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What type of physics should you do if you want to bag a Nobel prize?

What type of physics should you do if you want to bag a Nobel prize? | Science | Scoop.it

At 11.45 a.m. CET (at the earliest) on Tuesday 7 October, the winner(s) of the 108th Nobel Prize for Physics will be announced in Stockholm. Like just about everyone else, I have no information about who will win – although I do have my suspicions (more on those tomorrow).

Predicting the future is never easy, but help is at hand with a new infographic that Physics World has created charting the history of the physics Nobel by discipline. Using the categories that we apply to articles on physicsworld.com, we have split the 107 prizes since 1901 into seven categories. If you click on the image above, you can see the infographic in all its glory.

The most popular discipline with Nobel committees through the ages is nuclear and particle physics, which accounts for nearly one-third of the prizes. As well as dominating the prizes in the 1950s and 1960s, nuclear and particle physics spreads its tentacles from the very first prize – to Wilhelm Röntgen for the discovery of X-rays – to last year’s prize, which went to François Englert and Peter Higgs for predicting a much more esoteric boson.

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LEDs made from ‘wonder material’ perovskite

LEDs made from ‘wonder material’ perovskite | Science | Scoop.it

A hybrid form of perovskite - the same type of material which has recently been found to make highly efficient solar cells that could one day replace silicon - has been used to make low-cost, easily manufactured LEDs, potentially opening up a wide range of commercial applications in future, such as flexible colour displays.

This particular class of semiconducting perovskites have generated excitement in the solar cell field over the past several years, after Professor Henry Snaith’s group at Oxford University found them to be remarkably efficient at converting light to electricity. In just two short years, perovskite-based solar cells have reached efficiencies of nearly 20%, a level which took conventional silicon-based solar cells 20 years.

Now, researchers from the University of Cambridge, University of Oxford and the Ludwig-Maximilians-Universität in Munich have demonstrated a new application for perovskite materials, using them to make high-brightness LEDs. The results are published in the journal Nature Nanotechnology.

Perovskite is a general term used to describe a group of materials that have a distinctive crystal structure of cuboid and diamond shapes. They have long been of interest for their superconducting and ferroelectric properties. But in the past several years, their efficiency at converting light into electrical energy has opened up a wide range of potential applications.

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Researchers build first 3D magnetic logic gate

Researchers build first 3D magnetic logic gate | Science | Scoop.it

The integrated circuits in virtually every computer today are built exclusively from transistors. But as researchers are constantly trying to improve the density of circuits on a chip, they are looking at alternative ways to build circuits. One alternative method uses nano-sized magnets, in which the magnets possess two stable magnetic states that represent the logic states "0" and "1."

Until now, nanomagnetic logic (NML) has been implemented only in two dimensions. Now for the first time, a new study has demonstrated a 3D programmable magnetic logic gate, where the magnets are arranged in a 3D manner. In comparison to the 2D gate, the 3D arrangement of the magnets allows for an increase in the field interaction between neighboring magnets and offers higher integration densities.

The researchers, Irina Eichwald, et al., at the Technical University of Munich in Munich, Germany; and the University of Notre Dame in Notre Dame, Indiana, US, have published their paper on the 3D magnetic logic gate in a recent issue ofNanotechnology.

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Shining a brighter light on topological transport

Shining a brighter light on topological transport | Science | Scoop.it

Last year we reported on a fascinating experiment that simulated the quantum Hall effect using light.Mohammad Hafezi and colleagues at the Joint Quantum Institute (JQI) of the University of Maryland created a lattice of ring-shaped silicon waveguides that are placed just nanometres apart (see image above). This allows light in one ring to “tunnel”  into a neighbouring ring and make its way across the matrix, hopping from ring to ring.

