Prof. Graeme Ackland at the School of Physics has received significant EPSRC funding for electronic structure calculations using density functional theory.
The award comes through the United Kingdom Car-Parrinello Consortium (UKCP) collaboration, which has been expanding for 25 years since it was established in 1991 to fund Physics and EPCC to write the first parallel computing density functional theory code. Ackland is the only ever-present co-investigator. UKCP is one of the most prolific collaborations in UK Science, publishing 106 papers in 2015 including Edinburgh-led studies on advanced titanium alloys and the physics of high pressure hydrogen.
Since UKCP began, Density Functional Theory has established itself as the standard method for solving the many-body quantum mechanics of electrons in solids and liquids. It provides a way to calculate a full range of material properties for substances, including properties which are impractical to measure and for materials which have yet to be synthesized.
The 4-year grant is worth over £5M, split 80% for supercomputing at UoE's ARCHER facility and 20% staff costs.
The project will provide resources for School researchers Graeme Ackland, Andreas Hermann, Ingo Loa, Miguel Martinez-Canales to continue their studies on high pressure materials, thermoelectrics, planetary interiors and fundamental understanding and interpretation of Raman, infrared, X-ray and neutron scattering experiments carried out within CSEC.
European astronauts have arrived in Edinburgh to have training from scientists at the University. The visitors from the European Space Agency will undergo training in astrobiology to understand how to collect samples during planetary missions to minimise contamination and how to collect appropriate samples that can be used to search for habitable conditions elsewhere and maybe even life.
They will be given lectures in the subject and carry out laboratory work, in addition to using Arthur's Seat in the city centre to learn about geology and how to select samples for further study.
Their training will include how to search for signs of life in rocks, how to take samples with minimal risk of contamination, and how to analyse geological samples in the lab.
Taking part are Mathias Maurer, who joined ESA in 2010 and is scheduled to complete his basic astronaut training this year. His experience includes spending 16 days underwater to test hardware and experiments for the International Space Station, as well as testing exploration strategies and tools for future missions to Mars.
He will be joined by Pedro Duque, who has worked on many space missions with ESA and NASA, and qualified for one of the first European long-term missions to the International Space Station. His spaceflight experience includes a nine-day mission on the Space Shuttle Discovery, and the 10-day Cervantes mission on the International Space Station.
Their visit forms part of the ESA's Pangaea course, which is designed to provide European astronauts with introductory and practical knowledge of Earth and planetary geology.
The course is intended to prepare astronauts to effectively partner planetary scientists and engineers in designing exploration missions.
The course also aims to give astronauts a solid knowledge in the geology of the Solar System by learning from leading European scientists.
Professor Charles Cockell of the School of Physics and Astronomy, and head of the UK Centre for Astrobiology, leads the ESA astronaut training in astrobiology and geomicrobiology.
Professor Cockell said: "We are really excited to be sharing our knowledge and expertise with European astronauts, in a visit which puts us at the forefront of future human exploration missions beyond Earth and introduces Europe's new astronauts to science relevant for their future work."
Professor Annette Ferguson has won a Friedrich Wilhelm Bessel Research Award from Alexander von Humboldt Foundation in recognition of her research into the histories of nearby galaxies.
Scientists and scholars, internationally renowned in their field, who in the future are expected to continue producing cutting-edge achievements, which will have a seminal influence on their discipline beyond their immediate field of work, are eligible to be nominated for a Friedrich Wilhelm Bessel Research Award. Award winners are honoured for their outstanding research record.
As part of the award, Annette will spend 6 months at the Leibniz Institute for Astrophysics in Potsdam collaborating with scientists on galactic archaeology projects.
Near the end of the last millennium, our Universe was discovered to be undergoing an accelerated expansion. The physics underlying this acceleration, however, remains one of the Cosmos's darkest secrets. It could be attributed to a new "Dark Energy" force that fills the Cosmos or the presence of the Cosmological Constant predicted by Einstein. But for the two decades since this discovery, there has also been the possibility the acceleration is due to a change in Einstein's Theory of General Relativity. In particular, high hopes were assigned to an extension by a new constituent of the Universe that shares similar properties to the Higgs field.
