The Infinite Monkey Cage - The Fundamentals of Reality

Episode Date: February 8, 2021

The Fundamentals of RealityBrian Cox and Robin Ince are joined by Nobel prize-winning physicist Frank Wilczek, cosmologist Janna Levin, and comedians Eric Idle and Sara Pascoe to look at what physics has revealed about the reality of our universe. From Einstein's equations more than 100 years ago through to the amazing discoveries we've made in the last few years about black holes and gravitational waves, the universe we think we see is not necessarily the true fundamental reality that physics has uncovered. What is real and what is not? All will be revealed.Producer: Alexandra Feachem

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to go up. Know your risks. Visit heartandstroke.ca. BBC Sounds. Music, radio, podcasts. Hello, I'm Brian Cox. I'm Robin Ince. And this is the Infinite Monkey Cage. And today we are talking about reality. There are those who say that life is an illusion and that reality is but a figment of the imagination. Is there such a thing as a real underlying reality or does everyone's opinion have equal validity, as is clearly stated in Twitter's terms of service? For instance, Brian might say... E equals MC squared. And I might say, yeah, yeah, well, that's just your opinion.

To which you might reply... It's not opinion. that's just your opinion. To which you might reply... It's not opinion. It's not an opinion. The equation follows if you accept the laws of physics should be expressible as coordinate, independent, and reference frame independent relationships between geometrical objects representing physical quantities or entities, and that the

appropriate geometrical arena is Minkowski spacetime and that the energy momentum four vector is one such geometrical object. And I would then reply, fake physics. I don't even believe that energy and matter actually exist. I think they're merely something used by the Illuminati and other snake-headed scientists. And then this would continue for 28 hours

until one or other was destroyed by a lack of logic. Anyway, today to debate the nature of reality, we're joined by a Nobel Prize winning physicist, an expert on black holes, a globe-trotting comedian and the lead reporter for Rutland Weekend Television. And they are... I'm Frank Wilczek, I'm a professor at MIT. I won the Nobel Prize for Physics in 2004. I've written a book that's just coming out called Fundamentals that can bring you joy and expand your mind, so go get it. And the thing I find most difficult to understand about reality is how I'm part of it. I'm Jana Levin, and I'm an astrophysicist, theoretical physicist, and an author, most recently of Black Hole Survival

Guide, I think the aspect of reality I find hardest to fathom is that we can fathom reality at all, especially the aspects beyond our immediate senses. And I think that's unusual enough that it impels us to search for other life out there with similar capacities. other life out there with similar capacities. My name's Sarah Pascoe. I'm a comedian, which is a bit of a drop in achievements. And the part of reality that I find difficult to fathom is that I can't trust any of it. I'm being gaslit by the entire world, including my own senses.

Hi, my name is Eric Idle. I'm a comedy writer and I believe reality is overrated. And this is ourrated. So let's start off with a definition. And we always like to do definitions, but this one might be a tougher one and might actually cover the whole of the show. And that is what is the definition of reality? What is reality? Frank, starting with you. Well, reality is several things, but maybe the two most important versions of reality, I think, for most people are as babies, we're suddenly exposed to a sensory universe that needs to be organized so that we can survive and get around. And so we invent rules of thumb,

that there are objects in three-dimensional space that have more or less predictable properties, and we construct a world on that basis. Then, if we become curious adults, we realize that there are many other ways to interrogate the physical world with telescopes and microscopes and spectrometers and magnetometers and all kinds of other instruments, and to think about it in more logical, critical, organized ways. And we find a different version of reality that is also coherent, that also describes huge aspects of our experience that are uncovered if we use those instruments and use all our mind. And those, to me, are the two most interesting versions of reality, sort of everyday reality and physical reality.

