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Ask me anything: Catherine Phipps – ‘Seeing an aircraft take off and knowing you contributed to the engine design is an amazing feeling’

Catherine Phipps
Talented mind As an engineer at Rolls-Royce in Derby, UK, Catherine Phipps tests how aircraft-engine components behave in extreme conditions. (Courtesy: Catherine Phipps)

What skills do you use every day in your job?

I originally joined Rolls-Royce to use my physics skills in an engineering environment and see them applied in the real world. My plan was to work in the materials department, thinking that would align with my degree. But after completing the graduate training scheme, I chose to join the mechanical-integrity team working on demonstrator engines. A few years later, I moved to Berlin to focus on small engines for civil aerospace before returning to Derby in the UK, where I’m now a mechanical integrity engineer working on large civil engines.

A large part of my job involves understanding how materials behave in extreme conditions, such as high temperature or extreme stress. I might, for example, run simulations to see how long a new component will last or if it will corrode.

I’ll also design programmes to test how components behave when the engine runs in a particular way. The results of these tests are then fed back into the models to validate predictions and improve the simulations. Statistical analysis skills are vital too, as is the ability to make rapid judgements. Above all, I need to consider and understand any safety implications and consider what might happen if the component fails.

It’s a team role, working alongside people from numerous other disciplines such as aerodynamics, fluid mechanics and materials, and everyone brings their own skills. We need to make sure our designs are cost-effective, meet weight targets, and can be manufactured consistently and to the right standard. It’s immensely challenging work, which means I need to collaborate, communicate and – where acceptable – compromise.

What do you like least and best about your job?

Best has to be the people. It’s inspiring and motivating to work day in, day out in an international environment with talented, innovative and dedicated colleagues from varied backgrounds and with different life experiences. Sharing knowledge and coaching younger members of the team is also rewarding. Plus, seeing an aircraft take off and knowing you contributed to the engine design is an amazing feeling.

I did have a seven-year career break to have children, after which I was shocked at how much my colleagues had progressed. I felt in awe and inadequate. It was challenging to return, but everyone assured me the laws of physics hadn’t changed and I soon got back up to speed. The hardest time for me, though, was working from home during COVID-19. Meetings continued online, but I missed the chance conversations with colleagues where we’d run ideas past each other and I’d learn useful information. I felt siloed and it was hard to share knowledge. The line between work and home was blurred and it was always tempting to leave the laptop on and “just finish something” after dinner.

What do you know today you wish you knew when you were starting your career?

First, don’t think you always have to know the answer and don’t be afraid to ask questions. You won’t look stupid and you’ll learn from the responses. When you start working, it’s easy to think you should know everything, but I’m still learning and questioning all these years later. New ideas and perspectives are always valuable, so stay curious and keep wondering “Why?” and “What if?”. You may unlock something new. Second, just because you start on one route, don’t think you can’t do something different. Your career will probably span several decades so when new opportunities arise, don’t be afraid to take them.

The post Ask me anything: Catherine Phipps – ‘Seeing an aircraft take off and knowing you contributed to the engine design is an amazing feeling’ appeared first on Physics World.

Peter Higgs didn’t like talking about himself. Here’s what he told us about CERN, collaboration and his career

You’re best known for the boson that bears your name, but do you still feel uncomfortable, as you’ve expressed in the past, in having your name attached to it?

Well, I feel more comfortable with my name attached to the boson than having my name attached to anything else in that theory – simply because, of the half-dozen people who were involved in the theory at the time, around 1964, I was the only one who drew attention to its existence. I mean it wasn’t that I in any way invented it [the Higgs boson] as part of the theory, but I pointed out it was there as a result of having had the first version of my paper rejected.

It went to Physics Letters – the editor in Geneva apparently passed it along the corridor for somebody to referee, and they didn’t see what the point was. So it got sent back to me and I was annoyed and thought “Well, I’d better extend it in some way to give some indication of the consequences of theorising in this way.” And that’s when I drew attention to its existence. [Higgs’ paper “Broken symmetries and the masses of gauge bosons” eventually appeared in the 19 October 1964 edition of Physical Review Letters (13 508) – see “Spontaneous symmetry breaking explained” box.]

