Science & Technology Q&A for Kids (and others) [Part 130]

Hi, everyone. Welcome to another Q and A about science and technology for kids and others. I thought I'm trying to change up a little bit the way that I'm doing these things. On Fridays. I'm now alternating between general Q and A about science and technology for kids and others. And Q and A about future of science and technology on alternate weeks. This week is a general Q and A. I also thought this week maybe I would encourage people to ask questions that sort of seem simple, but which maybe they're not sure they know the answers to. And I'll try and try and address them. I see an interesting one here from Parker that says, is it possible to create more universe? That's an interesting and kind of complicated question. So actually relates a lot to work that I've done on fundamental theories of physics. And, well, let's start off with some basics. So normally, kind of the background for what's happening in the universe is that there's space. There's something where you can put things here or there sort of in the universe. And the traditional view that up until about 100 and something years ago, people sort of imagined that space was just this completely background thing that had no character of its own. It was just, you put things here, you put things there. And it was just something where you could do geometry in space. And space was just this pure static background. Then with Einstein's general theory of relativity that came out in 1915, there was kind of the idea that it was that one should think about space as having some potential structure, for example, being curved, for example, that a massive object could curve space. And that that was a way of accounting for the presence of gravity. And so that was sort of a place where it started to look like there was something about space that wasn't just this pure background static thing. It was something where there was some level of kind of kind of character to space where it wasn't like every piece of space everywhere in the universe is the same. There could be a piece of space that was curved as a result of the presence of mass. And that curvature would lead to the force of gravity and so on. And roughly why that happens is normally if you say. And this is something that was kind of thought about from the time of Newton in the late 1600s, this Newton's first law, that if you just start something going and in some direction, and you don't operate on it with any force, you just let it go, then it will go in a straight line. And that was, by the way, at the time in Newton's time that was not a trivial hypothesis to make because in Newton's time one didn't have. It was if you push something on the ground, it was just going to come to a halt because there was going to be friction and so on. You didn't have nice air hockey tables that people use to demonstrate this stuff now with very low frequency friction and so on. I mean, I suspect actually in Newton's time, I think it was a time soon after at least the little Ice age. So I think even kind of where Newton lived, probably the rivers were frozen much of the time. So maybe he did have the analog of the air hockey table. Maybe he could, I actually don't know. Maybe he could have sort of slid things around on these frozen rivers and known that there was had a notion of a lack of kind of frictional force, which is a good, good history history footnote thing to look up since the. I know the Central England temperature measurement, I think was started in 1650. So it must have covered the time. It's the longest running kind of measurement of, of temperatures on the Earth that exists. And so that must cover the time of Newton. So anyway, something to look up. But in any case, back to this. So in Newton's idea of how mechanics worked, things that weren't acted on by a force would just go in straight lines. And for example, light, you shine a laser somewhere, it just kind of goes in a straight line. But more precisely, you can think of it as going from where it starts to where it ends by the shortest path. And in normal geometry, you take a piece of string, you pull on the ends, the string will go straight. The shortest path between two points is a straight line. However, if you are on a curved space. So for example, instead of the string just being out in the air, so to speak, it's on the surface of a sphere. Let's say the string doesn't get to go in a purely straight line because it's following the surface of the sphere, but it gets to go on a great circle in the case of the sphere gets to go on a path that happens to be curved there. If you imagine that the thing is on kind of a table that has a depression in the middle, then these shortest paths will end up being deformed by the presence of that depression. And then. So that's kind of Einstein's idea of how things work in physical space is that the space is curved as a result of the presence of mass. And the presence of that curvature means that the shortest paths between two points are no longer straight lines, they're instead deflected lines that are deflected. And that deflection turns out to correspond to the deflection associated with gravity. So that was kind of the idea of Einstein's idea. So one of the things that came up in the equations that Einstein derived for the relationship between curvature and mass and so on was the prediction that the universe should expand and that the, that the sort of, in some sense the total amount of space, the total distance by amount of space, we can say how long does it take to go from here to there? That the time it would take to go all the way across the universe or to go a quarter of the way across the universe or something would be longer later on than it was earlier in the history of the universe. So in other words, that's the sense in which the universe would be expanding. So Einstein sort of saw that that was what the equations implied, said that couldn't possibly be right. We know the universe isn't expanding. He said, look, it's not expanding. It kind of reminds one of the pre Copernicus kind of view of, look, we know the Earth isn't moving around the sun. We know the Earth is stationary because we're here standing on it, so to speak. But Einstein made the same mistake. He always characterized it as his biggest science mistake. And so he added a term to his equations, the so called cosmological term, which would sort of, with which would kind of go against this, this force of expansion that was otherwise predicted. Okay, well, it turns out it was a mistake. And a chap called Edwin Hubble about, oh, less than 10 years later observed the expansion of the universe. So in other words, what that means is that in some sense the space is expanding. There is, you could say in Einstein's view of things, there is more space because it takes longer to go some percentage of the way across the universe later in the history of the universe than earlier in the history of the universe. Now it can get kind of complicated because in the, you know, if you're one second after the beginning of the universe and you say, well, gosh, you can get all the way across the universe and, and it's going to take you three seconds. Well, you didn't have three seconds to get all the way across the universe in the 1 second since the universe started, so to speak. So the expansion of the universe in some sense is not chasable. It's a general feature of it. Depending on its details, it can end up sort of not being traceable by anything that was Sort of trying to get to the edge of the universe. By the time you get there, it's expanded, okay? So in the usual sort of view of how space works, in the traditional view, and I would say the classic view, the classical view of how space works, it is this idea that the universe expands. The distance between things gets larger, and in some sense, space is expanding. So you could say there's more universe there. There's more sort of distance in space available, okay? But in that picture of things, there is a description of things like curvature in space. But space isn't really a thing. Space is just this sort of background that has certain characteristics, but it's not sort of in and of itself a thing. Now, it can have. Can have very violent characteristics, like it can form event horizons around black holes. It can be. It can be sort of. It can be very distorted, but it's still just a background. Now, in our model of physics, space really does become a thing. Space is no longer just a background that you put things in. Space is an actual structure of its own. It's some kind of graph where there are just points, kind of atoms of space. And there are connections between those atoms of space that form a giant network. And there is nothing in the universe other than that network. There's no background. It's not like the network is put into something. All you know about the universe is there's this network, and it's atoms of space that are related to each other, that are effectively connected to each other. Okay? So in that picture, the universe consists of some number of atoms of space. Maybe it's, you know, a one with 400 zeros after it, 10 to the 400 atoms of space that make up our universe. And in that case, there's kind of. That's the universe and everything in it. So that big network has to represent both the thing we call space and all the things like particles, like electrons and photons and all those kinds of things that exist in space. And the picture is that there's this network, and it's kind of always bubbling