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Destroyers of the world: the physicists who built nuclear weapons

The title of particle physicist Frank Close’s engaging new book, Destroyer of Worlds, refers to Robert Oppenheimer’s famous comment after he witnessed the first detonation of an atomic bomb, known as the Trinity test, in July 1945. Quoting the Hindu scripture Bhagavad Gita, he said “Now I am become death, the destroyer of worlds.” But although Close devotes much space to the Manhattan Project, which Oppenheimer directed between 1942 and 1945, his book has a much wider remit.

Aimed at non-physicist readers with a strong interest in science, though undoubtedly appealing to physicists too, the book seeks to explain the highly complex physics and chemistry that led to the atomic bomb – a term first coined by H G Wells in his 1914 science-fiction novel The World Set Free. It also describes the contributions of numerous gifted scientists to the development of those weapons.

Close draws mainly on numerous published sources from this deeply analysed period, including Richard Rhodes’s seminal 1988 study The Making of the Atomic Bomb. He starts with Wilhelm Röntgen’s discovery of X-rays in 1895, before turning to the discovery of radioactivity by Henri Becquerel in 1896 – described by Close as “the first pointer to nuclear energy [that was] so insignificant that it was almost missed”. Next, he highlights the work on radium by Marie and Pierre Curie in 1898.

After discussing the emergence of nuclear physics, Close goes on to talk about the Allies’ development of the nuclear bomb. A key figure in this history was Enrico Fermi, who abandoned Fascist Italy in 1938 and emigrated to the US, where he worked on the Manhattan Project and built the first nuclear reactor, in Chicago, in 1942.

Fermi showed his legendary ability to estimate a physical phenomenon’s magnitude by shredding a sheet of paper into small pieces and throwing them into the air

Within seconds of seeing Trinity’s blast in the desert in 1945, Fermi showed his legendary ability to estimate a physical phenomenon’s magnitude by shredding a sheet of paper into small pieces and throwing them into the air. The bomb’s shock wave blew this “confetti” (Close’s word) a few metres away. After measuring the exact distance, Fermi immediately estimated that the blast was equivalent to about 10,000 tonnes of TNT. This figure was not far off the 18,000 tonnes determined a week later following a detailed analysis by the project team.

The day after the Trinity test, a group of 70 scientists, led by Leo Szilard, sent a petition to US President Harry Truman, requesting him not to use the bomb against Japan. Albert Einstein agreed with the petition but did not sign it, having been excluded from the Manhattan Project on security grounds (though in 1939 he famously backed the bomb’s development, fearing that Nazi Germany might build its own device). Despite the protests, atomic bombs were dropped on Hiroshima and Nagasaki less than a month later – a decision that Close neither defends nor condemns.

Other key figures in the Manhattan Project were emigrants to the UK, who had fled Germany in the mid-1930s because of Nazi persecution of Jews, and later joined the secret British Tube Alloys bomb project. The best known are probably the nuclear physicists Otto Frisch and Rudolf Peierls, who initially worked together at the University of Birmingham for Tube Alloys before joining the Manhattan Project. They both receive their due from Close.

Oddly, however, he neglects to mention their fellow émigré Franz (Francis) Simon by name, despite acknowledging the importance of his work in demonstrating a technique to separate fissionable uranium-235 from the more stable uranium-238. In 1940 Simon, then working at the Clarendon Laboratory in wartime Oxford, showed that separation could be achieved by gaseous diffusion of uranium hexafluoride through a porous barrier, which he initially demonstrated by hammering his wife’s kitchen sieve flat to make the barrier.

The Manhattan Project set an example for the future of science as a highly collaborative, increasingly international albeit sometimes dangerous adventure

As Close ably documents and explains, numerous individuals and groups eventually ensured the success of the Manhattan Project. In addition to ending the Second World War and preserving freedom against Fascism, there is an argument that it also set an example for the future of science as a highly collaborative, increasingly international albeit sometimes dangerous adventure.

A fusion of minds

Artist's illustration of two minds swapping ideas

Close finishes the book with a shorter discussion of the two decades of Cold War rivalry between scientists from the US and the Soviet Union to develop and test the hydrogen bomb. It features physicists such as Edward Teller and Andrei Sakharov, who led the efforts to build the American “Super Bomb” and the Soviet “Tsar Bomba”, respectively.

