TechStuff Classic: The Manhattan Project Part One

In this episode, Ben Bowlin joins the show to talk about the scientific and political landscape that made the Manhattan Project possible. What was Einstein's role? Who first discovered nuclear fission?

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Episode Transcript

Speaker 1 (00:04):
Welcome to tech Stuff, a production from I Heart Radio.
Hey there, and welcome to tech Stuff. I am your
host job in Strickland. I'm an executive producer with I
Heart Radio and how the tech are here. It's time
for a tech Stuff classic episode. This episode originally published

(00:24):
July fifteen. It is titled The Manhattan Project Part One,
So I bet you can guess what next week's classic
episode is. This episode had been bolan of stuff they
don't want you to know, and Ridiculous History joined the
episode to talk about the Manhattan Project. We really get
into the physics in this one. Hope you enjoy. I

(00:47):
don't want to disparage the gravity of what we're doing
anything less than a few tangents or puns in this story,
because this is a fascinating story. It's a fascinating story,
and and you can't get around the fact that the
end of the story is massively tragic, right like, like,
there's there's a ton of things that we can talk about,

(01:09):
and what we are talking about is the Manhattan Project.
And I'm gonna go ahead and let you guys know,
this sucker is going to be a two parter because
in order to cover the Manhattan Project. You have to
have an understanding of what was going on in physics
leading up to the beginning of the project, which will
be this episode, and then there's another episode that will
be all about the actual developments of the project itself.

(01:32):
And this is complicated for multiple reasons. One, nuclear physics
not straightforward as it turns out. Yeah, actually lots of
pressure because of the implosion technique, but we'll get into
that in episode two. Also politics, a lot of politics.
I mean, obviously, the Manhattan Project was formed as a
result of World War Two. If World War Two had

(01:54):
not been happening, the Manhattan Project probably would not have
been formed, and nuclear power may have either been pushed
back by quite a bit or someone else would have
ended up developing it ahead of the United States. So
both of those things. Science and politics by themselves are complex,
and when you combine the two and you try to

(02:14):
make science work within the realm of a political structure,
it gets messy. Yeah, and not not in like a
cool I got my hair cut at a nice salon,
Look at me. Messy. No, not like rolled out of bed.
Oh this didn't take me any time at all, right,
messy as in uh is a massive loss of blood

(02:35):
and treasure. I think we're looking at the equivalent of
when it got rolling thirty billion dollars you you know,
in money. All yeah, today's money. It all depends upon
the well, it really depends upon how you define the
scope of the project. Because that's something else that's kind
of confusing, because you hear Manhattan Project and you think, okay, uh,

(02:57):
Manhattan Project, that's the one that took place in oak Ridge, Tennessee, Hanford, Washington,
Los Alamos, New Mexico. Makes sense. We will explain all
of that as we go through. So in case you
weren't aware, the Manhattan Project was the code named the
United States government gave to the the effort to design
and build an atomic bomb for use in World War two.

(03:22):
And in order for us to talk about we have
to go back way before World War two. In fact,
we have to go back before World War One. Yes, yeah,
we have to go all the way back to the
I guess the end of the nineteenth century, that is correct,
late nineteenth century. Uh, there was a fella by the
name of Henrie Beccarell alright, who had made an interesting

(03:44):
observation observing that some material when placed against some plates
would create a negative image. And he had assumed that
this material was phosphorescent, that it absorbed light and then
given off some form of ray to create this image,

(04:05):
but later determined that he was mistaken, that there was
no need for the sunlight. The stuff was giving off
the rays by itself. And then you had the Curies
coming along, who who went on to study this themselves.
Marie Cury coined the term radioactive radioactive with the word

(04:27):
ray in it. And so at this point there was
an understanding that certain elements had a type of energy
they could give off spontaneously, spontaneous radiation. And that is
the beginning the nub, that the kernel that forms the

(04:47):
the very center of the Manhattan Project's purpose. So building
on that we then have there's a guy in Nive.
He had a little theory. It was a special theory,
I mean relatively special man. Yes, yes, And that that
man you may know today through countless Internet memes Albert Einstein. Yes, yes,

(05:11):
Albert Einstein, al to his friends, was a brilliant physicist, obviously,
and it was all the way back in n when
Einstein proposed the special theory of relativity, which, among many
other things, positive that energy and matter are pretty much interchangeable.
And this is where the the famous equation E equals

(05:34):
MC squared comes from. The E means energy, the M
means mass. The C squared C stands for the constant
of the speed of light through a vacuum. Keeping in
mind that light actually can travel at different speeds depending
upon the medium through which it travels. Travels more slowly
through water than through a vacuum, for example. So you

(05:56):
take that constant of lights the speed of light in
a vacuum, and you square it, so a number that's
already huge gets huger. That huge number, by the way,
in case you're wondering, is two hundred fifty eight meters
per second. Squaring that you get eight point nine nine

(06:17):
times ten to the sixteen power. It's a big number.
So what that tells you if you look at that equation,
what that tells you is that a very tiny amount
of mass is equivalent to an enormous amount of energy,
and vice versa, an enormous amount of energy is equivalent
to a teeny tiny little bit of mass. So if
you were to have a physical process in which you

(06:41):
start with an atom and you split that atom and
the two components of that split atom collectively have less
mass than the original atom. You can't destroy or create
energy or mass, but you can convert one to the other.
That mask gets converted into energy, essentially kinetic energy, which

(07:04):
gets convered into heat, and then you get a whole
bunch of heat from it. Yeah, that's what Einstein had said.
He says, this is this is the way the universe works.
Energy and mass ultimately the same thing. And then there
were if I recall, there were three broad historical reactions.
Some people said nah, some people said maybe a lot

(07:24):
of people went oh, yeah, exactly. Yeah, And and so
this really uh, you know, we're gonna be talking about
a lot about two different types of scientists. Theoretical scientists
not they're not theoretical, they work in the realm of theory,
and experimental scientists who take theory apply experiments to test