around. It's always rewriting itself. It's always updating itself. It has a certain. A certain. There's all this activity in it. And the fact that there's activity is the reason that one part of space can sort of communicate with another part. Because there's activity here, and that's connected to activity. That activity sort of entrains activity a little bit over, and that entrains activity further over and so on. And then if you let the activity Run for a little while, a certain amount of time. Then you will. The thing that is over here will eventually be able to affect the thing that's over here. And that's kind of what knits together some coherent structure of space. If it wasn't for that activity, there'd be just all these separate atoms of space. They would have no relationship to each other. They would have no communication between each other. There wouldn't be this thing that we can think of as this kind of background of space. And when it comes in our models to things like particles, we imagine that those are certain sort of robust features of this network that represents the structure of space. Much like an analogy I tend to use. In a fluid like water, we know there's a bunch of molecules bouncing around underneath. But we think of it as this sort of continuous fluid. But we can have features like a little eddy in the water which is made of molecules. But which molecules it's made of can change over time. But that eddy has some kind of character, some kind of continued persistence that is independent of the details of the molecules which it's made of. It's just its overall structure has a certain persistence. And that's how we think particles like electrons and so on work in the universe, in the actual space that exists in the universe. So in some sense, in our model, the only thing in the universe is space. But space has features that lead to the kinds of things we know about, like all these particles and so on. The particles and all these features of space that we know and care about are a tiny little piece of froth on top of the main activity of the universe, which is just the continual rewriting of pieces of space. The sort of knitting together of pieces of space. So in our model, the expansion of the universe can actually be a growth in this network. You could start off with a very small number of atoms of space, maybe just one. And over time, this network is rewritten. And what was three atoms of space will turn into something with five atoms of space. Let's say it's all just. You can kind of see it as just rewriting of this network. And so in our model, there actually can be more space in the universe. There can be. Unlike in general relativity, in standard sort of classical physics, so to speak, you can. I don't really know what to call our kind of physics. Because in the sort of nomenclature of physics, there's classical physics, which was before the 1920s, and that did not deal with quantum mechanics and so on. And then there's what is usually called Modern physics, which is 1920s on. I suppose when I was learning about that stuff in the 1960s, it was still somewhat modern, but now we're another 50 years later. And I think it's kind of funny that it's still called modern. It reminds me of these places where, oh, like when I was in Oxford, there are these different colleges that are part of the university in Oxford. And one of those colleges is called New College. And you might guess New College is actually the second oldest college, dating from sometime in the 1300s or something. It was called New College to distinguish it from the original college. But of course now it's not new because it dates from the 1300s. So modern physics is actually 100 years old. And now we have a very different view of how the foundations of physics work. That's come out of our physics project. And I guess it needs a new name. So if people have suggestions for that name, they should make it, because it's got to make it into the textbooks at some point. And you can't have a section or a class on modern physics. It has to be. I don't. Postmodern is not the right word because that has too many other connotations. And also that's kind of not building for the future because that's just a moment in time type designation. But any case, in our view of physics, the space consists of this kind of discrete collection of atoms of space. And there can be more of it over time. And in fact, the expectation is that the expansion of the universe is associated with the actual making of more atoms of space in the universe. Now, it gets a lot trickier than that when you really start drilling down and asking about what time is, because I'm talking about how the universe, the network, is getting rewritten, but different parts of the network, they will have the possibility of being rewritten. But you say, are they actually rewritten? Well, you can have this kind of. This notion of different kind of reference frames where the different parts of the universe are kind of rewritten in different orders and all kinds of different things like this. So it gets a little bit more complicated. But the basic idea is you can think of it as being okay at this moment, at the beginning of the universe, there were only two atoms of space or something. Now there are ten to the 400 atoms of space. There are progressively more atoms of space. There's kind of more universe there. Now weird things can happen in our models. Like pieces of the universe can break off, and that can happen well inside. If you have a black Hole that's spinning too rapidly. You'll actually have a part of the universe that breaks off as a separate disconnected piece of the network. So you can both make more space and you can actually decrease the number of atoms of space as well through the actual rewrite of the network. You can also have pieces that break off that are like, you know, marooned pieces of the universe, so to speak. So in our model of physics, yes, it is possible to make more universe. You can make more atoms of space. And it's. But that's something that is, as I would say, a little bit different in character from the way one would normally think about things. In standard classical general relativity, classical sort of theory of gravity, you really don't talk about more space. You just talk about a parameter that is the radius of the universe basically that can increase, which is a little different than saying there's more space there. Now you can kind of, I suppose when you start thinking, even in classical, classical quantum whatever physics, you can. Maybe we should talk about our physics as being rule physics because it relates to pieces of the ruliad, which is this kind of entangled limit of all possible computations, so to speak, of which we get to sort of observe just one slice. In any case, the thing that, let's see, I was going to say is in. Gosh, that was a mistake for me to have a digression there because I think I lost my train of thought. The. Yeah, we're talking about kind of. Can there be more? Yes, yes. So. So in traditional physics, the vacuum, the supposed emptiness of space is not actually a vacuum, is not actually empty. According to quantum mechanics, there are all these always these quantum fluctuations. And in fact, every particle, electrons, photons, whatever else, virtual versions of that particle, together with sandiparticle continually come into existence and go out of existence all the time. And there's this kind of zero point fluctuations, quantum fluctuations that exist even the vacuum. So space in quantum mechanics is constantly bubbling with these different particles coming into existence, going out of existence. We don't get to make direct observations of those things, though there are some experiments you can do which, which show the existence of those kinds of effects. Now, in our models, our kind of knitting together of the structure of space by the rewriting of this GRA network is kind of a very low level version of those particle antiparticle vacuum fluctuations. Vacuum fluctuations are a kind of sign of that same sort of activity through the knitting together of the structure of space that one has in the. That we have this kind of knitting together with structure of space and sort of high above that, you can kind of see the effects of that in these virtual particles that come into existence, go out of existence. It's always been kind of a mystery that when these virtual particles exist and they keep on bubbling around, they have a large effective mass. They have such a large effective mass that if that particle mass existed in the universe, it would curl the universe up into a little tiny ball and there wouldn't be much universe. It wouldn't be able to expand in the way that the universe has expanded. And in our models, that doesn't happen because in a sense, all that energy, all that mass that's associated with, in the end, virtual particles is the same activity that is creating space in the first place. And so that means that it doesn't have that same gravitational effect. In the usual theory. There's gravity on the one hand, which is being affected by all of these virtual particles. And the virtual particles, they're sort of a separate thing from gravity. It's like on top of the gravity is sort of on top of that. Whereas in our models these are all integrated together and so there's no longer that sort of paradox. So. Good question though. All right, let's see. Rock asks. Well, actually, I've got one. There's one here from Aaron. Why does running my water pick interrupt Bluetooth