The book ends in around 1965, after the 1963 partial test-ban treaty signed by the US, Soviet Union and the UK, preventing further tests of the hydrogen bomb for fear of their likely devastating effects on Earth’s atmosphere. As Close writes, the Tsar Bomba was more powerful than any recorded explosion other than the meteorite impact 65 million years ago that wreaked global change and killed the dinosaurs, which had ruled for 150 million years.

“Within just one per cent of that time, humans have produced nuclear arsenals capable of replicating such levels of destruction,” Close warns. “The explosion of a gigaton weapon would signal the end of history. Its mushroom cloud ascending towards outer space would be humanity’s final vision.”

2025 Allen Lane £25.00hb 321pp

A breakthrough in the hunt for dark matter

Dark matter makes up over 25% of the universe’s mass, holds galaxies together, and is essential to our understanding of cosmic structure. It doesn’t interact with light or other electromagnetic radiation, and is detectable only through its gravitational effects. While astrophysical and cosmological evidence confirms its presence, its true nature remains one of the greatest mysteries in modern physics.

A leading theory suggests that dark matter consists of extremely light, elusive particles called axions. Traditional axion searches rely on narrow-band resonance techniques, which require slow, step-by-step scanning across possible axion masses, making the process time-consuming.

In this study, researchers introduce a new broadband quantum sensing approach using an alkali-²¹Ne spin system, which works like a very sensitive antenna to listen for signals from dark matter. They identify two distinct ways the system behaves under different conditions. At low frequencies, the spin system naturally adjusts itself to cancel out noise or unwanted effects. This self-compensation makes the system stable and sensitive, even without fine-tuning. It’s like a car that automatically balances itself on a bumpy road, you don’t need to steer constantly. At higher frequencies, the system enters a state where the spins of different atoms resonate together. This resonance boosts the signal, making it easier to detect tiny effects caused by dark matter. Like two musical instruments playing in harmony, the combined sound is louder and clearer. This allows researchers to significantly expand the search bandwidth without sacrificing sensitivity.

Concept sketch of the broadband quantum spin sensor used to search for axion-like dark matter: the galactic “axion-wind” drives tiny spin torques (Courtesy: ChangE Collaboration)

Their experiment covers a vast frequency range, from very slow oscillations (0.01 Hz) to very fast ones (1000 Hz), enabling a comprehensive search for axion-like dark matter. They set new constraints on how axions might interact with neutrons and protons. For neutrons, they reached a sensitivity that beats previous astrophysical limits in some frequency ranges. For protons, they achieved the best lab-based constraints in specific frequency bands.

This work not only advances the search for dark matter but also opens new frontiers in atomic physics, quantum sensing, and particle physics, offering a powerful new strategy to explore the invisible fabric of the universe.

Read the full article

Dark matter search with a resonantly-coupled hybrid spin system

Kai Wei et al 2025 Rep. Prog. Phys. 88 057801

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Dark matter local density determination: recent observations and future prospects by Pablo F de Salas and A Widmark (2021)

A step towards bridging gravity and quantum physics

A long-standing challenge in physics has been to integrate gravity into the Standard Model, which successfully describes the electromagnetic, weak, and strong forces. The difficulty lies in the mathematical symmetries: general relativity uses infinite-dimensional space-time symmetries, while the Standard Model relies on compact, finite-dimensional ones, making the two frameworks fundamentally incompatible.

A central question in this context is: is gravity a force? Newtonian mechanics says yes, gravity pulls masses together. Einstein’s relativity says no, it’s the curvature of space-time that guides motion. Quantum field theory suggests gravity may be a force mediated by hypothetical particles called gravitons.

The researchers behind this work propose that gravity can be treated as a gauge interaction, similar to electromagnetism. This approach implies gravity is a force mediated by a field and governed by the same kinds of symmetries as the other fundamental interactions.

They introduce unified gravity, a novel framework that reformulates gravity using the compact symmetries of quantum field theory. Working with an eight-dimensional spinor model, they define a space-time dimension field to recover familiar four-dimensional space-time. By applying four U(1) symmetries, they derive a gauge theory of gravity that mirrors the Standard Model, with the stress-energy-momentum tensor emerging naturally from these symmetries.