(07:46):
those theories and then find out if the results either
bear the theorial or it needs to be tweaked or whatever. Right, So, uh.
In nineteen eleven we get another important development by discovery
by the fellow named Ernest Rutherford. Now, Rutherford proposes a
model of the atom in which you have a nucleus

(08:07):
of positive particles which are dubbed protons, and they're orbited
by negatively charged particles dubbed electrons. That's the Rutherford model
of the atom. And it's the simplest version question. Yes,
just just for you and the audience. I'm sure a
lot of people have wondered this when they were learning this.
When I can go with no trons, no tron's I mean,

(08:29):
this sounds so much cooler because he was pro it's
a positive thing. Well, they're like protons, electrons, protons, no trons. Oh,
I got you. But being being negative, those would be
the no trons. Well, because electrons are the agent through
which electricity is you know, it's a matter of priority
and that transcends a matter of marketing. But I'm saying

(08:49):
we could even go back to the fact that Benjamin
Franklin was convinced that current means that that's the movement
of positively charged particles from one point to the other,
which is why current flows in the opposite direction of
actual electricity, which, by the way, drives me crazy. You've
talked about it before, and which, by the way, I
think we could cut to the end of the show
because this means clearly that nuclear weapons are should be

(09:11):
the blame for those should be laid at the at
the field of Benjamin Franklin, like so many things. Bad guy.
But anyway, Yeah, so Ernest Rutherford, So he discovers this,
He creates this model, and then Neil's Bore, another important physicist.
He refines that model. He starts to concentrate on the
quantum behavior of electrons, and that's where we get the

(09:32):
Bore model of Adams. And then I'm going to skip
ahead to nineteen nineteen, and that's when Rutherford transmutes nitrogen
into oxygen. This is something that alchemists had been attempting
to do for centuries, although their form of transportation was
more about lead into gold. Sure, sure, or the Philosopher's
stone or whatever. But this is an actual transmutation. This

(09:55):
is a point where Rutherford uh crosses. I don't want
to say it as though he's like doing something bad,
but where he where he goes from just a theory
to the application the way we're talking about demonstrating it
in the real world. And uh, this triggers even more
changes in our timeline. Right. So the way he does

(10:16):
this is he takes some nitrogen atoms and he bombards
them with something called alpha particles and alpha particles essentially,
although he didn't know this yet, an alpha particle is
essentially to protons and two neutrons, also known as a
heli helium nucleus. So if you use a helium nucleus,

(10:38):
if you strip away the electrons, what you're left with
is essentially an alpha particle. And he bobards these nitrogen
adoms with that. That's what converts it over into oxygen.
So then we skip ahead by a couple of decades.
Are well a little more than a decade to two. Yes,
this is when James Chadwick, was one of Rutherford's colleagues,

(11:01):
discovers the nucleus of an atom can by the way,
two big year in physics. Yeah, so he discovers that
the nucleus of an atom can also contain particles that
have no charge at all, hanging out. They're just they're
they're they're kind of like that roommate I used to have,
who you know. I felt like, come on, dude, just
just pay your part of the utilities already. Come on.

(11:23):
I'm sorry. I wasn't gonna be so yeah, these are
these are neutral. That's that's the neutrons. And by this
time there was an understanding now that the atoms typically
consisted of protons and neutrons, and the nucleus and orbited
by a number of electrons that were equal to the
number of protons, and that's what balances out the charge.

(11:46):
There's a but oh, let's infommercial it. But wait, there's more.
There is more. Two things that you can you can
talk about, one which is really important in nuclear physics,
and one which is not going to really play a part.
One of the that being that if you have an
atom that has an excess or of electrons or too
few electrons, it's an UH. It's an ion of that

(12:08):
particular atom. But you can also have a different number
of neutrons from the protons. You can have a variety
of them, and we call these different varieties of these
various atoms isotopes. So an isotope of an atom is
UH is a version of that atom that has a
specific number of neutrons. So that's important to remember now.

(12:31):
At the time when Chadwick made this discovery, hydrogen was
the the the lightest, the least massive of all the
elements at one and the heaviest or the one with
the most mass, was uranium at ninety two. That number
refers to the number of protons in the atom, not
the number of neutrons. So chemists had discovered that the

(12:54):
atoms of the of the same elements sometimes had different weights.
This is what led to the discovery of isotopes. So
they'd say, oh, well, here's a uranium atom, but we've
got this other uranium atom and they they're chemically identical.
They're exactly the same chemically, but this other one is
a little heavier than this one. So what is what?

(13:15):
That doesn't make sense, and that's where they discovered isotopes.
So uranium has three isotopes. All of them have ninety
two protons and ninety two electrons, because if they didn't,
it wouldn't be uranium. But it does have a different
number of neutrons. So you've got uranium two three eight.
That's the most common form of uranium found in nature.
U It has a hundred forty six neutrons in the

(13:36):
nucleus and it's nine. It makes all natural uranium. So
when you when you go uranium hunting, odds are you
going to find? You two thirty eight. Then you have
uranium two thirty five which has a hundred forty three neutrons,
and uranium two thirty four, which has at two neutrons.
And you two thirty five will become incredibly important in

(13:59):
this DISCUSSI and you two thirty four is one of
the decay products. Right. So, also in ninety two going
on at the same time, you had physicists J. D.
Crocroft and E. T. S. Walton split a lithium atom
into two helium nuclei. Uh, the the protons and neutrons

(14:21):
I was talking about, by bombarding the lithium with protons
using a particle accelerator. And this is the first example
of someone splitting the atom the very first time. Yeah,
it is. In my opinion, this is up there with
the first human footfall on the move. Ye. This fundamentally
changes everything, and it's strange that we don't hear more

(14:45):
people talk about it. Yeah, a lot of people will
talk about the early work in nuclear fission, which we
will get to, which happened in a place that precipitated
the need from men on projects. So in California two
same time as everything else, you had a group with
Ernest oh Lawrence, who will be incredibly important in this conversation.

