School of Physics and Astronomy

Congratulations to Dr Federica Oliva and Dr Israel Osmond who have received Royal Society of Edinburgh research grants.

The Royal Society of Edinburgh’s (RSE) Research Awards Programme opens in spring and autumn each year and aims to support Scotland’s research sector by nurturing promising talent, stimulating research in Scotland, and promoting international collaboration. In this latest round of awards, 92 research projects were selected, funding innovative research across a range of academic fields.

Enhancing photon detector research & development capability

Dr Federica Oliva

Photon detectors record single photons with exceptional precision, enabling advances in physics, astronomy, medicine, and quantum technologies. Future high energy physics experiments, operating at extremely high rates, will further challenge the performance limits of current detector technologies. New devices are needed that are more sensitive, faster, and more reliable over long periods, even in demanding conditions. This RSE grant will support the expansion of facilities in Edinburgh, enabling the testing of silicon photomultipliers for future applications in high energy physics experiments and beyond. The project will strengthen UK capability in advanced photon detection technology, drive innovation across research and healthcare, and help train future experts.

Developing technology for novel hydride superconductor characterisation

Dr Israel Osmond 

Superconductivity, the ability of certain materials to conduct electricity without resistance, has transformative potential for energy transmission and quantum computing, but it is observed at extremely low temperatures (typically below -200°C). Recently discovered hydrogen-based compounds can host superconductivity at temperatures approaching 0°C, but require millions of atmospheres of pressure to stabilise the hydrogen networks beneficial to superconductivity.

Achieving these required pressures requires diamond anvil cells (DACs), where samples are compressed between the tips of two opposing diamonds. This RSE grant will produce bespoke DACs for measuring samples at the low-temperature, high-pressure and high-magnetic field conditions to characterise novel hydride superconductors.

UK scientists open a real-time window to our vast and ever-changing Universe.

UK astronomers are providing public real-time updates on the changes in our Universe, be it exploding stars, belching black holes, or asteroids cruising through our solar system.

The UK-developed software system, Lasair, has been created by a team from the University of Edinburgh, Queen’s University Belfast, and the University of Oxford, to filter millions of events from the Rubin Observatory alerts stream, unlocking new scientific opportunities faster than ever before.

More than a decade in development, Lasair is one of a handful of Rubin data brokers. As a specialist in detecting transient events, it will uncover explosions of stars in distant galaxies that can tell us about the origin of the elements, the expansion of the Universe and the complex physics of black holes.

Lasair will ingest, process, and filter millions of astronomical alerts from the data that Rubin will capture during its 10-year Legacy Survey of Space and Time (LSST). This will enable scientists to focus on significant changes in the sky, from supernovae, variable stars, and gamma-ray bursts to black holes eating stars, and asteroids in the Solar System.

The first Rubin Observatory alerts distributed to researchers around the world were generated the night of 24 February. The alerts contained the flares of new supernovae and the flickers of stars, actively feeding black holes in distant galaxies, and asteroids cruising through our Solar System.

A deluge of data

Every night, powerful computers in the UK will help to crunch the huge influx of data captured by the world’s largest digital camera before serving it up to the science community through the Lasair web portal. The computers that run Lasair are part of a wider data facility constructed on IRIS, a network of powerful, digital research infrastructure for priority astronomy, particle physics, and nuclear physics in the UK. It provides the technology that astronomers around the world will use to unlock the secrets from Rubin. Over the next 10 years, UK scientists will use powerful supercomputers to analyse around 10 million images, captured by the Observatory as part of LSST, identifying and measuring billions of stars and galaxies – most of which have never previously been detected.

Dr Roy Williams of the Institute for Astronomy at the University of Edinburgh has been the lead developer for Lasair for over a decade. He said:

Lasair is a platform to enable custom filtering: each user imagines and creates their own filter. Most nights there will be a massive flow of data that Lasair will strain through those filters, and we hope this flexibility will allow users to find new and unexpected discoveries from this glorious deluge.

Sophisticated software

Professor Bob Mann, Professor of Survey Astronomy at the Institute for Astronomy at the University of Edinburgh, is the Project Leader for UK participation in the Rubin LSST. He said:

The Lasair alert broker is one of the important contributions that UK astronomers are making to the Rubin LSST. Over the course of a decade, the Lasair team have used data from simulations and a precursor sky survey to develop a sophisticated system that will enable astronomers to detect instances of rare time-varying celestial phenomena of different kinds within the deluge of data that will flow from Rubin. Today marks a major milestone for them and the start of an exciting decade of science for astronomers in the UK and beyond.

