Hello, and welcome to the Physics World weekly podcast. I'm Hamish Johnston. In this episode, we explore how pictures can be used to teach the fundamentals of quantum physics to everyone. But first, a message from IOP publishing, which brings you Physics World and also publishes an impressive range of scholarly journals, conference proceedings, and ebooks. You can download the book, The Ringed Planet second edition, for free for a limited time only at i0ppublishing.org/theringedplanet free book.
The book is a must read on Saturn and the Cassini mission. And you can also check out the updated and expanded third edition by Joshua Colwell, which is hot off the press. You can find it with all of I OPP's ebooks at i0ppublishing.org/publications/ebooks. And while you're browsing titles, remember that you can always read the first chapters of all I OPP ebooks for free. And I'll include both of those URLs in the notes for this episode.
Today, quantum physics is enjoying a renaissance in science and technology. After decades of speculation, quantum computers are now real things, and quantum sensors are being used in a wide range of applications from underground surveying to measuring brain activity. As the technologies we use become more quantum in nature, it follows that everyone should have a basic understanding of quantum physics, something that today remains mostly the preserve of scientists, engineers, and mathematicians.
To explore how quantum physics can be taught to everyone, I'm joined by Arjun Dovin, Alex Kissinger, and Bob Kuka, who are all based in The UK. Bob is chief scientist at Quantinium, which develops quantum computing hardware and software. Alex is associate professor of quantum computing at the University of Oxford, and Arjun is studying mathematics at the University of Durham. Alex and Bob have developed a way of teaching quantum physics using diagrams.
And in 2023, Oxford and Quantinium joined forces to use this method in a pilot summer program for fifteen to seventeen year olds, and Arjun was one of their students. Hi, Alex, Arjun, and Bob. Welcome to the podcast. So, Bob, could can we start off by, having you explain why the time has come to teach quantum physics to everyone, not just physics students?
So what's happening at the moment or is about to happen, and people should have noticed this, I guess, if they're listening to a podcast like this, is that we're, like, on the verge of a a technological revolution, which is gonna be the quantum revolution. Some people call this the second quantum revolution after what happened, of course, in the beginning of the previous century. And and so this is gonna impact, many aspects of our life,
very soon for many people. And so you want some form of inclusivity with respect to people knowing what is going on. So it's usually, quantum is conceived as something that you need a university degree and and or a or a PhD to understand. And now we have the tool at hand for, like, a much broader, like, portion of society, even not everybody, because we like to say quantum for everyone, can actually understand quantum and grasp the basic concepts.
That's basically what this podcast is about. Some work, Alex and I did, some experiments with it a little bit back to show that what I'm claiming here is actually true. Now inclusivity means, for example, that people students can learn this at high school or later, but also that people in countries which are usually not that much subject to to technological things, like in Africa, also can be part of this gig. And maybe that's something that's gonna come up later in this in in
this chat. I actually believe that some non Western countries actually have an advantage now to to be inclusive. Now another thing is I mean, I was asked to speak at the US capital because this is case of workforce preparation, like making the workforce much bigger for quantum, which is also necessary. And I would also bring in accountability here because of what we are seeing now with AIs. Nobody has a clue what's going on.
And that's not very healthy, especially if only a few people in the world with a lot of billions can make all the decisions while nobody else knows what's going on. So that's the last one. And, I mean, as as a last command, I would say, quantum comes with a radical shift in worldview, in the way we perceive the world, not in contrast to classical physics, but I would actually take this back two thousand five hundred years to the presocratics. But maybe we can talk about that later.
I see. And and, Bob, this is, I mean, this isn't just a concept for you. You, you have spent a lot of time, trying to come up with ways of of, I suppose, teaching quantum physics to to non physicists, to the to the general public. And and one thing that you've done is you've coauthored a book called Quantum in Pictures. And that takes a a graphical approach with no sort of conventional equations to teach quantum physics to a wide audience.