(15:08):
Stanley Livingston and Milton White who operated the first cyclotron
on the Berkeley campus of the University of California, and
Lawrence would end up playing an instrumental role in the
Manhattan Project. Yeah. No, for everyone who's wondering a cyclotron,
it was a particle accelerator, right right. It was this

(15:30):
is the era where we start getting the earliest particle accelerators.
The Vandergraf would build one as well, in a different style. Uh.
And Lawrence was was working on this early and not
with the goal of nuclear fission necessarily. It was part
of particle physics to understand more about the fundamental particles

(15:51):
that make up all the stuff around us. Uh. And
it ultimately would end up being used to help create
the material real for nuclear weapons, but at the time
no one had any concept of doing that. Three. There
were some early attempts to find a reliable way to
split atoms, but they're largely unsuccessful or very inefficient. They

(16:15):
require huge amounts of power, and I'll tell you why.
Most of them used protons fired at an atomic nucleus.
So here's the thing. Protons have a positive charge. Correct
atomic nucleus also has a positive charge because it's only
made up of protons and neutrons, so we have positive
and positive So what happens if you put two ends,

(16:35):
like two northern ends of two different magnets together hate
each other. Yeah, they do. It's uh, you know a
lot like me and Josh Clark, we just despite the
fact we sit right next to each other, there's just
this repulsion. It's the other one. It's kind of amazing, Like,
you know, like if I start walking towards Josh's chair

(16:56):
just rolls the other way. Now Josh and I get
along just time. Obviously he was just recently on the
tech stuff, so um. But yeah, it was really hard
to get a direct hit on a nucleus because of
this these light charges repelling one another. In fact, there
were some estimates that said that it only happened one
every one million tries non efficient way to split at him.

(17:19):
So while people were starting to think there might be
a way of getting some energy from this, like to
use this as a means of generating power or perhaps
even creating a weapon down the line, the efficiency was
so low that it didn't seem like it was going
to be uh A viable exactly, Like it's a good

(17:42):
proof of concept. Yeah, So Albert Einstein, niels Bore, and
Rutherford all felt that the process would be great for
getting a better understanding of nuclear physics, but would remain
impractical for pretty much anything else. Now, Rutherford actually described
the idea of harnessing nuclear inner g as moonshine. That
was what he called it. Einstein his version was saying,

(18:06):
it's like the ability to get a proton to to
collide with the nucleus would be akin to walking into
an enormous room that's pitch black and shooting at a
couple of birds flying around randomly through the right. Yeah,
that was his his comparison. And then no way to
make it not an accident, right, and heels Bore said,

(18:27):
it's pretty much a long shot unless we figure out
something else. And then you had another fellow, a Hungarian
physicist who was living in the United States, Leo sciss Lard,
and sciss Lard hypothesized that if you use something else,
not protons, what have you used a beam of neutrons
aimed at an atom, Because neutrons have no charge, so

(18:49):
there's no repulstion there. Yeah, The only thing is that
how do you shoot a non charged particle, Because if
you're using protons, then all you can do, all you
have to do is created a positive charge to repel
it or a negative charge to attract it and move
it that way, but a neutral one is a little trickier.
Um But he thought if you could do this, and

(19:11):
if the atom was large enough where it had its
own neutrons, sometimes when that atom splits up, it might
give off neutrons too. And if it gives off neutrons
with enough energy and you have enough atoms there, those
neutrons could collide with other atoms, which could cause them
to break apart, and those neutrons could go out and

(19:33):
hit other atoms, and each time you would be multiplying
this effect. As long as you had more than one
neutron being given off and as long as those were
colliding with some other atoms, this trend would continue until
you were out of stuff or the neutrons or therere
just weren't enough atoms for the neutrons to make contact,
and you would get a nuclear chain reaction which you
could use to either power or a city or blow

(19:55):
one up. Yes, yes, at that point they you know,
the next question and becomes like, well, yes, at that point,
the next question becomes a matter of control, because you know,
it's all well and good from an academic perspective to say, oh, guys,

(20:15):
look at this neat thing that we think we can do.
And then you know, for someone to say, okay, well
let's let's try it. Let's get the rubber on the road,
and then what do you think is going to happen?
And they say, well, one or two things. It's either
going to power the city or blow it up. But
we're pretty confident it's going to be one of those two.

(20:37):
So the next question is like, how do you make
this use right? And and for Leo, I'm gonna call
Leo because I'm just gonna Putcher his last name off
otherwise the Hungarian physicist. Uh. For Leo, the problem was
that when he was first trying this out, he was
using lighter atoms and he couldn't get these sustained reactions,
so he kind of he kind of thought, well, I

(20:58):
guess that's a bust. It's like a good idea, but
it's not working. So so so there it became an
academic question for a while because there was, they weren't.
He wasn't using the heavier atoms, which would have created
a sustainable reaction, would have been dense enough to have
that impact. They don't decay in the same way that
other other ones might just take on the neutron, they
wouldn't split apart. In other words, we'll be back with

(21:21):
more of this classic episode of tech stuff after this
quick break. So moving on with four, we get another
fellow who becomes very important in Manhattan Project, Enrico Fermi,
an Italian physicist. He begins to use neutrons to bobard atoms,

(21:44):
and he figured the uncharged particles wouldn't meet that same
resistance as protons, just as Leo had. He was right.
He bombarded sixty three different stable elements with neutrons and
created thirty seven new radioactive atoms. And he also found
out that if he used urban and hydrogen, he could
actually slow the movement of the neutrons a little bit,

(22:05):
and that would actually increase the chances of a nucleus
accepting a new neutron. So you wanted to fire the
neutrons fast, but not too fast. You had you had
to control that. So he then bombarded uranium with neutrons
had created something, but he had no idea what it was.
In fact, no one was really sure at the time.