Their theory reproduces teleparallel gravity through a special geometric condition and describes gravity in flat Minkowski space-time by another geometric condition, making it compatible with quantum field theory. They develop Feynman rules and show the theory is renormalizable at 1-loop, meaning it handles quantum corrections without mathematical breakdown. Finally, they demonstrate that the theory respects BRST symmetry, which ensures gauge consistency in quantum field theory.

While this remains a mathematical theory, it prompts us to reassess how we conceptualize gravity, not as a curvature of space-time, but as a gauge interaction like the other fundamental forces. If validated experimentally, unified gravity could reshape our understanding of the universe and mark a major turning point in theoretical physics.

Read the full article

Gravity generated by four one-dimensional unitary gauge symmetries and the Standard Model

Mikko Partanen and Jukka Tulkki 2025 Rep. Prog. Phys. 88 057802

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How far are we from the quantum theory of gravity? by R P Woodard (2009)

Leo Cancer Care launches first upright photon therapy system

Leo Cancer Care is a trans-Atlantic company that’s pioneering the development of upright radiotherapy – a totally new take on radiation delivery in which the patient is treated in an upright position and rotated in front of a fixed treatment beam. At this week’s ASTRO 2025 meeting in San Francisco, the company introduced its first upright photon therapy system, named Grace, to an enthusiastic crowd in the ASTRO exhibit hall.

Upright treatments have a host of potential advantages over conventional radiotherapy, where patients typically lie on their back during treatment. Studies have shown that the more natural upright posture could deliver more consistent anatomical positioning and organ stability, as well as enabling more comfortable treatment positions, with patients who have experienced the technology reporting improved comfort and greater patient–therapist connection.

A fixed treatment beam also simplifies system design, reduces space and shielding requirements, and lowers infrastructure costs. And for proton therapy in particular, removing the need for a bulky and expensive gantry could help increase global access to advanced cancer treatments. Indeed, a partnership between Leo Cancer Care and Mevion Medical Systems led to the development of the MEVION S250-FIT, an ultracompact upright proton therapy system that fits inside a linac vault.

Moving on from Leo Cancer Care’s initial focus on proton therapy, the new Grace system will deliver conventional X-ray radiation therapy with patients positioned upright. Grace – named after American computer scientist and US Navy rear admiral Grace Hopper – comprises an upright patient positioning system (with six degrees of freedom and 360° continuous rotation) in front of a stationary 6 MV photon linac.

“Our future innovation, Grace, will take a proven technology, photon therapy, and rethink the way it can be delivered,” Sophie Towe, the company’s director of marketing, tells Physics World. “Upright treatment isn’t just about comfort; it’s about consistency, stability and ultimately accessibility. By integrating advanced CT imaging, faster beam delivery and a more natural patient position, we are opening the door to more adaptive and affordable care. Our goal is to show that innovation in radiotherapy doesn’t always mean bigger or more complex; it can mean smarter and more human.”

The system features a fan-beam CT scanner at the treatment isocentre, enabling planning-quality imaging throughout the entire treatment workflow. It also incorporates a large, ultrafast multileaf collimator that, in combination with the stationary photon beam delivery system, is designed to optimize dose conformity and treatment efficiency.

“Leo Cancer Care is already known for delivering upright particle therapy technology, and over the past few years we have seen a real paradigm shift as a result,” says co-founder and CEO Stephen Towe in a press statement. “Grace represents a return to our original company focus of delivering more cost-effective photon treatments to a global stage without sacrificing on treatment quality. Our technology has always been bold, but we are pioneering with purpose and that purpose is to put the patient truly back at the centre of their treatments.”

The company will install the first pre-commercial Grace systems at healthcare institutions within the Upright Photon Alliance research collaboration, which include Centre Léon Bérard, Cone Health, IHH Healthcare, Mayo Clinic and OncoRay.

NASA criticized over its management of $3.3bn Dragonfly mission to Titan

An internal audit has slammed NASA over its handling of the Dragonfly mission to Saturn’s largest moon, Titan. The drone-like rotorcraft, which is designed to land on and gather samples from Titan, has been hit by a two-year delay, with costs surging by $1bn to $3.3bn. NASA now envisions a launch date of July 2028 with Dragonfly arriving at Titan in 2034.