connections? So showing minor cultural knowledge, a water pick is this thing that squirts high pressure water to clean out one's teeth. It actually is rather, rather a nice device. And so I assume it has an electric motor in it. And the. Okay, so Bluetooth connections are the radio connections between devices. They're sort of very commonly used whether it's between AirPods and a phone or whether it's between, or any air, almost anything, tags, pods, whatever. Um, it's, it's a kind of a, a, a short range maybe. Oh, depending whether there's obstructions in the way. Maybe 20ft, 50ft, kind of range of, of communication, of radio communication. And devices have this. They're actually different kinds of Bluetooth. There's Bluetooth and there's Bluetooth low energy. But that they're similar for these purposes. And what's happening is your phone, for example, if you switch on Bluetooth, it's sending these radio signals back and forth to whatever device you're communicating with. And they are. Oh gosh, they must be radio signals where the, the wavelength is. Oh, I would say, I think, let's see, I have to work it out. 8. I think it's a Few centimeters. I think that's right wavelength. And it's. Bluetooth is not sending very much data and it's doing it in a way that is very much able to have errors that come from the radio wave hitting some metal pole and not being distorted and all this kind of thing. Those kinds of errors. It is full of error correcting codes that try to correct individual pieces of the radio signal not having arrived. So Bluetooth tends to be within, within its range. It tends to be fairly resilient to weird things happening because it, I, I believe it is a protocol that resends. I believe it goes both ways. I believe it has a handshake where the device that's receiving it tells the device that's sending oh yes, I got that packet or no, I didn't get that packet. That's the difference on the web between tcp, the usual protocol used for web browsers and udp, the protocol that's used for streaming where it's just like send the data out. Don't worry, don't tell the server whether you got it or not. If you as the receiver found you didn't get what you wanted, you can always request it, but you don't explicitly tell, tell the server whether you got it. So I think I'm a little surprised. Okay, so what would interrupt kind of that radio signal? Well, something else that's making radio signals and there are things like for example, if you have a spark, an electrically generated spark, a piece of sort of micro lightning that's producing radio energy at all radio frequencies and, or pretty much all radio frequencies. And so if you're, if you have something which is supposed to be receiving some radio signal and there's this, you know, there's this sort of micro lightning strike, then it's going to get a burst of incorrect kind of from the micro lightning strike rather than from the original transmitter piece of radio energy. And so it's going to get confused. It's not going to know what's going on. I'm surprised that a Bluetooth system would get confused because I thought it had good enough error correction retransmission that that wouldn't happen. But maybe if you have a device that is continually having some little short where it's got a little, I have to believe that would run the batteries down really quickly. But maybe if it's plugged into the wall, it could have some short that is producing enough radio energy that it's able to kind of interrupt the confuse the Bluetooth communication. Let's see, question that Was my attempt at that, at least, without knowing more. All right. Rock asks. Says in third grade, I had an argument with a teacher. She said, before humans had language, they thought just like us. I argue that couldn't be true. Instead, language gave way to complex thoughts. Was I right? Well, interesting question. I mean, there's been a long tradition in philosophy, kind of linguistic tradition of philosophy, that kind of a lot of that kind of conflates thoughts with language, so to speak. The question is, well, first of all, what is language and how does it relate to thoughts in our brains? We've got 100 billion-ish neurons. They're firing all the time, a thousand times a second, in many cases. Lots of electrical signals going on in our brains, lots of stuff happening in our brains. But somehow we communicate things that are happening in our brains to other humans. And how do we do that? Well, you know, if you could take some kind of version, if you could get all the electrical signals from my brain and you could kind of play that into your brain, it probably wouldn't be terribly useful, because your brain is set up in a different way than my brain. Everybody's brain is set up in a different way. The details of where the neurons are, exactly which neuron fires when this is going on, that's all different. So you can't really just take kind of an engram of one brain and sort of plug it into another brain. Instead, you have to have some way of taking the thoughts in one brain and packaging them up in some robust way so that they can be communicated to another brain. And I think that's sort of in the end, that's kind of what language is doing for us. It's taking this incoherent collection of kind of nerve firings in my brain and allowing me to form a word like brain or something. And that word represents a concept which is some whole giant collection of neuron firings in my brain. That word is then something that I can robustly communicate to another brain. That other brain can unpack the word and turn it into that whole collection of nerve firings that they have themselves. And so, in a sense, that's sort of what language is doing, is encapsulating. It's kind of. It's making a sort of package from thoughts going on in my brain, packaging it up so that it is sort of compatible with transmission to another brain. So this question of whether there is sort of stuff going on in my brain even without having formed it into that packaging, is an interesting question. There undoubtedly is. I mean, even in the lowest sort of animals which have brains, we can see there's brain activity, there's thoughts going on in some sense. Now maybe you don't want to call them thoughts because a thought, not expressible, a thought that's mere nerve firings. Is it a thought? So for example, let's say there are parts of my brain that, you know, there's a part of my brain that's important for keeping my heart beating. There's a part of my brain that's important for regulating temperature. The part of my brain that has to do with dealing with certain sort of reflexes and so on. Some of that is carried out not in the brain but to just in nerve trunks in the spinal cord and things like that. So there's parts of my brain where there are nerve firings and there's things happening, heartbeats are going on, things like this. Are those nerve firings things in my brain that we should call thoughts? Perhaps not. Perhaps the part of our brains that keeps our heart beating is. It's, it's brain activity, but it's not thought. And that's, you know, in, in there's sort of a, a concept and for sort of lower animals and things there are things that happen that keep their hearts beating and things like that which you might not say are thoughts. So this question of whether it raises to the level of being a thought, you might argue that it's not a convincing thought until you can package it up in this kind of linguistic lump that can be communicated to another human. I think the question of whether our brains, whether we can sort of in our brains, to what extent are we doing things that represent sort of a whole tower of kind of thinking? And to what extent are we just like we see the banana, we pick the banana type thing, to what extent are we just doing that sort of short term loop of kind of like the reflexes that we have, if you hit your leg just below your knee, your lower leg will kick out. That's a reflex. That is something that is just associated with low level operation of the nervous system and that you could sort of generalize that a bit. That, you know, the animal does this or that just based on its low level reflexes. And you could say, well, that's not real thinking. To get real thinking, you need to be able to sit there and ponder and go from one thought to another to another and to sort of stack the thoughts up to get to something which is kind of a more, a more derived kind of thing. And that's related to things like planning. Can you decide, you know, if you see the banana and you can reach out and pick it, that's one thing. But if you get this stick and you hit piece of the tree and then you do this and then you do that, and you're kind of using tools and you're doing this whole plan that, that involves kind of a stack of thoughts to get to the thing you want to get to, then that's a more convincing kind of thinking process. So now the question is, what does it take to have a stack of thoughts? What does it take to be able to stack one sort of concept or one thing on top of another? Maybe it takes within one's own brain some kind of way in which one has a kind of mind's language that is a packaging within one's own brain of the same kind that we have of packaging from one brain to another. Maybe in order to build those towers of thoughts, we have to be able to kind of encapsulate all those neuron firings into oh, yeah, that's a concept, it's a robust thing. We can take that. We can now sort of take a modular version of that and then build the next thing on top of it. Maybe we need to