The source of more than half of all wildfires in the Western US remains unknown, so the US Forest Service has teamed up with computer scientists to create tools that can find answers.
Learn about a recent study that asserts the Andes Mountains in South America as the birthplace of a pathogen that has caused potato blight across the world.
Written with Los Alamos National Laboratory theoretical physicist Ian Tregillis, who is also a science-fiction author of several books, they have derived a mathematical model of the so-called wild cards virus.
The Wild Cards universe is a series of novels created by a consortium of writers including Martin and Tregillis.
Set largely during an alternate history of the US following the Second World War, the series follows events after an extraterrestrial virus, known as the Wild Card virus, has spread worldwide. It mutates human DNA causing profound changes in human physiology and society at large.
The virus follows a fixed statistical distribution of outcomes in that 90% of those infected die, 9% become physically mutated (referred to as “jokers”) and 1% gain superhuman abilities (known as “aces”). Such capabilities include the ability to fly as well as being able to move between dimensions. The stories in the series then follow the individuals that have been impacted by the virus.
Tregillis and Martin have now derived a formula for the viral behaviour of the Wild Card virus. “Like any physicist, I started with back-of-the-envelope estimates, but then I went off the deep end,” notes Tregillis. “Being a theoretician, I couldn’t help but wonder if a simple underlying model might tidy up the canon.”
The model takes into consideration the severity of the changes (for the 10% that don’t instantly die) and the mix of joke/ace traits. After all, those infected can also become cryto-jokers or crypto-aces – undetected cases where individuals have subtle changes or powers – as well as joker-aces, in which a human develops both mutations and superhuman abilities.
The result is a dynamical system in which a carrier’s state vector constantly evolves through the model space — until their “card” turns. At that point the state vector becomes fixed and its permanent location determines the fate of the carrier. “The time-averaged behavior of this system generates the statistical distribution of outcomes,” adds Tregillis.
The purpose of the paper, and the model, is also to provide an exercise in demonstrating how “whimsical” scenarios can be used to explore concepts in physics and mathematics.
“The fictional virus is really just an excuse to justify the world of Wild Cards, the characters who inhabit it, and the plot lines that spin out from their actions,” says Tregillis.
The exact origins of cosmic phenomena known as fast radio bursts (FRBs) are not fully understood, but scientists at the Massachusetts Institute of Technology (MIT) in the US have identified a fresh clue: at least one of these puzzling cosmic discharges got its start very close to the object that emitted it. This result, which is based on measurements of a fast radio burst called FRB 20221022A, puts to rest a long-standing debate about whether FRBs can escape their emitters’ immediate surroundings. The conclusion: they can.
“Competing theories argued that FRBs might instead be generated much farther away in shock waves that propagate far from the central emitting object,” explains astronomer Kenzie Nimmo of MIT’s Kavli Institute for Astrophysics and Space Research. “Our findings show that, at least for this FRB, the emission can escape the intense plasma near a compact object and still be detected on Earth.”
As their name implies, FRBs are brief, intense bursts of radio waves. The first was detected in 2007, and since then astronomers have spotted thousands of others, including some within our own galaxy. They are believed to originate from cataclysmic processes involving compact celestial objects such as neutron stars, and they typically last a few milliseconds. However, astronomers have recently found evidence for bursts a thousand times shorter, further complicating the question of where they come from.
Nimmo and colleagues say they have now conclusively demonstrated that FRB 20221022A, which was detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in 2022, comes from a region only 10 000 km in size. This, they claim, means it must have originated in the highly magnetized region that surrounds a star: the magnetosphere.
“Fairly intuitive” concept
The researchers obtained their result by measuring the FRB’s scintillation, which Nimmo explains is conceptually similar to the twinkling of stars in the night sky. The reason stars twinkle is that because they are so far away, they appear to us as point sources. This means that their apparent brightness is more affected by the Earth’s atmosphere than is the case for planets and other objects that are closer to us and appear larger.
