WEBVTT - TechStuff Classic: The Manhattan Project Part One 0:00:04.400 --> 0:00:07.800 Welcome to tech Stuff, a production from I Heart Radio. 0:00:11.800 --> 0:00:14.400 Hey there, and welcome to tech Stuff. I am your 0:00:14.440 --> 0:00:16.720 host job in Strickland. I'm an executive producer with I 0:00:16.800 --> 0:00:20.320 Heart Radio and how the tech are here. It's time 0:00:20.720 --> 0:00:24.400 for a tech Stuff classic episode. This episode originally published 0:00:24.480 --> 0:00:30.560 July fifteen. It is titled The Manhattan Project Part One, 0:00:31.280 --> 0:00:33.360 So I bet you can guess what next week's classic 0:00:33.400 --> 0:00:36.640 episode is. This episode had been bolan of stuff they 0:00:36.680 --> 0:00:39.920 don't want you to know, and Ridiculous History joined the 0:00:40.000 --> 0:00:43.600 episode to talk about the Manhattan Project. We really get 0:00:43.600 --> 0:00:47.279 into the physics in this one. Hope you enjoy. I 0:00:47.320 --> 0:00:50.680 don't want to disparage the gravity of what we're doing 0:00:51.760 --> 0:00:55.760 anything less than a few tangents or puns in this story, 0:00:55.840 --> 0:00:58.600 because this is a fascinating story. It's a fascinating story, 0:00:58.680 --> 0:01:01.800 and and you can't get around the fact that the 0:01:01.920 --> 0:01:07.080 end of the story is massively tragic, right like, like, 0:01:07.120 --> 0:01:09.560 there's there's a ton of things that we can talk about, 0:01:09.600 --> 0:01:12.000 and what we are talking about is the Manhattan Project. 0:01:12.080 --> 0:01:13.479 And I'm gonna go ahead and let you guys know, 0:01:14.000 --> 0:01:16.319 this sucker is going to be a two parter because 0:01:16.360 --> 0:01:18.959 in order to cover the Manhattan Project. You have to 0:01:19.000 --> 0:01:21.320 have an understanding of what was going on in physics 0:01:21.400 --> 0:01:24.600 leading up to the beginning of the project, which will 0:01:24.640 --> 0:01:27.840 be this episode, and then there's another episode that will 0:01:27.880 --> 0:01:31.000 be all about the actual developments of the project itself. 0:01:32.000 --> 0:01:36.120 And this is complicated for multiple reasons. One, nuclear physics 0:01:37.040 --> 0:01:40.840 not straightforward as it turns out. Yeah, actually lots of 0:01:40.880 --> 0:01:43.080 pressure because of the implosion technique, but we'll get into 0:01:43.080 --> 0:01:47.040 that in episode two. Also politics, a lot of politics. 0:01:47.280 --> 0:01:50.480 I mean, obviously, the Manhattan Project was formed as a 0:01:50.520 --> 0:01:54.040 result of World War Two. If World War Two had 0:01:54.080 --> 0:01:57.520 not been happening, the Manhattan Project probably would not have 0:01:57.560 --> 0:02:00.880 been formed, and nuclear power may have either been pushed 0:02:00.920 --> 0:02:04.240 back by quite a bit or someone else would have 0:02:04.520 --> 0:02:07.400 ended up developing it ahead of the United States. So 0:02:08.960 --> 0:02:12.760 both of those things. Science and politics by themselves are complex, 0:02:12.800 --> 0:02:14.720 and when you combine the two and you try to 0:02:14.760 --> 0:02:18.359 make science work within the realm of a political structure, 0:02:19.480 --> 0:02:22.440 it gets messy. Yeah, and not not in like a 0:02:22.520 --> 0:02:24.880 cool I got my hair cut at a nice salon, 0:02:25.240 --> 0:02:28.160 Look at me. Messy. No, not like rolled out of bed. 0:02:28.720 --> 0:02:31.239 Oh this didn't take me any time at all, right, 0:02:31.360 --> 0:02:35.359 messy as in uh is a massive loss of blood 0:02:35.360 --> 0:02:38.440 and treasure. I think we're looking at the equivalent of 0:02:38.639 --> 0:02:42.520 when it got rolling thirty billion dollars you you know, 0:02:42.919 --> 0:02:45.960 in money. All yeah, today's money. It all depends upon 0:02:46.040 --> 0:02:49.120 the well, it really depends upon how you define the 0:02:49.160 --> 0:02:52.720 scope of the project. Because that's something else that's kind 0:02:52.720 --> 0:02:57.040 of confusing, because you hear Manhattan Project and you think, okay, uh, 0:02:57.160 --> 0:03:01.839 Manhattan Project, that's the one that took place in oak