Lasair is part of a multi-million-pound investment by the Science and Technology Facilities Council (STFC), which is enabling the UK to participate in the groundbreaking Rubin LSST. Across 36 research institutions in the UK, researchers and software developers are addressing scientific and technical challenges that will enable astronomers to make discoveries within the multi-Petabyte dataset that will be captured by the Rubin Observatory over the next 10 years.

The beginning of scientific alerts is one of the last major milestones before Rubin Observatory begins its Legacy Survey of Space and Time (LSST) this year.

Congratulations to the four winners of the inaugural School of Physics and Astronomy Public Engagement Awards.

The School of Physics and Astronomy is proud to announce the winners of its inaugural Public Engagement Awards, recognising outstanding efforts to benefit the School or the communities we serve.

The awards celebrate staff and students who have demonstrated creativity and commitment in sharing physics - whether through digital media, festivals or community partnerships.

Award winners

The Public Engagement Award Winners 2026 are:

• Mia Belle Parkinson - PhD student 
• Ellie Bishop – PhD student
• Dr Miquel Nebot-Guinot – PDRA
• Dr Cheryl Patrick – STFC Ernest Rutherford Fellow

The winners were announced at a School Forum, and certificates were presented by the Head of School, Professor Philip Best.

In addition to the four winners, the panel also recognised outstanding public engagement activity from the Euclid Space Telescope team, the Higgs Centre for Theoretical Physics, and the National Biofilms Innovation Centre.

Professor Philip Best said:

These awards recognise colleagues who dedicate their time and creativity to making physics accessible, relevant and inspiring to external audiences. Their work is immensely valuable to ensuring our research has impact beyond academia, and their efforts strengthen our relationship with the wider community and inspire future generations.

Public engagement contributions and activities 

Mia Belle Parkinson 

Mia’s has shared her passion for science on BBC’s The Sky at Night and in the Daily Mail. She has worked as scriptwriter and narrator for SpaceTV—a role that earned her a 2024 VOX Award nomination for ‘Best Human Performance in E-Learning/Medical Narration’.

She fosters scientific dialogue as the host of The Tartan Tardigrade podcast, interviewing global experts in the field, as the Editor-in-Chief of the Astrosociological Insights Forum, and as the published author of Our AstroLegacy, an insightful read on discovering our place in the universe. She also creates educational space science content on social media.

Ellie Bishop 

Ellie’s outreach involvement includes work with Remote3 (building and programming LEGO mars rovers which are sent to complete challenges at the Boulby Underground Laboratory) where she has acted as mentor and leads programming workshops at events around Scotland.

She was elected LUX-ZEPLIN (LZ) UK Outreach Coordinator in 2024, a role which included organising the Underground Dark Matter Searches UK exhibition stand at New Scientist Live - featuring a walk-in dark matter detector.

Dr Miquel Nebot-Guinot 

Miquel led the Edinburgh contribution to the commissioning of an experimental neutrino physics display (DUNE- UK) at the Royal Society Summer Exhibition 2024. With the help of neutrino-group colleagues, he brought this exhibit to the Edinburgh Science Festival 2025 and to the CERN’s 70^th anniversary UK celebration in Edinburgh. More than 1,000 people visited to find out about the work. The exhibition is now being used for other outreach activities and at science festivals across the UK.

Dr Cheryl Patrick

Cheryl’s main public engagement project has been through the creation of physics board games to teach and inspire school children about particle physics. The games have been taken to CERN’s 70^th anniversary event, outreach events, and local schools.

Cheryl has been working on developing the game Quark Quest, which is designed to cover the Scottish Highers Standard Model curriculum into a product that can be provided to schools. Her goal is to make this accessible to all students and teachers across Scotland.

Looking ahead

The School continues to encourage and support colleagues to embed public engagement within their research and teaching, and recognises the efforts of many other students and staff in public engagement endeavours.

Congratulations to all of this year’s winners and nominees for their dedication to sharing physics.

Scientists have shown that microbes can extract precious metals from meteorites in space, opening new possibilities for sustainable space exploration.

The findings come from the BioAsteroid experiment which was conducted onboard the International Space Station (ISS) at the end of 2020. The researchers investigated how bacteria and fungi interact with meteorite material under microgravity conditions, comparing the results with identical experiments conducted on Earth.