“We applied this same principle to FRBs using plasma in their host galaxy as the ‘scintillation screen’, analogous to Earth’s atmosphere,” Nimmo tells Physics World. “If the plasma causing the scintillation is close to the FRB source, we can use this to infer the apparent size of the FRB emission region.”
According to Nimmo, different models of FRB origins predict very different sizes for this region. “Emissions originating within the magnetized environments of compact objects (for example, magnetospheres) would produce a much smaller apparent size compared to emission generated in distant shocks propagating far from the central object,” she explains. “By constraining the emission region size through scintillation, we can determine which physical model is more likely to explain the observed FRB.”
Challenge to existing models
The idea for the new study, Nimmo says, stemmed from a conversation with another astronomer, Pawan Kumar of the University of Texas at Austin, early last year. “He shared a theoretical result showing how scintillation could be used a ‘probe’ to constrain the size of the FRB emission region, and, by extension, the FRB emission mechanism,” Nimmo says. “This sparked our interest and we began exploring the FRBs discovered by CHIME to search for observational evidence for this phenomenon.”
The researchers say that their study, which is detailed in Nature, shows that at least some FRBs originate from magnetospheric processes near compact objects such as neutron stars. This finding is a challenge for models of conditions in these extreme environments, they say, because if FRB signals can escape the dense plasma expected to exist near such objects, the plasma may be less opaque than previously assumed. Alternatively, unknown factors may be influencing FRB propagation through these regions.
A diagnostic tool
One advantage of studying FRB 20221022A is that it is relatively conventional in terms of its brightness and the duration of its signal (around 2 milliseconds). It does have one special property, however, as discovered by Nimmo’s colleagues at McGill University in Canada: its light is highly polarized. What is more, the pattern of its polarization implies that its emitter must be rotating in a way that is reminiscent of pulsars, which are highly magnetized, rotating neutron stars. This result is reported in a separate paper in Nature.
In Nimmo’s view, the MIT team’s study of this (mostly) conventional FRB establishes scintillation as a “powerful diagnostic tool” for probing FRB emission mechanisms. “By applying this method to a larger sample of FRBs, which we now plan to investigate, future studies could refine our understanding of their underlying physical processes and the diverse environments they occupy.”
When a US research lab accidentally created a sticky, web-like substance, it turned to Peter Parker and comic-book lore for inspiration on what to do next.
In June 1925, a relatively unknown physics postdoc by the name of Werner Heisenberg developed the basic mathematical framework that would be the basis for the first quantum revolution. Heisenberg, who would later win the Nobel Prize for Physics, famously came up with quantum mechanics on a two-week vacation on the tiny island of Helgoland off the coast of Germany, where he had gone to cure a bad bout of hay fever.
Now, a century later, we are on the cusp of a second quantum revolution, with quantum science and technologies growing rapidly across the globe. According to the State of Quantum 2024 report, a total of 33 countries around the world currently have government initiatives in quantum technology, of which more than 20 have national strategies with large-scale funding. The report estimates that up to $50bn in public cash has already been committed.
It’s a fitting tribute, then, that the United Nations (UN) has chosen 2025 to be the International Year of Quantum Science and Technology (IYQ). They hope that the year will raise global awareness of the impact that quantum physics and its applications have already had on our world. The UN also aims to highlight to the global public the myriad potential future applications of quantum technologies and how they could help tackle universal issues – from climate and clean energy to health and infrastructure – while also addressing the UN’s sustainable development goals.
The Institute of Physics (IOP), which publishes Physics World, is one of the IYQ’s six “founding partners” alongside the German (DPG) and American physical societies (APS), SPIE, Optica and the Chinese Optical Society. “The UNESCO International Year of Quantum is a wonderful opportunity to spread the word about quantum research and technology and the transformational opportunities it is opening up” says Tom Grinyer, chief executive of the IOP. “The Institute of Physics is co-ordinating the UK and Irish elements of the year, which mark the 100th anniversary of the first formulation of quantum mechanics, and we are keen to celebrate the milestone, making sure that as many people as possible get the opportunity to find out more about this fascinating area of science and technology,” he adds.