This orbiting and hopping is analogous to the effect of a magnetic field on electrons in a thin sheet of semiconductor – which is where the quantum Hall effect (QHE) is usually observed.  In the presence of a magnetic field, QHE electrons travel in circular orbits. In the middle of the sheet these orbits are localized, so the semiconductor behaves as an electrical insulator. However at the edges of the sheet the circular orbits are interrupted and electrons are forced to hop from one orbit to the next, making conduction possible.

This edge conduction was simulated by making the lattice out of two slightly different rings that are arranged in square unit cells as illustrated by the image on the right. One type of ring is tuned to resonate with the light used in the experiment. This means that the light can travel around an isolated ring forever, at least in principle. The other type of ring is detuned slightly from the light, which encourages light to jump to a neighbouring ring.
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Researchers develop method for growing single species of single-walled carbon nanotubes

Researchers develop method for growing single species of single-walled carbon nanotubes | Science | Scoop.it

 team of researchers with members from Switzerland and Germany has developed a method for producing a specific single-walled carbon nanotube type with a predefined structure. They describe the procedure in their paper published in the journal Nature. James Tour offers a News & Views piece in the same journal discussing the groundbreaking work done by the team.

Carbon nanotubes, as most are aware, are tubes made of only carbon atoms, and quite often have walls that are just one atom thick (known as single-walled). Because of their unique properties, researchers have been creating and using them in a variety of applications ranging from solar cells, to light detectors and sensors. One serious hindrance to their widespread use has been an inability to mass produce single-walled carbon nanotubes that are all nearly exactly alike. Growing them using conventional methods results in nanotubes that have a variety of different shapes and sizes, thus using them requires separating out the ones that fit specifications, a time consuming and expensive process. In this new effort, the research team has developed a way to produce a "batch" of nanotubes that all have the same characteristics.

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The Surprising Science Behind What Music Does To Our Brains

The Surprising Science Behind What Music Does To Our Brains | Science | Scoop.it

I’m a big fan of music, and use it a lot when working, but I had no idea about how it really affects our brains and bodies. Since music is such a big part of our lives, I thought it would be interesting and useful to have a look at some of the ways we react to it without even realizing.

Without music, life would be a mistake” --Friedrich Nietzsche

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Surprise discovery could see graphene used to improve health

Surprise discovery could see graphene used to improve health | Science | Scoop.it

A chance discovery about the 'wonder material' graphene – already exciting scientists because of its potential uses in electronics, energy storage and energy generation – takes it a step closer to being used in medicine and human health.

Researchers from Monash University have discovered that graphene oxide sheets can change structure to become liquid crystal droplets spontaneously and without any specialist equipment. 

With graphene droplets now easy to produce, researchers say this opens up possibilities for its use in drug delivery and disease detection.

The findings, published in the journal ChemComm, build on existing knowledge about graphene. One of the thinnest and strongest materials known to man, graphene is a 2D sheet of carbon just one atom thick. With a ‘honeycomb’ structure the ‘wonder material’ is 100 times stronger than steel, highly conductive and flexible.

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Self-assembly of gold nanoparticles into small clusters

Self-assembly of gold nanoparticles into small clusters | Science | Scoop.it

Researchers at HZB in cooperation with Humboldt-Universitaet zu Berlin have made an astonishing observation: they were investigating the formation of gold nanoparticles in a solvent and observed that the nanoparticles had not distributed themselves uniformly, but instead were self-assembled into small clusters.

This was determined using Small-Angle X-ray Scattering (SAXS) at BESSY II. A thorough examination with an electron microscope (TEM) confirmed their result. "The research on this phenomenon is now proceeding because we are convinced that such nanoclusters lend themselves as catalysts, whether in fuel cells, in photocatalytic water splitting, or for other important reactions in chemical engineering", explains Dr. Armin Hoell of HZB. The results have just appeared in two peer reviewed international academic journals.

