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Okay. So first, I'd like to welcome all of you to the Department of Physics.

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And also to welcome you to the inaugural Particle Physics Christmas lecture on behalf of John Wieser,

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the head of particle physics of physics and the head of particle physics.

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So let me tell you first that particle physics has been studied here in Oxford since the early 1960s, and it's modern form.

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That Oxford physicist played a leading role in establishing our prevailing theory of particle physics called the Standard Model.

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It's a remarkable theory that in some cases can make predictions with precision of one part in 10 billion.

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And it's found to be accurate. A towering achievement that is recognised perhaps as one of the greatest achievements in all the

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science over the 20th century was capped off in 2012 with the discovery of the Higgs boson.

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Now we do this work here at Oxford through making measurements of the universe, and we're joined by colleagues around the world in doing so.

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And as we made those measurements, what we've discovered is that there's much more about this universe than is in our standard model.

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And to paraphrase Newton, what we know today is just the drop in.

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What there is to know is an ocean. That's our job on the generations in front of us to explore that ocean.

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And so we do that here and around the world, building very large and sophisticated instruments and analysing the data that they

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take on this day to look for evidence of what is the true nature of your retreat.

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What do we really mean by cool? What do we mean by an electron?

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We don't understand these most basic things. We also don't understand why galaxies are held together by dark matter.

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What it is we try to find both deep under the ground and also by crazy.

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And we hope that the Large Hadron Collider will so good telescopes that map the cosmos and

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try to understand the mysterious energy that drives galaxies apart and ever accelerating.

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Right. And all of that work is made possible by the taxpayers of the world.

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And in the UK we are especially privileged to receive great support from the UK

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taxpayer on the wisdom of governments that decide to invest that money in pure science.

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But at the same time,

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we are mindful of the fact that many international partners around the globe enjoy greater support for the science that we do here in the UK.

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In fact, the UK is eighth out of eight in the G8 in terms of fraction of GDP that's devoted to science.

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One of the reasons why we've been successful at Oxford is because in addition to that important and essential support of the taxpayer,

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they've also benefited from the support of foresight about benefactors.

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And I would like to give you one example. Later today, we're going to see an exhibition of the Sudbury Neutrino Observatory experiment upstairs.

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When the next round was built, Oxford played a unique and leading role from the only UK university on the experiment.

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When you go into that exhibition, you're going to see 20.

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Fill theses of Oxford from students that help to make that experiment work, along with the work of engineers and scientists and academics.

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And they play to the crucial roles. One of the students played an especially important role in an analysis technique

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that enabled the evidence for neutrino oscillations to be established.

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And this led to the conclusion that neutrinos have mass, and this led to the Nobel Prize for physics in 2015.

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And that students name was Jingsheng. And he was only here because of the wisdom of private manufacturers that supported these different studies.

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Now, one of my colleagues today leads the new version of snow.

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Snow Plus in his head at the moment is actually going to get a statement that

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will tell you and all my colleagues who tell you how much they need students.

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But the science funding falls. The number of students that the UK government provide across all of science is far less than we need.

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Fortunately, last year we had wonderful news that one of an anonymous donor from particle physics was going to create the new student in perpetuity.

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The difference being that John has launched now a programme to raise funds for the Oxford Endowment for graduate students,

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which could expand that over the next five years to raise sufficient funding to support 25 students at any given time.

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And what those students would earn is going to go off from that experience and explore the future, the future, that future of particle physics.

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And they will perhaps one day win another Nobel Prize or two.

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And that's why we've been glad to do a move, as they are here today, to tell us about that remarkable future that particle physics has.

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So, John, as you know, is the director of the Directorate General.

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Yes, that's what it says on the business card advert.

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But as you probably also know, until very recently,

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John was the chief executive of the Science and Technology Facilities Council of the United Kingdom,

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which is responsible for supporting and glider and particle physics and nuclear physics

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and astronomy and large science facilities and national laboratories in this country.

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And John has been here before. He started out as an undergraduate at Cambridge.

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He then had the other faces, the other face, and decided to take his dphil here.

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And one of the people that interviewed him on the day he decided whether would accept him or not is sitting right behind Plan B.

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It's no, it's not a wise, wise decision.

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I'm going to tell you what he was telling me about your Internet. Ask me about any catch he got.

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He managed somehow to get through the internet in about three or four days later, he managed somehow or other.

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It actually got to be felt as he went off to the United States with a [INAUDIBLE] of a reputation and became the leader of the D0 experiment.

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Fermilab, Tevatron. One of the most important experiments prior to the LHC is the one that discovered the CPU, for example.

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And then he went on to advise the U.S. government through the U.S. Department of Energy, the first particle physics in the United States.

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And then in 2005, he came back to the UK to become the head of the particle physics department of the Steps,

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as well as the amplitude laboratory after several years in that role.

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But I realised how talented this guy was. A mechanical business was just too small for him.

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I'd say it's become a director of programs in science.

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Yes, yes. And then in 2011, he became the chief executive of C and a guy did a very remarkable and very

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successfully until a few months ago when we lost to the Europeans collection source.

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Now, John, of course, is sought for his mission around the globe.

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And so he serves and advises in many capacities, including CERN, Cultural Board of Fermilab and the Board of the Square Kilometre Right Telescope.

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He's also chairs the European Strategy Forum and Research Infrastructure and plays a role in

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the expert group on cost management and road control large facility infrastructure for Europe.

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And he serves on many boards for his sage wisdom and to those kinds of home votes association and what remarkably, the human brain project.

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Yes, it's saying any more. I'm going to tell you about the remarkable future of particle physics.

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Thank you, John. Thank you. Yeah, I'll happily tell you about the Human Brain project over lunch,

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because that's an example of, you know, particle physics, knows how to do big projects.

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Not all fields of science do and excellent science there.

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And really the management wasn't particularly good.

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So let's start by looking back because I'm I've been asked to talk about the future of this field.

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The future is defined by recent discoveries because those have set the direction in ways that were not the case five years ago.

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And when we lay out the future today, it's not the presentation that would have been given a few years back.

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That's a sign of a dynamic field, and that's a very good thing.

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But it means that we we also have this paradox that while we know more, we actually know less about what we know than we thought we would.

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And again, all signs of a dynamic field. Now, first of all, I should say I had no idea what the target audience would be.

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And I still don't quite, because I know that I've I know some of you are practising researchers in this area.

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Some of you are practising researchers in other areas. Some of you look more like undergraduates or graduate students.

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Some of you are alumni who have gone off to do other things.

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So I've really tried to pitch at that latter group much more.

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Those who have an interest in physics, a knowledge of physics, but who may not be up to speed with it.

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And so for that reason, there are very few equations here, lots of pictures and some snide comments from the presenter,

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which is the real reason they put me on advisory committees. I think provide a little entertainment.

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So the big thing that happened in the last five years for particle physics was the discovery of the Higgs boson.

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As Ian already said, I had, I should say he pretty much summarised my talk in his introduction so we could stop that.

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But I think the visual materials are too little.

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So this was the culmination of decades of work and the proving correct of a theoretical supposition which had first been made in the mid 1960s.

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So the the theoretical framework that Peter Higgs put together was then incorporated in a larger set

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of mathematical models and equations that we came to call the standard model of particle physics.

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And that was, as Ian said, successfully tested generations of experiments in the United States and at CERN to extraordinarily high precision.

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But this last piece of the puzzle, the Higgs boson, had never directly been observed.

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So there was a lot of indirect reasons why it would be.

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Strongly believed to be that.

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And that led to a high priority being placed on building the experiments and facilities necessary to see if it was indeed there.

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Because even if it was, if it were not to be found with the properties that Mr. Higgs had predicted, that would have itself been a major discovery.

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In fact, while we would have struggled to explain that to the public and politicians,

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it would have been a far more interesting outcome than what did in fact turn out to be the case,

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which was we discovered they discovered a particle with the properties almost exactly

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agreeing with those that had been predicted in the Higgs theory five decades earlier,

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which when you think about it,

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it's an absolutely amazing accomplishment for the the theoretical basis on which this field sits to have sufficient precision

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from the measurements and sufficient confidence in the set of equations that you can spend substantial number of billions,

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work for many decades and be vindicated by finding exactly what you had predicted.