(22:26):
There was a lot of disagreement in the scientific community
about whatever for Me had made because it was new,
and because it was new, they didn't know, right. So, Yeah,
so they were wondering if it was transuranic, as in
a man made element that would not be found in nature,
or if for Me had somehow managed to split up
uranium so that behave like lighter elements, because some of

(22:48):
the stuff that was left over it seemed really similar
to lighter elements on the elemental table, But how could
that be magic? Yeah, and it's fine because he had
actually achieved nuclear fission but did not know it. He
didn't he didn't understand it enough to know that that's
what had happened at the time. And that takes us

(23:10):
to thirty eight. And this is the event that really
creates the need for the Manhattan Project because it takes
place in Berlin. Now, nineteen thirty eight. In Berlin, it
was already a very tumultuous time in Europe, right. World
War two had not yet begun, but Germany had started
to really cause huge problems, including UH cracking down on

(23:36):
the Jewish population already UH, and it was you know,
the whole Germany Austrian alliance was was an issue. And
then there were rumblings about Germany possibly invading other countries.
And then this was also spreading to you know, Italy
as well. Yes, Italy was also invading African nations at

(24:01):
the time. So this was really a tumultuous period. So
in Berlin, UH, Germany was a place where there where
particle physics, theoretical physics had really blossomed at the end
of the nineteenth century beginning of the twentieth century, and
you had a collection of scientists who all were just

(24:21):
interested in furthering our understanding of the universe. They just
happened to be in a place where that understanding was
going to be UH tilted toward the ends of the
German government. So radiochemists Auto Han and Fritz Strassman, we're
using firms method of bombarding atoms with neutrons, and they

(24:43):
found that uranium nuclei, unlike other nuclei, didn't just absorb
the neutrons. They broke apart into two more or less
equal pieces. They became fragments of uranium and radioactive barrium isotopes,
which explained why some of the substances from firms experi
ements resembled lighter elements because they were they were Merriam.

(25:04):
So that was the the scientific explanation of what was
going on with Firm and firm. He's like, hum, that's interesting. Um.
What's also interesting is that this information, because you know,
it also released some energy. Uh. This information was examined
by Lease Mightener and her nephew Otto Frish Uh. Mightener

(25:28):
was a Jewish exile. She had fled Austria and was
living in Sweden and was working with Han and Strassmann
through correspondence. UM and she and Fresh looked at the
results of the experiments and concluded that they released an
enormous amount of energy and that this marked a new
type of process, which was explained by the equals MC

(25:51):
squared equation. So again we see a physical proof of
a theoretical proposition. Right, and this also started bring a light. Hey,
maybe we should really take that Einstein equation thing really seriously. Um.
So Fresh was the one who called the process fission
that's where we get nuclear fission was from Otto Frisha's

(26:12):
description of the of this. He was taking um inspiration
from biological processes and cell division, so that's where he
came up with fission. And just to just to interject
not too much of the political landscape, but I do
think it's important to note a big thing Hack happened
to firm me in thirty eight as well, And why

(26:32):
don't you tell me about that? Well, in he left
Italy to uh receive his Nobel Prize in physics, which is, uh,
you know, it's a pretty good deal. It's like when
you get that tenth stamp on your subway card. Oh.
I was thinking, like, you finally get that star on
the on the Walk of Fame. Yeah, yeah, you finally

(26:54):
get the star, which I think I don't remember which
subway stamp that is. No, it's it's like, I think
you've got to go like at least twelve times. Oh, Mick,
come on, that's a commitment anyway. Well, somehow I'm going
to go out on a limb and say it's because
he was a genius, uh, and the based on his
discoveries for me, leaves Italy to receive the Nobel Prize,

(27:16):
and he never returns because you know at the time,
as you know to your earlier point, the situation in
Europe is at a slow boil, and especially if you
are Jewish, as firm he is, this is uh, this
is a time where you can, like legois, smell a
fell wind. Yeah, there's actually there's a I mean, if

(27:40):
you and I'm sure I know I've talked about this
in a previous episode. I can't remember what the subject was,
but I remember specifically talking about um uh German scientists,
German and Austrian scientists who fled Europe in advance of
the rise of the Nazi Party in Germany. UH, and

(28:01):
then some who stuck around believing that things would get better,
only to find out that in fact was not the case.
And how despite their brilliance and their contributions to science,
because of their their heritage, they were treated, they were
they were pulled away from their work, some of them,
of them were imprisoned. Um. And of course there's a
whole other story we could talk about with the United

(28:24):
States liberating certain scientists to work for them instead of
for the Nazis. That might be it would be a
little bit of Yeah, that is definitely a different too far.
That's actually more in rocketry than it is with the man.
But at any rate, so nine our buddy Leo. He

(28:46):
realizes the work by Han and Strassmann could be the
answer to his failures to produce a nuclear chain reaction,
and that uranium would be heavy enough and commit neutrons
at an energy great enough to cause a split in
another atom. So if you had enough uranium, you could
presumably create a nuclear chain reaction that way. Uh So
this is this renews his interest in the possibility of

(29:09):
creating one of these. Um. He actually asked that for
me and Frederick Jolie Currie refrain from publishing their findings.
He asks them not to publish them because since he's
made this realization that a nuclear chain reaction could be possible,
his fear is that if they publish their findings, the

(29:30):
Nazis will hear about it, and because the initial study
was done in Berlin, they could end up putting this
on the fast track to developing a weapons program, which
would change the course of the war. Yeah, which keep
in mind, this is when the war officially begins, right
when you know, when the World War two start, Well,

(29:50):
people would say that's when Germany invaded Poland, and that's
that happens in the nine. So he asks them not
to publish their findings now for me, says okay and
holds off. But Curie goes ahead and publishes his work
in April ninety nine. So it turns out those concerns
were warranted to Leo turns to the the rock star

(30:15):
of rock stars, because keep in mind, this is an
era when scientists had a certain prestige among the public.
I mean, this is the era of people like Tesla
making headlines and Edison, and meanwhile you've got other scientists
and engineers who are capturing the imagination of hundreds of

(30:38):
thousands of people. He turns to the most influential of
them all, good old Einstein, and Leo says to al
listen here, bat Bubby, Uh that equation you made awesome,
turns out your right problem. Now we know how to
make a practical application of that. Potentially it's gonna take
some years, but the juryman's are already aware of this.