The study involved researchers from Cornell University, including Rosa Santomartino and Alessandro Stirpe, and the University of Edinburgh, including Charles Cockell.

BioAsteroid builds on the team’s earlier landmark space biology mission, BioRock, which showed that microbes could extract useful elements from terrestrial rocks in space. BioAsteroid adds key scientific knowledge about how microorganisms interact with rocks in space, particularly extraterrestrial materials.

The BioAsteroid experiment showed that precious elements such as palladium can be extracted from meteorites under microgravity conditions using the filamentous fungus Penicillium simplicissimum. The researchersfound that extraction efficiency depends on the element of interest, the rock substrate, and the microorganism used.

This is highly relevant for future space biomining scenarios and highlights an increasingly evident reality in the space microbiology community: due to their diversity and plasticity, predicting microbial response to space conditions a priori is very difficult, if not impossible, making experimental testing essential for future space applications.

The team also performed a thorough metabolomics analysis of the samples after spaceflight, to highlight the bioproduction of molecules of interest for future space biomanufacturing efforts, and to better understand the mechanisms involved in microbial response to microgravity during biomining. They demonstrated that both the fungus and the bacterium used in this experiment can interact with the extraterrestrial mineral surface in microgravity by forming biofilms and mycelium. 

These results are relevant in the context of developing sustainable human space exploration, in which crews may establish long-term settlements on planetary bodies such as the Moon or Mars. In these environments, resources will be scarce, and frequent resupply from Earth will be unviable, and the only sustainable solution will be to obtain resources locally. These insights may also support the development of more sustainable biomining strategies on Earth, contributing to reduced resource consumption and lower environmental impact compared to conventional extraction methods.

The research was supported by the United Kingdom Science and Technology Facilities Council, the Leverhulme Trust, the University of Edinburgh School of Physics and Astronomy and Edinburgh-Rice Strategic Collaboration Awards.

In the rapidly evolving world of two-dimensional materials, a small twist can have outsized consequences.

Since the discovery that rotational misalignment between atomically thin crystals can reshape their electronic behaviour, moiré engineering (a technique that manipulates the properties of 2D materials with precise small-angle twists) has become a powerful design principle for quantum matter. Writing in Nature Nanotechnology, researchers now show that magnetism, too, can defy conventional expectations: in twisted antiferromagnetic layers, spin order need not be confined to the moiré unit cell, but can expand into unexpectedly large, topological textures that span hundreds of nanometres.

Most moiré phenomena inherit their defining length scale directly from the interference pattern between lattices. Magnetic order in stacked van der Waals magnets has therefore been assumed to follow the same rule. The new work overturns this assumption. Studying twisted double-bilayer chromium triiodide (CrI₃) with scanning nitrogen–vacancy magnetometry, the authors directly image magnetic fields with nanoscale resolution and observe long-range textures extending well beyond a single moiré cell, up to ~300 nm, an order of magnitude larger than the underlying wavelength.

The behaviour is counterintuitive. As the twist angle decreases, the moiré wavelength grows, yet the observed magnetic texture size evolves in the opposite direction, peaking near 1.1° before vanishing above ~2°. This inversion signals that magnetism is not simply templated by the moiré pattern, but instead emerges from a collective competition between exchange, magnetic anisotropy and Dzyaloshinskii–Moriya interactions, all subtly tuned by relative layer rotation. Large-scale spin dynamics simulations support this picture, revealing the stabilization of extended, Néel-type antiferromagnetic skyrmions spanning multiple moiré cells.

The implications extend beyond fundamental magnetism. Skyrmionic textures are attractive for information technologies because they are compact, topologically protected and movable with minimal energy. Generating them through twist alone, without lithography, heavy metals or strong currents, offers a clean, geometry-based route toward low-power spintronic architectures.

Dr Elton Santos, whose team led the modelling aspect of the project, said:

This discovery shows that twisting is not just an electronic knob, but a magnetic one. We’re seeing collective spin order self-organize on scales far larger than the moiré lattice. It opens the door to designing topological magnetic states simply by controlling angle, which is a remarkably simple handle with profound practical consequences.