Ridge, Tennessee, Hanford, Washington, 0:03:02.080 --> 0:03:07.200 Los Alamos, New Mexico. Makes sense. We will explain all 0:03:07.240 --> 0:03:09.600 of that as we go through. So in case you 0:03:09.680 --> 0:03:12.000 weren't aware, the Manhattan Project was the code named the 0:03:12.040 --> 0:03:16.799 United States government gave to the the effort to design 0:03:17.120 --> 0:03:21.400 and build an atomic bomb for use in World War two. 0:03:22.000 --> 0:03:24.320 And in order for us to talk about we have 0:03:24.400 --> 0:03:26.720 to go back way before World War two. In fact, 0:03:26.760 --> 0:03:29.840 we have to go back before World War One. Yes, yeah, 0:03:29.919 --> 0:03:32.280 we have to go all the way back to the 0:03:32.560 --> 0:03:36.480 I guess the end of the nineteenth century, that is correct, 0:03:36.800 --> 0:03:40.560 late nineteenth century. Uh, there was a fella by the 0:03:40.640 --> 0:03:44.480 name of Henrie Beccarell alright, who had made an interesting 0:03:44.520 --> 0:03:51.320 observation observing that some material when placed against some plates 0:03:51.560 --> 0:03:56.280 would create a negative image. And he had assumed that 0:03:56.320 --> 0:04:00.600 this material was phosphorescent, that it absorbed light and then 0:04:00.720 --> 0:04:05.520 given off some form of ray to create this image, 0:04:05.600 --> 0:04:09.840 but later determined that he was mistaken, that there was 0:04:09.880 --> 0:04:12.520 no need for the sunlight. The stuff was giving off 0:04:12.600 --> 0:04:17.640 the rays by itself. And then you had the Curies 0:04:18.040 --> 0:04:21.440 coming along, who who went on to study this themselves. 0:04:21.800 --> 0:04:27.560 Marie Cury coined the term radioactive radioactive with the word 0:04:27.800 --> 0:04:33.440 ray in it. And so at this point there was 0:04:33.480 --> 0:04:37.120 an understanding that certain elements had a type of energy 0:04:37.160 --> 0:04:42.280 they could give off spontaneously, spontaneous radiation. And that is 0:04:42.400 --> 0:04:47.880 the beginning the nub, that the kernel that forms the 0:04:47.880 --> 0:04:53.839 the very center of the Manhattan Project's purpose. So building 0:04:53.880 --> 0:04:57.640 on that we then have there's a guy in Nive. 0:04:58.080 --> 0:05:00.680 He had a little theory. It was a special theory, 0:05:00.720 --> 0:05:05.080 I mean relatively special man. Yes, yes, And that that 0:05:05.200 --> 0:05:10.840 man you may know today through countless Internet memes Albert Einstein. Yes, yes, 0:05:11.680 --> 0:05:17.400 Albert Einstein, al to his friends, was a brilliant physicist, obviously, 0:05:18.000 --> 0:05:20.360 and it was all the way back in n when 0:05:20.400 --> 0:05:25.080 Einstein proposed the special theory of relativity, which, among many 0:05:25.160 --> 0:05:30.200 other things, positive that energy and matter are pretty much interchangeable. 0:05:30.520 --> 0:05:34.680 And this is where the the famous equation E equals 0:05:34.960 --> 0:05:39.799 MC squared comes from. The E means energy, the M 0:05:39.839 --> 0:05:44.320 means mass. The C squared C stands for the constant 0:05:44.400 --> 0:05:47.240 of the speed of light through a vacuum. Keeping in 0:05:47.279 --> 0:05:50.280 mind that light actually can travel at different speeds depending 0:05:50.360 --> 0:05:53.400 upon the medium through which it travels. Travels more slowly 0:05:53.440 --> 0:05:56.800 through water than through a vacuum, for example. So you 0:05:56.839 --> 0:05:59.839 take that constant of lights the speed of light in 0:05:59.880 --> 0:06:03.120 a vacuum, and you square it, so a number that's 0:06:03.120 --> 0:06:08.720 already huge gets huger. That huge number, by the way, 0:06:08.760 --> 0:06:13.400 in case you're wondering, is two hundred fifty eight meters 0:06:13.440 --> 0:06:17.120 per second. Squaring that you get eight point nine nine 0:06:17.160 --> 0:06:19.960 times ten to the sixteen power. It's a big number. 