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Almost too good to be true. But it is true, and as you can see, made the front pages of the general press, as you will remember,

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if you were around at that time and even Brian Cox is in awe, it doesn't happen very often, does it?

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So so here is the man. And of course, he went on to receive the Nobel Prize, along with some collaborators there and.

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The Higgs is part. This is the only equation that appears at the top.

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The Higgs is the missing piece. Then, in this structure, which is the Lagrangian of the Standard Model, a very compact notation.

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If you go to Wikipedia, you will find the full equation laid out.

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It doesn't fit on your screen when you scroll through it, not just on a phone screen, but a laptop screen.

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Each of the the bits of notation here actually expands into many, many terms that describes the interaction of the electrons,

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the neutrinos, the up and down quarks, the bottom and strange quarks,

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the top quarks, all of the components of of matter, the forces that mediate their interactions,

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the gluons with the strong force, the weak interaction with the W and Z and the Higgs.

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And the Higgs is there for mathematical consistency in this theory,

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but it's also there because without it you wouldn't be able to construct something which gave

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mass to to the W and Z and created a slower rate of radioactive decay and so on and so on.

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So there was a lot of reason to believe that this was probably true.

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But we are experimentalists at heart and we want to test and oh sorry.

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I should just remember the Higgs.

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The argument for why the Higgs was important was something that led to the construction of the Large Hadron Collider at CERN and

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what motivated the building of 26 kilometre particle accelerator underground in the tunnel that had previously been used for LEP.

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And at the time, in the 1980s when construction was being approved, we were confronted, as he had said,

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with the need to sell this to politicians and in a shameless piece of arse licking it was,

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it was presented to Mrs. Thatcher as the interaction of the Higgs is analogous, madam,

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to what happens to you when you try to enter a room and you get mobbed by people.

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So basically the role that the Higgs plays in less mathematical terms than John Ellis here, our colleague from from King's College.

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By the way, this is the mathematical description. This is the layman's description.

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The Higgs is responsible for mass of the elementary particles.

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The reason why quarks,

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electrons and so forth have masses is because they're interacting with the Higgs in the same way that in this this this layman's description,

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Mrs. Thatcher is unable to travel smoothly through the room like a massless photon,

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because she gets grabbed and slowed down by all the would be conservative MPC who want to talk to her.

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I could pass smoothly through this crowd without being interacted with,

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and that is what happens to massless particles like the photon or nearly massless ones like the neutrino.

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They have weak interactions with the Higgs field.

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Particles that interact strongly, gain drag as they pass through the universe, and that is what we call mass.

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And then there's a separate question of what that has to do with gravity, and we'll come back to that later.

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So this is more like what's actually happening. If an elementary particle travels through the universe,

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it can travel in a way that has very little drag, like a marble rolling across the smooth floor.

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And those are particles with low mass.

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Or it can travel with a lot of interaction with the universe, a lot of interaction with the Higgs field that permeates the universe.

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And that is what we call a massive particle. So we built we a Large Hadron Collider was built.

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And you can see Peter Higgs standing here in a very small segment of this 26

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kilometre tunnel under the French Swiss border regions just northwest of Geneva.

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And in this accelerator, which is to his right there, particles are accelerated up to, you know,

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very close to the speed of light, so that the total energy in the collisions is 13 trillion electron volts.

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For those of you who who understand what that means,

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particles are then brought into collision at two locations where two very large detector systems study the results of those interactions.

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And this shows a computer reconstruction of one of those collisions in one of those detectors.

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This is the Atlas experiment, and I managed to choose the one that Oxford is involved in with a certain amount of care.

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And what happens is that the Higgs well, most of you, if you are here, did study some physics.

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And so you will remember you will remember that when there is a quantum field like this,

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Higgs energy, which we are postulating pervades the whole universe.

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You can excite quantum states in that field.

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So the the ground state is is filling the universe with a certain amount of energy.

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And that's what interacts with all the particles and gives them mass.

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If you put enough energy into that field, you can create the next quantum excitation.

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And that's what we call the Higgs boson. So this is real quantum mechanics at work.

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That excitation decays after about ten to the -20 4 seconds.

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And what it decays into are normal long live particles and those.

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Are entirely predicted within the framework of the standard model.

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So if the Higgs is what you think it is, you know exactly what you should look for.

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You don't see little Higgs is coming out saying hello. Here I am, you know, sticking their head through the curtains like that.

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What you see are the decay products of this particle.

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And the way you know that you have that extra thing being produced is that there is an excess of

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objects with an inherent mass that you can reconstruct back to the thing that they decayed from.

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And so that is what you are seeing here. This happens to be the invariant mass of pairs of photons.

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So the Higgs is decaying in this particular event, this collision into two photons which were measured in the atlas detector.

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And there is an excess that you can see above the smooth prediction that you would have if there were no Higgs.

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And the mass at which that excess takes place is the mass that you infer.

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The Higgs has the rate of particles, is the rate at which the Higgs is produced, and you can check whether it decays into other things as well.

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And it does.

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And all of those properties turn out to be exactly what you would expect, which is great news and the worst possible news at the same time,

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because if it was not what you expected, you would have opened the door to an entirely new world.

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If it is what you expect, you've completed a checklist.

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And so that's where we are now. There remain many open questions which are continuing to be addressed at the experiments at the Large Hadron Collider.

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So the first part of the future of high energy physics is continuing to explore this newcomer,

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which has landed on our doorstep in the last four years, which appears to be exactly what Mr. Higgs told us was going to land on our doorstep.

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But we should verify and tested every possible way. So is it actually the standard model Higgs basically summarises all of this.

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Does that therefore mean it's responsible for the masses of all of the particles?

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Well, one way to check that is if it does indeed interact with all of the particles it proportional to their mass,

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you should see it decaying into each kind of particle proportional to the square of the mass.

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And that's a very simple prediction, a very hard to test, but it's a testable prediction of the model.

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Are there other Higgs bosons? Are there other heavier partners?

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You could construct an extension to the standard model, which had four.

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Higgs is not one, and there's nothing wrong with that.

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It's not necessary. Nature may not do that. It is not necessary, but it would be consistent with all the mathematics so far.

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So we need to test that the Higgs might not be an elementary particle.

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You could create a quantum mechanical field with the properties of the Higgs from two smaller things stuck together,

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just like the proton is made out of three stuck together just like the pion is made

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from a cork in an antiquark the Higgs could be made from a thing in an anti thing,

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and it could still have the quantum numbers that the Higgs has, and it could still behave the way that the Higgs does.

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So that again is hard to test, but it's a possibility, not in the standard model.

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The Higgs might be the first of a long list of new other particles, and that happens in extensions of the standard model.

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For example, we'll talk in a little moment about supersymmetry, which is a very popular,

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long cherished extension to the standard model by our theoretical colleagues, but which hasn't so far shown up in the experiments.

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And then there are questions about the Higgs itself. How can a particle like this have such a low and finite mass?

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Now its mass is actually quite high on the scale of the proton and the neutron.

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But on the scale of the energy of of the universe, it is it is quite small.

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And the reason that that's challenging is that because the Higgs interacts with everything,

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there are very large quantum mechanical corrections to its own mass.

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And just like any other particle, you need to to calculate all of the quantum mechanical corrections to any property.

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And in the case of the Higgs, it's a divergent series. The perturbation theory doesn't stop and its mass could be infinite or zero.

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We don't know what it is.

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So the mass is the single unknown parameter in the standard model, and there's actually no reason why it should have a finite value.

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There must be something else going on. And the Higgs is also a strange thing.

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Unlike the electron and unlike the neutrino and unlike the top cork, the Higgs has a value.

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The Higgs field has a value which fills the entire universe, fills this room,

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not because there's lots of Higgs is passing through us from cosmic rays or anything,

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just because there is energy in the space time associated with the field of the Higgs.