Can you describe the the approach that you've taken in the book? I mean, this was a very long process. And, so so my background historically, going back to the nineteen nineties, is is kind of more with a new language for quantum over or a new mathematics
for quantum. And this goes back to a question of John von Neumann post in nineteen thirty nineteen thirty five when he based John von Neumann is the father of the usual quantum mechanical, formalism, Hilbert space, also being the father of the computers we're using here to talk, by the way. And he denounced his own quantum mechanical formulas in 1935. So I came from a culture, a community where we try to come up with something new.
And then I was very lucky to actually with a background as a physicist to end up in a computer science department in Oxford where where Alex now is a is a professor. I used to be a professor there. And then new ways of viewing at the world came from computer science, which are more about thinking of things in terms of processes and thinking of things in how stuff composes together, which are very fundamental computer science, concepts which a physicist would typically not think
about in first order. And that basically gave a completely new view on how to build a quantum mechanical formalism. Our first idea was basically to build the formalism as a high level language for quantum, just like any programming language is a high level language for zeros and ones in your classical computer. And we want to do the do the same for quantum, but then very early on, I mean, we I started this in
02/2003, '2 thousand '4. In 02/2005, we realized that the language we used were actually pictures. And these pictures go back to Roger Penrose. When Roger Penrose was an undergraduate student, he actually had to ill and he had to learn relativity theory. He basically realized that the symbols you typically use in relativity theory could be But it was only in the late nineties that people realized that it was actually gen genuine
mathematic. And then over in a process of twenty years, we've a great involvement with with Alex. We actually ended up with a formalism, which was entirely diagrammatic. The first the first subject were actually the students at University of Oxford, like postgraduate students. So Alex and I, we together started a course. And in the process of the the the textbook of this course is now a book called, Picturing Quantum Processes. It's thousand pages.
And so but then that book was not suitable for people without the right mathematical background. And then later, we basically, wrote this new book where we said, okay. There shouldn't be any a requirements in there anymore. So I'll end up, I'll end over to Alex who's now more hands on on these things. Yeah. So I've I think, really, for me, this started back around 2012 or so, when when Bob and I revamped the quantum computing course here.
So during my PhD, a lot of this early stuff about processes and things that Bob was talking about was all formalized using a kind of mathematics called category theory, which which is just a very abstract way of talking about processes in a general sense. But sort of toward the end of my PhD, we realized that the mathematics there wasn't so necessary, and you could sort of pull that out, teach everything with pictures.
And then over about a decade of me and Bob teaching this course, we were teaching people from a lot of different backgrounds, so not just physics and maths, but also engineering and some social sciences and stuff, and realized that that you can actually teach quantum concepts to people, you know, much more broadly
than that. And, I think that, that Bob and Stefano's book and then and then this experiment that we did last year with high school students was kind of the natural next step in that in in in making that a bit bit more broad. I see. And and in quantum mechanics is I mean, is there a a sort of long tradition of sort of simplifying things by well, maybe not simplifying is is is not the right word, but expressing things in terms of images or,
diagrams? Because, you know, I'm sort of thinking of, matrix, mechanics, and then you've got Dirac notation and Feynman diagrams. There, you know, there seems to be a a real desire amongst physicists to use graphical means to understand quantum physics. And, do you see the these pictures as a as a natural evolution from from those concepts? Yes and no. Like, know whether the desire is there. Because, I mean, one of the big, well known examples are Feynman diagrams.
So which Feynman diagrams are a calculation tool in quantum field theory to make your com computation much easier. Feynman had to fight really, really hard to get him through. Although now everybody sort of assumes, okay. That's that's, like, totally straightforwardly acceptable. No. It wasn't like that at all. And when you mentioned direct notation, I remember I was a student in the in the nineties in a mathematical physics, theoretical physics group.