0:06:21.600 --> 0:06:24.160 So what that tells you if you look at that equation, 0:06:24.279 --> 0:06:26.279 what that tells you is that a very tiny amount 0:06:26.320 --> 0:06:30.400 of mass is equivalent to an enormous amount of energy, 0:06:31.560 --> 0:06:34.240 and vice versa, an enormous amount of energy is equivalent 0:06:34.240 --> 0:06:36.920 to a teeny tiny little bit of mass. So if 0:06:36.920 --> 0:06:41.480 you were to have a physical process in which you 0:06:41.520 --> 0:06:46.680 start with an atom and you split that atom and 0:06:46.800 --> 0:06:51.960 the two components of that split atom collectively have less 0:06:52.080 --> 0:06:58.280 mass than the original atom. You can't destroy or create 0:06:58.440 --> 0:07:00.560 energy or mass, but you can convert one to the other. 0:07:00.600 --> 0:07:04.400 That mask gets converted into energy, essentially kinetic energy, which 0:07:04.400 --> 0:07:06.640 gets convered into heat, and then you get a whole 0:07:06.680 --> 0:07:09.400 bunch of heat from it. Yeah, that's what Einstein had said. 0:07:09.400 --> 0:07:11.920 He says, this is this is the way the universe works. 0:07:12.160 --> 0:07:15.360 Energy and mass ultimately the same thing. And then there 0:07:15.400 --> 0:07:19.000 were if I recall, there were three broad historical reactions. 0:07:19.080 --> 0:07:24.760 Some people said nah, some people said maybe a lot 0:07:24.760 --> 0:07:29.080 of people went oh, yeah, exactly. Yeah, And and so 0:07:29.200 --> 0:07:31.960 this really uh, you know, we're gonna be talking about 0:07:32.000 --> 0:07:36.760 a lot about two different types of scientists. Theoretical scientists 0:07:36.840 --> 0:07:41.360 not they're not theoretical, they work in the realm of theory, 0:07:41.840 --> 0:07:46.280 and experimental scientists who take theory apply experiments to test 0:07:46.320 --> 0:07:50.280 those theories and then find out if the results either 0:07:50.360 --> 0:07:54.880 bear the theorial or it needs to be tweaked or whatever. Right, So, uh. 0:07:54.960 --> 0:08:00.600 In nineteen eleven we get another important development by discovery 0:08:00.640 --> 0:08:04.720 by the fellow named Ernest Rutherford. Now, Rutherford proposes a 0:08:04.760 --> 0:08:07.320 model of the atom in which you have a nucleus 0:08:07.360 --> 0:08:12.680 of positive particles which are dubbed protons, and they're orbited 0:08:12.720 --> 0:08:17.480 by negatively charged particles dubbed electrons. That's the Rutherford model 0:08:17.640 --> 0:08:20.840 of the atom. And it's the simplest version question. Yes, 0:08:20.960 --> 0:08:23.560 just just for you and the audience. I'm sure a 0:08:23.640 --> 0:08:25.680 lot of people have wondered this when they were learning this. 0:08:25.920 --> 0:08:29.280 When I can go with no trons, no tron's I mean, 0:08:29.320 --> 0:08:32.000 this sounds so much cooler because he was pro it's 0:08:32.000 --> 0:08:37.080 a positive thing. Well, they're like protons, electrons, protons, no trons. Oh, 0:08:37.120 --> 0:08:39.880 I got you. But being being negative, those would be 0:08:39.920 --> 0:08:43.960 the no trons. Well, because electrons are the agent through 0:08:44.000 --> 0:08:46.920 which electricity is you know, it's a matter of priority 0:08:47.000 --> 0:08:49.640 and that transcends a matter of marketing. But I'm saying 0:08:49.679 --> 0:08:51.640 we could even go back to the fact that Benjamin 0:08:51.679 --> 0:08:54.760 Franklin was convinced that current means that that's the movement 0:08:54.760 --> 0:08:57.520 of positively charged particles from one point to the other, 0:08:57.520 --> 0:08:59.679 which is why current flows in the opposite direction of 0:08:59.679 --> 0:09:03.400 actual electricity, which, by the way, drives me crazy. You've 0:09:03.400 --> 0:09:05.480 talked about it before, and which, by the way, I 0:09:05.480 --> 0:09:07.559 think we could cut to the end of the show 0:09:07.600 --> 0:09:11.920 because this means clearly that nuclear weapons are should be 0:09:11.960 --> 0:09:14.040 the blame for those should be laid at the at 0:09:14.040 --> 0:09:18.160 the field of Benjamin Franklin, like so many things. Bad guy. 0:09:18.400 --> 0:09:21.760 But anyway, Yeah, so Ernest Rutherford, So he discovers this, 0:09:21.840 --> 0:09:25.640 He creates this model, and then Neil's Bore, another important physicist. 