have that kind of thing in order to have serious internal sort of sustained thinking. I don't think anybody knows. In fact, I was just doing some experiments myself on artificial neural networks. And it's a little bit harder to see in the case of large language models where they're producing language. If you say, well, what happens if you break a piece of the network? If you just say, I'll zero out that part of the network, what happens? Well, it'll start getting. Saying words wrong. It'll start making mistakes of various kinds. And eventually it'll just. It'll start, you know, speaking total nonsense and then it'll maybe just fall silent. You can do the same thing with image generation. And there you can kind of knock out pieces of the artificial brain that's generating the image. And you start seeing these weird different images being produced. It's kind of looking at something where you start off from this. This brain that's aligned and sort of works. Well, maybe not quite the same way human brains work, but it's aligned with, with kind of human thinking in the sense that it knows kind of the types of images that we are used to seeing. And then you say, well, let's perturb that. Let's make an alien mind that's a bit different from that. What does it see in Its mind's eye, so to speak. When it's sort of synthesizing these images, you could do the same thing. What does it see in its sort of mind's language? If it's synthesizing language and you can see it kind of diverge from human language. But so I think that's kind of a way of perhaps thinking about this question of is there thought without language? It's not transmittable brain to brain without language or something like language. It might not be buildable up in many steps, even within one brain without that. But we don't know that yet. I think it's an interesting question. I mean, in fact, with large language models like ChatGPT and so on, one of the weird things is that the inner thoughts, when it generates one new word, it's just sort of rippling through the neural net with all kinds of complicated stuff with all kinds of numbers being added and multiplied and all this kind of thing. And then it produces a word. And then when it's going to produce the next word, it has this sort of outer loop where it's looking at all the words it's made so far and then deciding how to produce the next word. And that kind of outer loop is, I think, the. That. That's kind of analogous to. It had to have language to have that outer loop. It had to be looking at these words it produced. It's not good enough for it to be looking at, at least in the way that we architect neural nets right now. It's not good enough for it to be taking the inner thought, so to speak. It needs to have this outer loop where it could definitively produce a piece of language which it can then look at and then build for the next thing. So I think that that's kind of, at least in the current architecture of something like that, that kind of argues for the idea that you sort of need language to build a tower of thoughts. It's kind of a chain of thought reasoning is what people are calling it in the case of large language models. And, you know, it's possible that the way brains are architected, that's something you fundamentally need. And that's kind of an argument why you're. Well, that you might have been right, that, you know, language is what made possible complex thoughts by being able to sort of build these towers in brains where that wouldn't have been possible if you'd been. If you hadn't had sort of modularized these things into concepts. A few thoughts there. Let's see. Robot asks, why do Many medications have side effects. Interesting. Well, so, you know, you make up some chemical, some drug, you create it. People figure out, oh, we want this molecule that has a certain shape that's going to fit into this other molecule that's going to cause us to, I don't know, have, you know, be better with respect to some disease or whatever else. So you're, you're kind of. You have a particular target in mind. You have a particular thing. We say, I want this drug, this medication, to do this particular thing. Okay, great. Well, the problem is that there are many different ways in which that molecule, for example, can do things other than the thing you intended it to do. So, for example, a very simple case would be there's a molecule and it's supposed to fit into a hole, another molecule, to gum up that hole, to prevent something else happening from that hole in that molecule. And a lot of the way we operate at the level of molecular biology has to do with what molecule fits into what molecule, in what way. This molecule fits in there so it can react. So it's, you know, held in place so it can react with another molecule, et cetera, et cetera, et cetera. That's a very, that's very common. That's a lot of how we work inside, so to speak, at the molecular level. Okay, so now you build this molecule, and people try and figure it out with computers, with, with, with all kinds of things. They'll test all kinds of different sources of molecules and things. They'll say, what's a molecule that correctly gums up that hole? Great. Okay. They find such a molecule, and then they say, okay, that's good. Now the question is, it has that effect, but is there anywhere else in the body where it might sort of gum up a different hole that wasn't the one you intended to gum up or might attach to something different that wasn't the one you intended? Well, that's the first question. Second thing is we all have the molecules, the proteins that we're made of. They're all a little bit different between different ones of us because our DNA, our original genetic material, is slightly different. And that means there will be small differences. One, you know, tiny region, one amino acid and a protein. The proteins are chains of amino acids. They might be a chain of a thousand or a million amino acids, maybe. Yeah, actually, the biggest ones are that size, but, you know, hundreds to thousands to tens of thousands of amino acids. And, you know, the different people will have individual pieces of those chains that are different. And so the, the issue Is if you have made this wonderful molecule, this wonderful drug that you say, oh, yeah, it fits right in this hole for a protein. Where I tested that protein, you say, well, what about somebody else's version of that protein? Maybe that will have an extra little latter ledge on it. And that extra ledge will prevent the molecule from sticking in. Or maybe they'll see some completely different protein that's somewhere completely different in the body where that drug molecule will somehow be able to attach to that completely different protein. So that's a common reason why there are sort of side effects, is that the thing that you thought was going to only, you know, sort of attach to the molecule we thought is only going to attach to one thing actually attaches to other things instead. And there are other reasons for side effects. I mean, there are sometimes side effects are not very well understood. And it's. There are a lot of side effects. Some of them happen quickly, some of them happen slowly. Some of them gradually build up. If you take too much of this drug over a long period of time, some system in your body will go out of balance. Because it was sort of expecting one thing, but it was continually getting another thing. There are other things that can happen in the more physical characters, pieces of the body, things like the kidneys where you're filtering the blood and so on. The little very fine, sort of fine mesh of the filters can be damaged by molecules of different kinds and so on. Same things can happen in. When the lungs, if you're inhaling stuff and so on. There are all kinds of detailed sort of physical effects that can happen. And one thing that happens is because, well, not only are our detailed molecules different, there are also differences in the sort of physical setup of, you know, the details of the kind of. The little kind of branches and lungs or something might be different. They might be different in one person from another because of a difference in the environment that they're in. They might have all kinds of reasons why there's differences. And so that means that the thing that was tested on a thousand people and it says, okay, great, this works perfectly for a thousand people. And they never had any bad effect. The thousand and first person might have a different enough set of molecules or different enough physical setup about some part of their body that the molecule has a different effect on them than it does on all the people who are tested. And so then you would have what would normally be called a side effect of some kind. That was something that wasn't expected. I think it's one of these things that it's really inevitable that there will be unexpected effects. It's kind of a consequence of sort of pretty deep kind of ideas about sort of the way that. The way that things work and sort of computation and so on, that there will always be these sort of unexpected effects. And it gets more complicated when the thing that you're using is not just a single molecule, a drug that's just, okay, we've got this molecule that's a drug. But let's say you have this drug that's really clever and it's sort of an algorithmic drug where it can compute things and adapt itself even at a molecular level. Then you ask, well, could there be a side effect? And then you're really asking something that is very much like you're debugging a program. There's this molecule that's sort of flapping around like a, you know, executing a program, and you're saying in its interaction with this whole environment that is us, could we end up with some place where we essentially see a bug in this program that will be found for this one in a billion people type situation? So that's a slight idea of how that works. Let's see, there's a question here. Why do we yawn? Are yawns truly contagious? A couple of things to say about that. I think the reason one yawns is that the. In the, you know, we're trying to get into our lungs oxygen, which is about 20%. 