Researchers at the Royal Observatory in Edinburgh have now discovered that if this field existed it should change the speed of Gravitational Waves from the speed of light, unlike Einstein's theory where these speeds agree. If the speeds did agree, the change in gravity would have messed up the good agreement with the largest structures we observe in our Universe. A difference between the speeds is already at odds with indications from indirect measurements. But with the advent of Gravitational-Wave astronomy marked by the recent detection in the Laser Interferometer Gravitational-Wave Observatory (LIGO), the clear measurement of the speed of Gravitational Waves can now be realised, and so unravel this darkest secret of our Universe.
Agreement between the speeds will be strong evidence for the Cosmological Constant that Einstein once considered his biggest blunder. With the new observing runs of the LIGO and VIRGO experiments in 2017, the crucial observation is expected in time for the 100th anniversary of Einstein's Constant.
Lucas Lombriser, one of the authors, says: “Last year’s direct gravitational wave detection has opened up a new observational window to our Universe. It is like being able to hear when one was only seeing. Our results give an impression of how this new sense will guide us in solving one of the most fundamental problems in physics.”
A long-standing puzzle on the origin of stardust recovered from meteorites has finally been solved thanks to the identification of the effect of a nuclear reaction in the composition of stardust grains.
During their lifetime, stars with masses four to eight times the Sun’s blow off their outer layers generating a nebula around them full of stardust and grains. The chemical composition of such dust and grains reveals important clues on the nuclear processes that have contributed to their formation.
The Solar System is believed to have formed from such a nebula. And while most of the original dust was destroyed to make up new rocks and planets, including the Earth, a small fraction survived the destruction process. This special dust, recovered from meteorites, can be used to trace the evolution of the nebula from which the planets were born and to understand the physical processes inside the stars where the grains formed. But tracing the grains to specific types of stars turned out to be surprisingly difficult.
While intermediate mass stars (roughly six times heavier than the Sun) are seen by infrared telescopes to produce huge amounts of dust, however, grains recovered from the Solar System meteoritic record so far did not seem to match the composition expected from these stars.
A new study, led by Maria Lugaro from Konkoly Observatory (MTA-CSFK) and published in Nature Astronomy, solves this problem by identifying, in the make-up of some meteoritic stardust grains, the effect of the nuclear reactions that occur in these particular stars.
The breakthrough was possible thanks to experiments carried out at the Laboratory for Underground Nuclear Astrophysics (LUNA). LUNA observed that the probability for the fusion of protons and 17O (a heavier type of the oxygen we breathe) to occur is twice as large as previously thought (Bruno et al., Physical Review Letters, 117, (2016) 142502). This effect is clearly observed in some stardust grains, resolving the mystery of the missing grains from intermediate-mass stars.
LUNA is currently the only underground accelerator worldwide specifically devoted to the study of nuclear reactions of astrophysical interest. The facility is hosted by the Laboratori Nazionali del Gran Sasso of the Italian Institute for Nuclear Physics (INFN) and is located under more than one kilometer of rocks.
Maria Lugaro says: “The long-standing question of the missing dust was making us very uncomfortable: it undermined what we know about the origin and evolution of dust in the Galaxy. It is a relief to have finally identified this dust thanks to the renewed LUNA investigation of a crucial nuclear reaction.”
“The results of this study prove once again the importance of precise and accurate measurements in the laboratory of the nuclear reactions that take place in stars – says Prof Marialuisa Aliotta, who led the UK team of LUNA for the PRL study – It is a great satisfaction to know that we have contributed to solving a long-standing puzzle on the origin of some stardust grains.”
LUNA is an international collaboration, involving about 40 scientists from 14 institutions in Italy, Germany, Hungary and the UK. The Collaboration Spokesperson is Prof Paolo Prati, from the University of Genova, Italy.
The Institute for Astronomy's Prof. Catherine Heymans has been awarded the 2017 George Darwin Lectureship by the Royal Astronomical Society. The Lecture is given annually, on a topic in astronomy, cosmology or astroparticle physics.