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The Future of Ultrashort Laser Pulses

The Future of Ultrashort Laser Pulses | Science | Scoop.it

Next-generation approaches to the production of ultrashort flashes of laser light – the so-called third generation of femtosecond laser pulses – are stimulating further advances in the investigation of ultrafast processes in the realm of the microcosmos. In the foreseeable future, the new techniques will permit the motions of subatomic particles to be observed in far greater detail than has been possible hitherto. In the new journal Optica, published under the auspices of the Optical Society of America, researchers led by Professor Ferenc Krausz of the Laboratory for Attosecond Physics (LAP) at the Max Planck Institute for Quantum Optics (MPQ), together with a team based at Ludwig-Maximilians Universität (LMU) in Munich describe the underlying technology and the prospects that it will open up.

Techniques for the generation of pulses of laser light that last for a few femtoseconds, first demonstrated in the 1970s, have made giant strides since then. Progress really began with dye lasers that could produce pulses of less than one picosecond in duration. Soon the limits of the technique were extended, and pulses lasting for a few femtoseconds became standard (one femtosecond is a millionth of a billionth of a second, 10-15 s). A light pulse of that duration consists of only a few wave cycles, i.e. a few oscillations of the electromagnetic field. Its shape is such that the amplitude of the oscillations rises to a maximum near the middle of the pulse and then falls off again.

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Finding the 'heart' of an obstacle to superconductivity

Finding the 'heart' of an obstacle to superconductivity | Science | Scoop.it

A team at Cornell and Brookhaven National Laboratory has discovered that previously observed density waves that seem to suppress superconductivity are linked to an electronic "broken symmetry," offering an important clue to why superconductivity doesn't happen at higher temperatures.

"This exotic state has been predicted for decades," said J.C. Séamus Davis, the James Gilbert White Distinguished Professor in the Physical Sciences at Cornell and director of the Center for Emergent Superconductivity at Brookhaven National Laboratory. "It is a pattern of electronic structure in a crystal that has never been seen experimentally before."

The results were reported July 2 online in the Proceedings of the National Academy of Sciences.

Superconductivity, where an electric current moves with zero resistance, is seen in metals cooled almost to absolute zero (−273.15 degrees Celsius or −459.67 Fahrenheit). Newly discovered materials superconduct at temperatures up to around 150 degrees C above absolute zero. Moving that temperature higher – even up to room temperature – could lead to a revolution in motors, generators and power transmission.

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Nanoparticles Improve Stroke Treatment

Nanoparticles Improve Stroke Treatment | Science | Scoop.it

Currently there is just one drug that has been approved for treatment of acute stroke—recombinant tissue plasminogen activator, or t-PA. Essentially it works by thinning blood clots. Researchers at the University of Georgia (UGA) announced last week that they have developed a magnetic nanoparticle that when combined with t-PA can make the drug significantly more effective.

The Georgia researchers injected magnetic nanorods into the bloodstream. When stimulated by rotating magnets the nanorods act as a kind of mixing tool that shakes up blood clots that have already been thinned by t-PA.

The injected nanorods "act like stirring bars to drive t-PA to the site of the clot," said Yiping Zhao, professor of physics at UGA, in a press release. "Our preliminary results show that the breakdown of clots can be enhanced up to twofold compared to treatment with t-PA alone."

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Princeton launches online galleries of prize-winning images and video

Princeton launches online galleries of prize-winning images and video | Science | Scoop.it

he exhibit consists of both still images and video of artistic merit created during the course of scientific research. Forty-four still images were chosen from more than 250 submissions from undergraduates, graduate students, postdocs, staff, and alumni representing more than 25 different University departments. Twelve videos were chosen from more than 50 submissions.

Zach Donnell, a graduate student in molecular biology and one of the 2014 organizers, noted that the exhibit highlights the interplay between art and science. "While the scientific methods behind the exhibit strive for objectivity and consensus, everyone's individual response to the images is subjective and highly personal," he said.

The top three image entrants as chosen by a distinguished jury received cash prizes in amounts calculated by the golden ratio (whose proportions have since antiquity been considered to be aesthetically pleasing): first prize, $250; second prize, $154.51; and third prize, $95.49.