Who else, apart from you, deserves credit for that idea?

If you’re talking about the whole theoretical structure, it certainly involves six people, who shared the Sakurai prize in 2010. That’s [Robert] Brout, [François] Englert, myself, [Gerald] Guralnik, [Carl] Hagen and [Tom] Kibble. But there were other people involved earlier to some extent – and the person who I think is still slightly aggrieved about it is Phil Anderson, the condensed-matter theorist, who said he knew it all already [laughs].

When you suggested that spontaneous symmetry breaking could be how particle mass is generated, did you have any inkling of how significant that work was going to be?

Well, I felt the result was important, but I want to just make a small correction. The person who first showed how to generate mass from spontaneous symmetry breaking was [Yoichiro] Nambu four years earlier (1960 Phys. Rev. 117 648). He wrote down models inspired by superconductivity theory, in which fermions acquired mass from a Lagrangian field theory in which they appeared to be massless at the beginning. Since matter is built from fermions, he’s the man who was really responsible for this way of giving mass to the fundamental fermions of matter.

Of course, he didn’t know about quarks at the time, so he wrote a model in which a proton and neutron were elementary, which isn’t right. But the idea was basically there and what Brout, Englert, I and others did was to fill in the gap in Nambu’s theory – the gap being the lack of a “gauge field”. Nambu hadn’t put it into his models and, as a consequence, he had predicted massless spin-0 particle – the so-called Goldstone bosons – and the six of us [showed] how you change a massless spin-1 particle into a massive spin-1 particle as in the electroweak theory, which was the successful application of it.

Was your work on symmetry breaking and mass generation the most important thing you’ve done in your career – or has there been other work that you’ve been equally proud of?

I don’t think I’ve ever done anything that has been of that much importance, no. I mean that was quite a surprise to me that I did it.

Spontaneous symmetry breaking explained

Two hands holding a plastic ruler
(Courtesy: Shutterstock/Africa Studio)

Imagine holding a ruler at either end and bending it until it buckles either to the left or right, writes Claire Malone. This is an example of “spontaneous symmetry breaking”. In 1962 Jeffrey Goldstone, a theoretical physicist who was then at the University of Cambridge in the UK, predicted that the symmetry of a system being spontaneously broken in this way would lead to the existence of massless, force-carrying particles, now known as Goldstone bosons.

At the time, no suitable candidates for these massless particles had been observed. Then, in 1964 Peter Higgs published a paper in Physics Letters (12 132) proposing a novel idea – that Goldstone bosons don’t necessarily occur when a symmetry is spontaneously broken. Instead, they could be reinterpreted as an additional quantum (polarization) state of a force-carrying particle. The leftover terms in the equations would represent a massive particle, later known as the Higgs boson, avoiding the need for a massless unobserved particle.

Higgs further developed these ideas in a subsequent paper, which outlined what would eventually be recognized as “the Higgs model”. This paper was initially rejected by Physics Letters, judged to have no obvious relevance to physics. Upon receiving this news, Higgs revised the paper, referring to the work of the theorist Philip Anderson, who had been researching a similar mechanism occurring in semiconductors.

In the updated paper, which Higgs sent to Physical Review Letters, Higgs extended Anderson’s theoretical framework to take relativity theory into account. He also highlighted the possibility of a massive spin-zero boson that had been alluded to in an article by Francois Englert and Robert Brout (Phys. Rev. Lett. 13 321). It was published on 31 August 1964 – the same day that Higgs’ paper was received. With this addition, the paper was accepted and published on 19 October 1964 (Phys. Rev. Lett. 13 508).

Higgs’ 1964 work set the stage for the formulation of the Standard Model, by providing a mechanism by which particles in such a model can have the masses we observe.

Claire Malone, who has a PhD in high-energy physics from the University of Cambridge, is a science journalist based in London and a contributing columnist for Physics World, www.drclairemalone.com

There’s been a lot of awareness in the media of work at CERN. Do you think that’s helped in bringing physics to a wider audience?