0:09:25.840 --> 0:09:28.960 He refines that model. He starts to concentrate on the 0:09:29.040 --> 0:09:32.160 quantum behavior of electrons, and that's where we get the 0:09:32.240 --> 0:09:36.280 Bore model of Adams. And then I'm going to skip 0:09:36.320 --> 0:09:41.560 ahead to nineteen nineteen, and that's when Rutherford transmutes nitrogen 0:09:41.800 --> 0:09:45.439 into oxygen. This is something that alchemists had been attempting 0:09:45.480 --> 0:09:48.640 to do for centuries, although their form of transportation was 0:09:48.679 --> 0:09:51.480 more about lead into gold. Sure, sure, or the Philosopher's 0:09:51.480 --> 0:09:55.120 stone or whatever. But this is an actual transmutation. This 0:09:55.240 --> 0:09:59.000 is a point where Rutherford uh crosses. I don't want 0:09:59.040 --> 0:10:01.920 to say it as though he's like doing something bad, 0:10:01.960 --> 0:10:04.720 but where he where he goes from just a theory 0:10:04.880 --> 0:10:08.559 to the application the way we're talking about demonstrating it 0:10:08.840 --> 0:10:12.600 in the real world. And uh, this triggers even more 0:10:12.679 --> 0:10:16.080 changes in our timeline. Right. So the way he does 0:10:16.120 --> 0:10:20.560 this is he takes some nitrogen atoms and he bombards 0:10:20.600 --> 0:10:24.640 them with something called alpha particles and alpha particles essentially, 0:10:25.040 --> 0:10:28.079 although he didn't know this yet, an alpha particle is 0:10:28.160 --> 0:10:33.440 essentially to protons and two neutrons, also known as a 0:10:33.559 --> 0:10:38.280 heli helium nucleus. So if you use a helium nucleus, 0:10:38.320 --> 0:10:40.880 if you strip away the electrons, what you're left with 0:10:41.000 --> 0:10:44.840 is essentially an alpha particle. And he bobards these nitrogen 0:10:45.120 --> 0:10:47.959 adoms with that. That's what converts it over into oxygen. 0:10:49.040 --> 0:10:52.400 So then we skip ahead by a couple of decades. 0:10:53.320 --> 0:10:57.880 Are well a little more than a decade to two. Yes, 0:10:58.160 --> 0:11:01.600 this is when James Chadwick, was one of Rutherford's colleagues, 0:11:01.960 --> 0:11:04.400 discovers the nucleus of an atom can by the way, 0:11:05.000 --> 0:11:09.200 two big year in physics. Yeah, so he discovers that 0:11:09.240 --> 0:11:12.199 the nucleus of an atom can also contain particles that 0:11:12.320 --> 0:11:15.280 have no charge at all, hanging out. They're just they're 0:11:15.600 --> 0:11:17.920 they're they're kind of like that roommate I used to have, 0:11:18.080 --> 0:11:21.280 who you know. I felt like, come on, dude, just 0:11:21.280 --> 0:11:23.640 just pay your part of the utilities already. Come on. 0:11:23.800 --> 0:11:28.960 I'm sorry. I wasn't gonna be so yeah, these are 0:11:29.080 --> 0:11:32.800 these are neutral. That's that's the neutrons. And by this 0:11:32.840 --> 0:11:36.400 time there was an understanding now that the atoms typically 0:11:36.400 --> 0:11:39.840 consisted of protons and neutrons, and the nucleus and orbited 0:11:39.840 --> 0:11:42.040 by a number of electrons that were equal to the 0:11:42.160 --> 0:11:45.840 number of protons, and that's what balances out the charge. 0:11:46.440 --> 0:11:51.040 There's a but oh, let's infommercial it. But wait, there's more. 0:11:51.080 --> 0:11:53.400 There is more. Two things that you can you can 0:11:54.040 --> 0:11:56.800 talk about, one which is really important in nuclear physics, 0:11:56.840 --> 0:11:59.080 and one which is not going to really play a part. 0:11:59.400 --> 0:12:01.199 One of the that being that if you have an 0:12:01.240 --> 0:12:05.360 atom that has an excess or of electrons or too 0:12:05.400 --> 0:12:08.800 few electrons, it's an UH. It's an ion of that 0:12:08.840 --> 0:12:12.560 particular atom. But you can also have a different number 0:12:12.600 --> 0:12:16.720 of neutrons from the protons. You can have a variety 0:12:16.800 --> 0:12:19.880 of them, and we call these different varieties of these 0:12:19.920 --> 0:12:24.480 various atoms isotopes. So an isotope of an atom is 0:12:24.960 --> 0:12:27.400 UH is a version of that atom that has a 0:12:27.440 --> 0:12:31.040 specific number of neutrons. So that's important to remember now. 0:12:31.080 --> 0:12:36.360 At the time when Chadwick made this discovery, hydrogen was 0:12:36.640 --> 0:12:41.200 the the the lightest, the least massive of all the 0:12:41.240 --> 0:12:44.520 elements at one and the heaviest or the one with 0:12:44.600 --> 0:12:47.800 the most mass, was uranium at ninety two. That number 0:12:47.880 --> 0:12:50.720 refers to the number of protons in the atom, not 0:12:50.840 --> 0:12:54.560 the number of neutrons. So chemists had discovered that the 0:12:54.600 --> 0:12:57.480 atoms of the of the same elements sometimes had different weights. 