By introducing the concept of super-moiré spin order, the work reframes twist engineering as a multiscale tool: atomic alignment gives rise to mesoscale topology. This challenges the prevailing picture that moiré physics is purely local and establishes twist angle as a powerful thermodynamic control parameter that tunes exchange, anisotropy and chiral interactions to stabilize topological phases. Practically, such large, robust Néel-type skyrmionic textures are suited for device integration: their mesoscale size improves detectability and addressability, while their topological protection and insulating host material promise ultra-low dissipation operation. As researchers continue to explore the rich interplay between geometry and quantum interactions, such emergent behaviour may become central to the quest for energy-efficient, post-CMOS computing platforms.

High-pressure experiments reveal two distinct methane phase diagrams and revised melting conditions.

Methane is a deceptively simple molecule and the main constituent of natural gas found within Earth. As such, methane’s behaviour has multi-faceted importance for the fundamental sciences. A gas at ambient conditions, methane transforms to a fluid before crystallizing under pressure. The arrangement of molecules that constitutes the crystalline phase depends on both pressure and temperature, thus a 'phase diagram' can be drawn, mapping out the conditions under which each phase forms.

By conducting dozens of in situ high-pressure and high-temperature Raman spectroscopy experiments, the team at the School of Physics and Astronomy conducted a systematic exploration of the phase diagram, resolving inconsistencies in earlier studies. The experiments yielded two distinct phase diagrams, one that demonstrates phase transformations dominated by kinetics and the other presenting equilibrium states usually reached with time. Furthermore, the study demonstrated that the melting conditions at high pressure are vastly different from those previously reported. These discoveries provide new insights into chemical processes potentially occurring within planetary interiors.

The findings can be found in a paper published in Physical Review Letters by PhD student Mengnan Wang along with colleagues from the School’s Institute for Condensed Matter and Complex Systems. The work was supported by the UKRI Future Leaders Fellowship Mrc-Mr/T043733/1, planetary original diagnostic by Raman spectroscopy, the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement no. 948895, MetElOne).

Dr Mengnan Wang said:

The high pressure studies of methane require a lot of patience and attention – we were waiting for days and sometimes for months to reach the equilibrium state, and we found out that some of the inconsistencies in the earlier melting data could be attributed to photochemical dissociation and/or a reaction induced by high-intensity light sources, a fact which was often missed in the earlier studies.

Scientists at the Dark Energy Survey (DES) collaboration, have released their latest and most detailed picture yet on how the universe has expanded over the last six billion years.

A century of discovery

Around 100 years ago, scientists discovered that distant galaxies appeared to be moving away from Earth. They found that the further away a galaxy is, the faster it recedes, providing the first key evidence that the universe is expanding.

Researchers initially expected that this expansion would slow down over time due to gravity.  However, in 1998, observations of distant supernovae revealed that the universe’s expansion is accelerating rather than slowing down.

To explain this surprising result, scientists proposed the idea of dark energy, which is now thought to drive the universe’s accelerated expansion.

Astrophysicists believe dark energy makes up about 70% of the mass-energy content of the universe, yet we still know very little about it.

Combining four cosmic probes

These recent findings combine results from 18 separate studies and, for the first time, bring together four major techniques for studying dark energy within a single experiment, a milestone envisioned when DES was conceived 25 years ago. These techniques are:

• weak gravitational lensing (distortions in galaxy shapes)
• galaxy clustering
• supernovae
• galaxy clusters

The combination of these techniques enabled scientists to cross-check their measurements and gain a more robust understanding of how the universe behaves.

International collaboration

The Dark Energy Survey is an international collaboration of more than 400 astrophysicists, astronomers and cosmologists from over 35 institutions. The international research team is led by the US Department of Energy’s Fermi National Accelerator Laboratory, with UK support from the Science and Technology Facilities Council (STFC) and six UK universities, including the University of Edinburgh.

Through STFC, the UK is also supporting research programmes that will advance DES science in the next generation of astronomical surveys, including the Vera C. Rubin Observatory, currently under construction in Chile.

Professor Joe Zuntz, Personal Chair of Cosmology, Institute for Astronomy, University of Edinburgh, said:

As well as needing a fantastic telescope, research like this needs supercomputers to tell us what the data actually means. That’s one reason why the UK’s next supercomputer, being hosted in Edinburgh, is so valuable and why I’m proud to develop the programming to help scientists understand what DES’s measurements can tell us about the Universe.

Far reaching science

To study dark energy, the DES collaboration carried out a deep, wide-area survey of the sky between 2013 and 2019, using a specially constructed 570-megapixel Dark Energy Camera mounted on a telescope at the US National Science Foundation’s Cerro Tololo Inter-American Observatory in Chile.