It certainly has. I commented yesterday after visiting Cotham School, where I was a pupil in Bristol in wartime, that there would have been no such reaction to some experimental results in particle physics back in those days. The popular awareness of what’s going in that field recently has increased tremendously and I think the CERN publicity machine in particular has been responsible for that.

I’ve been a little bit unhappy about the way they’ve done it, in the sense that I think they’ve placed too much emphasis on this one particle [the Higgs boson]. The risk has been that if and when they’ve convinced themselves they’ve got it, some people will say “Well, now we can shut the machine down. It’s expensive and we don’t need it anymore.” I don’t think [CERN] have done as much as they should to give the wider context of what they’re doing. Maybe they’re putting that right now.

With the spotlight on the Large Hadron Collider (LHC), do you find that other parts of physics have been unfairly overlooked by the focus on particle physics?

There’s always a danger of that happening, I suppose. Yesterday I was taken to meet a sixth-form class at Cotham and the teacher asked me [whether] I would encourage people to go into physics after school. And I said “Well, yes.” But I don’t mean just my own kind of physics – it’s a training which equips you to do all sorts of different things, some of which you may not think of as being physics at all [but] which are equally important.

Looking beyond particle physics, what other areas of physics are you personally interested in?

Well at the beginning, before I went into particle physics, my PhD at King’s College London was in what was called molecular physics because I was a physics graduate. It would have been called theoretical chemistry if I had been a chemistry graduate. So I’ve had a residual interest in that – [in fact] that was where I learned a lot about symmetry and the mathematics of symmetry in relation to the behaviour of symmetric molecules of various sorts.

You still sound pretty interested and excited about developments in physics?

Yes, after my work in the 1960s, I got involved again later in supersymmetry. That was the development I found exciting at the sort of basic theoretical level [but] I gave that up at the time because I was too old. The people who really understood the mathematical background and could produce results quickly where probably 30 years younger than me, and I couldn’t keep up.

Another thing which I found very interesting in later years – I suppose starting from around the late 1980s – was the development of quantum cryptography and quantum computing. And I got interested to the extent of supervising final-year student projects in this area. It was connected with the interest I’d had previously in the verification of the Einstein–Podolsky–Rosen business as a result of advances in the development of reliable photon counting in [Alain] Aspect’s experiments.

If the boson that bears your name is found, what’s the next big challenge in physics after that?

Well, of course there are remaining challenges in particle physics because supersymmetry is still just a nice idea. Sticking to that field, which I know best, it’s very hard to see [how] further unification can be done including gravity without going along that route. I’m not sure whether super strings are necessary.

Peter Higgs with François Englert at CERN
Spirit of collaboration Shown here in the CERN auditorium with François Englert on 4 July 2012 when the discovery of the Higgs boson was announced, Peter Higgs (right) was always at pains to stress the contributions of others to particle theory. (Courtesy: CERN/Maximilien Brice)

Today’s particle physics is dominated by huge international collaborations. Do you think that’s destroying originality and initiative of individual physicists?

I don’t know whether it is. All I can say is that I find it hard to imagine surviving in a big team like that. I find it hard to know quite how talent is recognized when it’s such a big collaborative effort. But somehow it still happens I think.

The Higgs boson is sometimes dubbed “the God particle”. Do you think it deserves that name?

I was really rather annoyed about that book [Leon Lederman’s The God Particle, published in 1993] and I think I’m not the only one. I mean it was one of Lederman’s little jokes and I think it’s rather backfired. I’m sure you know the story, which I think he tells in his second edition, which is that he wanted to title his book That Goddam Particle because it was so hard to discover. His editor didn’t like it, so he said “Oh alright, The God Particle” and his editor accepted it.

But a lot of people, I think, don’t find that funny. And when it’s taken too seriously by people who don’t really understand the context of the joke, it does cease to be funny. You know, I’ve seen comments from theologians about it, which really shouldn’t happen.

If you were a student again today, would you still study physics or would something else attract you in another discipline?

It’s hard to know. I mean looking back, one of the features of my education at Cotham School was that science meant mathematics, physics and chemistry. There was no biology on offer. At that stage I thought of biology as a horribly complicated problem, which was really too ill-defined to go into.