People looked down on direct notation because it didn't have the sort of what they assume sophistication of the infinite dimensional complicated stuff. Okay. I'm gonna say something sociological here. So so the science as we know it physically is a very much used to be a very much white male dominated thing with a lot of ego and machoism. And so when I was a student in the '90, it was really about the more complicated it is, the better.
And we had to fight really, really hard to push this formalism through in the mainstream communities exactly for the reason that I said. People said, this can't something simple like that can't be useful in any way. Now meanwhile and, actually, Alex is more active in in that than me. All the main players in quantum computing, quantum industry, they're all using this. Now it's so widespread, but it took us so long to fight and to get,
things things basically published and and accepted. And part of the thing we had to do, which is what Alex alluded to earlier, is to use this abstract mathematical language of category theory to make it look more difficult than it actually is. And that's how we got our papers accepted. We had to get rid of that stigma of of this category theory, and that's why we wrote the big book because there was no mention of category theory anymore.
Okay. And I'd like to move on from, from from books into teaching. And in in 2023, Bob and Alex, I believe you you're both involved in a ten week summer course of short lectures that taught British teenagers, I think, age 15 to 17, how to apply the the concepts in quantum in pictures. Alex, can you tell us about that course? Yeah. So this was a course. It was also a kind of a pilot experiment for this this style of education.
So so it was a team. It was the project was jointly done by Quantinium and Oxford Computer Science, where we took, in the end, about 50, UK High Schoolers, from a pool of about a thousand people that volunteered, and gave them a course, as as close as we could kinda within our constraints to a Oxford Cambridge style graduate graduate course. So it was eight weeks of lectures, along with small group, tutorial sessions. So this was all done online, and then followed by a, take home exam.
So, the lectures were prerecorded and shared with the students on on YouTube. And then the and then the small group, tutorial sessions were were just, like, Zoom chat type things. So it was it was it was intended to be a kind of a interactive thing, but then but then also to to get to give a bit of this, sort of university style experience. I see. And and we've also well, we we're we're very lucky to have a a graduate of that summer course with us, Arjun.
Why did you, decide to take part in, in this course? Did you did you already have an interest in quantum physics? Or were were you just curious to, Why did you sign up? Yes. So I think it's probably more in regards to the latter part. I I would say I became, like, fascinated with quantum physics. I remember at that point, I had just finished year 12, and, I took a level physics. So by the
summer term, we started doing quantum phenomena. And I remember specifically, it was, we did this experiment with, I believe it's called, like, an electron gun, and we were looking at electron diffraction. And I just thought, like, the concept of, like, wave particle duality was just so cool. Like, I thought it was definitely something I would I would find fascinating, just the fact that it's so new and it's so unusual. And so I suppose that made me aware.
And then it was actually my friend who, was recommended the course by his teacher. So then he sent it to me and suggested, like, overshoot this together could be, something fun. I see. And and what did you enjoy most, about the program? Well, I I would say first thing, the lectures, it had to be Bob's, like, use of props and, like, just funny intros. That's always great. I remember we had this amazing skeleton and the spiders. That was always fun.
But I I suppose I actually enjoyed just getting more into the whole, like, making algorithms with the diagrams. And I suppose it's just a different way of thinking because, I mean, from school, I would never would have thought of using pictures to do math. I always would have kept separate ideas. So I think that in itself was quite interesting. I see. And and was it fun? Was it was it a fun thing to do, or or was it hard work, or was it a bit of both?
I'd say a bit of both. Like, it was definitely enjoyable throughout. It did take some time to get used to. Although, interestingly, I feel like these are pictures that feel quite intuitive because it's something, I guess, you can conceptualize a lot of the times. I did feel like I did have uncertainty as to whether what I was doing was actually correct. So I think, initially, I did struggle with being confident in my ideas, but it did feel pretty intuitive, I'd say.