NASA chose Dragonfly in June 2019 as the next mission under its New Frontiers programme. Managed by the Johns Hopkins University Applied Physics Laboratory, it is a nuclear-powered, car-sized craft with eight rotors. Dragonfly will spend over three years studying potential landing sites before collecting data on Titan’s unique liquid environment and looking for signs that it could support life.

The audit, carried out by NASA’s Inspector General, took no issue with NASA’s tests of the rotors’ performance, which were carried out via simulations. Indeed, the mission team is already planning formal testing of the system to start in January. But the audit criticized NASA for letting Dragonfly’s development “proceed under less than ideal circumstances”, including with a “lower than optimum project cost reserves”.

Its report aims to now avoid those problems affecting future New Horizon missions. Specifically, it calls on Nicky Fox, NASA’s associate administrator for its science mission directorate, to document lessons learned from NASA’s decision to start work on the project before establishing a baseline commitment.

It also says that NASA should maintain adequate levels of “unallocated future expenses” for the project and make sure that “the science community is informed of updates to the expected scope and cadence for future New Frontier missions”. A NASA spokesperson told Physics World that NASA management agrees with the recommendations in the report adding that the agency “will use existing resources to address [them]”.

Antiferromagnets could be better than ferromagnets for some ultrafast, high-density memories

Diagrams showing a memory made from a chiral antiferromagnet — **How it works** On the left is a schematic illustration of memory device consisting of a chiral antiferromagnet Mn₃Sn / nonmagnetic metal heterostructure. On the right is a scanning electron microscope image of the fabricated device with a Mn₃Sn nanodot and a nonmagnetic metal channel. (Courtesy: Yutaro Takeuchi *et al*)

While antiferromagnets show much promise for spintronics applications, they have proved more difficult to control compared to ferromagnets. Researchers in Japan have now succeeded in switching an antiferromagnetic manganese–tin nanodot using electric current pulses as short as 0.1 ns. Their work shows that these materials can be used to make efficient high-speed, high-density, memories that operate at gigahertz frequencies, so outperforming ferromagnets in this range.

In antiferromagnets, spins can flip quickly, potentially reaching frequencies well beyond the gigahertz. Such rapid spin flips are possible because neighbouring spins in antiferromagnets align antiparallel to each other thanks to strong interactions among the spins. This is different from ferromagnets, which have parallel electron spins.

Another of their advantages is that antiferromagnets display almost no macroscopic magnetization, meaning that bits can be potentially packed densely onto a chip. And that is not all: the values of bits in antiferromagnetic memory devices are generally unaffected by the presence of external magnetic fields. However, this insensitivity can be a disadvantage because it makes the bits difficult to control.

Faster than ferromagnets

In the new work, a team led by Shunsuke Fukami of Tohoku University made a nanoscale dot device from the chiral antiferromagnet Mn₃Sn. They were able to rapidly and coherently rotate the antiparallel spins in the material using electric currents with a pulse length of just 0.1 ns at zero magnetic field. This is faster than is possible in any existing ferromagnetic device, they say.

The device is also capable of 1000 error-free switching cycles – a level of reliability not possible in ferromagnets, they add.

This result is possible because, unlike conventional antiferromagnets, Mn_₃Sn exhibits a large change in electrical resistance thanks to its unique symmetry of the internal spin texture, explains Yutaro Takeuchi, who is lead author of a paper describing the study. “This effect provides us with an easy method for electrically detecting (reading out) the antiferromagnetic state. Doing this is usually difficult because antiferromagnets are externally ‘invisible’ (remember, they have zero net magnetization), which means their spin ordering cannot be easily read out.”

Until now, Mn_₃Sn had mainly been studied in bulk samples, but in 2019, Fukami’s group succeeded in growing epitaxial thin films of the material. “This allowed us to perform clear-cut experiments using antiferromagnetic thin films and finally answer the question: can antiferromagnets really outperform their ferromagnetic cousins?” says Takeuchi. “Moreover, in this study, we took on the additional challenge of integrating antiferromagnetic thin films into nanoscale devices.”

New types of devices could be possible

Fukami and colleagues have been working on spintronics using ferromagnets for more than 20 years. “Although the fabrication of antiferromagnets was initially difficult, we finally managed to produce high-quality Mn_₃Sn nanodot devices and demonstrated high-speed and high-efficiency control of the antiferromagnetic state,” Takeuchi tells Physics World. “We would say that our work represents a fusion of our two key strengths: a new method for depositing antiferromagnetic thin films and our conventional core technology in the nanofabrication of magnetic materials.”