But then, as a student at King’s College, I worked – at least as a postgraduate – along the corridor from Maurice Wilkins and Rosalind Franklin and I began to understand that biology was opening up because of the applications of the techniques of physics. And now it’s a very different story. I don’t know how I would choose, if I got the choice again with that sort of knowledge of how biology works at a very fundamental level. [But] I might go for quite a different way.

We talked about the God particle earlier on: do you have any particular religious views?

I don’t, no.

You are agnostic or atheist?

Yes. I mean I don’t believe anyway. I’m a sceptic.

Going back to the boson that bears your name, do you know how exactly that name came about or who’s responsible for it?

Oh, the Higgs boson? Well, the really embarrassing thing was what happened at the 1972 International Conference on High Energy Physics at Fermilab. A colleague of mine, Ken Peach, came back from that and he ran into me in the [Edinburgh] university staff club and said: “Peter, you’re famous!”

And when I discovered what had happened, I was quite embarrassed. I’d met [the Korean-born theorist] Ben Lee – then a theorist at Fermilab – years before at a conference in Rochester organized by Robert Marshak. He’d been interested in what I and others had done and been co-author of a short paper in Physical Review Letters, which preceded mine in 1964 when the debate was going on about whether there was a way out of this Goldstone theorem.

So he was interested in this area and he got hold of me at a sort of party, where I was standing with a plate of food in one hand and a glass of wine in the other and interrogated me about what I had done. I was not really prepared with all my references to other people’s work. So he got my side of the story. [In his role] as a rapporteur at the conference, he should have done a bit more work to find out about the other work at the time. But all the other people were just relegated to a footnote.

He talked about “the Higgs mechanism” and “the Higgs boson” – well, he said “the Higgs meson” at the time because in 1972, the nomenclature hadn’t been clearly defined about what was a meson and what was just another kind of boson. And he had pinned my name on everything to the exclusion of other people, and particularly Brout and Englert were upset about it – understandably.

It took some time to clear up. Well, I don’t know whether it’s ever been cleared up that the situation was much more complicated. Later I acknowledged that maybe my name might be attached to the boson because I was the only one of the six people who’d actually drawn attention to the thing. So that’s more reason for my name than the others perhaps. But everything else was definitely, you know, something which had been shared among as many as six or more people.

It settled down to being called the Higgs boson when the experimentalists were alerted to the need to look for it. That happened in 1975/76 at the time LEP [the Large Electron–Positron collider] was being planned [at CERN] and the paper [Nuc. Phys. B 106 292] by John Ellis and two others [Mary Gaillard and Dimitri Nanopoulos] came out. That was the phenomenology of the Higgs boson. And of course that was a very tentative paper, which said “We can’t tell you much about it, but keep your eyes open for it when you’re doing other things.”

So by about the mid-1970s, the Higgs mechanism and the Higgs field were in common use as terms?

They were in common use. But you know, I would only accept sole responsibility for drawing attention to the particle. The Higgs field was already in papers of Nambu and [the theorist Jeffrey] Goldstone. Most of the stuff was already done by other people.

What’s the best analogy that you’ve ever heard for the Higgs boson?

Well, the one that’s used a lot, which I object to least, is the one used by [the University College London physicist] David Miller, which won him his bottle of champagne from William Waldegrave (see “Peter Higgs’ favourite analogy for the Higgs boson” box).

I object to that least because moving through a crowded room, well – unless it’s extremely crowded – I don’t lose energy much. I zigzag. So my mean velocity in the forward direction is reduced, but that’s all. It’s not a dissipative process. But I do object when people draw an analogy with dragging something through treacle. That’s misleading. That’s a dissipative process and this isn’t.

Peter Higgs’ favourite analogy for the Higgs boson

Colourful large crowd of people
(Courtesy: iStock/baona)

In 1993, amid concerns over the rising cost of Britain’s membership of CERN, the UK’s then science minister William Waldegrave, who was a historian by training, invited people to explain the Higgs boson to him on just an A4 sheet of paper. Waldegrave issued his challenge at that year’s annual congress of the Institute of Physics in Brighton, offering a bottle of vintage champagne at his own expense to the best entry (Physics World May 1993 p8). He told participants that University of Bristol theorist Michael Berry, who lived in his parliamentary constituency, would help judge entries.