I see. And and did did you have much contact with with your fellow students? Did did you get an idea for for who they were and and and why they were there? Partially. I suppose, mainly contacts was through tutorials. And so I guess there was a there was a range. There were some people who would love to, like, also speak up and we can engage, and some who are more reserved. I suppose, Bob, do you have something you'd
like to say? Yeah. Bob, go ahead. So so we had a lot of restrictions imposed on us because we were doing an experiment with minors. So one of the things we wanted to do is a lot more social media so that students could interact with each other, but we were told, no. Not do that. And so it was quite a bunch of restrictions that we were imposing on us to the extent that at some point, I said, no. We are just gonna pull it because this is not a normal
teaching experience. And then Alex convinced me to to keep going because I thought, okay. This is not gonna work. This the results are not gonna be good because this is not a normal I mean, I should say something else, and I don't want to embarrass Arjan, but like, most of the students just had a black screen. And and they didn't ask questions. They typed questions. And then I wrote, like, an email, a long email saying, please, please, show your
screens and speak. Because as a teacher, we need to see your facial, like, articulations. We need to hear the tone of your voice because that's part of a teaching. Teacher teacher student interaction. And I think for, yeah, five seconds, some some screens went down, and then they were back again. So so it sounds, Arjun, that, the the sort of remote nature of it was a bit difficult. Or or or I don't know. Maybe maybe you were happy with,
with that. Or is there anything is there anything else that you'd add, to what Bob said in terms of how it could have been improved? I mean, I'm guessing actually going to Oxford, if that was possible and and doing it in person would have been fantastic, but maybe not possible. Yes. I think, overall, I suppose, just naturally teaching online is a bit like, it can be quite in person. And I guess as Bob said, not many people did always turn on their cameras or respond.
I just feel bad sometimes for some of the tutors because we had that awkward silence for a couple of seconds. Mhmm. But, I mean, I I suppose some benefits was that sometimes I would I would be able to message my friends and we could, like, we could discuss things, somewhat freely. But I guess that, that was not to the benefit of the tutors because they have no idea what we're discussing.
But yeah. So so I think just the online like, as you said, being in person would have been, perhaps a bit more invested. But yeah. And and so what's your view on quantum physics, after having taken the course? Are you I I I understand you you're at university at the moment. Are are are you doing physics? Do you do you plan to pursue a career in quantum science and technology, or have you have you put your interest on the back burner?
I would say yes. I, like so I'm currently studying mathematics, but it was one of my intentions to actually do, like, the quantum modules within my second and third year. So I'm now coming towards the end of my first year. And, yes, I thought, and I thought it's one thing because I do remember speaking to lots of tutors about, like, as, I guess, Bob said, like, there's lots of a mat, maths
towards it. And I thought perhaps by doing just maths, then I would be able to understand those, like, I'd be able to read more literature and perhaps have better understanding. And so, yes, I mean, I would say I haven't done much more in terms of the extracurricular side. But I think just also seeing the possibilities throughout the course, like, just creating algorithms seemed fascinating to me.
I remember I think they did mention one about solving prime numbers or, like, factors like prime factorization using, like, quantum algorithms, I thought was really cool. I see. And you as a you you're doing maths at university, but it I mean, for maybe for the benefit of of of high school high schoolers who are listening and thinking, should I do physics? Should I do maths? Do you have the opportunity to do physics
as a mathematician? You know, for example, doing, mechanics and and quantum physics. If you wish, can you can you study those things in your course? I suppose yeah. So currently, I just wanted to just show some mathematics I can. I think in the first term in the first year, a lot of the content is kind of pre cited. You get at least at Durham, we have one optional module. But then I don't think that goes towards
quantum. It's only as within your second year where you could start to specialize more towards, perhaps, like, quantum modules, mechanical modules, statistics probability. So I suppose definitely later on. Although, I do guess there's also the option of natural sciences in which, we can choose a combination of subjects. I like to do maths and physics as as an option. I see.