Jana, how would you define reality? Well, there's many levels of reality. Like I can say this is my hand and that's real and true, but it's also made up of atoms and it's changing every second and it's losing some and absorbing some. So is it still my hand? I mean, we could get lost there forever. And so I think I've become more and more a follow the math kind of person. I want to know that there's some correlation between the structures in our minds

mathematically and some external experiences. And as Frank said, this can come on many levels and be probed from telescopes to accelerators. So they're all, you know, pieces in this complex mosaic that creates reality. Sarah? Oh, I was really hoping you weren't going to come to me. Yeah, I mean, I think it's my hand. I didn't think I'd ever doubt it was my hand. But then after, I think, as a non scientific person, reality to me is all kind of perception and while I'm aware that isn't pure purely real as in verifiable I go about my day and take thousands hundreds of things for granted including my own emotional responses as being correct and real and right so the only thing about reality that I do know is that when I dream, I definitely know that's not real. And isn't it crazy that we spend so much of our time in our brain asleep

and then we wake up and go, that's all completely fictional. I know that didn't happen, but the rest of it, this is definitely happening then. So do you find that you do sometimes, that you make that division in your head where you can say, this is my reality and this is a reality that is is a reality a common reality at all because that level of perception seems to be that is as you said one of the problematic things that once you realize there are these two things you know running in tandem i think getting bad reviews and

that kind of thing really helped me in comedy because someone else would say what's a terrible gig from an awful comedian i go well that's, that's your reality. In my reality, I was a genius and everyone loved it. Eric, you're not getting out of this one. Your definition of reality. Well, I think it's interesting for me because I do two things which impinge on that. One is being a writer and the other is being an actor. In both of those, we try and fake reality

to convince people that they're watching what reality is. And I think all writers create their own reality. I mean, Dickens' reality is different from D.H. Lawrence or T.E. Lawrence. But I think what we're trying to do is recreate reality. So we're actually second-generation people anyway. We don't really have any reality as actors and writers. want you to pick up on something that you all said and particularly i think frank you said that there are these two realities that you think of janna mentioned it as

well that there's the there's the obvious reality a three-dimensional reality that we experience as children and then there's a another level i part of the question is actually whether i should call it a deeper reality but as janna said, a mathematical reality that we discover through our observations. Just a bit of history. When does that distinction emerge in human thought? The idea that there is something deeper and specifically that that can be described by mathematics? Well, I don't know who thought of it first, but in our tradition and our Western tradition, certainly an early and striking version of this was Democritus, who said, in opinion, you have tastes and colours and hot and cold, but in reality, it's just atoms in the void. So that captured some of this idea

that there's a sort of working reality that we get around in. And then there's under the hood, there's something quite different going on. These different versions of reality don't conflict with each other. They, I mean, we, they, they're all describing the same world. And it's actually a great adventure to try to connect them up. That's why I said the hardest thing about reality for me to understand is how I'm part of it. When I look at the equations, the fundamental equations of physics and the concepts of quantum theory and so forth, it's very difficult to recognize myself in those equations. And it's really fun to try to connect these very profound beautiful sort of

sparse equations with the rich reality we actually experience. John that thing of what is reality I know that you started off as an undergraduate studying philosophy and you felt that it didn't tell you enough about reality and then you heard a lecture about quantum physics and suddenly you go, oh, finally something solid, a universe of probability, which to me is a really fascinating entrance to reality. Yeah, I think it was incredibly compelling for me to realize that there was a set of mathematical structures that did go beyond our perceptions and yet taught us predictable things that we could confirm with experiment and that was true in Bangladesh and it was true in a different galaxy and coming as a philosophy student where people were still trying to argue you know like what did Descartes mean and nobody's doing that with quantum physics or Einstein and we understand quantum physics

isn't complete but but with Einstein we know it's perfectly transferable to the next generation. Nobody's going, what did Einstein mean when he said equals mc squared? Once you learn it, it's exactly what Brian said in the end. In Minkowski space, it's a four vector that when you contract it, okay, whatever. So that was very powerful for me to walk away and have all of this kind of rhetoric get real quiet in the room. And everyone felt very deferential to the math and the science. And that impressed me tremendously. I think that's the point about it. I'm sorry, Brian.

Well, I was going to ask. I know that you read a great deal of science and science has always been part of your work. I mean, we go to the Galaxy Song, but it was those sketches, those Python sketches that dealt with science tended to be yours in the main. Do you see that? Do you feel that disconnect as Frank described it between the reality of your existence, just being a human being, and then this very strange world that we see, quantum mechanics and relativity and so on, that seems to underpin the reality that we perceive? Well, quite simply, no. But that is mainly because I don't understand quantum physics,

so I can't possibly comment on that. But I find the thing that I found interesting, why science appealed to me, was it replaced religion. And religion is an attempt to describe the universe from way back in the past, 2,000, 3,000 years ago, and science has now updated it. And that's all it is. It's not a difference of kind. It's a difference of degree, not really a difference of kind.