“IYQ provides the opportunity for societies and organizations around the world to come together in marking both the 100-year history of the field, as well as the longer-term real-world impact that quantum science is certain to have for decades to come,” says Tim Smith, head of portfolio development at IOP Publishing. “Quantum science and technology represents one of the most exciting and rapidly developing areas of science today, encompassing the global physical-sciences community in a way that connects scientific wonder with fundamental research, technological innovation, industry, and funding programmes worldwide.”
Taking shape
The official opening ceremony for IYQ takes place on 4–5 February at the UNESCO headquarters in Paris, France, although several countries, including Germany and India, held their own launches in advance of the main event . Working together, the IOP and IOP Publishing have developed a wide array of quantum resources, talks, conferences, festivals and public-themed events planned as a part of the UK’s celebrations for IYQ.
In late February, meanwhile, the Royal Society – the world’s oldest continuously active learned society – will host a two-day quantum conference. Dubbed “Quantum Information”, it will bring together scientists, industry leaders and public-sector stakeholders to discuss the current challenges involved in quantum computing, networks and sensing systems.
The IOP will use the focus this year gives us to continue to make the case for the investment in research and development, and support for physics skills, which will be crucial if we are to fully unlock the economic and social potential of the quantum sector
With the booming quantum marketplace, it’s no surprise that employers are on the hunt for many skilled physicists to join the workforce. And indeed, there is a significant scarcity of skilled quantum professionals for the many roles across industry and academia. Also, with quantum research advancing everything from software and machine learning to materials science and drug discovery, your skills will be transferable across the board.
If you plan to join the quantum workforce, then choosing the right PhD programme, having the right skills for a specific role and managing risk and reward in the emerging quantum industry are all crucial. There are a number of careers events on the IYQ calendar, to learn more about the many career prospects for physicists in the sector. In April, for example, the University of Bristol’s Quantum Engineering Centre for Doctoral Training is hosting a Careers in Quantum event, while the Economist magazine is hosting its annual Commercialising Quantum conference in May.
There will also be a special quantum careers panel discussion, including top speakers from the UK and the US, as part of our newly launched Physics World Live panel discussions in April. This year’s Physics World Careers 2025 guide has a special quantum focus, and there’ll also be a bumper, quantum-themed issue of thePhysics World Briefing in June. The Physics World quantum channel will be regularly updated throughout the year so you don’t miss a thing.
Read all about it
IOP Publishing’s journals will include specially curated content – from a series of Perspectives articles – personal viewpoints from leading quantum scientists – in Quantum Science and Technology. The journal will also be publishing roadmaps in quantum computing, sensing and communication, as well as focus issues on topics such as quantum machine learning and technologies for quantum gravity and thermodynamics in quantum coherent platforms.
“Going right to the core of IOP Publishing’s own historic coverage we’re excited to be celebrating the IYQ through a year-long programme of articles in Physics World and across our journals, that will hopefully show a wide audience just why everyone should care about quantum science and the people behind it,” says Smith.
In this episode of Physics World Stories, we celebrate the 100th anniversary of Werner Heisenberg’s trip to the North Sea island of Helgoland, where he developed the first formulation of quantum theory. Listen to the podcast as we delve into the latest advances in quantum science and technology with three researchers who will be attending a 6-day workshop on Helgoland in June 2025.
Featuring in the episode are: Nathalie De Leon of Princeton University, Ana Maria Rey from the University of Colorado Boulder, and Jack Harris from Yale University, a member of the programme committee. These experts share their insights on the current state of quantum science and technology: discussing the latest developments in quantum sensing, quantum information and quantum computing.
They also reflect on the significance of attending a conference at a location that is so deeply ingrained in the story of quantum mechanics. Talks at the event will span the science and the history of quantum theory, as well as the nature of scientific revolutions.
