School of Physics and Astronomy

Doors Open Day is an annual opportunity for the public to visit buildings and institutions across Scotland.

Take a guided tour of the School of Physics and Astronomy and go behind the scenes of physics research on Saturday 29 September at the James Clerk Maxwell Building on the King’s Building campus. You will have the opportunity to experiment with a variety of hands-on activities alongside staff and students, including having the chance to make and take away your own slime!  Tours include a visit to the anechoid chamber (part of the acoustics group), a bio-physics lab (studying the life, death and motion of bacterias) and a rheo-imaging lab (looking at unusually behaving mixtures). There is also the opportunity to visit activities delivered by other Schools based on the King's Building campus.

On Saturday 29 & Sunday 30 September, you will have the chance to talk to astronomers from the Institute for Astronomy about their work on galaxy evolution, planet formation and computer simulations of the Universe. There will be talks, demonstrations and hands-on activities. Relax on the sofa in the astronomers’ corner while discussing the big questions of the Universe and get an insight into the working life of an observatory. These events take place at the Royal Observatory, Edinburgh.

TRAIN@Ed research fellowship for candidates with a background in experimental particle physics and machine learning.

The TRAIN@Ed research fellowship programme, an ambitious scheme with the intention of bringing international researchers to the UK, is now open to applications. This is part of a €7.1 million Horizon 2020 Marie Skłodowska-Curie actions COFUND grant awarded to the University of Edinburgh.

The School of Physics and Astronomy, in collaboration with industrial partner Tindeco Financial Services, is looking for applicants with a background in experimental particle physics and machine learning, and a strong interest in financial applications (in particular: portfolio construction, risk management and systematic investment management). Candidates must submit a proposal outlining their vision on the collaborative research to be conducted during the three-year fellowship.

Eligible candidates will have finished their PhD ideally around two years previous to and no more than ten years beyond their application. They will not have lived and worked in the UK for more than 12 months in the 3 years immediately prior to the submission deadline.

Full details of the scheme and opportunities are found on the TRAIN@Ed site.

Interested candidates should get in touch with Christos.Leonidopoulos [at] ed.ac.uk (Christos Leonidopoulos.)

The deadline for expression of interest is 15 October 2018.

Scientists gain valuable insight into how hydrogen behaves at extreme conditions, such as those found within Jupiter and Saturn.

A study of hydrogen at extreme temperatures and pressures has enabled researchers to build a clearer picture of conditions within Jupiter and Saturn – where hydrogen accounts for much of the mass. The findings also shed light on the fundamental physical properties of the gas, which is the focus of research into a sustainable form of energy known as fusion.

An international team of researchers carried out sophisticated experiments using the most advanced laser in the world, the National Ignition Facility in California, US. Powerful laser beams were fired across the stadium-sized facility towards a hydrogen sample, and optical sensors were used to detect changes in the sample. Researchers were able to observe how hydrogen behaved as the pressure and temperature were raised to 6 million times that of Earth’s atmosphere. Conditions were similar to pressures found in the interior of Jupiter.

Their observations helped pin down the physical conditions at which hydrogen begins to behave like a liquid metal. This elusive phase of the element has been little understood by scientists for many decades and has rarely been recreated in experiments.

The study, carried out by the University of Edinburgh with researchers in France and the US, was published in Science and supported by the Engineering and Physical Science Research Council.

Dr Stewart McWilliams, who took part in the study, said:

Being able to undertake high-energy experiments using the world’s biggest laser has afforded us valuable insights into one of the most important materials making up the planets of our universe, as well as future energy sources.

Research suggests that the surface properties of growing cell membranes and expanding bacterial colonies, for example, are fundamentally distinct.

Growing interfaces are dynamic boundaries - usually between two different phases of matter - which represent many nonequilibrium phenomena.

Almost all growing interfaces fall into the celebrated Kardar-Parisi-Zhang (KPZ) universality class. One feature of KPZ interfaces is that in one dimension the interface reaches a stationary state in which it has the statistical properties of a random walk:  the lateral width of the interface scales with the square root of its length.

A fascinating realisation of a growing interface is the lamellipodium, which is the leading edge of a growing mesh of actin filaments in a motile cell. The lamellipodium is an unusual growing interface in that it pushes against a constraining cell wall, producing a ratcheting effect, and enables the cell to move.