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And it's actually way too much. It's like 10 to 120 times more than we think is in the flat universe that we happen to live in.

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So that's a little bit of a problem. And we don't know, well, if the Higgs was the only thing,

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the universe would have expanded so rapidly that we wouldn't be here or it would have collapsed into something the size of a grapefruit by now.

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So again, there's something else going on in cosmology, and we already know there's a lot else going on in cosmology.

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So our best models of why the universe is like it is have very rapid expansion in the early femtoseconds of the life of the universe,

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which we call inflation. There appears to be something called dark energy, which is making the universe slowly expand faster.

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And both of those phenomena have the same kind of properties that the Higgs field does.

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That's an energy field that appears to permeate the universe with the same quantum numbers that Mr. Higgs this thing has.

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But they don't appear on Jon Ellis's T-shirt.

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There's no dark matter, no dark energy, no inflationary expansion here.

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So we know that something else is happening along with the Higgs thing. And it seems to be it would be nice if it was in some way connected.

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All right. Supersymmetry is the most popular theoretical prejudice.

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Addressing that list of questions before the Higgs was found was that the Higgs was the first of a whole array of other new particles,

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and that I'm going to refrain from showing you the list of particles that particle physicists always show you,

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because you don't need to memorise how many quirks there are. You just need to know that if supersymmetry is true, this twice as many,

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and the new ones have properties related to the existing ones, but they're heavier.

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So we haven't seen them yet.

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And they have different spins which which quantum mechanically makes them cancel out some of the corrections to the Higgs energy in a nice way.

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The supersymmetry would also predict some very nice properties too, to tie up cosmology with particle physics,

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and it would make the universe an easier place for theoretical people to.

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Sorry, this is going to sound demeaning. It is easier to relate to string theory and fundamental calculations about trying to

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tie together gravity with with with the particle physics that we know and understand.

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And so it's quite likely that the universe is, in some sense supersymmetric,

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but we have no idea if it's supersymmetric at the energy scales that we can explore with our current experiments.

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And in fact, it seems not, though I'm going jumping out a little bit on a limb here,

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because so far we haven't found any evidence of any other Higgs or any of these other supersymmetric particles,

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even though we can predict their properties relatively precisely.

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So five years ago, if you'd asked people what you will, will you have found by now at the LHC,

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most of our theoretical colleagues would have said a Higgs, maybe not the standard model Higgs plus one or two of these supersymmetric particles.

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That would give us some indication that there's a bunch more going on.

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We found a Higgs and we haven't found any of this other stuff. So what can you do?

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Well, you can make the best of the tools you've got and continue to enhance their power and their capability to explore.

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Because as the LHC collects more data, we are sensitive to rarer and rarer phenomena,

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which means we're probing higher and higher mass scales for these new particles that may be predicted beyond the standard model.

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We're also looking at smaller and smaller deviations of the Higgs from the properties that the standard model would predict.

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So there is a rolling program grading the Large Hadron Collider.

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So the Higgs was discovered using the data from 2012, and that was sufficient to discover the Higgs.

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The energy was then upgraded and the run that we have that we've just taken this year was taken at higher energy.

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And that's produced greater opportunities to test what is going on with greater precision.

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But unfortunately, it hasn't yielded any new discoveries.

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The LHC will be upgraded again in the long shutdown in a couple of years time and will run at a higher in collision rate for a number of years.

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It will then be given a much more major upgrade at the end of this decade, which will enable it to operate for ten more years.

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And you notice we haven't even put an end date on here.

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So it will run into the 2030s and collect data sets which are of the order of 100 times larger than currently exists.

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So that's sufficient to make really insightful discoveries beyond what we currently have.

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If nature has given anything that can be produced at the LHC, if nature has not,

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we'll be able to measure the properties of the Higgs with really quite surprising precision in this very large dataset.

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Now, this is not simply a question of turning up the power and and dialling up the energy.

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The machine will have to be substantially rebuilt.

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It's 26 kilometres long and at least one kilometre of that will be ripped out and replaced towards the the the long shutdown here in the 2020s.

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And it's shown in red on this and the schema,

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the technology that's needed because most people in this room are probably techno geeks at some level is higher

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field magnets which will enable the CERN accelerator people to focus the beam more strongly at the collision points.

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And that increases the probability that the two co rotating counter-rotating beams collide

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head on and therefore increases the collision rate and you get more collisions out.

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In order to do that, you need higher field magnets in the collision regions close to where the experiments are.

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And that means going beyond the current kind of magnets which are made of a niobium titanium alloy, which I think may have been invented in this.

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Building or across the road, there are two new materials Niobium Tin, which are fiendishly hard to work with,

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with cryo heat treatment and all sorts of difficulties putting together, but enable you to build much higher magnetic fields.

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And that focuses the be more and gets higher collision rate and that will enable the LHC to continue to be a frontline facility into the 2030.

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So this is an international development project.

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This magnet is actually sitting at Berkeley in California and there are some UK contributions to this as well.

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So the LHC will continue to be a frontline tool and will continue to be the Higgs factory that we can

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depend on to make millions of these particles and enable us to study their properties at the percent level.

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But if you really want to become a precision measurer of Higgs, you may wish for a cleaner environment than the Large Hadron Collider produces.

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Because you remember that collision that I showed you?

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There was quite a spray of other particles coming out of the collision point, along with the things that came from the decay of the Higgs.

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And that's inherent when you collide. Protons head on. There's lots of other stuff in the proton.

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They produce lots of other particles, some of them low energy, which are easy to remove,

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and some of them are higher energy, which can confuse what you're measuring.

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So for a a long time, scientists have been thinking about what you might do beyond the LHC.

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You can continue the evolutionary path of Large Hadron Collider cars, and you could build a larger Hadron Collider.

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And this is a deliberately sketchy attempt to show how that might fit in the region around CERN.

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In the Geneva region, you can see the LHC shown there.

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So this is an 80 to 100 kilometre tunnel and some preliminary engineering studies,

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geological studies, geotechnical studies have been done on this such a tunnel and it could be built.

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Unfortunately, you also get some sense of what it would cost because the Swiss know what tunnelling costs and it's not a small number.

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So open your chequebooks, please, on leaving. But this would enable you to study in detail.

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Not just the Higgs, but to produce pairs of Higgs is to see how it interacts with itself and any new particles that are just coming in to view.

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When the upgraded Large Hadron Collider is running at the far right of that previous plot would be much,

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much more copiously produced as this graph tries to show.

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So hundred times gain, for example, for heavy particles compared with the LHC.

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We do know that this is not a cheap and easy thing to do,

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so it's something that would be unlikely to happen without some very strong motivation behind it.

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But technologically, it's intriguing to see how you would build such a thing.

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And this is by saying little graph about magnets. To do this, you would need even the higher field magnets unit.

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The 11 Tesla dipoles that would be required for the LHC upgrade are the first step here, but we need something like 20.

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Otherwise you have to build a two or 300 kilometre tunnel and that becomes prohibitively expensive.

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And that means going to high temperature superconductors, non-metallic conductors in magnets.

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The costs are 5 to 10 times higher right now, so those need to be pushed down.

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But if you could build 20 types on magnets,

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it opens up the intriguing possibility that you might install those in the Large Hadron Collider tunnel, the existing location,

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and that would enable you to get to significantly higher energies relatively cheaply

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compared with the cost of building 100 kilometres of of subway tunnel around Geneva.

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So R&D on this kind of high field magnet is something that would obviously benefit lots of other areas of science beyond particle physics.

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And it's a it's something that I think should be a is a priority for the future.

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Now, as I said, you might want to study the Higgs in more precision,

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in which case you don't need higher energies, but you need different kinds of beams.

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So for a long while, scientists have thought about building a precision collider to take a beam of electrons in a beam of positrons and bring

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them head on into collision with sufficiently fine focus nanometre sized beams that you can collide and produce Higgs.