1/5 of. Of air is oxygen. That's the part that matters to us in terms of running our bodies. And we're trying to get oxygen into our lungs by breathing in air. And we're trying to get sort of enough oxygen down to all those layers of branching there, like 23 layers of branching in the lungs from really big sort of the big sort of windpipe in our throats down to little tiny, tiny branches that eventually gets small enough that the oxygen in the air in our lungs is so close to our blood that it's within 2 millionths of a meter, 2 microns. That the oxygen molecules can diffuse through these membranes into our blood and can be picked up by hemoglobin and our red blood cells and so on and can be transported around our body to provide the sort of the raw material. The oxygen is part of the raw material for metabolism, for the chemical reactions that happen in our body. So we need a certain amount of oxygen. And I think the usual claim for why we yawn is that if the carbon dioxide level, which is, you know, we inhale oxygen, we exhale carbon dioxide. If we, it's not all carbon dioxide that we exhale, but there's more carbon dioxide and what we exhale and what we inhale. But what we inhale is actually a hell of a little sensor. I think even I can say that it's, let's see, 500 parts per million. I think, I think it's in parts per million right now, right here, so to speak. But in General it's like 400, 500, depends where you are. If you're inside and there's lots of people, you're in a room and it's full of people breathing out and there's no fresh air coming in, you'll. If you take a carbon dioxide meter, you'll see it climbing up. It'll get to a thousand parts per million, I think, and go beyond. When you're in a stuffy room, so to speak, people are breathing out a certain amount of carbon dioxide, breathing in oxygen. I think the claim is that one yawns because somehow one's brain is sensing sort of there's too much carbon dioxide, we need to gulp in more, more oxygen. Quite why that relates to being tired, I'm not quite sure. I'm not sure. As I tell you that explanation, which is one that I've heard over decades ago, I'm not quite as convinced by it as I might be, but that's, I think, the traditional explanation. Now are yawns contagious. You know, everything is somehow contagious. There are in our brains sometimes people call them mirror neurons. There's definite sort of circuitry in our brain that says if you see somebody doing something, you imitate what they're doing. That's probably a very important piece of how we learn as, as babies, so to speak, how we learn how anything works. If we didn't have that sort of built in circuit that like do what's what, you know, do what you're seeing, so to speak, that it will be very hard for us to learn things. We kind of learn by imitation in the first level. So it's very common. If you're, you know, if you're talking to someone, you notice it all the time. You know, somebody will adjust their glasses and then the person they're talking to will adjust their glasses. If they have glasses or somebody will do something and the person they're talking to will kind of reflect that in what they do. And that seems to be a thing that is kind of a vestige perhaps of something which is important for very early Life for humans of learning things. Maybe it's something that's part of the way that sort of social interaction works in even adult humans. I'm not sure. Maybe it's part of kind of how humans realize that they're kind of in sync with each other. Oh, that person just did something like what I did, so they're paying attention to me, so to speak. Maybe the lack of that in some situations with virtual. In some virtual situations might be why. How one. I think that might be a little bit. How one knows that somebody sort of isn't paying attention is that they're not reacting. And sometimes that reaction is an imitation of what they're seeing, so to speak. So I kind of suspect that the contagion of yawns is a contagion of everything. It's probably a contagion of, you know, scratching one's ear. And it's a contagion of other things too. I don't think it's any more. My guess is that it's contagious because of this generic sort of imitation characteristic rather than something else. Let's see. Oh, boy. Lots of good questions here. There's a question from Jamie. Why do cats meow? Dogs bark? Birds chirp? Well, you know, I, I gather that the cat's meow is an evolved trait. If you look at wild cats, they have a different sound. The, the, the expectation is that domesticated cats are. The cats are not, I don't know, they're not as domesticated as some other animals. But, but the somewhat domesticated cats that we have and the breeds of cats people have produced and so on, that part of their sound has been adapted to be sort of happy to be around humans. Just like I think cats by nature sort of tend to run away from everything. And the ones that are the domesticated version, like hanging out with people, which probably isn't their natural way and so that, that term. But in terms of, of these different sounds, you know, one thing to realize is part of the sound of an animal has to do with how big it is. Just like with humans, you know, young kids will have much higher pitched voices because when the air is being sort of vibrated in their, in their vocal cords and their throat, the size of the region is much smaller. And so that leads to much higher pitched sound. Just like if you have a string with a stringed instrument or something, the little tiny piece of string will make a much higher pitch than the big long piece of string that vibrates more slowly and makes a lower pitch. So the kind of the smaller the animal, the smaller the throat of the animal, so to speak, where the sound is being made, the higher pitch the animal will tend to have. And when you get what might be a purr in a cat, in a domestic cat will turn into a roar. And a lion, just because even though the lion has sort of the same circuitry potentially as a cat making a purr, the purr turns into this much lower frequency rumbling in the bigger lion, so to speak. Now I think that different animals have different characteristics in their, in their vocal tracts and their throats and the, where, where the air goes into their lungs. Like we humans have vocal cords which have very detailed control by, by our nerves that allow us to make the sounds that correspond to, to, to speaking. And you know, that's, that's part of the story. The other part of the story is how we form our mouths to make different kinds of sounds. Like we might make an s. Hissing sound. That hissing is turbulent air in our mouths being sort of forced through a small gap. And in sort of phonetics there are all these different names. You know, glottal stops. That's a thing when you close down your throat and then labials, that's, I think from the front l L labial. It has to do with rolling your tongue out into the front of your mouth and so on. And those are, you're generating sort of a, you're generating the sound in your vocal cords and then it's being sort of adapted by what's happening in your mouth. Now birds, for example, have a different setup. They have a thing called the syrinx. And birds are able to make, for example, we can just make a single, you know, when you sing, you typically make a single note. That's, that's what you know, you're, you're, you're going, you have a single, it's not, it's not all precisely concentrated at one frequency. It's not a pure tone. But you're making, you know, you sing one note, then another note, another note. Birds can effectively sing two notes at a time. As much like, you know, on an old fashioned touch tone phone, you always have two frequencies. One for the sort of horizontal position of the key, one for the vertical position. That's kind of like what birds chirp. They chirp sort of two frequencies at a time different from what we humans do. So there are these different sort of different structures in the vocal tract in the throat of these different animals that lead to different kinds of sounds. And I think in terms of whether there is A sort of evolutionary value, like I mentioned with the cats, as they become domesticated, their meows and things have apparently become adapted to being around humans. And so one might ask, what was the adaptation that led to different kinds of sounds for different kinds of animals? For birds? I think the, there are a certain, you know, a common thing with certain kinds of animals is, you know, it's kind of like the uuid of the animal. It's like I'm going to chirp just this way and so, you know, it's me, so to speak, or this, you know, with birds there tend to be these kind of seasonal fashions, very much like with humans where there'll be a song and the song will start, become popular, it'll go to the top of the bird charts. All the birds will be chirping that song for a season and then the next, the next song will come around next season. It's