(31:02):
And you know how bad the Germans can be. We're
having this conversation not in Germany. And when I say Germans,
obviously I'm talking about the Nazi Party. I have nothing
against Germans at any rate. So he says, we need
to convince the United States government that we have to
get on this right now, because if we don't, they will,

(31:27):
and then that's just going to be domination for Germany.
And so Einstein, convinced by Leo, decides to write a
letter to President Roosevelt FDR not not Teddy. So he
writes a letter to Roosevelt and expresses their concerns about

(31:49):
the possibility of a nuclear weapon program starting in Germany
and arguing that, uh, the United States really has to
take that endo consideration. Uh. The letter is sent in
August nineteen nine, and on September one, nineteen thirty nine,
Germany invades Poland. World War two begins officially because that's
when you get other nations in Europe declaring war against Germany.

(32:12):
So Roosevelt has a meeting with his close friend and
unofficial advisor, Alexander Sachs, who's not a politician, he's a
financial advisor type. Saxon Roosevelt sit down and on October eleventh,
nineteen thirty nine, they talk about Einstein's letter. On October nineteenth,

(32:34):
Roosevelt writes back to Einstein and says he has formed
a committee made up of representatives from the Army and
the Navy plus sacks to research uranium. Yeah, the Advisory
Committee on Uranium headed by Lyman J. Briggs. Yeah, Briggs
would become another important figure in this in this story.

(32:54):
That has formed officially on October twenty one, nineteen thirty nine.
So this happens fast, right, They talked about on the eleventh,
on the nineteenth rights back to Einstein. On the twenty one,
this new committee meets for the first time. Uh. Briggs,
by the way, was the former director of the National
Bureau of Standards. Now you get Faremi and Leo concentrating

(33:15):
on using carbon in the form of graphite to slow
down neutrons in a pile of you two thirty eight,
and by slowing down the neutrons, they hope to increase
the chances of a chain reaction. But they discovered that
that method would really only be suitable for probably generating
power because it would require too large a form factor
to make an effective bomb out of it. The uranium

(33:37):
didn't react at a level fast enough for it to
be an explosive release of power. Yeah, So Faremi thought
the chances of this being useful in a weapon are
pretty slim, but it could be a really useful way
of generating electricity. Now, meanwhile, uh, if we moved to
nineteen forty, physicists were starting to run into a problem.

(33:59):
You're two thirty eight was not prone to creating these
nuclear chain reactions. They were they were having issues with this,
and that's the most common when that's the one that
is of the world's uranium. Right, So here's your stuff,
but it don't work. It would be like imagine that
you you have, you know, a big battery drawer, and

(34:20):
of those batteries have just a little juice in them.
They're not enough for you to like, you know, you
put them in your RC car and your car just goes.
You know, I hate that. But there's another eight percent
still out there. Yeah, and some of that is uranium
two thirty five, but it's it's usually wrapped up in
you two thirty eight. It's not you know, it's not
like you just find little veins of YouTube out there.

(34:43):
So John are Dunning observed that uranium two thirty five
appeared to be a lot more promising, but only if
you could separate it from you two thirty eight. So
now they're they're thinking, well, if there's some way for
us to separate these isotopes from two from two thirty
eight and concentrate enough to thirty five and one spot,

(35:03):
we might be able to create a nuclear reaction chain
reaction that is sustainable until a significant amount of that
fuel is converted into energy, in which case you would
have either a big boom or a sustained power source.
So we're going for the boom. Yes, so without enriching you,
two thirty five is pretty much impossible to experiment further,

(35:27):
they didn't have a way of doing this, like they figure, well,
to thirty five, according to the math, is better. Here's
the problem. I don't know how to get the two
thirty five out from the two yet right in a
way that would come across come up with more than
just microscopic amounts of you. And we're talking about the

(35:47):
need for kims of the stuff. So it's a problem.
It was also in nineteen forty that the Advisory Committee
on Uranium recommended that the government fund research into isotope
separation and nuclear chain reactions, which the committee did. So
separating two from two thirty five was hard. They're chemically identical.
So you can't use chemistry to do it because they're

(36:08):
going to react exactly the same way. They're telling Masses
differ by less than one per cent, so finding a
way of separating them by mass is also a little tricky.
But one of the more promising methods was the electro
magnetic method. Now, this meant that you would create a
magnetic field generated by a mass spectrometer to separate particles,

(36:30):
and essentially you create a magnetic field, and yeah, I
had the particles come into contact with a magnetic field.
The magnetic field would deflect particles. Particles that had greater
mass would be deflected a shorter distance. Yeah, because it
can't push those as far right. So you could do
this and deflect those particles, but it wasn't exactly fast.

(36:53):
In nineteen forty they estimated that to create a gram
of you two thirty five using a mass spectrometer. In
this a if you took you two thirty eight and
two thirty five together and tried to just get one
gram of you two thirty five, it would take you
approximately twenty seven thousand years. Not not like not the

(37:13):
ideal time frame. Not if you wanted to respond to
escalating aggression in Europe, not not so much twenty seven years.
Probably some multiple conflicts would have had that happened and
resolved during that time. I think Hitler, who was admittedly
an ambitious dude, was only planning on the Reich itself
to be like a thousand years. Yeah, so it would
have been a pretty it would have been a pretty

(37:36):
long long bet. We would have been embarrassingly late to
the party. Yes, So luckily there were other ones too
that they were looking into. One of them was Gassiest diffusion,
which I have suffered from myself an occasion to say
thank you. Gassiest diffusion was that's where you would use
a porous barrier and you would use gas that has

(37:57):
you two thirty eight and YouTube thirty five atoms in
it to pass through this porous barrier. Now, the you
too thirty five, being of less mass, would pass more
readily through the barrier. So you would do this once
and then the mixture you would have would have a
higher concentration of you two thirty five than the previous
one did because fewer of the You two thirty eight