As for potential applications, the most likely would be a high-performance non-volatile memory (MRAM), he says. “While MRAM technology is now commercially available, its applications remain limited. By further improving its high-speed and low power consumption, we anticipate a broader range of markets, including data centres and AI chips.”

The research, which is detailed in Science, has also highlighted some dynamical aspects of antiferromagnets not seen before in ferromagnets. “In particular, we found that the rotation frequency of an antiferromagnet can be modulated by an applied current, thanks to the unique dynamical equation it obeys,” explains Yuta Yamane, who did the theoretical modelling part of the study. “This distinct property may open the door to new types of devices, such as frequency-tuneable oscillators, and emerging concepts like probabilistic computing.”

Looking ahead, the team will now focus on improving the readout performance of antiferromagnets and pursuing new functionalities. “Thanks to their unique transport properties, chiral antiferromagnets allow us to detect spin ordering in experimental settings, but the readout performance has still not reached the level of ferromagnets,” says Takeuchi. “A breakthrough will be required to overcome this gap.”

How the slowest experiment in the world became a fast success

Nothing is really known about the origin of the world-famous “pitch-drop experiment” at the School of Physics, Trinity College Dublin. Discovered in the 1980s during a clear-out of dusty cupboards, this curious glass funnel contains a dark, black substance. All we do know is that it was prepared in October 1944 (assuming you trust the writing on it). We don’t know who filled the funnel, with what exactly, or why.

Placed on a shelf at Trinity, the funnel was largely ignored by generations of students passing by. But anyone who looked closely would have seen a drop forming slowly at the bottom of the funnel, preparing to join older drops that had fallen roughly once a decade. Then, in 2013 this ultimate example of “slow science” went viral when a webcam recorded a video of a tear-drop blob of pitch falling into the beaker below.

The video attracted more than two million hits on YouTube (a huge figure back then) and the story was covered on the main Irish evening TV news. We also had a visit from German news magazine Der Spiegel, while Discover named it as one of the top 100 science stories of 2013. As one of us (SH) described in a 2014 Physics World feature, the iconic experiment became “the drop heard round the world”.

Pitching the idea

Inspired by that interest, we decided to create custom-made replicas of the experiment to send to secondary schools across Ireland as an outreach initiative. It formed part of our celebrations of 300 years of physics at Trinity, which dates back to 1724 when the college established the Erasmus Smith’s Professorship in Natural and Experimental Philosophy.

An outreach activity that takes 10 years for anything to happen is obviously never going to work. Technical staff at Trinity’s School of Physics, who initiated the project, therefore experimented for months with different tar samples. Their goal was a material that appears solid but will lead to a falling drop every few months – not every decade.

After hitting upon a special mix of two types of bitumen in just the right proportion, the staff also built a robust experimental set-up consisting of a stand, a funnel and flask to hold any fallen drops. Each was placed on a wooden base and contained inside a glass bell jar. There were also a thermometer and a ruler for data-taking along with a set of instructions.

On 27 November 2024 we held a Zoom call with all participating schools, culminating in the official call to remove the funnel stopper

Over 100 schools – scattered all over Ireland – applied for one of the set-ups, with a total of 37 selected to take part. Most kits were personally hand-delivered to schools, which were also given a video explaining how to unpack and assemble the set-ups. On 27 November 2024 we held a Zoom call with all participating schools, culminating in the official call to remove the funnel stopper. The race was on.

Joining the race

Each school was asked to record the temperature and length of the thread of pitch slowly emerging from the funnel. They were also given a guide to making a time-lapse video of the drop and provided with information about additional experiments to explore the viscosity of other materials.

To process incoming data, we set up a website, maintained by yet another one of our technical staff. It contained interactive graphs showing the increased in drop length for every school, together with the temperature when the measurement was taken. All data were shared between schools.

After about four months, four schools had recorded a pitch drop and we decided to take stock at a half-day event at Trinity in March 2025. Attended by more than 80 pupils aged 12–18 and teachers from 17 schools, we were amazed by how much excitement our initiative had created. It spawned huge levels of engagement, with lots of colourful posters.

