to it being switched back on in the coming weeks. But CERN is also host to a variety of other equally exciting experiments that probe some of the biggest unanswered questions in science, such as the experiments that probe the unwieldy world of antimatter. Indeed, CERN’s antimatter programme has received considerable attention in the past, especially thanks to the now-famous book (and later, film) Angels and Demons, where some antimatter was supposedly stolen from the laboratory and used to build a bomb! Suffice to say, antimatter is of interest to physicists and the public alike and so I caught up with physicist Jeffrey Hangst, who is spokesperson of the Antihydrogen Laser Physics Apparatus (ALPHA) experiment, which I also had the chance to visit.

a view of the ALPHA 2 apparatus — Antimatter factory: a view of the ALPHA 2 set-up.

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Nanowire-based electrode could lead to better supercapacitors

A new type of electrode that could lead to the development of more efficient and lighter supercapacitors has been unveiled by researchers in India. The electrode has a new hybrid structure that is made from iron and nickel nanowires, and could be used to boost the capacitance, current density and charging/discharging rates of big capacitors used to store large amounts of electrical energy. The electrodes are inexpensive and environmentally friendly to produce, say the researchers, and could someday be used to make supercapacitors to power a range of devices, from mobile phones to electric cars.

Supercapacitors store energy by separating positive and negative charge through electrochemical reactions that involve the exchange of electrons and ions at the interfaces between two electrodes and an electrolyte. These devices combine the large-scale energy-storage properties of batteries with the rapid charging times and long lifespans of conventional capacitors. In principle, supercapacitors could be used to create electric cars that could be fully charged in minutes, and mobile phones that would charge in seconds. Today, however, a supercapacitor is much larger and heavier than a conventional battery that holds the same amount of energy.

Porous shell

Created by Ashutosh Singh and colleagues at the S N Bose National Centre for Basic Sciences in Kolkata, the new electrode has a two-part nanostructure comprising a conductive iron–nickel core and a hybrid iron-oxide–nickel-oxide outer shell. The electrodes are made in two stages. First, arrays of iron–nickel nanowires are created through electro-deposition into a porous, anodized alumina-oxide template. After the template is dissolved away, the second step of the process sees the wires temporarily exposed to oxygen at a temperature of 450°. This forms a porous iron-oxide–nickel-oxide hybrid shell around the iron–nickel core.

“The advantage of this core/shell hybrid nanostructure is that the highly porous shell nanolayer provides a very large surface area for redox reactions and reduces the distance for the ion-diffusion process,” explains Singh. Complementing the outer shell, the iron–nickel core provides a highly conductive pathway by which electrons may be transported to the current collector.

In addition, the way that the new electrode is structured means that no binding material is required to attach the redox active materials to the current collector – which is unlike conventional carbon or graphene electrodes. This, say the researchers, will help to lower the overall weight of the supercapacitor design.

Promising results

The researchers say that initial tests of their electrode design have been promising. In comparison with equivalent non-hybrid iron/iron-oxide or nickel/nickel-oxide electrodes, the new design achieved a higher capacitance of about 1415 F/g. The charging/discharging rate is about 2.5 A/g, and the current density is significantly higher than both nickel and iron-based non-hybrid electrodes. The electrode was also able to maintain up to 95% of its initial capacitance after 3000 charging–discharging cycles.

Cary Pint of Vanderbilt University in the US calls the new electrode design “innovative”, and highlights its potential relevance to other areas, such as catalysis and sensing applications. “The design of materials with complex hybrid functionality, as is demonstrated in this work, is a key pillar for innovation in next-generation high-power chemical-storage systems,” he adds.

With the initial tests of their demonstration electrode complete, the researchers are now moving to develop a functioning supercapacitor based around the hybrid-electrode design. Then they will test the functional performance and temperature stability of the device. A complete supercapacitor is expected to be developed in about 8–10 months, Singh told physicsworld.com. The researchers say that they will also be exploring avenues of commercial production.

The electrode is described in the Journal of Applied Physics.

Was Bruno Pontecorvo a spy?

Frank Close (centre) speaking at Prospect magazine HQ on 12 March 2015 — Reflecting on – Frank Close (centre) discusses the life of the Italian physicist Bruno Pontecorvo, who defected to the Soviet Union in 1950.

Like all good publications, Prospect has a strapline about itself – “the leading magazine of ideas”. Physics World is also about ideas, although sadly our magazine, great though it is, doesn’t have adverts for Cartier watches, Embraer executive jets or the Taj Exotica Resort & Spa in the Maldives as Prospect does. Clearly, some people with ideas have more money to spend than others.

I was kindly invited last week by the deputy editor of Prospect, Jay Elwes, to an event he hosted at the magazine’s headquarters in central London. The event featured the University of Oxford physicist Frank Close, who has just published a new book on the life and times of Bruno Pontecorvo. Close was on hand to discuss the key themes of the book, which is entitled Half Life: the Divided Life of Bruno Pontecorvo. Elwes described the attendees as a “small, high-powered group”, including as it did Pauline Neville Jones, the former chair of the UK’s Joint Intelligence Committee and Jonathan Evans, the former director-general of the British security service MI5.

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Partial eclipse, meteorites and northern lights enthral a nation