(38:19):
would have gone through. But then you have to repeat
the process, and you repeat the process over and over
and over again. It's kind of like passing a solution
through a filter, and each pass the filter catches more
and more of the stuff you don't want and allows
the stuff you do want to go through. But it's
not full proof. That's why you have to keep on
doing it. TOSS so again, not terribly efficient. John Dunning

(38:43):
focused on that particular method. Then you also had the
possibility of using centrifuges. And a centrifuge, you know it
essentially it spins around and around and around and use
a centrifugal force or tripital force if you prefer, but
centrifical force to to separate out materials. The heavier materials
sink to one end, the lighter materials are pushed to
the top. So in this case, you two thirty five

(39:04):
would be kind of at the top and center of
the centrifuge, and the U two three it would be
would it sinkle down lower and you would skim it
off the top. Centrifuges, however, at the time not terribly reliable.
That was headed off by a guy named Jesse W.
Beams at the University of Virginia. We've got more to

(39:25):
say in this classic episode of tech stuff. After these
quick messages, we're gonna get into the politics. And there's
a guy. I have a feeling that he's come up
and stuff they don't want you to know. Maybe once
or twice. Have you guys ever talked about Vanavar Bush.

(39:47):
We have talked about Vanavar Bush. He is a He
was an American engineer and inventor. He headed the US
Office of Scientific Research and Development. Yeah. Uh, and he
was one of the early uh now, well, okay, he
was the go to guy from military R and D

(40:10):
at the time in the US. He was also kind
of like the liaison between the politicians and the scientists.
It's a great way to put it, because he had
the analytical scientific mind. He had the chops that would
be required from a scientist. Again, like a rock star
to respect you. He's incredibly ambitious as well as effective
at maneuvering through different power structures. This guy was like

(40:35):
he could get stuff done and no offense to the
various stereotypes of scientists. But he probably was better at
playing the game of diplomacy. Yeah, you know, because he
was he knew he understood how that particular science worked.
So he was the president of the Carnegie Foundation, and

(40:58):
then was appointed the head of the National Defense Research Committee,
which was a voice within the executive branch of government.
And under that the Uranium Committee was reorganized. So the
Uranium Committee gets uh kind of a new version, a
new yeah, that kind of mission statement. Um And and

(41:21):
it also meant that it was no longer organized under
the military department, so it didn't have to yeah, I mean,
they could get their funding outside of the military. So
instead of the Army or the Navy deciding, all right,
we're going to allocate this much of our budget towards
uranium research, it was an independent organization underneath this new committee,

(41:43):
um so Bush allocated funds to continuing research in nuclear
power and weapons. But he made some decisions that ended
up um really shaping the direction that the Manhattan Project
would move in. The first decision he made was that
no one on the Middy would be allowed to be
foreign born. No foreign born scientists would be allowed on

(42:06):
the committee. The man Einstein was not part of this party.
He also barred the publication of scientific findings on uranium
research for an indetermined amount of time because again, like
like the the Leo's previous concerns. He didn't want this
any know, the discoveries to make their way across into

(42:27):
enemy hands. So now we're getting up to nineteen forty one.
World War two is in full swing in Europe. UH.
Glen T. S Borg, another important person, identifies element ninety four,
a trans uranium or man made element that was produced
from radioactive decay of an isotope of neptunium. Neptunium is

(42:48):
also a trans uranium element, that's ninety three, So ninety
four he gets to name it. I call it plutonium. Yeah.
And he discovers that one of the features of plutonium
is that's one point seven times more likely to undergo
fission as uranium two thirty five. It loves fission, yeah,
to thirty five loves fishing more than two thirty eight.

(43:10):
Plutonium loves fission more than uranium two thirty five. So
the experiments took place at Ernest Lawrence's radiation laboratory at Berkeley.
So Lawrence again very important here. Lawrence personally felt that
the Uranium Committee was a little slow, that it was
not responding fast enough, it wasn't funding the research. Uh.
And so he met with Van of our Bush and

(43:32):
then Bush saw Lawrence as being really persuasive and and influential,
so he makes Lawrence an advisor to Briggs. You know,
Briggs was the head of that uranium committee. And so
once that happens, suddenly the coffers opened up a little bit,
more and more research gets funded. Uh. Vanavar Bush also

(43:55):
created a committee to report on the uranium program in
the US, and he put Arthur Compton, who was a
physicist who specialized in radiation studies, in charge of it.
So Compton makes a report in May nineteen forty one
and confirmed that either you two thirty five or plutonium
were the most likely candidates for some sort of atomic weapon. Yes. Uh.

(44:15):
And on June one, the United States establishes the Office
of Scientific Research and Development. This is the one you
referred to as Bush being of the head of it.
This is when it was officially made a thing. It
was officially. Yeah, we we had talked to I think
and stuff that I want you to know about about
that time, just a few days before this is actually
was a few days after the twenty two when Germany

(44:37):
invaded the Soviet Union. Yes, so yeah, various things are
hitting various fans right right. The big one being that
there is a lot of incentive to push this research through. Uh. Meanwhile,
James B. Conant, who was president of Harvard became the
new head of the National Defense Research Committee, which was

(44:58):
now an advisory board that would offer guidance on research
and development funding. And guys, we know how not to
interject too much, because we know how confusing it can
be to hear these very long, dry names of committees.
But part of this, part of all this restructuring you
hear about and all these names, it comes because they

(45:21):
were desperately trying to find the best way to approach
this problem. Uh, simply because can you imagine. Of course
there were, of course there were agents from what would
become the Allies in in Germany at the time. However,
the level of access they had was no guarantee. The

(45:44):
only way to be there was, the only way to
know that you would not be the victim of a
nuclear bomb or an atomic weapon was to be first
past the post. So this stuff is I mean, Jonathan,
there were probably some egos involved. No, no, there are
tons of egod but I think I think the I