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In this case, it would be producing a Higgs with a Z technically, but that would give you a very clean sample of lots of Higgs,

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and this is a fairly well worked out design for a 30 kilometre long straight accelerator that will collide

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electrons and positrons head on with an energy optimised to produce lots of Higgs is what's not to like.

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Well, a lot of R&D has been done on such a thing.

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Several hundred millions have been spent to develop the technology.

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The key technology for this is the accelerator.

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So in contrast to a circular, circular collider where you're trying to bend the beams in a circle here,

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you just want to get them to the highest energy in the shortest possible distance.

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And that uses superconducting radiofrequency accelerator like this.

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So as the beam passes through, it gets a little kick of energy from each one of these cavities, which has a standing wave set up in it.

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And that's a superconducting cavity.

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So there's no dissipation of the energy, which is a very good thing to do, but it's a relatively expensive technology.

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We are using it at SS. It's been used in other, other locations.

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It works, but it is not as cheap as people had hoped when it was originally proposed.

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So I've sort of I've chosen my words carefully there.

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I haven't said too expensive, but it's certainly very expensive.

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And one possibility is that such a machine might conceivably be built in Japan, or at least there are people in Japan who would like that to happen.

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Now the Japanese government has other priorities like hosting the Olympic Games,

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so it remains to be seen whether they would invest the huge amount of money that it would take to put a a major contribution in here.

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But this is the the coordinator of the project meeting the Japanese prime minister.

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So, you know, it's not it's not as if it doesn't have traction at government level.

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The other possibility, which has come in from the east, is that this idea, if a linear collider turns out to be a little bit too expensive,

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maybe you should consider a circular machine which can produce lots of Higgs.

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And a few years ago people would have said, Well,

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that's not a sensible thing to do because we know that the cost of circular accelerators is basically going to go up like the square of the energy.

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Sorry, another equation I apologise. Whereas linear colliders should go up like the first power of the energy and therefore above some some point,

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it should be cheaper to build a straight one than than a circle.

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Well, it's turned out that the straight one is a I shall avoid words like fiendish but more expensive than thought.

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So this has created interest then in China of all places,

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for potentially a very large circular accelerator that could be built as an electron collider.

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First, produce lots of Higgs boson and then later upgraded to do something like that.

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Future Circular Collider at CERN.

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Now this is a design study that's been pursued by the Chinese Academy of Sciences and the Institute of High Energy Physics.

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They put in a proposal to the five year plan, which is apparently what you do,

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and they got R&D money, which is good, but it's not a huge chunk of R&D money.

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So there's a few lessons for here. We often look at China and think, as soon as someone in China says Do this,

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it happens because the Politburo signs up and they have unlimited billions.

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It's more complex than that. I'm watching this project from outside is surprisingly revelatory about decision making processes in China,

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which are not as politicised as you might think. There's a scientific review process in the academy.

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There are scientists who speak out against the project because it would be too expensive.

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There are others who say, No, we really need to do it to put China on the map for fundamental research.

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All the same arguments. It's just that they weren't elected. They make all the same arguments.

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In fact, they're probably more intelligently made because the Politburo is full of engineers.

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So. So this may well happen.

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It won't happen as quickly as they would like and even as quickly as they would like.

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It doesn't happen that quickly. The limits in China to doing things are not necessarily having the money because their political system

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doesn't have quite the same links between government budgets and and know balanced budgets and so forth.

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But their expertise, there aren't enough accelerator scientists in China to do this.

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There aren't enough particle physicists in China to do this. There aren't enough technical people to design this.

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So those are what slows down their delivery of big telescope projects.

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That delivery of aspiration, neutron source, the delivery of the Shanghai Synchrotron,

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and those would be squared or cubed in difficulty for something like this.

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So if this is to happen, it will have to happen as an international project.

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And that's a very interesting possibility for the 2020s.

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For example, if we if it if it does gain traction. We shall see.

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Now there's a ritual slide that has to be shown at this point,

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which is to point out that all of the particle accelerators that I've talked about so far go back to the 1950s or sixties.

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They're using radio frequency energy to accelerate charged particles in an electromagnetic cavity.

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You can accelerate particles using light in a plasma cavity, or you can use a laser beam to excite very small cavities in ways that,

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you know, don't depend on on basically Second World War vacuum tube technology, which is still what we're using.

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And so if you visit Berkeley, Wim Lehman's will show you.

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[INAUDIBLE] say this is a particle accelerator. It fits in the palm of your hand.

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You can get a GeV of energy out to that. Well, you know, he says he takes 100 metres of accelerator to get a GeV of energy.

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Isn't that great? And then you go upstairs and you find he's got 100 metres of laser.

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So it's not so obvious to me that this is the right way to go.

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It may well be. It does have a little bit of the nuclear fusion into it that it's always a few decades into the future.

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So the future Circular Collider that's being sketched out for CERN does not depend on this.

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The IOC does not depend on this. If somebody can make this work. Let's build an x ray light source like diamond.

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But it would fit in this room. And that would really demonstrate that the technology has arrived.

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And there's a lot more places in the world that would give you money for an x ray light source, especially if it fit within this room.

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So so I think this is technology with lots of applications, but it just may not be forefront particle physics technology yet.

389
00:38:44,590 --> 00:38:55,540
Now, I've talked a lot about Higgs and supersymmetry, and I've also admitted that we haven't found anything beyond the Higgs.

390
00:38:56,470 --> 00:39:02,560
So it's quite possible that we are, as the proverb says, in a dark room, searching for a black cat that isn't there.

391
00:39:03,490 --> 00:39:08,049
We have to. It's a long way to go from absence of evidence to evidence of absence.

392
00:39:08,050 --> 00:39:13,720
And we're not there yet. But after a couple of decades of running a the Large Hadron Collider and not finding anything,

393
00:39:13,720 --> 00:39:20,270
I think most physicists will be in a position to say in ten years time, maybe this other stuff really isn't there.

394
00:39:20,290 --> 00:39:24,160
It's not just that a little bit higher energy or a little bit rarer to produce than we had thought.

395
00:39:24,850 --> 00:39:32,890
And so that means we should also look for the other things that have come along and surprised us in the last few years.

396
00:39:33,280 --> 00:39:41,830
The Higgs is clearly the pillar on which particle physics is based right now, and the Large Hadron Collider is the centrepiece of that program.

397
00:39:42,040 --> 00:39:46,060
But it mustn't be the whole program because in the end there may not be a cat in the dark room.

398
00:39:47,650 --> 00:39:54,190
Let me just take a little aside into metaphysics here, because if there is no cat in the dark room, if the Higgs is all there is,

399
00:39:54,520 --> 00:39:59,440
we haven't solved those problems about why is its mass finite and what does it have to do with the universe.

400
00:39:59,740 --> 00:40:02,190
It may be that we discover some other things through other routes,

401
00:40:02,440 --> 00:40:10,420
but there is the rather scary possibility that we just live in a universe which is technically speaking, fine tuned.

402
00:40:10,960 --> 00:40:15,370
And that means that the coupling constants of certain things just happen to cancel each other out.

403
00:40:16,210 --> 00:40:21,520
And if you want to believe in God, you could believe that God set the world up this way so that that works.

404
00:40:21,520 --> 00:40:26,890
Because if it was not set up that way, like I said, we'd be living in a universe the size of a grapefruit or no universe at all.

405
00:40:27,460 --> 00:40:34,630
So for our universe to exist, it appears that there either has to be physics that we don't know about to make the corrections balance,

406
00:40:34,630 --> 00:40:44,290
or there has to be some fiendishly precise one in 10 to 120 fine tuning between the various coupling constants so that the the

407
00:40:44,290 --> 00:40:49,780
curling up of spacetime due to the Higgs is exactly cancelled by a cosmological constant of equal and opposite magnitude,

408
00:40:49,930 --> 00:40:53,350
for example. That's not a particularly attractive proposition,

409
00:40:53,680 --> 00:41:03,759
but it may be that there is some physics behind that because some of the string theories which attempt to describe the fundamental

410
00:41:03,760 --> 00:41:10,240
basis of the entire universe and why a universe exists and how it could have expanded so rapidly when it was very young,

411
00:41:10,780 --> 00:41:20,260
predict that there is, in fact an almost infinite number of universes with randomly selected coupling constants and and fundamental forces in them,

412
00:41:21,280 --> 00:41:27,339
so that it could just be that we are in one of an infinite number of universes and of course

413
00:41:27,340 --> 00:41:30,640
we're in the one where the coupling constants are fine tuned because in all the others,

414
00:41:30,940 --> 00:41:38,200
the typical universe, there is no life, there is no stars, there are no planets, there's no quarks, there's no W boson, there's just nothing at all.