Physicists in the US, Europe and Korea have produced a long-lasting light-driven magnetic state in an antiferromagnetic material for the first time. While their project started out as a fundamental study, they say the work could have applications for faster and more compact memory and processing devices.
Antiferromagnetic materials are promising candidates for future high-density memory devices. This is because in antiferromagnets, the spins used as the bits or data units flip quickly, at frequencies in the terahertz range. Such rapid spin flips are possible because, by definition, the spins in antiferromagnets align antiparallel to each other, leading to strong interactions among the spins. This is different from ferromagnets, which have parallel electron spins and are used in today’s memory devices such as computer hard drives.
Another advantage is that antiferromagnets display almost no macroscopic magnetization. This means that bits can be packed more densely onto a chip than is the case for the ferromagnets employed in conventional magnetic memory, which do have a net magnetization.
A further attraction is that the values of bits in antiferromagnetic memory devices are generally unaffected by the presence of stray magnetic fields. However, Nuh Gedik of the Massachusetts Institute of Technology (MIT), who led the latest research effort, notes that this robustness can be a double-edged sword: the fact that antiferromagnet spins are insensitive to weak magnetic fields also makes them difficult to control.
Antiferromagnetic state lasts for more than 2.5 milliseconds
In the new work, Gedik and colleagues studied FePS3, which becomes an antiferromagnet below a critical temperature of around 118 K. By applying intense pulses of terahertz-frequency light to this material, they were able to control this transition, placing the material in a metastable magnetic state that lasts for more than 2.5 milliseconds even after the light source is switched off. While such light-induced transitions have been observed before, Gedik notes that they typically only last for picoseconds.
The technique works because the terahertz source stimulates the atoms in the FePS3 at the same frequency at which the atoms collectively vibrate (the resonance frequency). When this happens, Gedik explains that the atomic lattice undergoes a unique form of stretching. This stretching cannot be achieved with external mechanical forces, and it pushes the spins of the atoms out of their magnetically alternating alignment.
The result is a state in which the spin in one direction is larger, transforming the originally antiferromagnetic material into a state with net magnetization. This metastable state becomes increasingly robust as the temperature of the material approaches the antiferromagnetic transition point. That is a sign that critical fluctuations near the phase transition point are a key factor in enhancing both the magnitude and lifetime of the new magnetic state, Gedik says.
A new experimental setup
The team, which includes researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Germany, the University of the Basque Country in Spain, Seoul National University and the Flatiron Institute in New York, wasn’t originally aiming to produce long-lived magnetic states. Instead, its members were investigating nonlinear interactions among low-energy collective modes, such as phonons (vibrations of the atomic lattice) and spin excitations called magnons, in layered magnetic materials like FePS3. It was for this purpose that they developed a new experimental setup capable of generating strong terahertz pulses with a wide spectral bandwidth.
“Since nonlinear interactions are generally weak, we chose a family of materials known for their strong coupling between magnetic spins and phonons,” Gedik says. “We also suspected that, under such intense resonant excitation in these particular materials, something intriguing might occur – and indeed, we discovered a new magnetic state with an exceptionally long lifetime.”
While the researchers’ focus remains on fundamental questions, they say the new findings may enable a “significant step” toward practical applications for ultrafast science. “The antiferromagnetic nature of the material holds great potential for potentially enabling faster and more compact memory and processing devices,” says. Gedik’s MIT colleague Batyr Ilyas. He adds that the observed long lifetime of the induced state means that it can be explored further using conventional experimental probes used in spintronic technologies.
The team’s next step will be to study the nonlinear interactions between phonons and magnons more closely using two-dimensional spectroscopy experiments. “Second, we plan to demonstrate the feasibility of probing this metastable state through electrical transport experiments,” Ilyas tells Physics World. “Finally, we aim to investigate the generalizability of this phenomenon in other materials, particularly those exhibiting enhanced fluctuations near room temperature.”
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