And so I'm always very kind to people who still have belief systems and think they're going to meet up with their relatives afterwards. I don't think there's a green room afterwards, but I'm happy for people to think that. I think whatever makes people happy is actually the only thing that really counts on this bleeding planet. Well, that's it. I was going to say, Tara, in both your books, you look particularly from a psychological and evolutionary perspective about human behaviour. It's not just good enough to say, well, that's what people do. You actually go to the roots of why we do certain things.

How much has that changed your attitude towards the reality of being human to go oh well actually this wasn't conscious and this was you know yeah it's very interesting you ask that because the difference between evolutionary evolutionary science and psychology and what these guys are talking about in terms of reality is that there's still a narrative attached of course there is evidence and there are studies where people are trying to find evidence but also there are studies where people are trying to find evidence, but also there are gaps where people suppose. And I think why that attracts me is I'm a words person. I don't understand the numbers, so I decided they don't matter. I can get around a Sainsbury's.

I've got all of the information that I need about reality, actually. And so, not that there's a competition between me and him. You'd better have someone count your change. Yeah. Well, that's the good thing now. You don't even need to take any money with me. Just a little plastic book. And you don't even have to count.

But, yeah, so, and I've realised that the parts of science that attract me are the ones that make sense to me, and it's because they're stories. They're always told. And evolution is a story about where we come from. And we can then go, oh, I reflect on myself and I see that that could be true of me. Or, oh, that makes sense in terms of how I've experienced human beings. And it's the exact opposite of this is a force that works.

And like you say, it works like that in Bangladesh and it will work like that in 200 years. But you can make stories out of it. Really? You really can, if you use your imagination. You don't necessarily have to master the equations in detail. If you're willing to trust people a little bit, you can make stories out of a great deal of it. And the stories can really enrich your experience of the world. It's interesting that underpinning this discussion already seems to be an implicit idea that the deepest description will be mathematical. I mean, you said that you don't necessarily need to understand the maths, that there can be stories told about it.

I wanted to explore that assumption, or indeed ask the question, is that an assumption? I don't think it is an assumption, because whatever we find will be necessary to understand things, we call it mathematics. The mathematical tools that we use in modern physics bear very little resemblance to the geometry of the Greeks or the methods that Newton used. They have a different character. They really have linear algebra and it's technically very different. And in some ways, they become simpler. When we get down to the most basic laws, they have a strange simplicity that we developed precise ways of thinking that we call mathematic to deal with this strange reality. But whatever it was, we would have called it mathematics, I think. Mathematics is just logical thinking carried to the extreme.

Yeah, I totally agree. Suppose telekinesis was possible and I could telekinetically move my cup. Presumably, I could do it every time in the same way. Otherwise, it would just you know, I don't think it's short-sightedness to say this is how we conceive of the world. We inherited these structures through evolution, logical systems that obey the laws of physics. And so the good fortune that it's encoded in the way we think is really not magic, right? Even the fact that we can invent math as a result of the way our neurons are configured, which is laid down by forces that led to evolution. So, I mean, and I do agree with Frank about the stories. We tell a very compelling story

about the origin of the universe and the evolution of the universe and the fate of the universe. And I could do something different with my time. I could count atoms in my room, but we don't think that's a good story. So as scientists, we don't fund those kinds of projects. And I'm sure it is a really good story.

But I don't know if you ever heard the ancient Egyptian one, but it was about a massive ejaculation. And it made the world. Is it as good as that? Frank? Is it as good as that? Frank? Well, it's a matter of taste, I guess, whatever turns you on.

One thing, to be a little bit serious, one thing that I want to share is my very strong feeling that you don't have to give up the stories you love in order to adopt the scientific stories as well. You can view the same thing in different ways. In fact, this is itself a principle of science called complementarity, that to answer different questions, to get insights about a situation or an object. Very different points of view may be appropriate and may be necessary and certainly could be a good thing. Well, Eric, I suppose this has been brought on by Frank and Sarah there,

the great debate of equation or ejaculation. And so in terms of 2021... I say equation and ejaculation. Well, let's pull the whole thing off anyway. I was going to say that's having your cake and eating it. That's been discredited in the UK. But, Eric, I do think it's an interesting point, isn't it, between that there is...