And and what about the future? Do do do you see a a career in quantum science and technology in in your future, you know, after you've done after you've finished with university? I would say probably, definitely, yes. Because I think the quantum space seems to, like, encapsulate all of my favorite subjects. Because for instance, for a levels, I did math both math, physics, computer science. I guess quantum computing is, in a way, all of those.
So I think also perhaps because it's so new, I think it's something that would always keep me interested. So I think something I would always be enjoyed and pretend doing regardless. I see. Good good stuff. And, I mean, obviously, the the summer course has been, well, Arjun has you've really enjoyed it, and it's encouraged you to to look at quantum science and technology as a career. But but, Alex, I understand that it's it's not just Arjun who's who did very well.
You you you had, you had the students sit a university level exam on quantum physics at the end of the course, and, I think you were extremely pleased with the outcome. What what happened, Alex? Yeah. That's right. So so at the end, we gave them an exam which had all, previous, exam questions that that Bob or I have given on an exam to master students in
in past years. So we just sort of put that together, adapted a little bit to match the terminology of the course, and just gave that exam, really having no idea, what we're what we're gonna get back from this. And we're pleased to see that most of the students passed and, something like forty percent, or, yeah, around around that actually got distinctions or or first class marks and things. So so, yeah, that was really great.
And one of the things I noticed kind of qualitatively when marking the exam is that some of the students understood certain concepts and possibly even even in a better way than I see, with the graduate students. So so really an example of that is this idea of nondeterminism, in quantum theory. So for instance, I do a I do a quantum measurement. It collapses my state, and I I don't get to control
what state it collapses to. Right? So the quantum theory has this idea of this kind of irreducible nondeterminism, and quantum computing really uses this in in the way that it designs some things. Right? I do a measurement. This has some sort of action, and I have to account for that in a certain way.
And I saw in the way that that many of the students answered these questions that they that I think they understood that in a way that that was sort of more fundamental, I would say, than than than than some university level students. That that could be that they they aren't as accustomed to a more traditional or classical way of thinking already that a computer scientist or physicist would get in in in university. And, Arjun, did you enjoy doing the exam? I mean, maybe enjoy is the wrong word.
But, did did you, did did you find it was it a nice way to end the course? I think so. I mean, I'm very reluctant to say I enjoyed an exam, but, it was definitely nice to have, I guess, more like, because I think one of the things is, actually doing lots of questions were really interesting because it was a way to practice and actually apply what we had learned. And, I guess the exam was definitely a nice way of doing it. And, gosh, I'm trying to remember exactly.
It's been a while. But I think, I I mean, I remember slightly struggling with it initially, because it was once again, it was one of those things which is uncertainty. Like, how how right is my answer? How correct is it? But, no. It was definitely, interesting and enjoyable. Oh, that's great. And, and, Bob, final question, for you. Do you think that a version of the summer course could be integrated into a high school physics curriculum.
And may maybe that's something that that you and Alex and your colleagues are working towards now. Is is that something that we could see? It is already happening, actually. Like, Greece was the first country to basically start using, this this language methodology at high school level. So that there is a translation out now, which was really pushed by by the the the mathematics sort of teaching council in Greece.
So, I mean I mean, it's probably not an accident that it's Greek because as I was hinting at earlier, this language is not something you contrast with classical physics. I think this language basically goes back to before 2,400 of western scientific tradition to the pre Socratics in Greece. Because that's the moment when western science decided to become mainly it, reductionist following Democritus and having quite a static kinematic based view following a guy called Parmenides.