By the end of the school year, most had recorded a drop, showing our tar mix had worked well. Some schools had also done experiments testing other viscous materials, such as syrup, honey, ketchup and oil, examining the effect of temperature on flow rate. Others had studied the flow of granular materials, such as salt and seeds. One school had even captured on video the moment their drop fell, although sadly nobody was around to see it in person.

Some schools displayed the kits in their school entrance, others in their trophy cabinet. One group of students appeared on their local radio station; another streamed the set-up live on YouTube. The pitch-drop experiment has been a great way for students to learn basic scientific skills, such as observation, data-taking, data analysis and communication.

As for teachers, the experiment is an innovative way for them to introduce concepts such as viscosity and surface tension. It lets them explore the notion of multiple variables, measurement uncertainty and long-time-scale experiments. Some are now planning future projects on statistical analysis using the publicly available dataset or by observing the pitch drop in a more controlled environment.

Wouldn’t it be great if other physics departments followed our lead?

Cosmic microwave background pioneer George Smoot dies aged 80

George Smoot, who shared the Nobel Prize for Physics in 2006 for his studies of the cosmic microwave background (CMB), died on 18 September at the age of 80. Smoot’s work on the blackbody form and anisotropy of the CMB radiation provided strong evidence that the universe was created in a massive explosion called the Big Bang.

Born in Yukon, Florida on 20 February 1945, Smoot studied mathematics and physics at the Massachusetts Institute of Technology (MIT), graduating with a dual major. He then completed a PhD in particle physics at MIT in 1970.

Smoot then moved to the University of California, Berkeley, and the Lawrence Berkeley National Laboratory, where he began working on the NASA-funded High Altitude Particle Physics Experiment. The instrument was designed to search for particle interactions at higher energies than accelerators could produce at the time.

After devising other balloon-borne detectors to search for antimatter, in 1973 Smoot switched to studying the CMB, which had been discovered by Arno Penzias and Robert Wilson in 1964.

Smoot and colleagues conceived several experiments to detect possible variations in the CMB, which at the time was thought to be isotropic. This included using a differential microwave radiometer (DMR) aboard a Lockheed U-2 plane that could measure differences in temperature as small as one-thousandth of a degree in the microwave radiation between two points.

Smoot then proposed a space-based mission to measure possible anisotropies. The probe eventually became NASA’s Cosmic Background Explorer (COBE) satellite, which went into space in 1989 containing a DMR instrument that Smoot led.

Following two years of observations, in April 1992 the COBE team announced that the CMB still bore the black-body signature, albeit at a much lower temperature (2.7 K) due to the ongoing expansion of the universe. The COBE researchers also announced that they had detected tiny temperature fluctuations – as small as one part in 100 000 – in the CMB.

For the work, Smoot together with John Mather who worked on another instrument aboard COBE, shared the 2006 Nobel Prize for Physics “for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation”.

After COBE, Smoot led another balloon experiment – the Millimeter Anisotropy eXperiment IMaging Array – that refined the measurements of the anisotropies of the CMB.

Smoot also collaborated with the journalist Keay Davidson on the 1993 book Wrinkles in Time, which chronicled efforts to measure variations in the CMB.

Media star

After winning the prize, Smoot continued his studies of the CMB as one of the founders of the European Space Agency’s Planck satellite, which launched in April 2009. He also worked in other areas of cosmology such as the study of gamma-ray bursts.

In 2007 he became founding director of the Berkeley Center for Cosmological Physics, in which he used the money from his Nobel prize as seed cash. Two years later he joined Université Paris-Diderot VII (now known as the Université Paris-Cité) where he founded the Paris Center for Cosmological Physics.

Smoot also made several media appearances throughout his career including playing himself on the hit-TV show The Big Bang Theory and in a TV commercial for Intuit TurboTax. He also appeared in the TV show Are You Smarter Than a 5th Grader? where he bagged the top $1m prize.

Ask me anything: Scott Bolton – ‘It’s exciting to be part of a team that’s seeing how nature works for the first time’

What skills do you use every day in your job?

As a planetary scientist, I use mathematics, physics, geology and atmospheric science. But as the principal investigator of Juno, I also have to manage the Juno team, and interface with politicians, people at NASA headquarters and other administrators. In that capacity, I need to be able to talk about topics at various technical levels, because many of the people I’m speaking with are not actively researching planetary science. I need a broad range of skills, but one of the most important is to be able to recognize when I don’t have the right expertise and need to find someone who can help.