I think there is a point where you can find that the story of the beginning of the universe, when told mathematically, there is still, as Frank has said, there's a point where you can find that the story of the beginning of the universe when told mathematically there is still as frank has said that there's a point where the two can meet where the the level of art and the level of of science where objectivity and subjectivity you can something can still grow out of that that it does not merely create oh here's a set of numbers and and it was 480 quadrillion and they all lived happily ever after well that's true but i think we learn everything through stories. We teach each other, we tell each other everything through stories we always have,

since Homer, since... And we began to change our way we think about ourselves through the Elizabethan drama world and the 19th century novel. Now we look at ourselves through television. We see ourselves, people check themselves out in shop windows. We're aware of ourselves outside of ourselves, which has changed our nature of how we think about reality, I think. But I do actually like the idea that there is a science creation myth.

And I think that's coming along quite nicely. Because actually, science tells us that 96% of the universe is dark matter. So only 4% of the universe is visible, so 40 only four percent of the universe is visible so god is clearly hiding in the other 96 percent there's something i wanted to i wanted to get jana to disagree with einstein which is going to be okay in this sense though i got a sense from what you said we were talking about the fact that the universe is comprehensible and that mathematics is the label we give, I suppose, in a sense, to our comprehension. So whatever logical structure we choose, we'll call it mathematics.

I mean, Einstein famously said the fact that the universe is comprehensible is a miracle. But is it not the case that we have to live in a structured universe? You kind of referred to live in a structured universe? You kind of referred to it in a way, a universe of cause and effect. It's an anthropic effect. It's the fact that ordered structures like human brains must look out onto a universe that's ordered. Well, I think that's reverse direction because how do you get an ordered brain? So it's sort of a revert to presume that we just materialized in this world and then are surprised that we're projecting structures on the world.

It strikes me as the first mistake. So, I mean, again, evolution comes into how the structures are inherited in our brain and we haven't evolved presumably all the way that we can and we look at other animals that have some comprehension of an external reality, but not quite a meta level. So it isn't about human beings at all, I don't think. I think the entire paradigm of physics is basically the premise that we can predict the future from the past and the past from the future. And this includes quantum mechanics when we talk about things like the wave function of the universe. That wave function, that probability is deterministic. We predict its future from its past and its past from its future. And that's just the paradigm of

physics. If that turns out not to be the case, I mean, then we are in trouble when we try to pour hot coffee in the morning, right? Because the world is not the way we presume it is if there isn't that connection. And so the fact that we believe in physics is because that's our experience of this external reality, as filtered as it is by consciousness, as filtered as it is by the limitations of our senses. It is still, I'm still receiving photons from the early universe, you know, and they are hitting me and that's just happening. So maybe that was a loopy way of basically saying I think it's an observation, not a construction. And in terms of silence...

LAUGHTER But I agree with Einstein. I think it is a miracle that the universe is comprehensible at the level of depth and coherence of structure that fundamental science has achieved. You can do thought experiments and make universes in which that's not true. not true. For instance, specifically, we're getting to the point, I think soon, when we can construct worlds within computers and intelligences within computers that are not necessarily going to have the same relationships to what we call the external physical world that we do. Their sensoria will not be photons coming out of the external universe, but electrical signals within the computers. And the programmers could make any old programs that they want, any old

rules that could be as horribly complicated as Word or DOS. If you're old enough to remember these nightmarish operating systems that are not terribly coherent, not terribly coherent, and kind of constructed not with a view of elegance, but the fundamental understanding of the universe as we actually find it, what we call physical reality, turns out to be remarkably beautiful and comprehensible. And its detailed study really rewards the effort. Can I also recommend to Sarah and Eric that all three of us should more often start sentences with, I agree with Einstein. I think it would impress a lot of people. But I think it's best

we stop there, whereas Frank can then continue after that. I think if we just say, I agree with Einstein, and then move on to another vol-au-vent. I agree with Einstein. Just to follow up, it might be slightly off topic. I just wanted to follow up on that, Frank. So if you make the argument that there can be, that the universe could have been different,