415
00:41:38,410 --> 00:41:43,510
So that's depressing because it's fundamentally untestable, I think.

416
00:41:43,540 --> 00:41:51,849
I'm not sure this is science. There might be ways you could verify this was true, because if the number of universes isn't completely infinite,

417
00:41:51,850 --> 00:41:56,469
the amount of fine tuning shouldn't be arbitrarily large. But it is an interesting possibility.

418
00:41:56,470 --> 00:42:01,870
And you will hear talks. You can have one next year about the string, the multiverse, and it will blow your mind.

419
00:42:01,990 --> 00:42:06,820
But in the end, it's not science at this point. But that may well be where we are if we're in a back room without a.

420
00:42:07,990 --> 00:42:12,700
So I don't like that outcome, so I don't like the fine tuning. So let's try and do some science instead.

421
00:42:13,660 --> 00:42:18,970
So the Higgs was the last piece of 20th century particle physics in some profound sense.

422
00:42:19,420 --> 00:42:27,309
It completed a line of inquiry that came from Feynman and quantum electrodynamics and

423
00:42:27,310 --> 00:42:32,200
Renormalisation theory and trying to understand how to make quantum mechanics calculable.

424
00:42:32,290 --> 00:42:42,640
In the 1940s, mathematical consistency, normalised ability, inherent self consistency among the equations you don't want divergences.

425
00:42:42,820 --> 00:42:47,050
In fact, that's what led to the invention of quantum mechanics to solve divergences in classical mechanics.

426
00:42:47,470 --> 00:42:51,590
So the Higgs draws a line under that, but it doesn't tell you anything else.

427
00:42:51,620 --> 00:42:54,730
We haven't found anything else associated with it, at least so far.

428
00:42:54,880 --> 00:42:57,190
So there are no more guaranteed discoveries.

429
00:42:57,520 --> 00:43:03,010
The Higgs was a discovery of whether it existed or not, because the absence of a Higgs was it would have been a bigger discovery than the presence.

430
00:43:03,310 --> 00:43:08,200
But there are no more, and many key questions remain to be answered. So sorry to all theoretical colleagues.

431
00:43:08,200 --> 00:43:16,400
Your guidance is always welcome, but at this point we need to find some more data and some more experiments that we can do.

432
00:43:16,420 --> 00:43:20,060
And that means we need to look outside the realm of the LHC.

433
00:43:20,440 --> 00:43:23,829
And so I'll briefly cover a couple of areas where we are looking and where Oxford

434
00:43:23,830 --> 00:43:28,480
is looking that we have discovered things that don't fit on John Ellis's T-shirt.

435
00:43:29,020 --> 00:43:33,520
And that's that's what I mean by physics outside the standard model. So the first one of these is neutrinos.

436
00:43:33,520 --> 00:43:44,620
Now neutrinos. The neutrino was postulated in the 1930s by Pauli as a product of radioactivity to decay,

437
00:43:44,620 --> 00:43:51,099
along with the electron to maintain what looked like a violation of the

438
00:43:51,100 --> 00:43:57,370
conservation of energy when a radioactive nucleus decayed through beta radiation.

439
00:43:57,460 --> 00:44:00,370
The electron carries off some of the energy, but not all of it.

440
00:44:00,760 --> 00:44:06,430
And you could either assume that energy conservation was violated in quantum mechanics, and that was a serious possibility at that time,

441
00:44:06,610 --> 00:44:10,390
because quantum mechanics wasn't understood at the level that it was and partly pointed out, no,

442
00:44:10,480 --> 00:44:19,510
you can maintain kinematics and energy conservation and momentum conservation if you propose the existence of a massless and in his view,

443
00:44:19,510 --> 00:44:26,680
not interacting particle that is also produced along with the electron is not totally non interacting, otherwise we wouldn't be talking about it.

444
00:44:26,980 --> 00:44:32,469
It turns out the since it is produced in a decay, it can be captured in the inverse reaction to that decay.

445
00:44:32,470 --> 00:44:40,900
And indeed it is. So we know neutrinos exist and they were directly discovered in the 1950s and we can produce them and understand their properties.

446
00:44:42,010 --> 00:44:51,069
It turns out relatively recently, as you will see upstairs from the snow experiment, that neutrinos are not such simple things as Pauli.

447
00:44:51,070 --> 00:44:54,160
And we thought there are different kinds of them.

448
00:44:54,160 --> 00:44:56,469
And when they travel over long distances,

449
00:44:56,470 --> 00:45:02,950
much longer than the distances within a laboratory or within your experiment from the beta radiator to the detector,

450
00:45:03,160 --> 00:45:10,930
when that's hundreds of kilometres of travel, the three kinds of neutrinos undergo a quantum mechanical oscillation from one kind to another.

451
00:45:10,930 --> 00:45:12,220
And what you make isn't what you get.

452
00:45:12,850 --> 00:45:19,660
You leave Geneva with Swiss francs in your pocket and you arrive in London and they've turned into a mixture of pounds and Danish krona.

453
00:45:20,320 --> 00:45:25,000
And in the macro world, that doesn't work. Well, you do what you said it did for you once.

454
00:45:25,180 --> 00:45:31,030
But in the quantum mechanical world, that happens because the mass eigen states are not the same as the flavour eigen states.

455
00:45:31,030 --> 00:45:36,940
And if you don't understand what I just said, don't worry. If you do, that's the the most concise explanation.

456
00:45:37,480 --> 00:45:41,799
So this is of interest not just because it's physics that doesn't fit on John Ellis's T-shirt.

457
00:45:41,800 --> 00:45:42,910
And it might point somewhere,

458
00:45:43,360 --> 00:45:52,630
but also because the oscillations between these three kinds of neutrinos may in principle have a large asymmetry between matter and antimatter.

459
00:45:52,990 --> 00:45:55,840
And that is a little bit of a holy grail for scientists,

460
00:45:55,840 --> 00:46:01,840
because we know that our universe is largely full of matter, or at least the close by universe is full of matter.

461
00:46:01,990 --> 00:46:05,590
And we don't see any gamma radiation from distant sources,

462
00:46:05,590 --> 00:46:10,300
which would imply that there's any annihilation between matter and anti-matter going on anywhere else in the universe.

463
00:46:10,570 --> 00:46:17,200
So while we don't know for sure, it looks as if the matter in the universe is matter and not an equal mix of matter and antimatter.

464
00:46:17,380 --> 00:46:22,810
But in any process, like the Big Bang, one should produce equal amounts of matter and antimatter.

465
00:46:23,050 --> 00:46:26,830
And therefore something has happened to violate this symmetry either in the production or

466
00:46:26,830 --> 00:46:31,870
in the subsequent interaction and decay and neutrinos might be a link to such things,

467
00:46:31,870 --> 00:46:38,919
though it's all very sketchy at this point, and nobody can quite explain in total detail how that could lead to a universe with with stuff in it,

468
00:46:38,920 --> 00:46:44,050
and not an equal mixture of stuff and anti stuff. Nonetheless, it's an extremely intriguing possibility.

469
00:46:44,560 --> 00:46:49,629
So just as there are large plans to explore the Higgs,

470
00:46:49,630 --> 00:46:58,030
there are large plans to explore the properties of neutrinos over the kind of distances that allow this oscillation from one kind of neutrino to

471
00:46:58,030 --> 00:47:05,950
another to fully play out and would allow the the differences between their interaction with matter and anti-matter to become fully apparent.