Inspired by the lamellipodium interacting with a cell wall, Justin Whitehouse (Condensed Matter CDT PhD student), Richard Blythe (Reader in Complexity Science) and Professor Martin Evans (Chair of Statistical Physics) have investigated the fundamental properties of an interface that is impeded by a diffusing barrier that either lies ahead of the interface (as in the case of the cell wall) or behind the interface (as in the case of a growing bacterial colony). When the diffusing barrier is ahead of the interface (and interacts with its peaks), they find the classic KPZ behaviour. The situation changes when the barrier is behind, interacting with the interfacial troughs:  this creates a new universality class where the interface is less rough than a random walk, scaling as the cube root of its length.

The paper was made the Editors' Suggestion in Physical Review Letters.
 

The European Physical Society (EPS) Nuclear Physics Division Board has announced the winners of PhD theses in the areas of experimental, theoretical or applied nuclear physics.

Carlo Bruno received this award for his thesis on Underground measurement of hydrogen-burning reactions on 17,18O at energies of astrophysical interest, which he completed in 2017 while at the School of Physics and Astronomy, The University of Edinburgh. Results from his thesis have been published in Physical Review Letters and Nature Astronomy. Carlo is currently working at the University as a Postdoctoral Research Associate on nuclear reaction studies at storage rings within the School’s Institute for Particle and Nuclear Physics.

The European Physical Society awards PhD prizes every three years to the best theses in nuclear physics.  Winners give a plenary talk on their work and are presented with a diploma during the European Nuclear Physics Conference. 

The Gabor Medal is awarded annually for acknowledged distinction of interdisciplinary work between the life sciences with other disciplines.

The Royal Society announced that this year the medal is awarded to Professor Cait MacPhee CBE in recognition for her seminal contributions to understanding protein aggregation that inform our approach to diseases such as Alzheimer’s and diabetes, and for opening up new opportunities for creating self-assembled functional biopolymers. 

Research on protein behaviour

Cait’s research concerns the behaviour of proteins: the molecules that are responsible for the vast majority of functions in living organisms. The controlled self-assembly of proteins into well-defined structures and functional assemblies is essential to our well-being, however occasionally protein self-assembly takes place inappropriately. When this happens in the body it typically causes disease, and familial diseases as well as diseases of ageing (such as Alzheimer's Disease, Parkinson's Disease, cataract and type II diabetes) are all recognised to be the result of improper protein self-assembly. Protein self-assembly can also cause havoc in industrial processes including the production of biopharmaceuticals (e.g. insulin). When this occurs, the pharmaceutical is often lost as an irretrievably tangled mass of gelled protein. All is not lost, however: the self-assembly of proteins also underpins the texture of foodstuffs including egg, meat and milk products. It is understanding this process of self-assembly - to prevent or reverse disease, or to drive the development of new materials and foodstuffs - that forms the focus of Cait’s research efforts.

Honours and Fellowships

In 2016 Cait was recognised in the Queen’s New Year's Honours list for her services to women in physics, and was elected to become Fellow of the Royal Society of Edinburgh (RSE).

The Gabor award was created in memory of the engineer Dennis Gabor, Nobel Prize winner and inventor of holography.

Prof Cait MacPhee commented:

I am delighted to receive this award from the Royal Society in recognition of this interdisciplinary work.

Prof Arthur Trew, School of Physics and Astronomy’s Head of School reported:

We are incredibly pleased by this recognition of Cait’s research contributions and collaborations.   My congratulations to Prof MacPhee for this award. 

Tiny creatures that lived in the dark – either underground or below the sea floor – were the dominant life forms on Earth for much of the planet’s history, a study suggests.

Microscopic organisms, including bacteria, were the most abundant forms of life on Earth from about 2 billion years ago until 400 million years ago, when plants began to spread across the land. During this era, these organisms weighed around 10 times as much as all other life on the planet combined, which offers insight into the evolution of life on Earth, according to the study.

Researchers from the Universities of Edinburgh and Aberdeen used data on the current make-up of life on the planet to work out how this has changed over billions of years. They did this by estimating how changes to the chemical composition of the atmosphere and oceans through time – which are recorded in rocks found around the world – would have affected the ability of different life forms to thrive.

Life on Earth is thought to have begun around 3.8 billion years ago with single-celled organisms. Dinosaurs first appeared around 230 million years ago, and the earliest mammals are believed to have evolved millions of years later. Plants dominate life on the planet today in terms of their combined weight of carbon, which is about 500 billion tonnes, researchers say. Underground bacteria are now the second most abundant life form, with a combined weight of about 100 billion tonnes of carbon.