Professor Catherine Heymans is a world-leading observational cosmologist who is well known for her innovative and ground-breaking work in the field of weak gravitational lensing. In recognition, she holds a Personal Chair at the University of Edinburgh. She is the principal investigator for two successive major research grants from the European Research Council that support her team’s research on the Dark Universe and Beyond Einstein Gravity Theories. Since completing her PhD in 2004, Prof. Heymans has co-authored over 100 well-cited articles in peer-reviewed journals. She is a founding member of the Young Academy of Scotland. Professor Heymans is devoted to promoting the public’s understanding of her research. She has appeared in a wide range of events, at numerous Science Festivals, and has written a number of articles for the popular Institute of Physics science magazine 'Physics World'. Her TEDx talk on the Dark Side of the Universe has had over 8000 views on YouTube showing that she is an accomplished public speaker. For these reasons, Professor Heymans is awarded the George Darwin Lecture.
The Large Underground Xenon (LUX) dark matter experiment, which operates beneath a mile of rock at the Sanford Underground Research Facility in the Black Hills of South Dakota, has completed its search for the missing matter of the universe – one of the most sought for goals in physics and astronomy. Final results are published in Physical Review Letters, with an editorial comment to highlight their significance.
Since 2013, the experiment has led worldwide direct searches for dark matter, in which evidence for the scattering of dark matter particles in a terrestrial detector is sought. The final result from the 2014-2016 run, recently accepted for publication in PRL, pushes the sensitivity of the instrument to a final performance level that is 4 times better than originally expected, and a further improvement on its existing world lead. Despite seeing no sign of a signal, the results rule out large fractions of the theoretical parameter space, constraining tightly the nature of dark matter.
Data analysis continues, searching for other possible rare signals in the data. The instrument itself is now being decommissioned and removed from the deep underground laboratory, in preparation for installation of its successor, LUX-ZEPLIN. Expected to begin taking data in 2019, this instrument is over twenty times larger, and expected to be over a hundred times more sensitive still. The University of Edinburgh is one of the leading institutions in LUX, contributing the Executive Chair of the collaboration, and is a participant in LZ.
These results reflect that LUX is now some twenty times more sensitive to dark matter than any of its predecessors. While if Nature had been kinder, we might have made a discovery, our results have greatly narrowed the possibilities for what dark matter might be - itself an important result. A new generation of experiments are now coming online or being built, including our own LUX-ZEPLIN. The search for dark matter remains a top priority. Says Prof Alex Murphy, The University of Edinburgh
Astronomers around the world are poised to discover billions of new stars, galaxies and solar system objects, thanks to newly released data from a major survey of the skies involving University of Edinburgh researchers.
Scientists are poised to make fresh discoveries about the Universe, thanks to newly released data from a major astronomy survey. Results from a four-year project to capture digital images of the sky should enable astronomers around the world to discover billions of new stars, galaxies and solar system objects. The project, involving Edinburgh scientists, will also enable researchers to study the farthest reaches of the universe and gain insights into elusive dark energy and dark matter.
Images in the study have been taken using a 1.8-metre telescope at the summit of Haleakalā on Maui, Hawaii. The technology is known as the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS). It captured images of patches of sky - each about 36 times the area of the moon - every 30 seconds for four years. The telescope’s regular imaging means that fast moving objects and exploding stars can be tracked across nearly the whole sky. Images from the project, being released by the Space Telescope Science Institute and the University of Hawaii, can be analysed to identify and catalogue astronomical objects. Data from the survey has been shared in advance with astronomers in the team. Already, this has led to discovery of hundreds of supernovae – exploding stars that give off massive amounts of energy as they die. It has enabled scientists to see individual stars in nearby galaxies, and to discover giant streams of stars in our own Milky Way. The survey dataset is being released in two stages. The first gives an average value for the position, brightness, and colours of all the recorded objects in the sky at a particular point in time.
A further release next year will provide a catalogue of information, and allow access to individual images for each time frame. The database will include information on individual snapshots of a given region of sky.
The Pan-STARRS project was undertaken by an international collaboration including the Universities of Edinburgh and Durham, and Queen’s University Belfast.It was supported by NASA and the National Science Foundation.