that the universe could have been different. How do you reconcile that with the quest? You may not think this is a sensible quest, but a quest for a theory of everything in the sense that there's only one logically consistent way the universe can be, and we may have access to that. No, I think it's a great question, which I ask myself all the time. In recent years, I think it's a great question, which I ask myself all the time. In recent years, I've kind of backed away from studying the universe as a whole and studying the universes,

sub-universes that are realized in physical bodies. So a solid, a substance can be thought of as a universe on its own. And different possibilities arise when you consider materials as worlds in their own. For instance, you, well, to get a little bit technical, for a long time, people thought that all particles had to be of two types. There were two kingdoms called fermions and bosons. By fantasizing about alternative universes in two dimensions, by fantasizing about alternative universes in two dimensions, I realized there was another possibility, anyons, and it was a great joy a few months ago when people finally actually observed it. So thinking about how the world could be different

is sort of what I do for a living. I try to get different descriptions, different possibilities, improve the equations, not be satisfied with the equations or the platforms we have. What was your question again? It was whether physics, some physicists... Oh, whether there's a theory of everything. Well, I hate that phrase. I really do. I think it's horrible because it promises much more than physics can ever deliver. Physics will never be able to answer questions about what you should do, what's morally correct. So that's one aspect.

And the other aspect is that much more down to earth, even if you have the fundamental equations, that leaves you with the task of finding yourself or more down to earth, finding animals and finding the description of more complex objects using intermediate concepts. Knowing that a person is made out of quarks and gluons and photons and electrons doesn't really help you very much in understanding that person. So a so-called theory of everything would not be a theory of much of anything really. Sarah, Frank's previous book, A Beautiful Question, which looked at the beauty of science. Do you find that as we find out more about an

underlying reality, something which is not necessarily something that we can observe on a day-to-day basis, do you find that that makes reality more beautiful? I agree with Einstein that reality is very, very good looking, very beautiful. And I think on a human level, to be just one lady alive now, since I was a child, any talk about science made me feel so lucky to be alive there's something about talking about whether it's consciousness or gravity or you know black holes and planets every single thing the I guess for me and and probably not to scientists but everything seems so miraculous that it all comes back to isn't it amazing not only that it's happening but that I got here to see it like and that's why I think I was drawn to biology was

that the the chances of any of us existing in terms of I'm not going to say the e-word again but all of the potential in our fathers. All of it. Yeah, everything's always made me feel very lucky to be alive and that's where the beauty comes from on a personal level is it actually reminds you I'm here and I'm glad to be learning about it. That's great, by the way. The way you said that is very much

if a physicist had written The Joy of Sex. At this point, the man has a great deal of potentiality. I'm sadly the man no longer has potentiality. Yeah, it's not E equals MC squared, it's E equals... Eric, how do you... Again, as someone who's become so much more intrigued about understanding reality at a more fundamental level, do you find that's changed your... Certainly, to me me it feels it removes the mundanity of almost everything that once you

start engaging with its complexity nothing is mundane um well i i think the basic thing is that because we're human that the thing that makes us human is we die and that the death is the most important about science because you have to get it in the small space of time so what sarah's saying about the wonderful thing about being alive in these bodies in this time is you can see all this going on we can actually have a nobel scientist trying to explain to us about reality this is extraordinary time and then extraordinary you know to be here so um i i forget question too, but I agree with Einstein. There is a book, you know, called The Joy of X, written by a mathematician.

Is it about divorce? It's about the variable X. I thought you were going to say it was John Cleese's latest book. The problem that we have as human beings to some extent, which is, as you said, the mathematics. Once you have the mathematics, and we've heard this before, that beautiful thing, which is if the maths works, it means it exists, even though we haven't found it yet. That's a question that's hard to answer. I mean, we know irrational numbers exist, numbers that have an infinite list of unpredictable digits. But we've never seen one in reality because eventually your measurement ends at some finite list of unpredictable digits, but we've never seen one in reality, because eventually your measurement ends at some finite list of digits. So it's, you know, a curious thing,

like, does every mathematical concept exist? And we could say, oh, I can imagine irrational numbers actually exist, and it's a limitation of our experimental apparatus. But it's not, I mean, does, and I love playing devil's advocate on this. Sometimes, I believe every conceivable mathematical structure will find a manifestation in reality. Maybe that'll just happen. And black holes are an example of that, something that we thought nature would forbid, but math allowed. And then nature figures out a way to make some. Oh, my God, that sounds like an amazing film. Doesn't it? Like a sub,... Those two forces against each other.