Researchers hope their work will help develop new techniques to study microscopic fossils from ancient underground regions. The study, published in Journal of the Geological Society, was supported by the European Union’s Horizon 2020 Research and Innovation Programme.

Dr Sean McMahon, of the University of Edinburgh’s School of Physics and Astronomy, said:

Prehistoric life on Earth was like an iceberg – most of it was found below the surface. The total mass of life on the planet was far smaller before plants took over.

Professor John Parnell, of the University of Aberdeen’s School of Geosciences, said:

Life underground was the norm on Earth. Until quite recently, the biggest habitat was below ground.

Scientists have discovered fresh insights into the metallic core at the centre of our planet.

An international team of researchers carried out sophisticated experiments to replicate conditions at the Earth’s core. Using high energy laser beams and optical sensors, they were able to observe how samples of nitrogen behaved at more than 1 million times normal atmospheric pressure and temperatures above 3,000C. Their observations confirmed that, under such conditions, nitrogen exists as a liquid metal.

The findings give scientists valuable insight into how nitrogen behaves at extreme conditions, which could aid understanding of how the planets were formed. It may help to explain why Earth is the only planet known to have an abundance of nitrogen in its atmosphere – where it exists as a gas. Nitrogen in the air could emerge from deeper within the planet, where, for example, it could mix with other liquid metal. In addition, the findings could also shed light on how the planet’s atmosphere evolved and how it may develop in future.

The study, carried out by the University of Edinburgh with researchers in China and the US, was published in Nature Communications. It was supported by the Engineering and Physical Science Research Council and the British Council.

Dr Stewart McWilliams of the School of Physics and Astronomy said: “Earth’s atmosphere is the only one of all the planets where nitrogen is the main ingredient – greater even than oxygen. Our study shows this nitrogen could have emerged from deep inside the planet.”

Local secondary school pupils receive award and gain an insight into studying physics

The School of Physics and Astronomy and the Ogden Trust hosted an awards ceremony for the ‘School Physicist of the Year’.  The ceremony rewarded the most deserving high school students who are currently in year 3, based on their progress in Physics.  18 pupils based in schools in Edinburgh were selected by their Physics teachers and 15 were able to attend the evening, along with around 35 parents and teachers. The students were rewarded with a £25 National Book Token and a certificate enabling them to apply to events and programs organised by the Ogden Trust.

The event also enabled school pupils to gain a flavour of studying physics at University level. Academic staff, research colleagues and physics undergraduates students from the School of Physics and Astronomy shared information on their work and experience here, guests got the chance to take part in demonstrations and experiments, and an inspirational talk on ‘Squidgy Business’ was given by Prof. Wilson Poon as he shared information on how businesses use his expertise in soft matter.

Thank you for a lovely evening last night, the award ceremony was most enjoyable and very inspiring not only for our young people  but I'm  sure for all who attended

A new stochastic equation for active, growing interfaces predicts the evolving shape of a cellular membrane.

From a physicist's point of view, perhaps the most intriguing feature of biological systems is that they are constantly held away from thermodynamic equilibrium by active processes: the inert atoms and molecules of classical statistical mechanics are replaced by active entities which consume energy and may move of their own volition. Likewise active matter - which is composed of many such active entities - can itself grow and change shape.

The range of lengthscales spanned by theories of active matter is stunningly large. Consider a cell: on the one hand it is the active component of bigger systems such as tissues, on the other hand it is itself an active system, whose constituents are those proteins regulating the whole cellular machinery.

Francesco Cagnetta (Higgs STFC PhD student), Martin Evans (Professor of Statistical Physics) and Davide Marenduzzo (Professor of Computational Biophysics) analyse the effects of activity on growing interfaces and how this produces the striking patterns that have been puzzling experimentalists studying red blood cell membranes.  Specifically, the authors extend the celebrated Kardar-Parisi-Zhang (KPZ) equation, known to predict the universal features of many out-of-equilibrium systems, to deal with the local source of growth provided by membrane proteins.  Their theory proposes an explanation for the self-organisation of proteins: dynamic nanoclusters of proteins are formed which induce travelling waves of growth in the membrane. Intriguingly, these travelling undulations of the membrane are in turn surfed by the protein nanoclusters that produced them!

The work was made an Editors' Selection in Physical Review Letters and has been highlighted by a Viewpoint in APS Physics.