0:12:57.520 --> 0:13:00.240 This is what led to the discovery of isotopes. So 0:13:00.280 --> 0:13:03.959 they'd say, oh, well, here's a uranium atom, but we've 0:13:03.960 --> 0:13:07.520 got this other uranium atom and they they're chemically identical. 0:13:08.040 --> 0:13:11.480 They're exactly the same chemically, but this other one is 0:13:11.520 --> 0:13:14.840 a little heavier than this one. So what is what? 0:13:15.040 --> 0:13:17.920 That doesn't make sense, and that's where they discovered isotopes. 0:13:18.200 --> 0:13:21.720 So uranium has three isotopes. All of them have ninety 0:13:21.720 --> 0:13:23.920 two protons and ninety two electrons, because if they didn't, 0:13:23.960 --> 0:13:26.760 it wouldn't be uranium. But it does have a different 0:13:26.800 --> 0:13:29.200 number of neutrons. So you've got uranium two three eight. 0:13:30.240 --> 0:13:33.440 That's the most common form of uranium found in nature. 0:13:34.000 --> 0:13:36.040 U It has a hundred forty six neutrons in the 0:13:36.120 --> 0:13:41.080 nucleus and it's nine. It makes all natural uranium. So 0:13:41.400 --> 0:13:44.400 when you when you go uranium hunting, odds are you 0:13:44.440 --> 0:13:46.680 going to find? You two thirty eight. Then you have 0:13:46.800 --> 0:13:49.760 uranium two thirty five which has a hundred forty three neutrons, 0:13:50.120 --> 0:13:53.880 and uranium two thirty four, which has at two neutrons. 0:13:54.640 --> 0:13:59.320 And you two thirty five will become incredibly important in 0:13:59.440 --> 0:14:02.920 this DISCUSSI and you two thirty four is one of 0:14:02.920 --> 0:14:09.840 the decay products. Right. So, also in ninety two going 0:14:09.920 --> 0:14:12.920 on at the same time, you had physicists J. D. 0:14:13.120 --> 0:14:17.000 Crocroft and E. T. S. Walton split a lithium atom 0:14:17.040 --> 0:14:21.480 into two helium nuclei. Uh, the the protons and neutrons 0:14:21.480 --> 0:14:24.800 I was talking about, by bombarding the lithium with protons 0:14:24.880 --> 0:14:28.800 using a particle accelerator. And this is the first example 0:14:28.840 --> 0:14:32.760 of someone splitting the atom the very first time. Yeah, 0:14:32.920 --> 0:14:36.040 it is. In my opinion, this is up there with 0:14:36.600 --> 0:14:40.160 the first human footfall on the move. Ye. This fundamentally 0:14:40.840 --> 0:14:45.160 changes everything, and it's strange that we don't hear more 0:14:45.160 --> 0:14:47.760 people talk about it. Yeah, a lot of people will 0:14:48.160 --> 0:14:52.520 talk about the early work in nuclear fission, which we 0:14:52.520 --> 0:14:56.680 will get to, which happened in a place that precipitated 0:14:56.760 --> 0:15:01.240 the need from men on projects. So in California two 0:15:01.600 --> 0:15:04.680 same time as everything else, you had a group with 0:15:04.960 --> 0:15:08.400 Ernest oh Lawrence, who will be incredibly important in this conversation. 0:15:08.880 --> 0:15:14.320 Stanley Livingston and Milton White who operated the first cyclotron 0:15:14.440 --> 0:15:17.880 on the Berkeley campus of the University of California, and 0:15:18.280 --> 0:15:20.920 Lawrence would end up playing an instrumental role in the 0:15:20.920 --> 0:15:26.840 Manhattan Project. Yeah. No, for everyone who's wondering a cyclotron, 0:15:27.120 --> 0:15:30.880 it was a particle accelerator, right right. It was this 0:15:30.960 --> 0:15:34.200 is the era where we start getting the earliest particle accelerators. 