“Waldegrave’s declaration came as a complete surprise to me – and slightly embarrassing because sitting next to me was Tom Kibble, who knew vastly more than me,” Berry recalls. “I received about 100 entries, selected five, and sent them to Waldegrave, who replied that he couldn’t assess them. Whether he was too busy or unable, I don’t remember but he said he would give a bottle of champagne to each of them.” The champagne was presented to the winners at the 1993 Keele meeting of the British Association for the Advancement of Science, at which Berry was physics president.

The mostly widely known entry – and the one Peter Higgs favoured – came from David Miller, a physicist at University College London (Physics World September 1993 p27). He envisaged the Higgs field as a crowd of political party workers at a cocktail party. When an ex-prime minister crosses the room, the workers cluster excitedly around her, giving her greater mass than normal, which is the Higgs mechanism. If a rumour enters the room, the workers gather together to hear the gossip, which then travels across the room, with the clustering being the Higgs boson. Miller received a bottle of Veuve Cliquot 1985 champagne for his efforts. It was drunk long ago.

Thank you so much Peter for your time.

You’re welcome.

The post Peter Higgs didn’t like talking about himself. Here’s what he told us about CERN, collaboration and his career appeared first on Physics World.

Silverstone racetrack hosts Institute of Physics summer festival

The 2024 summer festival of the Institute of Physics (IOP), which publishes Physics World, took place on 5 June at Silverstone racetrack, the home of the British Grand Prix and MotoGP.

Entitled “A celebration of physics: on the road to a sustainable world”, the event was held to celebrate the achievements of the IOP’s 2023 award winners and to recognize the work of the IOP’s members.

The day was opened by IOP chief executive Tom Grinyer, who discussed the IOP’s new five-year strategy and outlined its efforts to get science on the agenda during the UK’s general-election campaign.

Over 150 local school children heard University of Surrey physicist Elizabeth Cunningham, the IOP’s vice-president for membership, speak about the many career opportunities on offer for physicists.

Current IOP president Keith Burnett handed out medals and prizes to more than 40 of the 2023 award winners before speaking about his career, the IOP’s new strategy, and its new Physics Inclusion Award.

Mark Richards, a new honorary fellow of the IOP, spoke about his research career as a spectroscopist and his efforts as a Black physicist to improve diversity in physics.

Laura Tobin from ITV’s Good Morning Britain, who studied physics and meteorology, talked about her career as a TV weather broadcaster and her book Everyday Ways to Save the Planet, which offers practical ways to deal with climate change.

Katherine Skipper talking to Hannah Stern at the IOP Summer Festival
In conversation Katherine Skipper talking to Hannah Stern (right). (Courtesy: Jo Allen)

Liv Davies from IOP Publishing spoke about the impact of AI on research integrity, while Physics World features editor Katherine Skipper interviewed Hannah Stern, who won the Henry Moseley medal and prize for her work on novel magneto-optic materials.

There were also talks from James Davies from the UK Atomic Energy Authority about fusion; James Binney (winner of the Isaac Newton Medal) about his studies of galaxies; and David Homfray, chief technology officer at Space Solar, which wants to beam sunlight to Earth to generate electricity.

Science writer Kit Chapman, author of the book Racing Green: How Motorsport Science Can Save the World, discussed how technology from racing can make the world cleaner and safer.

Alongside the main stage was an exhibition of companies and organizations ranging from British Airways to Quantum Gas Lasers, while delegates were able to enjoy a Formula 1 VR simulator and sitting in a replica of 1989 Batmobile.

Among the many people I personally bumped into were Clare Harvey, chief executive of the Ogden Trust, which promotes the teaching and learning of physics, and Hugh Deighton, chair of the IOP’s history of physics group, which has some seriously in-depth newsletters on offer. Sadly, Hollywood’s Brad Pitt, who happened to be filming his new movie at Silverstone, was unavailable.

The post Silverstone racetrack hosts Institute of Physics summer festival appeared first on Physics World.