472
00:47:06,700 --> 00:47:10,540
And to do that, you need to produce an intense beam of neutrinos. Let it travel through the earth.

473
00:47:10,790 --> 00:47:16,629
Doesn't matter. You don't need to dig a tunnel. They will not interact significantly, sufficiently,

474
00:47:16,630 --> 00:47:23,430
significantly to lose the intensity that you need and detect the neutrinos at a location of your choosing.

475
00:47:23,890 --> 00:47:34,060
And so what is proposed in the United States is to start at Fermilab, where just to the northwest of Chicago here,

476
00:47:34,060 --> 00:47:38,139
where the neutrinos will be produced and they will be shot downwards at a certain angle.

477
00:47:38,140 --> 00:47:40,390
Because if you think about it, the earth is a sphere.

478
00:47:40,570 --> 00:47:46,270
And therefore, in order to to reach South Dakota, they have to be directed downwards a little bit.

479
00:47:46,540 --> 00:47:51,610
They will travel under the earth for about a thousand kilometres and emerge, will not emerge.

480
00:47:52,360 --> 00:48:00,040
Intersect a mine. The Homestake Gold mine, which is no longer a gold mine, has been.

481
00:48:02,110 --> 00:48:05,740
Care taken by the state of South Dakota as a future physics laboratory.

482
00:48:06,370 --> 00:48:13,060
And in that location there will be constructed if money is voted by Congress,

483
00:48:13,630 --> 00:48:18,370
a very large set of caverns which are shown here about a mile underground,

484
00:48:18,790 --> 00:48:26,020
which will include very large tanks with something like 50,000 tons of liquid argon.

485
00:48:26,590 --> 00:48:30,459
And the beam of neutrinos will be coming this way. And every now and then,

486
00:48:30,460 --> 00:48:37,390
one in a billion or something of those neutrinos will interact with an outgoing atom in these tanks and will produce ionisation,

487
00:48:37,390 --> 00:48:45,970
and the ionisation will be drifted onto cathodes. And from that will scientists will be able to infer what kind of neutrinos have arrived,

488
00:48:46,120 --> 00:48:51,159
the rate at which they've arrived, and the energy that they are carrying. Now, this looks all very clinical, doesn't it?

489
00:48:51,160 --> 00:48:55,540
It looks like like you could just, you know, draw that.

490
00:48:56,170 --> 00:49:00,320
But in actual fact, a mile underground in a gold mine isn't clinical.

491
00:49:00,370 --> 00:49:11,799
It's it's a dangerous big environment. And the plan here is to dig out 100,000 tons of this rock in a few years on a conveyor

492
00:49:11,800 --> 00:49:17,230
belt out the side of that mountain and dump it in a what used to be a settling pond,

493
00:49:17,230 --> 00:49:19,090
for it is a god awfully polluted place.

494
00:49:19,090 --> 00:49:26,500
So there's not too much worry as there might be around here at filling up a gravel pit with 100,000 tons of rock.

495
00:49:27,220 --> 00:49:32,470
And that cavern has to be excavated safely, of course, and then it will be filled with detectors.

496
00:49:32,470 --> 00:49:37,420
And so this is a prototype of one of those much smaller than what will eventually be built.

497
00:49:37,420 --> 00:49:42,579
You can see copper wire planes onto which the charge will be collected.

498
00:49:42,580 --> 00:49:48,700
And this is a neutrino interaction here. Neutrinos come in, hit a nucleus and produced ionising radiation,

499
00:49:48,700 --> 00:49:56,860
which is how you detect if there is a similar project under discussion slash close to approval in Japan.

500
00:49:57,490 --> 00:50:03,910
And so what we are seeing now is something like a global coordination of particle physics projects

501
00:50:03,910 --> 00:50:09,670
appearing where both Asia and North America are contributing to a Large Hadron Collider at CERN.

502
00:50:09,910 --> 00:50:15,010
And there are going to be contributions from universities and laboratories in Europe to both of these programs.

503
00:50:15,010 --> 00:50:21,790
So that will be a rather nice international complementarity rather than everybody trying to do exactly the same thing.

504
00:50:21,970 --> 00:50:25,120
And I should say there are good science reasons why you would want both this and this.

505
00:50:26,560 --> 00:50:33,760
Now, the other place where new stuff has happened is the cosmos astroparticle physics or particle astrophysics,

506
00:50:33,760 --> 00:50:39,280
or the discovery of hints about the fundamental equations of the universe,

507
00:50:39,280 --> 00:50:46,570
not from experiments in colliders, but from the the signals that come from very distant stars and galaxies,

508
00:50:46,810 --> 00:50:51,850
or from high energy particles impinging on the earth from from distant events.

509
00:50:52,240 --> 00:50:55,480
So this is the Planck satellite, which was launched by the European Space Agency,

510
00:50:55,630 --> 00:51:01,270
superimposed on a map of the cosmic microwave background radiation in the universe.

511
00:51:01,270 --> 00:51:10,599
So that's the surface of our scattering when photons were able to propagate freely after about one hour when the universe was 100,000 years old.

512
00:51:10,600 --> 00:51:14,320
Something like that. 300,000 years. Okay, order of magnitude estimates.

513
00:51:15,100 --> 00:51:18,340
So that is as far back in time as one can see.

514
00:51:18,850 --> 00:51:22,200
And it is not uniform as the colour indication here is supposed to.

515
00:51:22,220 --> 00:51:25,300
It would be uniform if you showed it in true temperature.

516
00:51:25,540 --> 00:51:30,370
That is the temperature of universe and the small fluctuations in that are what

517
00:51:30,400 --> 00:51:35,140
seeded and grew to form the galaxies and large scale structure that we now see.

518
00:51:35,530 --> 00:51:43,360
And you can look at the multiple moments, odia technical word again, you can look at the angular distribution of those fluctuations.

519
00:51:43,510 --> 00:51:50,049
And if there are a lot of very short wavelength fluctuations, you'll get a lot of very large multiplying numbers here.

520
00:51:50,050 --> 00:51:55,390
If there's if there is a dipole, big dipole fluctuation, you'll get something at the peak of two and you see there is a dipole.

521
00:51:55,390 --> 00:51:58,450
And that's to do with the earth moving through this field.

522
00:51:59,020 --> 00:52:02,050
But the exact structure to this is a predictable thing.

523
00:52:02,440 --> 00:52:11,170
And what it tells you is that the universe is full of stuff that isn't protons, neutrons or again on John Ellis's t shirt.

524
00:52:11,830 --> 00:52:20,440
And we capture the behaviour of that stuff by dividing it into two categories the stuff which looks like particles of matter,

525
00:52:20,440 --> 00:52:28,870
and we call that dark matter, it appears to be neutral, weakly interacting, clumpy, so not relativistic.

526
00:52:29,110 --> 00:52:31,540
But beyond that we don't know a huge amount about it.

527
00:52:31,540 --> 00:52:39,729
And it appears that from our astrology, astronomy, astrophysics, colleagues, most galaxies, probably including ours, have a lot of this stuff in them.

528
00:52:39,730 --> 00:52:47,830
And it may well be that the stars, planets and stuff that's made of material like us is just a little dressing on top of a dark matter structure,

529
00:52:47,830 --> 00:52:48,940
which is really what we're seeing.

530
00:52:49,720 --> 00:52:58,270
The other 90 though, sorry, the other 70% of the universe or the mass energy in the universe appears to be something much more mysterious,

531
00:52:58,510 --> 00:53:08,220
which we call dark energy. And that. Is a quantum mechanical field which appeals appears to pervade the universe with a sort of expansionism,

532
00:53:08,400 --> 00:53:13,320
an expanding attention to it, driving the universe to grow.

533
00:53:14,040 --> 00:53:21,750
And that is so. So you can have a seminar where they come up with a long list of plausible candidates for what dark matter might be.

534
00:53:22,170 --> 00:53:26,640
And then the next slide will be plausible candidates for what dark energy might be, and it's usually empty.

535
00:53:27,930 --> 00:53:31,680
So the combination of these two shouldn't really be lumped together.