0:15:34.320 --> 0:15:38.160 The Vandergraf would build one as well, in a different style. Uh. 0:15:38.200 --> 0:15:43.120 And Lawrence was was working on this early and not 0:15:43.360 --> 0:15:47.400 with the goal of nuclear fission necessarily. It was part 0:15:47.480 --> 0:15:51.360 of particle physics to understand more about the fundamental particles 0:15:51.360 --> 0:15:55.200 that make up all the stuff around us. Uh. And 0:15:55.400 --> 0:15:58.640 it ultimately would end up being used to help create 0:15:59.160 --> 0:16:03.560 the material real for nuclear weapons, but at the time 0:16:03.600 --> 0:16:08.160 no one had any concept of doing that. Three. There 0:16:08.200 --> 0:16:10.240 were some early attempts to find a reliable way to 0:16:10.320 --> 0:16:15.040 split atoms, but they're largely unsuccessful or very inefficient. They 0:16:15.080 --> 0:16:18.360 require huge amounts of power, and I'll tell you why. 0:16:18.960 --> 0:16:22.680 Most of them used protons fired at an atomic nucleus. 0:16:23.280 --> 0:16:25.920 So here's the thing. Protons have a positive charge. Correct 0:16:26.640 --> 0:16:29.920 atomic nucleus also has a positive charge because it's only 0:16:29.960 --> 0:16:32.880 made up of protons and neutrons, so we have positive 0:16:32.880 --> 0:16:35.520 and positive So what happens if you put two ends, 0:16:35.520 --> 0:16:40.080 like two northern ends of two different magnets together hate 0:16:40.120 --> 0:16:43.160 each other. Yeah, they do. It's uh, you know a 0:16:43.160 --> 0:16:46.280 lot like me and Josh Clark, we just despite the 0:16:46.320 --> 0:16:47.840 fact we sit right next to each other, there's just 0:16:47.880 --> 0:16:53.640 this repulsion. It's the other one. It's kind of amazing, Like, 0:16:53.680 --> 0:16:56.320 you know, like if I start walking towards Josh's chair 0:16:56.400 --> 0:16:59.200 just rolls the other way. Now Josh and I get 0:16:59.200 --> 0:17:02.000 along just time. Obviously he was just recently on the 0:17:02.480 --> 0:17:05.480 tech stuff, so um. But yeah, it was really hard 0:17:05.520 --> 0:17:07.639 to get a direct hit on a nucleus because of 0:17:07.680 --> 0:17:11.560 this these light charges repelling one another. In fact, there 0:17:11.560 --> 0:17:13.720 were some estimates that said that it only happened one 0:17:14.200 --> 0:17:19.359 every one million tries non efficient way to split at him. 0:17:19.920 --> 0:17:23.760 So while people were starting to think there might be 0:17:23.880 --> 0:17:27.439 a way of getting some energy from this, like to 0:17:27.520 --> 0:17:30.000 use this as a means of generating power or perhaps 0:17:30.200 --> 0:17:34.800 even creating a weapon down the line, the efficiency was 0:17:34.880 --> 0:17:37.160 so low that it didn't seem like it was going 0:17:37.200 --> 0:17:42.680 to be uh A viable exactly, Like it's a good 0:17:42.720 --> 0:17:48.240 proof of concept. Yeah, So Albert Einstein, niels Bore, and 0:17:48.320 --> 0:17:50.480 Rutherford all felt that the process would be great for 0:17:50.480 --> 0:17:53.800 getting a better understanding of nuclear physics, but would remain 0:17:53.840 --> 0:17:57.960 impractical for pretty much anything else. Now, Rutherford actually described 0:17:58.000 --> 0:18:02.399 the idea of harnessing nuclear inner g as moonshine. That 0:18:02.520 --> 0:18:06.800 was what he called it. Einstein his version was saying, 0:18:06.880 --> 0:18:10.680 it's like the ability to get a proton to to 0:18:11.160 --> 0:18:14.160 collide with the nucleus would be akin to walking into 0:18:14.160 --> 0:18:17.679 an enormous room that's pitch black and shooting at a 0:18:17.720 --> 0:18:21.120 couple of birds flying around randomly through the right. Yeah, 0:18:21.440 --> 0:18:23.679 that was his his comparison. And then no way to 0:18:23.720 --> 0:18:26.879 make it not an accident, right, and heels Bore said, 0:18:27.160 --> 0:18:29.240 it's pretty much a long shot unless we figure out 0:18:29.280 --> 0:18:32.680 something else. And then you had another fellow, a Hungarian 0:18:32.720 --> 0:18:36.919 physicist who was living in the United States, Leo sciss Lard, 0:18:38.000 --> 0:18:41.440 and sciss Lard hypothesized that if you use something else, 0:18:41.520 --> 0:18:44.359 not protons, what have you used a beam of neutrons 0:18:45.600 --> 0:18:48.560 aimed at an atom, Because neutrons have no charge, so 0:18:49.960 --> 0:18:52.240 there's no repulstion there. Yeah, The only thing is that 0:18:52.359 --> 0:18:57.280 how do you shoot a non charged particle, Because if 0:18:57.320 --> 0:18:59.760 you're using protons, then all you can do, all you 0:18:59.800 --> 0:19:01.840 have to do is created a positive charge to repel 0:19:01.920 --> 0:19:04.680 it or a negative charge to attract it and move 0:19:04.680 --> 0:19:07.520 it that way, but a neutral one is a little trickier. 