On the other hand, you've got people like Heraclitus who had, like, a process based view on reality, Leibniz who has, like, an interactive relational view on reality. And these pictures, without people probably realizing it, they are much an embracement of a post process based view and an interactive view. And, so so so something Alex was hinting out, about, like, they didn't the people maybe not have been much as much as subjected to, like, western thinking may actually be an
advantage. We kind of saw that the 15 year olds were doing better than the 17 year olds, which kind of proved that point that the less you've learned, the less you have to unlearn. And that's in particular why I think it's really important to start this stuff very early. And, I got a few people now working on
this. Like, we're we're we're talking to many, many places in the world, like, where they want to start this in a pro so one country is, like, wanting to do high school, teaching using this is Ghana, for example. So and, we we also have a collaboration which is now now funded with Colorado Colorado state schools. So several places in the world are starting to, have we we we are doing an Ukrainian translation, by the way, too, on the initiative from Ukraine
of of the book. So lots of places are now starting to want to integrate this, But it it's all quite recent. You know? So it's a very ongoing process, and I expect if we speak in a year about this, their story will be much more advanced and much more, yeah, broader in where and when this stuff is being, integrated in high school curriculum. But it should be. It should
happen. It's not just about quantum. It's about a changing world view to a more relational and process kind of way of thinking, which which also makes the the sciences and humanities a little bit closer. I see. And and what about you, Arjun? I mean, you're out of all of us, you're the closest to to having been in high school. Do I mean, do you would you have enjoyed, seeing this material, you know, when you're doing your physics a level or a mathematics a level or even, at a lower level,
at a younger age in high school? Do you think it would be it would be very useful? I'd yeah. I definitely think so, because I think it's something that could, it could be like a nice way to kind of unite, I guess, physics and computer science. So for physicists and computer science students, it, I mean, perhaps creating some algorithms where they're, like, perhaps more
simplistic, could be nice. And then also, I suppose that, it would probably make people more aware, of just, like, a small if I call it physics, I guess, by just, giving more exposure. And so, yeah, I think it definitely would have been nice. And I think also, as both Alex and Bob Sway were saying, by at that point, we've learned less classical way of thinking, for math and physics. So it would be it would make that easier more intuitive.
I see. And and maybe I'll I'll throw this out to to Alex, first. What about even younger children and, you know, people who have done finished their schooling? You know, I'm thinking of primary aid primary school age children and, just just the interested public. I mean, is there a is there an argument for introducing or coming up with ways of introducing quantum physics, to to those groups of people. Yeah. I think I think so.
I mean, the, the original paper of Bob's that kind of kicked off this education idea was titled kindergarten quantum mechanics, which I think was a bit of a tongue in cheek title that, you know, we could teach quantum mechanics to kindergartners. But, I mean, I think it it'd be interesting to see just how far we can we can push this. And I I think for instance, you know, I know anecdotally cases of 12, 13 year olds reading reading Bob and Stefano's book and getting a lot out of it.
So thinking about different different levels to pitch that at and also also having more materials that, you know, you can just share with your friends. Like, so for instance, if people are interested in pop science, but they don't have a mathematical background, they can sort of this kind of stuff, you can get your teeth into in a way that you can't, with a pop science book because here, you know, we give you something, and you can
really do some calculations. You can see what quantum theory is gonna tell you will happen. And I think that could be really appealing to a lot of people. Okay. Well, that's great, guys. Bob, Alex, and Arjun, thanks so much for, speaking to me. Arjun, best of luck with your career in mathematics and hopefully, quantum science and technology. And, Bob, hope everything's going well at Quantinium. And, Alex, best wishes at Oxford. And thanks so much to all of you for coming on the podcast.
Alright. Thanks, Hamish. Thank you. Thank you. It was a pleasure to speak to you. I'm afraid that's all the time we have for this week's podcast. Thanks to Bob, Arjun, and Alex for joining me today, and a special thanks to our producer Fred Isles. I'll put links to Bob and Alex's books in the notes for this episode.
We'll be back again next week, but in the meantime, do check out the latest episode of the Physics World Stories podcast, which features an interview with Linda Williams, physicist, performer, and self styled physics Chantouse. She tells host Andrew Glester about her latest show called Atomic Cabaret, and they chat about how she combines science with music, satire, and performance art.
That episode is called the Physics Chantouse, when science hits a high note, and you can find it on the Physics World website or at your favorite podcast provider.