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Fiber optic light pipes in the retina do much more than simple image transfer

Fiber optic light pipes in the retina do much more than simple image transfer | Science | Scoop.it

#scienceHaving the photoreceptors at the back of the retina is not a design constraint, it is a design feature. The idea that the vertebrate eye, like a traditional front-illuminated camera, might have been improved somehow if it had only been able to orient its wiring behind the photoreceptor layer, like a cephalopod, is folly. Indeed in simply engineered systems, like CMOS or CCD image sensors, a back-illuminated design manufactured by flipping the silicon wafer and thinning it so that light hits the photocathode without having to navigate the wiring layer can improve photon capture across a wide wavelength band. But real eyes are much more crafty than that.

A case in point are the Müller glia cells that span the thickness of the retina. These high refractive index cells spread an absorptive canopy across the retinal surface and then shepherd photons through a low-scattering cytoplasm to separate receivers, much like coins through a change sorting machine. A new paper in Nature Communicationsdescribes how these wavelength-dependent wave-guides can shuttle green-red light to cones while passing the blue-purples to adjacent rods. The idea that these Müller cells act as living fiber optic cables has been floated previously. It has even been convincingly demonstrated using a dual beam laser trap. In THIS case (THIS, like in Java programming meaning the paper just brought up) the authors couched this feat as mere image transfer, with the goal just being to bring light in with minimal distortion.

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The borders I crossed

The borders I crossed | Science | Scoop.it

I wanted to become a respected scientist, maybe not a Nobel Prize winner but someone who is capable of making a decent contribution. I started by studying biochemistry at the University of Bucharest. I graduated less than a year after the end of Nicolae Ceauşescu's dictatorship. Free to see the world for the first time, I was eager to get a Ph.D. in the United States. My father, a biology teacher who referred to all trees by their scientific names and often explored the neighboring Măcin Mountains with his students, encouraged me to go.

When I was young, border s were serious, scary things. Crossing the first border required a passport—banned during the dictatorship—a student visa, and a one-way ticket that cost the equivalent of my father's yearly income. I bought my ticket, Bucharest to New York, using three bricks of devalued Romanian currency provided by the Soros Foundation. I waved goodbye to my family at the airport. The first border was the hardest; for the rest of my life, I just pushed my way across them.

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Water's reaction with metal oxides opens doors for researchers

Water's reaction with metal oxides opens doors for researchers | Science | Scoop.it

A multi-institutional team has resolved a long-unanswered question about how two of the world's most common substances interact.

In a paper published recently in the journal Nature Communications, Manos Mavrikakis, professor of chemical and biological engineering at the University of Wisconsin-Madison, and his collaborators report fundamental discoveries about how water reacts with metal oxides. The paper opens doors for greater understanding and control ofchemical reactions in fields ranging from catalysis to geochemistry and atmospheric chemistry.

"These metal oxide materials are everywhere, and water is everywhere," Mavrikakis says. "It would be nice to see how something so abundant as water interacts with materials that are accelerating chemical reactions."

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Learning from origami to design new materials

Learning from origami to design new materials | Science | Scoop.it

A challenge increasingly important to physicists and materials scientists in recent years has been how to design controllable new materials that exhibit desired physical properties rather than relying on those properties to emerge naturally, says University of Massachusetts Amherst physicist Christian Santangelo.

Now he and physicist Arthur Evans and polymer scientist Ryan Hayward at UMass Amherst, with others at Cornell and Western New England University, are using origami-based folding methods for "tuning" the fundamental physical properties of any type of thin sheet, which may eventually lead to development of molecular-scale machines that could snap into place and perform mechanical tasks. Results are reported today in an early online edition of Science.