Over six years, scientists collected images and data from hundreds of millions of distant galaxies, billions of light-years from Earth, mapping about one-eighth of the sky.

For the latest results, scientists refined how they use subtle distortions in galaxy shapes, known as weak gravitational lensing, to reconstruct the distribution of matter in the universe over six billion years. They did this by measuring both how galaxies cluster together and how similarly their shapes are distorted by gravity.

By reconstructing the universe’s matter distribution across 6 billion years, these measurements reveal how dark energy and dark matter have influenced the universe’s evolution.

A mystery remains

The team compared their observations with two main theories, one in which dark energy remains constant over time (the standard model of cosmology), and another in which dark energy changes as the universe evolves.

DES found that although the data mostly align with the standard model, broadly agreeing with the most widely accepted theory of the universe, there remains a long-standing discrepancy in how matter clusters in the universe, and this has become more pronounced with the inclusion of the full dataset.

Paving the way

Looking ahead, DES will combine these latest findings with results from other dark energy experiments to explore and test alternative ideas about gravity and dark energy.

The work also helps prepare the ground for future breakthroughs at the upcoming Vera C. Rubin Observatory in Chile to do similar work with its Legacy Survey of Space and Time (LSST).

Congratulations to Professor Steve Tobias who has been appointed a Fellow of the Academy for the Mathematical Sciences.

Fluid dynamics

Professor Tobias is an applied mathematician who conducts research in mathematical aspects of fluid dynamics and magnetohydrodynamics, with applications in both geophysics and astrophysics. He is particularly interested in turbulent flows and turbulent dynamo theory, where the nonlinear interactions occur over a vast range of temporal and spatial scales, necessitating the development of new mathematical and computational techniques. He currently holds the Tait Chair of Mathematical Physics at the University of Edinburgh.

Academy Fellows

The Academy for the Mathematical Sciences has a vision to bring together the UK’s strongest mathematicians across academia, education, business, industry, and government to help solve some of the UK’s biggest challenges and to provide an authoritative, persuasive and influential voice for the whole of the mathematical sciences for the benefit of all.

In this inaugural process, 100 Fellows have been appointed; included among their number are winners of the Fields Medal (the mathematics equivalent of a Nobel Prize), leading business people, distinguished teachers and academics, science communicators, and pioneers of computing and machine learning. This appointment includes five members of the University of Edinburgh.

Much like Fellows of the other National Academies (Royal Society, Royal Academy of Engineering, British Academy and the Academy of Medical Sciences), the Fellows of the Academy for the Mathematical Sciences have been recognised for being leaders in their fields, through fundamental discoveries, exceptional work in education, or driving the application of mathematics across society as part of our critical national infrastructure.

Fellows will act as leading ambassadors for the Academy, and as key points of contact and connectivity between the mathematical sciences community, the Academy, and the wider world of industry, government, learning and society.

Professor Dame Alison Etheridge DBE FRS, the President of the Academy for Mathematical Sciences, said:

I’m delighted to welcome our inaugural Fellows — individuals of exceptional distinction who collectively advance the mathematical sciences through discovery, leadership, education and real-world application.

Congratulations to Dr Sally Shaw who has been awarded the 2025 Chancellor’s Award: Rising Star.

Chancellor’s Awards

The Chancellor’s Awards are one of the most important ways in which the University recognises current members of the University community who have made outstanding contributions to teaching or research, achieved national and international recognition for their work, or made an outstanding contribution to the University's work in general.

The awards were presented by the Chancellor, Her Royal Highness The Princess Royal, during a gala dinner held this week at the Palace of Holyroodhouse. The Lord Provost, Councillor Robert Aldridge, joined in congratulating the winners.

Rising Star Award

The Rising Star Award honours an early career colleague who has made a significant contribution in their role.

Dr Sally Shaw is a Lecturer in Experimental Particle Physics in the School of Physics and Astronomy. Sally received the Rising Star Chancellor’s Award in recognition of her outstanding reputation in the field of dark matter detection, and her outstanding leadership in both research and in public outreach programmes.

Dark Matter

Sally’s research focusses on the direct detection of dark matter - an elusive substance that comprises 80% of the matter in the universe but remains one of the biggest mysteries in modern science. She is a recognised leader in the field, having delivered world-leading results as the LZ experiment’s Physics Coordinator. Furthermore, she is leading delivery of the largest component of LZ’s scaled-up successor, XLZD, and is one of the UK academics driving the effort to host XLZD in the UK at the Boulby Underground Laboratory. 