(46:04):
think the main thing to remember is that although we
hear all these dry names. What they're really doing is
desperately and it does that work correctly, Desperately trying to
find the way to get massive amounts of funding because
they already know it's going to be an expensive service.
Well that and and at this stage in we're still

(46:25):
talking theory, we're still we're still saying that they're saying,
if such a thing as possible, you to thirty five
and plutonium are our best bets that we can't guarantee
it's possible. If Yeah, and that's the thing is that
you've got that's why you have all this research and
development going in. And they're going through multiple lines of inquiry,
right because they don't want to say, well, let's just

(46:47):
look at one and hope that that is going to
work out. There's no let's look at all of them
and find out which ones are the most promising and
concentrate on those. So, uh so, Conan is head of
this board that's going to look at these different um
proposals and decide which ones are the ones most the
most warrant additional funding. So if you are the head

(47:10):
of a research department it's a Columbia university, you're more
likely to receive funding than if you're some yahoo in
your backyard saying if I smack these two rocks together,
sparks fly. So that's the important part that this is
all about. Like the goal here is pushing forward this research.
So under this new organization, the Uranium Committee becomes the

(47:33):
Office of Scientific Research and Development Section on Uranium. And
that's a really long name and they recognized it, so
they code named it S one. So as one becomes
this specific committee that's looking at uranium research, can it
be used as a way of making a weapon? July

(47:53):
a group in Britain's National Defense Research Committee which was
code named MAUD in a U d uh. They they
their whole purpose was again to look and see if
a nuclear weapon could be practical. They submitted a report that,
based upon their calculations, you could use tens of you
two thirty five to create an enormously destructive bomb and

(48:18):
that could be dropped by existing aircraft of the time
and it would probably be two years out in development,
like within two years of concentrate development, such a bomb
could be built. So by n Britain shares this report
with America, and because Britain recognizes that America has an
enormous resource in scientific expertise. So that report specifically recommended

(48:45):
using gaseous diffusion to separate you two thirty five from
you two thirty eight and outright dismisses the idea of
using plutonium. Stay tuned for the exciting conclusion of this
text off classic episode right after we take this break.

(49:09):
So the Brits say, you should use to thirty five,
you should use gaseous diffusion to get your two thirty
five from two thirty eight, and forget about plutonium. It's
a dead end. That was their recommendation. So meanwhile you
got fair Me, who becomes the head of theoretical studies
at the Ranium Committee. And keep in mind fair Me
is the plutonium guy. Yeah, so there when you say

(49:32):
there are probably egos involved, yes there were, And there
were people who were absolutely convinced that their approach was
the one that was going to be the most economical,
the most efficient, the most scientifically sound. So in these arguments,
do you think there are a lot of those you
fools moments? You fuse ye all be uh in dramatic

(49:59):
like style? Uh dialects? Well, not one. In October, Bush
meets with Roosevelt to discuss the state of research. He
receives instruction from Roosevelt to continue research and development, but
it was expressly told don't build a bomb until I
tell you to, which was fine because they were at

(50:22):
least a few years away from being able to build
one in the first place, even under ideal situation. November
six one, Arthur Compton reports that, based on his calculations,
a critical mass of YouTube you two between two and
one rams would produce a powerful fission bomb uh and
could be created with an investment of around fifty million

(50:44):
to a hundred million dollars in isotopes separation technologies, which
turned out to be crazy optimistic. Yeah, they were low
ba Yeah. So obviously the Brits come up with ten
kilograms and Arthur Compton's and that's probably gonna be somewhere
between you in a hundred. It's a slightly larger range.
December seven, nineteen for one very important day in World

(51:07):
War two, that was the bombing of Pearl Harbor. It's
when the Japanese attack Pearl Harbor that brings the United
States into World War two and sets this all on
an even faster track than it was before. So January
nineteenth ninety two, Roosevelt gives Vanavar Bush to go ahead
to pursue the development of an atomic bomb. So we've

(51:27):
gone from keep on researching this to see if it's
possible to build one of these, keeping in mind that
we're still working in the realm of theory. Yeah, and
the but the funding flight gates were open. They said, uh,
no more um figuring out how to do it now,
that just becomes a step in my mandate to you

(51:49):
to give me a working atomic bomb. And they form
what is called the Top Policy Committee, which was led
by Vanavar Bush. They also had Vice President Henry A. Wallace.
James Knitt was part of it. Henry L. Stimpson, who
is the Secretary of War, was part of it, and
General George C. Marshall, who was Chief of Staff at

(52:10):
the Army, was part of it. And the Top Policy
Group decided to pursue five strategies, four different isotope isolation
methods and the use of plutonium as the five different
methods of potentially creating an atomic bomb. The reason they
decided to look at five again was because none of
the five had so far emerged as the clear superior method.

(52:35):
So because they didn't know, they said, well, we would
rather go ahead and have all these different groups, all
of which have brilliant engineers and physicists attached to them,
to independently work on this stuff. They're motivated by one.
Many of them come from Europe and they see what's
going on in World War two too. Many of them
have egos, and they want to prove that their method

(52:57):
is the right one, and three they're they're genuinely interested
in the science. So March of nineteen forty two, UH, Lawrence,
the fellow who ran the cyclotron and Berkeley, pursues the
electromagnetic isotope separation method using a cyclotron as a mass spectrometer,
and he's so successful that vanavar Bush sends another message

(53:20):
to Roosevelt saying, Hey, if this pans out, we might
be able to have an atomic bomb as early as
nineteen forty four. That would turn out to be optimistic. Uh.
In April nineteen forty two, Arthur Compton, who was guiding
research into plutonium. So we got Lawrence with electromagnetic isotope isolation.
Now we've got Compton who's looking into plutonium. He's funding

(53:42):
the work of j. Robert Oppenheimer at Berkeley, who may
be familiar to some of you, especially if you've ever
checked out of our shows. Yeah, Oppenheimer comes up a lot.
I mean, every single person that I'm mentioning here could
warrant an entire episode and stuff you missed a history class.
I'm sure it has covered many of them in the past.