At a physics meeting a couple of years ago, Santangelo mentioned the unusual properties of a special type of origami fold called Miura-ori to fellow physicist Jesse Silverberg of Cornell, a long-time origami enthusiast. Miura-ori, named after the astrophysicist who invented the technique, is a series folded parallelograms that change the stiffness of a sheet of paper based only on the crease pattern

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Scientists use lasers and carbon nanotubes to look inside living brains

Scientists use lasers and carbon nanotubes to look inside living brains | Science | Scoop.it

A team of Stanford scientists has developed an entirely non-invasive technique that provides a view of blood flow in the brain. The tool could provide powerful insights into strokes and possibly Alzheimer's disease.

Some of the most damaging brain diseases can be traced to irregular blood delivery in the brain. Now, Stanford chemists have employed lasers and carbon nanotubes to capture an unprecedented look at blood flowing through a living brain.

The technique was developed for mice but could one day be applied to humans, potentially providing vital information in the study of stroke and migraines, and perhaps even Alzheimer's and Parkinson's diseases. The work is described in the journal Nature Photonics.

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Addiction showcases the brain’s flexibility

Addiction showcases the brain’s flexibility | Science | Scoop.it

Every day sees a new research article on addiction, be it cocaine, heroin, food or porn. Each one takes a specific angle on how addiction works in the brain. Perhaps it’s a disorder of reward, with drugs hijacking a natural system that is meant to respond to food, sex and friendship. Possibly addiction is a disorder of learning, where our brains learn bad habits and responses. Maybe we should think of addiction as a combination of an environmental stimulus and vulnerable genes.  Or perhaps it’s an inappropriate response to stress, where bad days trigger a relapse to the cigarette, syringe or bottle.

None of these views are wrong. But none of them are complete, either. Addiction is a disorder of reward, a disorder of learning. It has genetic, epigenetic and environmental influences. It is all of that and more. Addiction is a display of the brain’s astounding ability to change — a feature called plasticity  — and it showcases what we know and don’t yet know about how brains adapt to all that we throw at them. 

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Explaining the shape of freezing droplets

Explaining the shape of freezing droplets | Science | Scoop.it

A water droplet deposited onto an icecold surface clearly has more effect than a drop in the ocean: the droplet will freeze in a peculiar way, forming a pointy tip. Scientists of the University of Twente have, in cooperation with colleagues from Paris, Brussels and Munich, found an explanation for this remarkable shape. They used video images and advanced mathematics for this. Insight into this process is also useful for understanding processes like 3D printing. The results are published in the August 1 issue of Physical Review Letters.

It is typically a 'do try this at home' experiment that can be performed using a deep-frozen plate (colder than minus 15 degrees Celsius, preferably) and some water at room temperature. A droplet falling on the plate, will freeze starting at the bottom. It will not stay round, but turn into a conical shape. Existing theories could not explain this shape transformation. In their latest publication, the scientists from the University of Twente now present an explanation. Using their theory, the cone angle can also be calculated. These new insights provide useful information for e.g. icing processes on aircraft wings or for manufacturing technologies like 3D printing, where molten metal drops solidify when hitting a surface.

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Scientists develop pioneering new spray-on solar cells

Scientists develop pioneering new spray-on solar cells | Science | Scoop.it

Experts from the University’s Department of Physics and Astronomy and Department of Chemical and Biological Engineering have previously used the spray-painting method to produce solar cells using organic semiconductors - but using perovskite is a major step forward.

Efficient organometal halide perovskite based photovoltaics were first demonstrated in 2012. They are now a very promising new material for solar cells as they combine high efficiency with low materials costs.

The spray-painting process wastes very little of the perovskite material and can be scaled to high volume manufacturing – similar to applying paint to cars and graphic printing.

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A mathematical theory proposed by Alan Turing in 1952 can explain the formation of fingers

A mathematical theory proposed by Alan Turing in 1952 can explain the formation of fingers | Science | Scoop.it

Alan Turing, the British mathematician (1912-1954), is famous for a number of breakthroughs, which altered the course of the 20th century. In 1936 he published a paper, which laid the foundation of computer science, providing the first formal concept of a computer algorithm. He next played a pivotal role in the Second World War, designing the machines which cracked the German military codes, enabling the Allies to defeat the Nazis in several crucial battles. And in the late 1940's he turned his attention to artificial intelligence and proposed a challenge, now called the Turing test, which is still important to the field today.