Nature said no, but maths said watch this. The opening will be you going to Sainsbury's and going, oh, no, the aisle numbers are irrational. I'll never be able to find the things now. This is worse than when waitrose had those aisles using imaginary numbers. This is worse than when waitrose had those aisles using imaginary numbers. This is very problematic. When we talk about the universe, we have to think about what we mean. I mean, each of us is a universe in a way.

We experience things in different ways. Our Earth is a universe in a way. And if we ask, did the Earth have to have the precise properties that it does? Could it have been a little further from the sun or a little closer? We find that now when we study the distant objects, that many stars have planetary systems with all kinds of different properties. So for most purposes, those are universes. We have to work very hard to get signals from other places that are very far away.

And they can be quite different. So yes, at that level, you can certainly have a multiverse. If things had been slightly different, the dinosaurs might still be around and this discussion would be quite different. So yes, I like the idea of a multiverse. What the debate in fundamental physics now is whether there are really, really, really distant parts of the universe, very, very, very, very difficult to observe that have even laws that appear to be quite fundamental different. Like they could, for instance, in those parts of the universe, instead of having three dimensions of space, you could have four or two or six or something else. And that's entirely possible and is very much in line with my attitude, which is that every material defines a universe and materials can have sub-materials. You can have layers within computers that define two-dimensional worlds. So I love the idea of not just one universe, but many universes. And I think to do justice to reality, you have to have that idea.

Eric, I was just wondering, again, in terms of these, as you discover more, as Frank was briefly talking about ideas of multiverse, et cetera, as a writer, your work is what-ifs. And have you found that in terms of finding out this level of reality and the fact that the what-ifs increase, does that actually become an inspiration in terms of where you can take the worlds that you're creating? Well, I don't think so, with respect.

I think because we write about people and we write about their emotions and going shopping at Sainsbury's. I think we're more in the day-to-day. We're not really looking at this fundamental, what makes their bodies energise their bodies to go and buy more food to eat so they can carry on

shopping. We don't really deal with that. We tend to deal with what we call emotions, which are nasty, unpleasant, sticky things which shouldn't be mentioned in society, really. Well, that's always what Brian says. Once the universe moved to a point of chemistry, everything started to go downhill. When Eric does write about specifics,

I'm thinking now of the Galaxy song, then I correct him. I'm always looking over his shoulder now. You've been correcting me for so long that they've changed again, so I'm afraid you have to start correcting you. And if you want to know how Eric feels about this correction, you might have seen the O2 show, in which Eric wrote a piece where Stephen Hawking eventually runs over.

In fact, lands on top of you, I think. Stephen Hawking in his wheelchair runs over Brian Fox and I wrote that joke and Brian filmed it. Bless him. But it was dealing with a lot of Freudian issues.

But Stephen did, of course, if you remember, Eric, ad lib the line that's in the Python show, because when I explained that the galaxy song is wrong and the universe is not, I don't know what your age of the universe was when you wrote it, 12 billion years, and now it's 13.8 billion because of new measurements.

And he said, I think you're being pedantic. Accuracy. So he's a theoretical cosmologist. Luckily, we were rolling sound, so we actually have Stephen Hawking. Way too pedantic. We cut that out and put it in the show. So it's actually...

As Brian gets run over by Stephen Hawking, he says, way too pedantic at it. Well, that's Frank. Frank's got a Nobel Prize. It is demanding accuracy. Is it pedantic? I don't think that's pedantic. Well, it can be. It depends what you're after. Well, this is annoying.