Championing inclusion and opportunities in physics

As one of a small number of female academics in her discipline and a first-generation university graduate, Sally has been a driving force in public engagement and equity, diversity and inclusion within the particle physics community and at Edinburgh, with a particular focus on encouraging under-represented groups into physics and engaging schools in remote and deprived areas.

Dr Sally Shaw said:

I feel extremely honoured to have been recognised through this award after a very busy start to my career at the University of Edinburgh. My work would not have been possible without being surrounded by the world-class physicists and amazing professional services staff who have been nothing but welcoming and supportive since I got here.

Scientists have uncovered a previously hidden way that hydrogen molecules can move when subjected to extreme conditions.

Researchers at the Centre for Science at Extreme Conditions (CSEC) have observed a new type of quantum excitation in solid hydrogen, deuterium and the mixture of the two. Their results show that solid hydrogen molecules can only point in certain directions, and that anything in between is forbidden by the rules of quantum mechanics.

Hydrogen and quantum mechanics

The hydrogen molecule (H₂) is one of the simplest systems in quantum mechanics, and along with its well-defined spectroscopic properties, it makes a good textbook example for illustrating key concepts. The fundamental principle of quantum mechanics is that the energy of molecules is only allowed to have discrete values: quantum level. Until now, spectroscopic work detected two types of motion - vibrations and rotations. These are determined using a laser energy to speed up the rotation or vibration and measuring the ratio of the energy of quanta between hydrogen and deuterium. Fundamental quantum mechanics predicts that rotations vary by a factor of 2, vibrations by √2. This is because rotations have only kinetic energy, whereas vibrations have both kinetic and potential energy. 

A predicted but previously unseen excitation

However, a third type of excitation, with changes to potential energy only, was theorised by Professor Ackland. This is based on reorientation of the molecule while the total angular momentum is unchanged, so-called ΔJ = 0 or ‘zero-roton’ transitions where J labels the rotational energy. In a gas or liquid, such transitions are undetectable because there is no energy change to measure. However, when hydrogen enters a high-pressure solid state, the crystal field environment alters its symmetry: again quantum mechanics insists that the molecule orientates in one of a few fixed directions, nothing in between, but now these ΔJ = 0 reorientation transitions involve an energy change which can be detected by Raman Spectroscopy. However, because the energy change is small, the signal is exceptionally difficult to detect and had never been directly captured experimentally. This is despite the fact that the energy change is the same for both deuterium and hydrogen. 

Detecting an exceptionally faint signal

Using a sensitive Raman spectroscopy system, Professor Gregoryanz’s team conducted systematic spectroscopic measurements across a range of pressure and temperature conditions. They studied dense hydrogen, deuterium, and mixtures of the two, unambiguously observing this ‘hidden’ excitation signal for the first time. They found that in the gas and liquid state this excitation has, as theory suggests, zero Raman shift, but in the solid state, the crystal field drives it away from the zero value e.g. ~150 cm−1 at above 100 GPa and 20-45 K for both isotopes. Furthermore, the frequency of the ΔJ = 0 transition exhibits complete isotope independence, representing a novel excitation mode distinct from traditional harmonic oscillators and quantum rotors. The research further revealed the unique behaviour of this excitation during conversion between the different forms of hydrogen (known as ortho-para conversion). These observations provide crucial experimental clues for understanding the evolution of hydrogen's quantum states under extreme conditions.

From prediction to proof

Professor Gregoryanz said: 

We have known that the zero-roton excitation was there for more than 10 years, having observed it in previous work. But working on other effects meant that we never had the opportunity to pursue it. It is now very exciting to finally sort out and understand it – what we once saw as a nuisance turned out to be something fundamental.

Professor Ackland said: 

The prediction of the ΔJ = 0 transition was a central feature of the project, and in retrospect we even observed it in previous experiments: but to prove that the signal is indeed the zero-roton, and not some other effect, required incredibly precise work under extremely challenging experiments. As a theorist, it is thrilling to see the effect finally proven.

This discovery completes the final experimental observation of all allowed types of quantum transition in dense hydrogen, revealing the complete manifestation of Raman selection rules modified by a crystal field. It also provides a unique example showcasing the novel physics emerging in fundamental quantum systems under extreme conditions. 

These results were published in Physical Review Letters, and the work was supported by the EPSRC, ERC, and a range of Chinese Funding agencies.