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The first supercomputer simulations of 'spin–orbit' forces between neutrons and protons in an atomic nucleus

The first supercomputer simulations of 'spin–orbit' forces between neutrons and protons in an atomic nucleus | Science | Scoop.it

Protons and neutrons are held together at the center of an atom by powerful nuclear forces. A theory that can describe the interaction between just two of these subatomic particles could potentially be extended to predict the existence and properties of more exotic particles, but simulations of such systems using conventional approaches are computationally intensive and have been hampered by a lack of available computing power.

A team of researchers including Keiko Murano and Tetsuo Hatsuda from the RIKEN Nishina Center for Accelerator-Based Science have now developed a method to solve the equations that govern the interactions between particles in the nucleus.

Nucleons, which include protons and neutrons, are made up of fundamental elementary particles known as quarks and gluons. The three quarks that comprise each nucleon are bound together by a force known as the strong interaction, which only acts over distances of a few femtometers—on the scale of the particles themselves. The development of a complete theory that can explain how this force holds the nucleons together in a nucleus has been a long-standing problem in nuclear and particle physics.

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Creating optical cables out of thin air

Creating optical cables out of thin air | Science | Scoop.it

Imagine being able to instantaneously run an optical cable or fiber to any point on earth, or even into space. That's what Howard Milchberg, professor of physics and electrical and computer engineering at the University of Maryland, wants to do.

In a paper published today in the July 2014 issue of the journal Optica, Milchberg and his lab report using an "air waveguide" to enhance light signals collected from distant sources. These air waveguides could have many applications, including long-rangelaser communications, detecting pollution in the atmosphere, making high-resolution topographic maps and laser weapons.

Because light loses intensity with distance, the range over which such tasks can be done is limited. Even lasers, which produce highly directed beams, lose focus due to their natural spreading, or worse, due to interactions with gases in the air. Fiber-optic cables can trap light beams and guide them like a pipe, preventing loss of intensity or focus.

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Researchers demonstrate ultrasonically propelled nanorods spin dizzyingly fast

Researchers demonstrate ultrasonically propelled nanorods spin dizzyingly fast | Science | Scoop.it

Vibrate a solution of rod-shaped metal nanoparticles in water with ultrasound and they'll spin around their long axes like tiny drill bits. Why? No one yet knows exactly. But researchers at the National Institute of Standards and Technology (NIST) have clocked their speed—and it's fast. At up to 150,000 revolutions per minute, these nanomotors rotate 10 times faster than any nanoscale object submerged in liquid ever reported.

The discovery of this dizzying rate has opened up the possibility that they could be used not only for moving around inside the body—the impetus for the research—but also for high-speed machining and mixing.

Scientists have been studying how to make nanomotors move around in liquids for the past several years. A group at Penn State looking for a biologically friendly way to propel nanomotors first observed that metal nanorods were moving and rotating in response to ultrasound in 2012. Another group at the University of California San Diego then directed the metal rods' forward motion using a magnetic field. The Penn State group then demonstrated that these nanomotors could be propelled inside of a cancer cell.

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Crystallography matters

Crystallography matters | Science | Scoop.it

In many ways, crystallography epitomizes the modern scientific era. Max von Laue's pioneering X-ray diffraction experiments in 1912 provided a direct and (with some crucial input from W. Henry and W. Lawrence Bragg) quantifiable link between the macroscopic morphology of crystals and their microscopic atomic structure. The ability to peer inside matter captured the imagination of scientists at the time. This was, after all, a technique that achieved what philosophers had dreamed of for millennia. They weren't to be disappointed: it is fair to say that our understanding of the material world around us — from the constitution of minerals to the molecules that form the basis of life itself — is now rooted in crystallography.

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