We're nearly at the end, and we've got to question three of 18, which is good, so I think we've got a lot of work to do. But what we haven't really dealt with, when we're talking about sometimes what you might consider to be the shortcomings of our senses, and then we have, especially we see in the 20th century and into the 21st century, the ability to build machines, find technology that allows us to become aware of a fundamental reality. It's a wonderful thing that as we learn that there's much more of the universe that we don't naturally experience, we can also devise tools to expand our minds. William Blake said that if

the doors of perception were cleansed, a man would see the world as it is infinite and i think we're living that and it's a very exciting time to be alive sarah i wanted to ask you about those moments every now and again where you go um this bit of reality is really hard to accept and really when you start to what for you have been the most difficult ideas when you've and and then that kind of satisfaction when you go okay i can i can accept that do you know what there's something that links a lot of the when you've been talking all of you about physics um it's actually reminding me of chemistry at school and And when we were told that

the people who were discovering elements, they knew from what they discovered that there were other ones. And we were shown these gaps. And they said, we know we will find them one day. And that's actually quite a huge thing to tell a teenager who's maybe not listening properly. Because what you're saying is is here's some evidence, evidence that you will never see in Romford. You'll never see it at Sainsbury's or the ice skating rink, but just trust us.

And again, it's fundamental, isn't it? The elements, the smallest things, nothing smaller. And because we found him, him and her, we'll also one day meet these ones in the corner. And actually, I think it's something that's affecting society in general at the moment in terms of trusting scientists, is that it's about replication and understanding certain rules.

And you do have to sometimes trust, just because it doesn't make sense to me yet, I really have to listen to the people who say this is how the world works. Yeah, and sometimes we predict things in advance that are quite surprising and turn out to be true. And of course, the products of our understanding are the technology that allows us to have a show like this and talk with each other at great distances and see the images. It is all based on quantum mechanics and using it to understand matter and make it do wonderful tricks wonderful tricks is great that just say what is the universe it is a wonderful trick and inside that trigger because it's such a beautiful thing um we also always ask the audience a question as well just just in case we feel that the uh our panel haven't entirely

fulfilled the remit we uh we always throw out a question to our audience. And today we asked them, if you could change one thing about the physical reality of the universe, what would it be and why? What have you got, Brian? They're quite surreal. So Joe Butler says, any time a neutrino interacts with another particle,

comma, so that's very sensible, that turns the object into raspberry jelly. that turns the object into raspberry jelly. That's what Joe would change about the laws of nature. Will Goring says, Plank's constant, so we can actually measure the time between government U-turns on Covid policy. Eleanor Turner is more, just less ambitious than the raspberry jelly or the Planet's Constant.

She says, honestly, I just want more crisps in a crisp packet. We are definitely discovering that our audience is hungry today, aren't they? They are very hungry. We have a few more. Shona says, I'd like to close the wormhole that steals all my socks, please. Here's the last one. This is my favourite one. I haven't read it all, so I don't know where it's going. It's quite long.

But it says, Schrodinger left that poor cat outside the box to have a bowl of milk and to live a long and happy life. Now it's stuck inside there forever, undead but dead. We would have a nicer university if the cat was free. Free the cat. That's what I say. Free the cat. Thank you very I say. Free the cat.

Thank you very much to all our online audience for those answers. And thank you very much to our fantastic panel today. Frank Wilczek, Jan Eleven, Sarah Pascoe and Eric Idle. Next week, which will be the final episode of this series, I believe, we are going to do the history of rock, which, of course, was Brian's request that we do the history of rock. But unlike Lazy Lazy BBC 4, we're not just going to go back to Tommy Steele and Skiffle.

We're going back 4.28 billion years to the faux amphibolites. That's right. We're going to deal the faux amphibolites. That's right, we're going to deal with faux amphibolites. And if you have ever been looking for a band name from a 1994 John Peel session, faux amphibolites is undoubtedly. I think that was a lot better than Sandy Sediment, actually, who I think just seemed to kind of drift away over the years. So there we are. So, History of Rock next week.

Thank you. I hope you now can accept or reject reality with greater ease. Goodbye. Thank you. Turned now nice again Hi, I'm Zand van Tulleken And I'm Kimberly Wilson And just before you go, we wanted to quickly tell you about our podcast

Made of stronger stuff from BBC Radio 4 I'm a psychologist and Zand is a medical doctor And we're bringing together our specialties to take a tour of the human body Each week we hone in on a specific body part From the eyes and lungs to the appendix and we're bringing together our specialties to take a tour of the human body. Each week we hone in on a specific body part, from the eyes and lungs to the appendix or the vagus nerve, and we ask how we can understand it better, ourselves more, and combine the body and mind to produce positive change. So subscribe to Made of Stronger Stuff on BBC Sounds. This is the first radio ad you can smell.

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