536
00:53:31,680 --> 00:53:36,810
I think dark matter is something that we can understand as eventually it will have to fit on John Ellison's t shirt.

537
00:53:37,260 --> 00:53:45,750
Dark energy may be something much more to do with Do we understand Einstein in relativity at the level that we think we do?

538
00:53:45,990 --> 00:53:51,780
Is there a cosmological constant? There are experiments going on to see if there's been any change over the

539
00:53:51,780 --> 00:53:55,590
lifetime of the universe to the amount of dark energy that there appears to be,

540
00:53:55,710 --> 00:53:58,800
because that could tell us rather interesting things about whether it is indeed

541
00:53:58,800 --> 00:54:06,900
a property of space time or whether it's something filling the universe, but not a subject for today, except to note that the normal part of this,

542
00:54:07,500 --> 00:54:13,350
the dark matter part of this is something we can and should look for in experiments here.

543
00:54:13,530 --> 00:54:18,780
And indeed, snow is part of the the toolkit to do that.

544
00:54:19,380 --> 00:54:26,010
So I'm just going to show you a project which is relatively new in which the UK is getting involved in called like Zeppelin.

545
00:54:26,130 --> 00:54:36,630
It happens to be going to be located in this same location in South Dakota and the excavation for Elzey has already taken place.

546
00:54:36,930 --> 00:54:40,559
And as you can see, it's a cavern about the size of this lecture theatre.

547
00:54:40,560 --> 00:54:45,900
Maybe double the height which has been blasted out to the rock is the mining

548
00:54:45,900 --> 00:54:49,920
people like this rock is how it stands up without needing to be supported.

549
00:54:50,130 --> 00:54:55,620
But it is difficult to excavate in and in a few years time that cavern will be filled.

550
00:54:55,620 --> 00:54:57,000
This is approximately to scale.

551
00:54:57,270 --> 00:55:07,799
Cavern will be filled with this experiment which will place a very large vessel of liquid xenon in the middle and surround it with photo

552
00:55:07,800 --> 00:55:17,010
multiplier tubes that will detect flashes of scintillation light and drift the charge on to enable you to collect the charge as well.

553
00:55:17,190 --> 00:55:25,500
So this will be as the earth drifts around the sun or and as the solar system drifts around the centre of our galaxy,

554
00:55:25,950 --> 00:55:36,060
we will be slowly passing through a cloud of dark matter, which is part of the galaxy, like the stars and and gas clouds and everything else.

555
00:55:36,510 --> 00:55:45,060
And so this experiment should just slowly pick up dark matter particles as the earth moves through them, a wind of dark matter.

556
00:55:45,390 --> 00:55:54,090
And every time it does, every time one of them happens to interact elastically with a xenon nucleus,

557
00:55:54,240 --> 00:55:59,700
we should see a little flash of scintillation light in this detector. So what gives you the sensitivity here is the very large volume.

558
00:56:00,000 --> 00:56:03,630
This technology has been used on a smaller scale and we know it works.

559
00:56:04,350 --> 00:56:09,660
We know that dark matter exists. But this is a little bit of a shot in the dark, if you pardon the pun,

560
00:56:09,900 --> 00:56:16,350
because we don't know for sure that the mass of the particles is such that they will be detected in in this experiment.

561
00:56:16,680 --> 00:56:21,210
And I should link back to the Superman logo here, because in supersymmetric models,

562
00:56:21,390 --> 00:56:27,030
one of the new particles that is predicted is a perfect candidate to be this dark matter that

563
00:56:27,420 --> 00:56:30,749
with about the right density and about the right properties that we'd expect in the universe.

564
00:56:30,750 --> 00:56:32,880
So it would be really, really neat if that was true.

565
00:56:33,180 --> 00:56:38,370
But the universe doesn't make things happen just because they'd be really, really neat for a bunch of people in the 21st century.

566
00:56:38,610 --> 00:56:42,909
So it may well have been done differently, but it would be neat if that turned out to be the case.

567
00:56:42,910 --> 00:56:50,010
We should also just say another thing which is new, but which I'm not going to say any much more about is new.

568
00:56:50,010 --> 00:56:54,600
Ways of looking at the universe are also opening up so early.

569
00:56:54,900 --> 00:56:55,680
About a year ago,

570
00:56:55,680 --> 00:57:03,870
you will have heard of the discovery of gravitational waves from a collision between two black holes in a galaxy about 1.3 billion light years away.

571
00:57:04,230 --> 00:57:11,460
This is a computer simulation of the waves of gravitational energy that would radiate out from such a collision.

572
00:57:11,700 --> 00:57:17,099
And the little traces here show what was actually measured in precision detectors located

573
00:57:17,100 --> 00:57:22,020
in the United States when that wave of gravitational disturbance went through the earth.

574
00:57:22,020 --> 00:57:25,380
So, you know, real life disturbance in the force from from Star Wars,

575
00:57:25,620 --> 00:57:33,270
but picked up with a laser interferometer that can measure pico metre separations in two mirrors that are a couple of kilometres apart.

576
00:57:33,630 --> 00:57:41,730
So this is a new way that we will be able to look at the universe and we will be able to start doing astronomy

577
00:57:41,970 --> 00:57:47,100
with gravitational waves in the sense that we can pinpoint the direction that these things came from.

578
00:57:47,370 --> 00:57:51,299
When some additional instrumentation comes online in a couple of years time,

579
00:57:51,300 --> 00:57:56,490
you'll be able to triangulate the direction that the waves are coming from, and that will be interesting and potentially important.

580
00:57:57,480 --> 00:58:00,960
So how much time do I have in you have about 5 minutes. Right.

581
00:58:01,050 --> 00:58:07,080
So. I'm going to zip very, very quickly through some of those points you made about the need to explain and justify what we are doing.

582
00:58:08,280 --> 00:58:16,680
The broader context in which we operate. So one of the reasons I got interested in science policy was the observation that this can go wrong.

583
00:58:17,400 --> 00:58:23,729
This was a beautiful project in Texas, the superconducting supercollider, which would have,

584
00:58:23,730 --> 00:58:27,690
if completed, discovered the Higgs about ten years before CERN eventually did.

585
00:58:27,990 --> 00:58:36,180
But it didn't discover the Higgs because it's now filled in and was cancelled about three years after after excavation started.

586
00:58:36,600 --> 00:58:42,360
So, you know, when you interact with with government, you have to understand why they want to support science.

587
00:58:42,690 --> 00:58:48,930
And they do recognise, I think even at really relatively high levels, that our prosperity depends upon science.

588
00:58:49,230 --> 00:58:56,220
There's a market failure because most business likes to do relatively incremental improvements.

589
00:58:56,670 --> 00:59:01,470
What we have to do then as science is do stuff that isn't incremental, that's potentially transformative.

590
00:59:01,680 --> 00:59:06,930
I should say there have been some shining examples in the past of businesses that did support transformative R&D.

591
00:59:07,200 --> 00:59:10,320
Bell Labs with the transistor, for example,

592
00:59:10,410 --> 00:59:16,530
the invention of the laser and maybe Google now with artificial intelligence is doing stuff that they don't see market value for.

593
00:59:16,680 --> 00:59:18,360
But the pay offs are long term and uncertain.

594
00:59:18,900 --> 00:59:24,120
So here's a scientist doing science, and what she wants to do most of the time is understand the universe.

595
00:59:24,120 --> 00:59:28,229
And I've just talked for an hour about that. We take money to do that.

596
00:59:28,230 --> 00:59:31,590
And money comes from governments, and I'm not sure whether any will come from this particular one.

597
00:59:31,600 --> 00:59:43,770
We shall see. Government tends to be motivated at some level by understanding the universe because they are usually educated people,

598
00:59:43,780 --> 00:59:45,760
usually more educated than we give them credit for.

599
00:59:46,240 --> 00:59:57,670
But they really like the technological innovation and skills that feels like particle physics can deliver because we can do things that push science.

600
00:59:57,730 --> 01:00:00,970
Sorry, but we can do science that pushes technology.