kind of shocking how similar to sort of the human condition that really is. I do remember when I was a kid in England, the, the phones that they were always in those days, it was the government, you know, the post office as it was, as it was, sort of operated all the phones. And so you got sort of the government phones. And there were a limited number of kinds of phones, same in the US until, until the bell system was, was, was broken up in the 80s that, you know, there were a limited number of kinds of phones. But anyway, one of the things that there was this sort of, there had been phones which just rang a bell, so to speak, when they, you know, when the phone was ringing, it was, you know, it was just something hitting a sort of bell type thing to make the, make the sound, to tell you there was a phone call. But then in a piece of modernity that turned into an electronic kind of synthesizer and it made more of a, you know, I can't imitate it type sound. And the funny thing was that over a summer the birds heard those sounds all over England and birds started making those sounds and it was super confusing because you would hear that sound and it's like, is that a bird? Is that a phone? You couldn't tell. Anyway, just an amusing thing that happened that was sort of an adaptation of the birds to their environment, the phone environment, so to speak, that one was able to see over that short of timescale. M asks, why can't AI help us analyze animal sounds? A lot of people thinking about that right now. There is a certain extent to which it can. I mean, you know, we've even done Experiments from. From looking at some. I've always been curious about this question about sort of communicating with alien minds. And, you know, the animals on the Earth are a great example of kind of minds different from our human minds. And so, you know, you look at whale songs and things like this, and you say, can you recognize the phonemes, the lumps of sound, the repeated lumps of sound? Yeah, you can recognize those kinds of ph things. Can you recognize sort of phrases? Can you recognize repeated phrases? You recognize things at that level of structure? The answer is yes, and you can pick those things out pretty easily with AI. The next question is, can you associate what. When a whale goes whatever. Whatever a whale does when it or a bird chirps in a particular way. But let's take a whale, because they seem to be probably communicating in a way that's more obviously like language. You know, what does it mean when it makes this particular kind of whale song sound? Well, for that, we have to associate kind of. We have to know, just like if you're trying to learn some language, somebody has to show you an apple and tell you that that is a particular word in the language you're trying to learn. So similarly, in the case of the whales, it's like, okay, we hear a whale sound. What does the whale mean by that whale sound? Well, potentially we get to correlate the behavior of the whale with the sound they make, and perhaps we can figure out what that sound means. Nobody's managed to do that yet, but there's a hope that even in the fairly near term, there's lots of data being taken that that may be something that becomes clear. Now, it's a tricky business because the whale doesn't do things that are like what we sort of terrestrial humans with hands and all that kind of thing tend to do. So for the whale, it may be saying, you know, don't you know, there's this ocean current that goes this way and it has a weird corkscrew, you know, effect, and et cetera, et cetera, et cetera. And that in whale is some, you know, complicated sequence of whale sounds. And we just see the whale sounds. We see the whale, it's swimming around, et cetera, et cetera, et cetera. We never know to go check the velocity field of this thing and see whether it has some variance across the, you know, the left flipper and the right flipper of the whale and things like that. We don't know what it, you know, we hear that sound, but we don't know what it's to be correlated with the same kind of thing. When people have measured in, for example, cats, people have measured the. In the neurons in the visual cortex of the cat. They measured kind of the effect of different visual stimuli. And some visual stimuli, like you can tell, oh, yes, that neuron fires when the cat sees a black blob. That neuron fires when it sees a black blob with white surrounding it. That one fires when it sees a vertical stripe, that one when it's a horizontal stripe, and so on. And then there are neurons that you see firing when it's. When the cat is just looking at some visual scene, but you don't know why they're firing. You don't know what feature of the visual scene made those neurons fire. And I think it's the same kind of thing with trying to correlate kind of the sounds, the vocalizations of animals with their sort of environment. It's like, well, what part of their environment should we be paying attention to? And potentially, if we have sensors that sort of replicate the sensors on the whale and we feed all those sensors to the AI, it might have a chance of picking up whatever it was that the whale sensed there. But, you know, if the whales are debating philosophy across the Pacific Ocean or something, because their sounds carry a long way in the deep ocean. If they're debating philosophy, whale philosophy, good luck to us in decoding what on earth is going on. Or if they are, you know, telling. You know, if they're like the Homeric bards or something, telling the. The epic story, maybe they're telling their side of the epic story of Ahab and Moby Dick or something like this, and they've been telling it for the last. Whales live a long time. They've been telling it for the last couple of centuries or something back and forth. And we'd have no idea how to correlate that with sort of the. Oh, yes, this whale sensed this particular thing that we can detect. The whales saw a giant squid, and it's telling all its other whale friends, did you see that giant squid? I've never seen one as big as that. Well, you have a hope. If you have a sensor that's watching what the whale's eyes see, and they can. You can see that it saw a giant squid. You have a hope of being able to correlate that. But that's a. That's a complicated thing. Let's see, Let's see. Here's one that maybe is simple. That's always dangerous. When I say that from tenacious, do Photons run through antimatter. Does that make them matter? Okay, so what antimatter always is, is you have something like an electron. It has a certain mass, it has a certain charge. The antielectron has the same mass as the electron, but it has the opposite charge to the electron. And so when an electron and a positron, which is an anti electron, meet, they can. That you need to. The result is there's a plus charge and a minus charge. And whatever they turn into has to have zero charge. And or at least the total charge has to be zero. They typically will turn into a bunch of photons. Photons have the feature that they are their own antiparticle. Photons don't have any charge. And so an antiphoton is just a photon. So when a photon encounters antimatter, it's just, it's like, okay, this is an electron, this is a positron. Okay, I do what I do when I encounter an electron like thing. It's no different between encountering an electron and encountering a positron. And so, for example, if you were to have a beam of electrons and a beam of photons and they interact and you get various kinds of scattering between the photon beam and the electron beam, it'll scatter. In one way, you do the same thing with positrons. Exactly the same effects will be exactly the same. In fact, so far as we know those two things, there could be a difference because of the details of how quantum field theory works. If you're running sort of forwards in time and you're looking at that scattering process, it could be the case that for an electron and a positron, there was a slight difference in what you would get. It seems that that isn't true technically. It means that charge conjugation is the electromagnetic force is invariant under charge conjugation symmetry. And that's sort of a fancy way of saying it doesn't care whether it's the. The photon just doesn't care whether it's interacting with an electron or a positron. It does it in exactly the same way. So that, that's why photons don't. That they're their own antiparticle. They, they don't care. Let's see, Des asks, is chemistry really just physics? It's an interesting question. Back in the day, this chap called Ernest Rutherford, the guy who discovered the atomic nucleus, was rather disparaging. He thought of himself as a physicist and rather disparaging. He said, really, there are two branches of science. He was Thinking of physics and chemistry. He says there's physics and there's stamp collecting. By that, he meant that in physics there are systematic laws, and we can learn a small number of systematic laws. In chemistry, it's like there are all these different things and all these different molecules, and it's like collecting stamps from around the world. It's kind of like there's no regularity, there's no principles in it. It's just all. It happens to be this, it happens to be that, and so on. Well, so, interesting claim and quote. Well, let's talk about what chemistry is about. Chemistry is about the interactions between atoms and molecules and so on. And those atoms and molecules are described by the quantum mechanics of physics and so on. In principle, you can compute what happens given