“This rapid, repeating survey has enabled us to discover very rare events in which a massive black hole shreds a passing star, which otherwise would have been impossible to spot. Releasing the data will now enable astronomers round the world to study huge numbers of distant stars and galaxies in ways we can't even guess." said Professor Andy Lawrence, of the University’s School of Physics and Astronomy
A new theoretical model of DNA as a "recolourable" polymer may explain why specific "epigenetic" patterns on the genome can survive from one cell generation to the next and allow cellular memory.
Every cell in our body contains the same DNA. Nevertheless, a brain cell is clearly very different from, say, a liver cell, in terms of which genes are active and inactive. The specialisation into different types of cells is made possible by "epigenetics" (literally, "beyond the genetic information"). Epigenetics acts through biochemical markers called "post-translational modifications" which are deposited onto histone proteins -- the proteins needed to package the DNA inside the nucleus. Epigenetic marks vary from cell to cell, allowing each cell to have its own identity. Nonetheless, epigenetic marks are very dynamic: they are gained and lost by histones all the time, and many are removed during replication. This then begs the questions, how does a cell remember its own identity throughout its life and how is its identity passed down to the progeny cells when it divides?
Davide Michieletto, in collaboration with Davide Marenduzzo and Enzo Orlandini (Padova) have formulated a new model to address these questions. The model treats the complex of DNA and histones (also called "chromatin") as a polymer made of beads, where each bead corresponding to a few histones (with their corresponding DNA). In the model, the polymer beads are "coloured" based on their epigenetic state, and this can be changed dynamically mimicking the action of "writer" proteins, enzymes found in the cell. The epigenetic colour is then recognised by "readers", which model chromatin-bridging proteins which have an affinity for a given epigenetic mark. The model displays an abrupt first-order-like transition between a swollen and epigenetically "disordered" chromatin and a collapsed and "ordered" one, where the whole polymer has the same colour. The first order nature of the transition is important: it implies that there is hysteresis and memory, and the researchers have shown that, following a (simulated) replication event, the system is able to return to the same ordered state (so the corresponding cell will keep its identity).
The findings therefore strongly suggest that epigenetic memory may be made possible through a positive feedback loop between "reader" and "writer" proteins which couple the 1D epigenetic patterning to the 3D chromatin folding.
Dark matter, the elusive material that accounts for much of the Universe, is less dense and more smoothly distributed throughout space than previously thought, according to a new study co-led by astronomers at the University of Edinburgh. The international team of scientists studied wide-area images of the distant universe, taken from the European Southern Observatory in Chile. They applied a technique based on the bending of light by gravity - known as weak gravitational lensing - to map out the distribution of dark matter in the Universe today. Their study represents the largest area of the sky to be mapped using this technique to date.
The new results contradict previous predictions from a survey of the far-off universe, representing a point in time soon after the Big Bang, imaged by the European Space Agency's Planck satellite. This previous study used a theoretical model to project how the Universe should appear today. The disagreement between this prediction and the latest direct measurements suggests that scientists' understanding of the evolving modern day Universe is incomplete and needs more research.
The latest study, published in Monthly Notices of the Royal Astronomical Society, was carried out by a team jointly led by the University of Edinburgh, the Argelander Institute for Astronomy in Germany, Leiden University in the Netherlands and Swinburne University of Technology, Australia in an ongoing project called the Kilo Degree Survey, or KiDS. It was supported by the European Research Council.
"Our findings will help to refine our theoretical model for how the Universe has grown since its inception, improving our understanding of the modern day Universe.” says Dr Hendrik Hildebrandt of the Argelander Institute for Astronomy in Germany.
"This latest result indicates that the cosmic web dark matter, which accounts for about one-quarter of the Universe, is less clumpy than we previously believed.” said Dr Massimo Viola of Leiden University in the Netherlands.
"Unravelling what has happened since the Big Bang is a complex challenge, but by continuing to study the distant skies, we can build a picture of how our modern Universe has evolved.” said Professor Catherine Heymans of the University of Edinburgh's School of Physics and Astronomy.