601
01:00:01,330 --> 01:00:04,840
Big science in astronomy and nuclear physics has the same thing.

602
01:00:05,110 --> 01:00:11,050
So why don't you know if it's if science delivers the solutions to big challenges,

603
01:00:11,290 --> 01:00:16,210
why shouldn't we direct all of our resources to work on big challenges like renewable energy?

604
01:00:16,360 --> 01:00:21,309
And the answer is that doesn't excite young people in the same way that particle physics does.

605
01:00:21,310 --> 01:00:24,400
Apologies to anyone in the audience who is now working on renewable energy.

606
01:00:24,850 --> 01:00:31,030
But we have good evidence from from surveys of students that fundamental research attracts

607
01:00:31,030 --> 01:00:35,530
young people into science in much greater numbers and drives technological innovation.

608
01:00:35,530 --> 01:00:39,099
So how much does it days? He always says, Oh, John, you are not selling the stake.

609
01:00:39,100 --> 01:00:47,140
You are selling the sizzle. This was a legendary advertising campaign in the United States, and I guess the sixties were selling the spinoffs.

610
01:00:47,470 --> 01:00:55,990
And so when the Higgs was discovered, CFC supported an exhibition at the Science Museum and made sure that this guy was invited.

611
01:00:55,990 --> 01:00:58,420
George Osborne, who was, of course, the source of money.

612
01:00:58,420 --> 01:01:04,870
At that point, we made sure that the Large Hadron Collider was plastered over the front of the BIS office building in London,

613
01:01:04,870 --> 01:01:10,000
so the civil servants who were paying for this would see that their money had gone on, something they could be proud of.

614
01:01:10,150 --> 01:01:14,830
And we made sure that it was highlighted by foreign direct investment programmes.

615
01:01:15,340 --> 01:01:22,120
There's been a significant increase in the number of students studying physics in undergraduate courses,

616
01:01:22,870 --> 01:01:26,740
not all entirely due to Brian Cox over the Large Hadron Collider, but.

617
01:01:26,830 --> 01:01:33,880
But some of it is to do with the greater visibility that the physical sciences have had in the fundamental physics to do with the Higgs.

618
01:01:34,150 --> 01:01:35,650
And I think that's something very important.

619
01:01:35,820 --> 01:01:43,540
We should also remember that long before the Higgs was discovered, the tools that were needed to do so transformed all of our lives.

620
01:01:44,350 --> 01:01:47,930
So Tim Berners-Lee, with his proposal for information management.

621
01:01:47,950 --> 01:01:52,659
Vague but exciting as it was famously reviewed, went on to be the World Wide Web.

622
01:01:52,660 --> 01:01:55,900
And, you know, you used it to find out how the traffic was coming here.

623
01:01:56,140 --> 01:02:02,260
So we can't claim credit for the entire global economy as a spin off of particle physics,

624
01:02:02,470 --> 01:02:09,940
but it has changed the entire global economy, and that's something that we should never stop talking about, albeit slightly humbly.

625
01:02:11,170 --> 01:02:13,420
Another example, which you may not be so familiar with,

626
01:02:13,630 --> 01:02:22,690
is that research into look at looking for radiation from black holes at the Commonwealth Science and Industry Research Organisation in Australia.

627
01:02:22,690 --> 01:02:26,950
This is one of their radio telescopes led to patents which are incorporated in the wi fi chipset.

628
01:02:27,250 --> 01:02:37,510
So CSIRO receives about $200 million a year in royalties from wi fi patents, which is pretty good as a demonstration that radio astronomy has,

629
01:02:38,140 --> 01:02:42,730
you know, transformed the way that we communicate because there's a real monetary value associated with it.

630
01:02:42,730 --> 01:02:47,140
And the fact that companies pay to use it shows the value in ways that are much more than hardware.

631
01:02:48,250 --> 01:02:54,370
I once did a estimate of the impact of the Tevatron accelerator, where I had worked for for many years,

632
01:02:54,610 --> 01:02:59,710
and we concluded on the back of an envelope that there was something like a ten times payoff

633
01:02:59,920 --> 01:03:04,780
to US society from the investment that had gone into into this machine over its lifetime.

634
01:03:05,020 --> 01:03:12,999
And one example of that, which comes back to the magnet technologies, the Tevatron was the first large scale installation of superconducting magnets.

635
01:03:13,000 --> 01:03:19,629
It's a national engineering landmark in the United States because of that that led to is documented

636
01:03:19,630 --> 01:03:23,530
that that led to the adoption of superconducting magnet technology by companies like GE.

637
01:03:23,530 --> 01:03:28,899
For MRI scanners, the MRI industry is worth about $5 billion per year.

638
01:03:28,900 --> 01:03:33,760
I forget if that's within the US or worldwide, but you shouldn't even think about that as the pay off.

639
01:03:33,760 --> 01:03:38,049
You should think about the improved health outcomes that have come from the widespread use of these machines,

640
01:03:38,050 --> 01:03:43,090
all the days of work that aren't taken and the longer life that's been contributed to society.

641
01:03:44,170 --> 01:03:49,120
So I think I'm about to conclude the future of particle physics.

642
01:03:49,480 --> 01:03:53,559
Well, the first message is that it's different than we thought it was a few years ago,

643
01:03:53,560 --> 01:03:56,950
and that's great, because if it was the same, it wouldn't be the future.

644
01:03:57,580 --> 01:04:02,950
It will be driven by experimental discoveries. The science goals behind those discoveries are clear.

645
01:04:03,100 --> 01:04:09,909
We found the Higgs. We know we need to understand the properties of neutrinos in detail, and we know we need to explore these cosmic connections.

646
01:04:09,910 --> 01:04:17,110
What's behind Darth Vader's helmet is the dark matter that seems to make up a lot of the universe connected to two models of equations or not.

647
01:04:17,680 --> 01:04:21,250
A global strategy for the toolkit to do this is emerging.

648
01:04:21,670 --> 01:04:23,860
It's anchored by the Large Hadron Collider.

649
01:04:24,010 --> 01:04:29,589
There's been a huge investment in that machine, and it's still delivering front cross science with substantial upgrades.

650
01:04:29,590 --> 01:04:33,670
And we know how to do that. We know the technologies that are needed a neutrino.

651
01:04:33,900 --> 01:04:39,480
Program with long baseline experiments using particle accelerators to shoot beams of neutrinos at underground detectors,

652
01:04:39,690 --> 01:04:42,690
which will enable us to explore whether this is to do with the matter.

653
01:04:42,690 --> 01:04:47,610
Antimatter asymmetry in the universe, and I should say nothing at the LHC has pointed in that direction.

654
01:04:47,610 --> 01:04:51,809
So it's really quite important that we we we follow up on this and it's also important

655
01:04:51,810 --> 01:04:56,219
that we follow up on these astroparticle connections connecting the particle

656
01:04:56,220 --> 01:04:59,640
physics done in accelerator laboratories with what we know about the universe

657
01:04:59,640 --> 01:05:04,630
from astronomy and astrophysics and exploit new hints like gravitational waves.

658
01:05:04,650 --> 01:05:10,350
New ways of looking at the universe that we sit in. And there is no shortage of ambitious ideas for the future.

659
01:05:10,650 --> 01:05:15,480
As I've said, a typical issue there is getting the costs down to the affordable level.

660
01:05:15,750 --> 01:05:20,940
And in many cases there's some technology R&D that we need to do anyway, which is well worth pursuing.

661
01:05:21,540 --> 01:05:26,730
Challenges are technological but also political, and as Ian hinted at the beginning,

662
01:05:27,450 --> 01:05:33,630
there are ways that people can help, not just those who might be in a position to to down student ships and so forth.

663
01:05:33,780 --> 01:05:39,600
But all of you, in talking about the excitement and interest that this field has, the progress that it's making,

664
01:05:39,840 --> 01:05:45,360
and the arguments that I've I've outlined about the value in terms of technology and skills to the economy.

665
01:05:45,510 --> 01:05:46,650
So thank you all very much.