the laws of physics. You can in principle work out the structure of a water molecule. You can in principle work out what will happen when this molecule crashes into this molecule, et cetera. In practice, it's really hard to work those things out. Even after all these years, with all the computational tools we have, we can't work out that much about the structure of, for example, anything but fairly small molecules. And when it comes to how molecules collide with each other and react, there's surprisingly little that we can actually work out in practice. With the computers we have today and with all the techniques we have nowadays. There's a lot of machine learning techniques that are useful for being able to sort of remember different sort of fragments of how things work and fit them together. We have a hard time sort of actually working that out from the physics. In principle, we could work out, we think we can work out how all these things in chemistry work, but not in practice. And there's this phenomenon I call computational irreducibility, this idea that once you know the rules for a computational system, it may take you actually just explicitly following those rules step by step by step to work out how that system will behave. There may be sort of no fast way to jump ahead and see what happens. And I think that's what chemistry basically is. It's physics and computational irreducibility. So there's physics underneath that says, yes, these are the detailed rules by which the individual electrons and individual atoms work. But by the time we try and aggregate that up into. So what's the property of this big molecule with a thousand atoms in it? That's something that's a computationally irreducible thing to work out. It takes sort of an irreducible amount of computational effort to figure that out. And so that means in some sense that while chemistry is in principle derivable from physics, in practice there's this irreducible computational barrier in describing chemistry from physics. So in that sense, chemistry really is in some sense as separated from physics. Well, in some sense, when we think about our own minds and how we work and whether we have free will and, and how we decide to do this thing or that thing, those things are also ultimately determined by physics. But that's not how we think about them. We feel we have free will. We feel we have something that is sort of irreducibly distant from the underlying physics by which we operate. And I think it's sort of the same thing in chemistry. A little bit less distance than perhaps with human minds, but there's still, there's a distance and it's sort of this irreducible computational distance. So there is something sort of fundamentally different about the chemistry that we look at. That is, as Rutherford called it, these sort of stamp collections of all these different things that happen in chemistry versus what happens in physics. Now the question is, are there principles in chemistry as there are principles in physics? Well, the problem is that since chemistry is built on top of this computational irreducibility, that kind of tells you right there that there will be less principles, that there will be. There'll be some principles, but there'll be things that are hard to work out from principles. There are things where you just have to have measured it and see what happens. Because in a sense, to say there's a principle is to say you can jump ahead of this computational irreducibility. And that's something which there's always pieces of reducibility. There's always places where you can jump ahead, but there can be a big sort of ocean of irreducibility. And I think that's kind of what you see in the kind of stamp collecting aspects of chemistry. Now I think that there are things about chemistry that there are principles of chemistry that perhaps are, well, chemistry. There's so much in chemistry that is not really that well understood. Now. It's interesting how fields work. You know, chemistry had a really golden age in the late 1800s. People were discovering all these different kinds of reactions and figuring out all these different ways to make things. And then again, when plastic and things got invented, 1920s, 1930s and so on. So another kind of big sort of burst of chemistry. Physics had this big burst of activity in the 1920s particularly, and these were sort of different bursts of activity. I think, you know, chemistry is probably due for another Another burst of activity. And it might even relate to. Well, one of the questions is when we describe sort of what's happening in chemistry, by what means do we describe it? The typical way you describe chemistry is, oh, they're these chemical reactions, they're these molecules, they're sort of randomly bouncing around. In a gas and a liquid, for example, they're sort of randomly bouncing around. Every so often two molecules will collide. If the molecules are in the right orientation and so on, they'll stick into each other and there'll be a chemical reaction and they'll turn into other molecules. And you know, I think that there are sort of questions about, well, if the traditional view of chemistry is just there's a rate of reaction that's just all these molecules are randomly bouncing around. My guess is that particularly when it comes to molecular biology to sort of chemistry of life, that there are other effects that are quite important that have to do with, well, these two molecules collided. Those same two molecules might meet each other again, you know, a millionth of a second later or something. But that's not something accounted for in traditional views of chemistry. This kind of causal graph of which molecules interact with which molecules is something that isn't really thought about. It's all kind of randomized. And so, you know, there are things like that. That's one kind of area. There are things that. There are a lot of reasons why I think there's a chance that some sort of exciting principle based things might happen in chemistry in the not too distant future. And certainly the sort of merger of thinking about molecules as things that can compute and so on is a whole other direction to chemistry. Let's see, maybe a few more, Let's see people asking, does brain size have any correlation to iq? I think the answer is no. I think that, you know, it well, there's several points. First, the notion of IQ is a very funky notion. It's a notion was invented about 100 years ago as kind of a, a, you know, we can measure the height of a person, we can measure the weight of a person. Surely we can measure something about the mental functioning of a person. And surely we can get one number that characterizes that, just like we can get one number which is the height of the person. Well, really, if we really wanted to be persnickety about it, we wouldn't have just one number that's the height of the person because it depends on, you know, are you measuring it? You know, is it the really tippy top of their head or is it you know, is it at this angle, is it at that angle? But we kind of know there's one number that characterizes the height of a person. The question is there's sort of one number that characterizes something about the thinking processes of a person. The answer is quite plainly no, which is hardly a surprise. And it's like saying, I have a computer or a program on a computer. Can I characterize, is this program sort of, can I give one number that characterizes, oh, this computer is sort of, is this effective? And that computer is that effective? I can't really do that. There are things like the clock speed of the computer, the amount of memory the computer has, those are things you can measure. But the sort of ability of the computer is something where there isn't just one number that measures it, nor is there with humans. And it tends to be kind of a put up job because you can make an IQ test, so called IQ test. And you know, the IQ test has a particular form, you know, you'll say, what's the odd shape out in this picture? Et cetera, et cetera, et cetera. And if people have never seen those before, there's a certain, oh yeah, I can figure this out. And people who have seen things like that before will be able to do it faster than people who haven't. And people who, who really practice on those kinds of problems will be able to do it much better and so on. There's a, there's. But it's also the case that there tends to be this kind of baggage associated with, oh, I can do this odd thing out in this, you know, picture of blocks and so on. I can do that really well. So I'm really quotes generally smart and I'm going to be able to solve these big problems in. When it comes to, I don't know, working out the strategy for some company or something like that. I don't think it works that way. I think that our brains, like computers and so on, are very. They have lots of different abilities which are determined probably to some extent by the hardware of the brain and to a large extent by kind of what the brain learned and also how the brain is exercised, so to speak, what, what it learned and what it learned to learn and all those kinds of things. When it comes to the raw hardware of the brain, every brain is different. Brains are much more different than fingerprints. The kind of foldings of brains are even. Each different person has a different characteristic folding of their brain and so on. What effect that has, I don't think anybody knows there are certainly examples where people had various kinds of diseases where their brain was kind of crushed into