Ask me anything: Daniel Hook – ‘The skills I learned as a researcher are applicable and helpful in any walk of life’

What skills do you use every day in your job?

As the chief executive officer (CEO) of Digital Science – a company that improves the information and software tools for all stakeholders in the research ecosystem – I use a variety of skills every day. Many of these are exactly what most people would expect: managing people, reading financial statements – all the usual CEO activities. Thankfully for all concerned, I don’t programme anymore. It’s more than a decade since my code was in a production environment.

However, perhaps surprisingly to some, I do a lot of data analysis. Digital Science’s core strength is our passion for understanding the research world as a route to offering better tools. For me, that means looking at what research is trending, understanding collaboration patterns, and gaining insight into how the scholarly record is changing. Not only are the data completely fascinating, but they are also the start of so many interesting discussions.

What do you like best and least about your job?

Let’s start with what I like least – which is travel, specifically the jet lag. While I do love spending time in different cultures, meeting people and seeing the beautiful nature and architecture in the places that I’m fortunate to visit, I find the jet lag to be very difficult and I’m constantly worried about my carbon footprint.

Last year I managed to do almost every trip in Europe by train and felt very good about it. But trips to Australia, New Zealand, Japan and the US still managed to make their way into my diary. This is somewhere I’m hoping that hybrid meetings find their feet soon.

As for what I like best about my job – that’s easy.  Not only do I work with the most talented, kindest and most passionate team, but we also serve those who are the positive agents of change in our world.

What do you know today that you wish you knew when you were starting out in your career?

Like many people who started off working toward a research career, I defined my success very narrowly – specifically, in terms of being successful in a classically defined research setting. However, the skills that I learned as a researcher are all generally applicable and helpful skills in any walk of life.

They include having an entrepreneurial spirit, a willingness to try to solve a problem, the capacity to work hard and focus on that problem, and not give up when you don’t find a solution with the first approach that you take. Success looks different for everyone and the problems that we contribute to solving, in any context, have the capacity to make people’s lives better.

So, sometimes it’s not good to “buy in” to what we’re so often taught success should look like.

The post Ask me anything: Daniel Hook – ‘The skills I learned as a researcher are applicable and helpful in any walk of life’ appeared first on Physics World.

What’s hot in particle and nuclear physics? Find out in the latest Physics World Briefing

Cover of the 2024 Physics World Particle & Nuclear Briefing
Stay tuned The first Physics World Particle and Nuclear Briefing is out now.

From the Higgs boson at CERN to nuclear reactions inside stars, who doesn’t love particle and nuclear physics?

There’s so much exciting work going on in both fields, which is why we’re bringing you this new Physics World Particle & Nuclear Briefing.

The 30-page, free-to-read digital magazine contains the best of our recent coverage in the two areas, including – of course – plenty on CERN, which is celebrating its 70th anniversary this year.

In addition to former CERN science communicator Achintya Rao looking back at the famous day in 2012 when the lab announced the discovery of the Higgs boson, there’s an interview with Freya Blekman, who talks about the joy of a career in physics as part of the CMS experiment at the Large Hadron Collider.

You can also find out how CERN’s Quantum Technology Initiative is encouraging collaboration between the high-energy physics and quantum tech communities.

But it's not all about CERN. Over in the US, there are in-depth interviews with Lia Merminga, the physicist who's current director of the Fermi National Accelerator Laboratory, and with Mike Witherell, who’s head of the Lawrence Berkeley National Laboratory.

Looking to the future, we’ve included an analysis of the influential “P5” report into the future of US particle physics, which recently called for the construction of a muon collider. Physics World also talks to Ambrogio Fasoli – the new head of EUROfusion, who says that Europe must ramp up its efforts to build a demonstration fusion reactor.

And with our pick of the best recent news and research updates, the new Physics World Particle & Nuclear Briefing really is the place for you to start.

If that's not enough, do keep checking our particle and nuclear channel on the Physics World website for regular updates in the two fields.

The post What’s hot in particle and nuclear physics? Find out in the latest <em>Physics World Briefing</em> appeared first on Physics World.

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