0:19:08.119 --> 0:19:11.040 Um But he thought if you could do this, and 0:19:11.160 --> 0:19:13.920 if the atom was large enough where it had its 0:19:13.920 --> 0:19:18.400 own neutrons, sometimes when that atom splits up, it might 0:19:18.440 --> 0:19:20.720 give off neutrons too. And if it gives off neutrons 0:19:20.720 --> 0:19:26.000 with enough energy and you have enough atoms there, those 0:19:26.000 --> 0:19:29.680 neutrons could collide with other atoms, which could cause them 0:19:30.000 --> 0:19:33.159 to break apart, and those neutrons could go out and 0:19:33.240 --> 0:19:36.520 hit other atoms, and each time you would be multiplying 0:19:36.520 --> 0:19:38.399 this effect. As long as you had more than one 0:19:38.480 --> 0:19:41.200 neutron being given off and as long as those were 0:19:41.200 --> 0:19:45.240 colliding with some other atoms, this trend would continue until 0:19:45.240 --> 0:19:47.760 you were out of stuff or the neutrons or therere 0:19:47.760 --> 0:19:49.960 just weren't enough atoms for the neutrons to make contact, 0:19:50.520 --> 0:19:52.879 and you would get a nuclear chain reaction which you 0:19:52.920 --> 0:19:55.399 could use to either power or a city or blow 0:19:55.440 --> 0:19:58.760 one up. Yes, yes, at that point they you know, 0:19:59.000 --> 0:20:03.680 the next question and becomes like, well, yes, at that point, 0:20:03.760 --> 0:20:10.239 the next question becomes a matter of control, because you know, 0:20:10.280 --> 0:20:15.440 it's all well and good from an academic perspective to say, oh, guys, 0:20:15.520 --> 0:20:18.280 look at this neat thing that we think we can do. 0:20:18.720 --> 0:20:20.840 And then you know, for someone to say, okay, well 0:20:20.920 --> 0:20:23.400 let's let's try it. Let's get the rubber on the road, 0:20:23.560 --> 0:20:25.680 and then what do you think is going to happen? 0:20:25.720 --> 0:20:29.760 And they say, well, one or two things. It's either 0:20:29.840 --> 0:20:34.199 going to power the city or blow it up. But 0:20:34.400 --> 0:20:37.560 we're pretty confident it's going to be one of those two. 0:20:37.600 --> 0:20:39.360 So the next question is like, how do you make 0:20:39.440 --> 0:20:43.399 this use right? And and for Leo, I'm gonna call 0:20:43.560 --> 0:20:45.199 Leo because I'm just gonna Putcher his last name off 0:20:45.320 --> 0:20:49.919 otherwise the Hungarian physicist. Uh. For Leo, the problem was 0:20:49.960 --> 0:20:52.359 that when he was first trying this out, he was 0:20:52.440 --> 0:20:56.600 using lighter atoms and he couldn't get these sustained reactions, 0:20:56.600 --> 0:20:58.720 so he kind of he kind of thought, well, I 0:20:58.720 --> 0:21:00.840 guess that's a bust. It's like a good idea, but 0:21:00.840 --> 0:21:04.040 it's not working. So so so there it became an 0:21:04.080 --> 0:21:06.639 academic question for a while because there was, they weren't. 0:21:06.680 --> 0:21:09.520 He wasn't using the heavier atoms, which would have created 0:21:09.560 --> 0:21:12.520 a sustainable reaction, would have been dense enough to have 0:21:12.960 --> 0:21:15.960 that impact. They don't decay in the same way that 0:21:16.000 --> 0:21:18.480 other other ones might just take on the neutron, they 0:21:18.520 --> 0:21:21.959 wouldn't split apart. In other words, we'll be back with 0:21:21.960 --> 0:21:24.600 more of this classic episode of tech stuff after this 0:21:24.720 --> 0:21:36.119 quick break. So moving on with four, we get another 0:21:36.160 --> 0:21:39.800 fellow who becomes very important in Manhattan Project, Enrico Fermi, 0:21:40.560 --> 0:21:44.440 an Italian physicist. He begins to use neutrons to bobard atoms, 0:21:44.480 --> 0:21:47.120 and he figured the uncharged particles wouldn't meet that same 0:21:47.119 --> 0:21:50.880 resistance as protons, just as Leo had. He was right. 