a pretty small volume, but that didn't really affect their sort of ability to think with their brain, so to speak. There are cases. I mean, it's pure brain mass is unlikely, I think, to be. I don't know. I'm sure there are. Will be an interesting question. What behavioral characteristics of a human can you identify that would be correlated with straight brain mass? I don't know. I don't think that's a known thing. I think that. I also don't even know. I mean, there's sort of a question of is a bigger brain better? Not obviously true. You know, it takes longer for signals to go across a bigger brain. Maybe if you want to have coherent thoughts, it's better not to have a bigger brain because, you know, in a bigger brain there might be more different things going on that are incoherent with each other and you wouldn't be able to sort of form as clear a chain of thoughts. So, you know, I think it could go in many different directions and I, I'm not aware of. Of that. Of that feature, I think. Yeah. Zayden is commenting. The hardware of the brain is an ongoing process, especially in childhood. Nurture, environment, society, et cetera. Can cause changes in brain hardware. Yeah, I don't know. I mean, certainly in things like the neurotransmitters, the actual sort of chemicals that are produced in the brain. Absolutely. There are things like, you know, if you have lots of stress for a long time, it can affect those kinds of things or all sorts of things like that. I'm not sure that it's really known what effect. Maybe it's known from animals like mice and so on. What effect on the actual individual neurons in a brain. Different kinds of environmental features have. I think there are certainly things known about, well, diet, for example. I mean, famously the. Oh, in the potato famine of 150 years ago or something, there was. That led to vitamin A deficiency, I guess, which led to retinal damage, which led to. Which I think is partly heritable. There's a weird case where what happens to one generation during the course of their life can affect the next generation. But I think there are things like that where, I mean, the retina in the eye can certainly be affected by those things. I don't know what. Yes, there must be. Well, I know there are. There are all sorts of terrible things that happen when, you know, when, when fetuses are exposed to drugs of Various kinds. There are all sorts of bad things that can happen that affect brain chemistry. I don't know whether they affect brain structure. I know they affect brain chemistry and the neurotransmitters and so on, which are, which are kind of sort of small, smaller molecules that, well, they're molecules that kind of can diffuse around in the brain rather than the actual sort of structure of neurons with dendrites and things like that. And I don't think it is certainly known, it was for a long time believed that for humans, you're born with a certain brain and all that ever happens is neurons die over the course of your life and you never get new neurons. Eventually it was discovered that that's not true, actually. And there are new neurons that can be produced even in the adult brain. And some of us who pride ourselves on using our brains quite a bit have the at least idea that if you use your brain a lot, maybe you'll grow new neurons. Just like, you know, if you use your muscles a lot, you'll grow bigger muscles and you'll get more, more pieces of muscle filament in there. I don't know if this is true. I don't think anybody knows whether that's true at this point. But it's kind of a fun thing to imagine, at least. Yeah, spare parts ask, do bigger brains actually have more functional neurons or are they just more spread out? I do not know. I don't think it's known. It's only very recently that people have good estimates of the number of, of neurons in a human brain. And the estimate I keep on persistently seeing is 86 billion. And I, I, I would be very, very surprised if that number is, is that constant. I would, I would guess that that number will vary by, I don't know, 10% or something. In a brain, just like human heights and things vary by, well, what is it? It must be more than 10%, 20, 25%. So I think it's my guess is that that won't be a constant number. But it's only been rather recently, surprisingly recently, that one's been able to sort of essentially dissolve a brain and keep the neurons intact and count the neurons. And in the past, it had been more like you take microscopic slices of brains and you try and count the neurons there. But that's really hard to do because neurons are long, spindly things and it's hard to know. You have this microscope slice here. Oh, and by the way, neurons also are, they tend to be sort of semi transparent. One of the Weird tricks is this thing called Golgi staining, where you put a chemical into something like brain tissue and one in a thousand neurons turn purple. Nobody knows which characteristic the ones that turn purple have that distinguishes the others. But it's very useful because that means you can kind of see sort of. There's a sort of background of semi transparent stuff, and then you see this one purple neuron sort of snaking through, and you can kind of see the shape of it. But it's been really hard to count neurons that way, I must say. I've been asking people for, like, decades, why can't you just dissolve the thing and just have the neurons kind of come apart and count them? And people have always told me, oh, you can't do that for this reason or that reason. But I noticed in recent years, people have done that in some way. All right, I should wrap up in a moment here. Yeah. So. Oh, yeah, the question asked here was, do bigger brains have more functional neurons? Are they just more spread out? I don't know the answer to that. I'm guessing there's a variation in both of those things. I know that there are situations in which you get. Yeah, I. I simply don't know the. Let's see. Wes asks, returning to a another question. Would all whales speak the same whale language? I suspect the answer is no, and I think it's even known that the answer is no. The only thing about whales that's weird is that because they communicate using sound in the ocean and because, you know, in air, for example, sound doesn't carry that far, and still air, maybe you can hear somebody, I don't know, 100ft away, something like that. But in the ocean, in the deep ocean, where it's very still, there are these kind of wave guides. So normally in sound, it's, you know, you make a sound and the sound waves are kind of going out in all directions. So if you go that, the intensity of the sound goes down like the square of the distance, because that's the area of the kind of shell of where the sound gets to in all different directions. In the deep ocean, there are essentially waveguides that keep the sound going in one tube in the deep ocean, just in the water. In the ocean, that comes about because of the changes in the salt level and the changes in the temperature and so on in the ocean keeps the sound sort of bouncing back and forth. In this kind of waveguide, it's a little bit similar to the way that fiber optics keeps light bouncing back and forth inside this little optical fiber of glass or whatever. And so that means that whale sounds can carry a long way, like across the ocean, across the Pacific Ocean. Same is true. You know, that's the way people. Like in the U.S. for example, on the East coast of the U.S. one knows that there's a hydrophone array which is kind of listening for shipping in the Atlantic. And if there's a ship that goes through the Straits of Gibraltar, if it isn't a very special kind of ship, you can hear that from the hydrophone array on the east coast of the US because in the deep ocean, the sound from the propeller of that ship sort of carries all those thousands of miles. And so for whales, similarly, there is a. You know, the whale on one side of the Pacific Ocean can be heard by whale on the other side of the Pacific Ocean. So, you know, globalism probably came to the whales a lot earlier than it came to the humans in the sense that the, the number of distinct sort of separate conversations that can be happening is. Is probably smaller because sort of the. Each conversation carries further. It's. But I, I think I, I vaguely remember that there are distinct kind of. I know there are seasonal changes of the whale songs. I think there may be regional ones as well. Certainly among birds, there are plenty of regional changes. And that's, you know, there are different dialects of different songs sung by songbirds and things like this. And my guess is there are different dialects of whale. I don't, I don't know for sure. And. But as I say, there's this effect that sort of globalism came to the whales before it came to the humans. Okay. Wampus is noting that they had a friend as a bird that learned to imitate their microwave alarm. Yep. Well, it's, you know, these neural nets that are in brains and that in birds and other brains, they learn. And they learn to, you know, this is, this is the interesting feature of this sort of concept of neural nets that. That's sort of key to our brain's work. All right, I think we should probably wrap up now and. Well, this was, this was fun for me and you guys asking all kinds of questions that, as I say, sometimes the. The ones that sound simplest are the ones that are most tricky to answer. But I've. It's been interesting to. To try and do some of these here today. All right, well, thanks for joining me and see you again another time. Bye for now.