The surface of Jupiter — **Pretty amazing** Hurricane-like spiral wind patterns near Jupiter’s north pole as seen by NASA’s Juno mission, of which Scott Bolton is principal investigator. (Courtesy: NASA/JPL/Caltech SwRIMSSS Gerald Eichstädt, SeánDoran)

What do you like best and least about your job?

I really love being part of a mission that’s discovering new information and new ideas about how the universe works. It’s exciting to be at the edge of something, where you are part of a team that’s seeing an image or an aspect of how nature works for the first time. The discovery element is truly inspirational. I also love seeing how a mixture of scientists with different expertise, skills and backgrounds can come together to understand something new. Watching that process unfold is very exciting to me.

Some tasks I like least are related to budget exercises, administrative tasks and documentation. Some government rules and regulations can be quite taxing and require a lot of time to ensure forms and documents are completed correctly. Occasionally, an urgent action item will appear requiring an immediate response and having to drop current work to fit in a new task. As a result, my normal work gets delayed, and this can be frustrating. I consider one of my main jobs to shelter the team from these extraneous tasks so they can get their work done.

What do you know today that you wish you’d known at the start of your career?

The most important thing I know now is that if you really believe in something, you should stick to it. You should not give up. You should keep trying, keep working at it, and find people who can collaborate with you to make it happen. Early on, I didn’t realize how important it was to combine forces with people who complemented my skills in order to achieve goals.

The other thing I wish I had known is that taking time to figure out the best way to approach a challenge, question or problem is beneficial to achieving one’s goals. That was a very valuable lesson to learn. We should resist the temptation to rush into finding the answer – instead, it’s worthwhile to take the time to think about the question and develop an approach.

Be a part of our quantum celebration

Regular readers of Physics World will know that the UN chose 2025 to be the International Year of Quantum Science and Technology (IYQ). With a global diary of events, conferences, talks, workshops and more, its aim is to raise awareness of the impact of quantum physics and its myriad future applications, from healthcare and energy to infrastructure and optimization.

With the Institute of Physics (IOP) being one of the IYQ’s six founding members, we have already seen a packed agenda – including the UK’s opening meeting hosted by the Royal Society in February; a week-long parliamentary exhibition on quantum run by the IOP in June; plus numerous hackathons and careers events. It has been a very busy year.

As the IYQ comes to a close, the UK is giving it a worthy send-off with an entire Quantum Week on 3–7 November. The IOP and the National Physical Laboratory will host conferences and public events, including a talk on “A new quantum world: ‘spooky’ physics to tech revolution” by quantum scientist and TV presenter Jim Al-Khalili.

The highlight of the week for quantum physicists based in the UK will be the IOP’s two-day conference – Quantum Science and Technology: The First 100 Years; Our Quantum Future – at the Royal Institution in London. Day one, organized by the IOP’s History of Physics group, will look back on the first 100 years of quantum mechanics. Speakers will revisit foundational breakthroughs, while charting the evolution of quantum theory, from its early abstract framework to the main pillar it forms in modern physics. Day two – led by the IOP’s quantum Business Innovation and Growth group – will look to the future of quantum tech and its expanding role in society, as quantum computing, sensing and communications become a part of our world.

Despite us celebrating a century of quantum advances, it’s interesting to note that most physicists are still undecided on some of the very foundational aspects of quantum theory. Even 100 years on, we cannot agree on which interpretation of quantum mechanics holds strong; whether the wavefunction is merely a mathematical tool or a true representation of reality; or the effects of an observer on a quantum state.

Indeed, some of the biggest open questions in physics – where exactly is the boundary between the quantum and the classical world; and how do we reconcile gravity and quantum mechanics – lie at the very heart of these conundrums. As we all gather at the IOP’s conference, to look back and ahead, perhaps some answers to these puzzles will become apparent.

Be sure to register for the event as soon as possible so that you are in the room as we perhaps crack the quantum code to our universe.

This article forms part of Physics World‘s contribution to the 2025 International Year of Quantum Science and Technology (IYQ), which aims to raise global awareness of quantum physics and its applications.

Stayed tuned to Physics World and our international partners throughout the year for more coverage of the IYQ.

Find out more on our quantum channel.

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