(54:04):
So Oppenheimer and Fermi also gets funding from Arthur Compton.
He says, all right for me, he's got a pile,
a nuclear pile he's working with at Columbia University. Also
funds Eugene Wigner's theoretical work at Princeton. Now over at
the University of Chicago, Compton secured some space to create
his own uranium and graphite nuclear pile. By securing some space,

(54:29):
I mean he converted a racketball court underneath the grandstand
at stag Field at the University of Chicago into a
nuclear pile. This, by the way, would scare the heck
out of everybody later on, because he didn't bother to
tell anyone that that's what he was doing. Well, well, well,
let us remember this was a top secret project. And also,

(54:52):
if we're talking, I don't know why my voice was
And also if we're if we're talking about public safety,
then you know, the dangerous rationalization people can always make
is what is the safety of the people above in
a grandstand or even the University of Chicago compared to
the safety of the world. But what I'm telling that

(55:13):
he was a maverick, Well, I tell you now uh
he uh into in his defense, this approach that he
was using, which was very similar to Faremi's approach, was
low energy. It was not something that was perceived to
have risk of it becoming a runaway reaction. It was
it was more again to study the actual physics involved

(55:35):
to better understand it, and posed very little threat to
the people of Chicago. Using the design that he used.
He wasn't using it. He was using a design that
didn't require a cooling system or a shield because he
wasn't It wasn't the super high energy type of reactions

(55:56):
that he was he was looking into. Two Compton Arthur
Compton asks J. Robert Oppenheimer to take over research into
fast neutron interactions to determine the necessary conditions for a
critical mass to explode. So Oppenheimer takes on that work.
Then of our Bush asks James Conant, the guy from Harvard,

(56:17):
for recommendations on how to proceed, and the S one
Leadership Committee decides that instead of focusing on one area
of research, all of them still have to be funded
and accelerated. They still weren't certain which of these were
going to end up being successful. Is still too early,
so they say, well, we can't, we can't pull the
trigger on one of these yet, we still have to
keep on going. And in June two, the Army's involvement

(56:39):
in the project, uh really picks up. You have a
guy named Colonel James C. Marshall come into the picture.
So James C. Marshall, he's in charge of the Army
Corps of Engineers involvement in this project, and the Army
Corps of Engineers their main job was to secure sites
that they could then use to build facilities on to

(57:02):
test out the theory that was being generated in these
various camps. So in your normal operations, if there's not
a war going on, what you would typically do is
you have the research and development work that is starting
to be promising. You would build a pilot plant that
would test these things out and it would be designed

(57:25):
in such a way that you can make rapid changes
to the plants design in order to best fit whatever
the process. Yeah, exactly, so you might say, oh, it
turns out that this design we came up with isn't
the best one, we should change it to this. A
pilot plant is the kind where you would be able
to do that. Then once you figured out what was
the best approach, you could build a full production facility, right. Yeah.

(57:48):
And at this time I believe the US Army Corps
of Engineers was based in New York. Yeah. The headquarters,
it was supposed to be a temporary headquarters, was on
Broadway in Manhattan, because you want to keep it locating. Yeah,
so they called it the Manhattan Engineering District, or sometimes
just the Manhattan District and sometimes just Manhattan. And that,

(58:11):
in fact, is where the Manhattan Project gets its name.
It gets his name from James C. Marshall's headquarters in Manhattan.
And he was really he was on the phone calling
up potential land, you know, landowners who could potentially sell
him the land necessary from the build these facilities. And
the crazy thing here is the Army Corps of Engineers

(58:33):
and and these scientists are essentially skipping the pilot stage.
They're going straight from well, we're pretty sure this is
the way it's gonna work to let's build this facility
to do it. And by skipping the pilot stage it
causes huge headaches down the line. But at the same
time they said, well, we don't have the luxury of
time to go the scientifically responsible routes, so we have

(58:56):
to do it this way. So, uh we get the
Manhattan Project. Technical the project has a different name. The
the official code name for the project, because it's super secret, y'all.
Is the Development of Substitute Metals or sometimes the development
of substitute materials depending upon which citation you're reading, or
d s M. That's the official code name, but everyone

(59:17):
calls it the Manhattan Project. Uh So we are now
at the point where the Manhattan Project comes into being,
James C. Marshall being in charge of it, kind of
being an administrator to make sure that the scientists are
getting the resources they need. And this leads us to
the conclusion of this episode so that in our next
episode we can focus specifically on what happens with the

(59:39):
Manhattan Project. You're going to have a whole list of
new names. This is really just to prepare you in
case you ever decide to read the Game of Throne series,
so that way you know how to handle all these
different characters, because it's kind of similar in that respect. Um. So, Ben,
we're gonna be talking about like super top secret stuff

(01:00:01):
in the next episode. Keeping in mind the Manhattan Project
was a secret from almost everybody from two when it
came into existence to mid nine after the bomb has
dropped on Hiroshima. So this is when it comes to

(01:00:22):
stuff they don't want you to know. This is it.
You talk about massive government conspiracy. It doesn't get much
bigger than this. We're talking a hundred thirty thousand people
or thereabouts employed in somewhere or another, most of whom
had no idea what they were contributing to. Right, Yeah,
this is uh, this is bigger than a you know,

(01:00:43):
this is something that we talked about our previous fifty
one podcast. I'm I'm excited. Yeah, so let's see. I
guess this will be a little bit of a cliffhanger
for the listeners. Yeah, so you guys have to tune
in next week, same bad time, same bad channel. You know,
it's always weird to talk about enjoying an episode that's
about the technology that is so incredibly destructive, but I

(01:01:06):
hope you learn something, and of course next week we
will continue the discussion about the Manhattan Project. If you
have suggestions for topics I should cover in future episodes
of tech Stuff, please reach out and let me know.
The best way to do that is on Twitter. To
handle for the show is tech Stuff hs W and
I'll talk to you again really soon, y. Tech Stuff

(01:01:32):
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