0:21:51.600 --> 0:21:54.960 He bombarded sixty three different stable elements with neutrons and 0:21:55.000 --> 0:21:59.080 created thirty seven new radioactive atoms. And he also found 0:21:59.080 --> 0:22:02.080 out that if he used urban and hydrogen, he could 0:22:02.119 --> 0:22:04.480 actually slow the movement of the neutrons a little bit, 0:22:05.440 --> 0:22:07.680 and that would actually increase the chances of a nucleus 0:22:07.760 --> 0:22:11.879 accepting a new neutron. So you wanted to fire the 0:22:11.880 --> 0:22:15.159 neutrons fast, but not too fast. You had you had 0:22:15.200 --> 0:22:19.240 to control that. So he then bombarded uranium with neutrons 0:22:19.240 --> 0:22:23.520 had created something, but he had no idea what it was. 0:22:24.440 --> 0:22:26.520 In fact, no one was really sure at the time. 0:22:26.520 --> 0:22:28.760 There was a lot of disagreement in the scientific community 0:22:28.800 --> 0:22:32.080 about whatever for Me had made because it was new, 0:22:32.640 --> 0:22:35.880 and because it was new, they didn't know, right. So, Yeah, 0:22:35.920 --> 0:22:38.359 so they were wondering if it was transuranic, as in 0:22:38.480 --> 0:22:42.600 a man made element that would not be found in nature, 0:22:43.400 --> 0:22:45.240 or if for Me had somehow managed to split up 0:22:45.359 --> 0:22:48.919 uranium so that behave like lighter elements, because some of 0:22:48.920 --> 0:22:52.320 the stuff that was left over it seemed really similar 0:22:52.320 --> 0:22:56.200 to lighter elements on the elemental table, But how could 0:22:56.200 --> 0:23:01.000 that be magic? Yeah, and it's fine because he had 0:23:01.040 --> 0:23:05.240 actually achieved nuclear fission but did not know it. He 0:23:05.280 --> 0:23:08.400 didn't he didn't understand it enough to know that that's 0:23:08.440 --> 0:23:10.919 what had happened at the time. And that takes us 0:23:10.960 --> 0:23:15.320 to thirty eight. And this is the event that really 0:23:16.080 --> 0:23:19.439 creates the need for the Manhattan Project because it takes 0:23:19.440 --> 0:23:23.760 place in Berlin. Now, nineteen thirty eight. In Berlin, it 0:23:23.880 --> 0:23:27.280 was already a very tumultuous time in Europe, right. World 0:23:27.320 --> 0:23:30.560 War two had not yet begun, but Germany had started 0:23:30.600 --> 0:23:36.480 to really cause huge problems, including UH cracking down on 0:23:36.560 --> 0:23:41.359 the Jewish population already UH, and it was you know, 0:23:41.520 --> 0:23:46.560 the whole Germany Austrian alliance was was an issue. And 0:23:46.600 --> 0:23:51.720 then there were rumblings about Germany possibly invading other countries. 0:23:52.520 --> 0:23:55.360 And then this was also spreading to you know, Italy 0:23:55.400 --> 0:24:01.080 as well. Yes, Italy was also invading African nations at 0:24:01.080 --> 0:24:04.240 the time. So this was really a tumultuous period. So 0:24:04.280 --> 0:24:08.399 in Berlin, UH, Germany was a place where there where 0:24:08.480 --> 0:24:13.120 particle physics, theoretical physics had really blossomed at the end 0:24:13.200 --> 0:24:17.040 of the nineteenth century beginning of the twentieth century, and 0:24:17.720 --> 0:24:21.080 you had a collection of scientists who all were just 0:24:21.680 --> 0:24:26.960 interested in furthering our understanding of the universe. They just 0:24:27.040 --> 0:24:29.560 happened to be in a place where that understanding was 0:24:29.560 --> 0:24:33.840 going to be UH tilted toward the ends of the 0:24:33.880 --> 0:24:40.360 German government. So radiochemists Auto Han and Fritz Strassman, we're 0:24:40.440 --> 0:24:43.320 using firms method of bombarding atoms with neutrons, and they 0:24:43.359 --> 0:24:48.600 found that uranium nuclei, unlike other nuclei, didn't just absorb 0:24:48.680 --> 0:24:51.719 the neutrons. They broke apart into two more or less 0:24:51.800 --> 0:24:56.960 equal pieces. They became fragments of uranium and radioactive barrium isotopes, 0:24:57.280 --> 0:24:59.960