Did we discover nuclear technology “too early”

[kerbiloid]

6 minutes ago, TheSaint said:

Okay, I wouldn't go that far....

The university didn't leave me chances to not do that...

[awsumguy76801]

3 hours ago, TheSaint said:

Case in point: That's actually not how nuclear fission works. At all. Allow me:

• One of the major misunderstandings that people have about nuclear fission is that they imagine that neutrons smash into the uranium atom and break it apart, like through kinetic energy or something. That's not what happens. What happens is that the isotope uranium-235 absorbs a neutron and becomes the isotope uranium-236, which then immediately decays through fission, releasing fission fragments, fast neutrons, and a whole ton of gamma rays. Which is why it is easier to sustain a fission reaction with a population of low energy (thermal) neutrons than it is to sustain it with a population of high energy (fast) neutrons. Because it is easier for uranium-235 to absorb a low energy neutron than a high energy neutron. Which is counter-intuitive to the popular image of nuclear fission.
• The split atom (or fission fragments) are not what sustains the chain reaction. That's the released neutrons. Each nuclear fission reaction releases (on average) 2.85 high energy, or fast, neutrons. But, as I said above, uranium-235 doesn't like to absorb fast neutrons. It can, but the chances of the reaction happening are much smaller. You need a much higher density of uranium-235 to sustain such a reaction, which would require you to enrich your uranium to a much higher ratio of uranium-235 to uranium-238, thus weapon-grade uranium. This is the principle difference between a nuclear reactor and a nuclear weapon. Nuclear weapons create an environment in which the fissile material can maintain a chain reaction based solely on the population of fast neutrons (a condition known as "prompt criticality"). Nuclear reactors are specifically designed so they cannot achieve prompt criticality, they cannot sustain a chain reaction with fast neutrons. They require the neutrons to have their energy levels reduced, or "thermalized" in order to produce enough fission reactions in their concentration of uranium-235 to sustain a chain reaction. Which is why reactors have moderators. In light water reactors, the moderator is water. In graphite-moderated reactors the moderator is graphite. The moderator is a substance which is introduced around the nuclear fuel which reduces the energy levels of the fast neutrons through collisions, producing a population of thermalized neutrons which then sustains the chain reaction.

Honestly, the math and physics behind it isn't that complicated. I learned what I know in six months at Naval Nuclear Power School. I couldn't design a reactor, but I understand how they function, and how they malfunction. And I'm not a genius. I'm above average. I was tested back in grade school and my IQ was 130, which is above average, but not genius. And, trust me, a large fraction of the guys who graduated NNPS were not above average. I know, I had to train them when they got to the fleet. You don't have to be a genius to understand nuclear physics. It's not magic or super-science. You just have to take the time to learn it.

So, to get back to the original subject, I've never felt like nuclear technology was out of its time or place. Simply because I understand it.

Thanks for explaining how it works because i always thought the force of the neutron literally split it in half. dunning kruger effect. im not good with math (i still got an A in physics thanks ksp) so i always try to stay away from the math and just assume everything is hard.

[magnemoe]

6 hours ago, awsumguy76801 said:

Thanks for explaining how it works because i always thought the force of the neutron literally split it in half. dunning kruger effect. im not good with math (i still got an A in physics thanks ksp) so i always try to stay away from the math and just assume everything is hard.

I knew about slow neutrons but thought it was just staying longer inside the reactor if slower so higher chance of hitting an atom. Thinking about it this is mostly relevant in an gas and not so much in an solid. 

[JoeSchmuckatelli]

10 hours ago, kerbiloid said:

almost kindergarten with shovels

Actually not far off if you think back to Curie et al grinding pitchblende.

https://www.newscientist.com/article/mg24532740-400-radioactive-review-a-reimagining-of-marie-curies-luminous-legacy/

There is a scene in the movie that was (God, please forgive me)... Illuminating 

9 hours ago, TheSaint said:

Okay, I wouldn't go that far....

The problem with learning how to do something difficult is that later on you forget how hard it was to learn in the first place. 

[Hannu2]

I do not think it is true. Basic nature of humans do not change during centuries. New tech is laways used first for war, if it is possible (and nuclear technology certainly is). Then for enslave others and make profit without caring environment or health issues. We can think such tinghs and make reasonable regulation after severe problems and even after that there are people who want to abuse things criminally to bad purposes.

 

If researchers invented fission now or 2300 research would be immediately prohibited for companies and civilian universities and investigated only in large state's military research departments and their contracted companies. There would be period of nuclear tests and heavy bomb building, severe accidents and probable small nuclear war before proper regulation and civil use as energy source.

[kerbiloid]

On 6/20/2024 at 4:48 PM, JoeSchmuckatelli said:

The problem with learning how to do something difficult is that later on you forget how hard it was to learn in the first place. 

The fun fact is that these difficulties took less than a human lifespan (1880s-1940s).

And if they hadn't spent years on the tritium extraction, and used the Becquerel's uranium sample immediately on the beryllium rays discovery (just as the mysterious goo), it would take a decade less.

Edited June 21, 2024 by kerbiloid

[kerbiloid]

The nuance is that the uranium ore (i.e. a mix of uranium oxides) have several outstanding properties:

It's not very rare.
Found almost everywhere, from sulfic ore mines to seashore sand.
Because U is a lithophile element. Instead of sinking down like Au, it stays bound in the upper layers of the lithosphere.

It looks bright and sometimes colored, so would be inevitably noticed.

Spoiler

U is chemically active (close to calcium), so its oxides willingly take part in any (al)chemist tricks.

Spoiler

It's very dense, and thus heavy.

It gives beautiful green glass, thus is used in glass pottery since the beginning of times.

Spoiler

It fluorescents

Spoiler

Thus is one of the first candidates to be studied on the fluorescence discovery.

It's radiating, and the photomaterials are very sensitive to it.
Just ~5 roentgen is enough to make a photofilm completely black.

It contains radium and polonium as by-products, so is the first candidate to study once they start experimenting with particle detection.

It's fissile, so will be irradiated with the very first neutron sources among other materials, and will demonstrate the positive loopback of neutrons amount.

This means that no metallurgical civilisation can just pass by it.
Whatever the sapient species was doing with it, anyway it will quickly result into a nuke.
Actually, once they have started making jars, it's just a countdown to turn them into nukes, because such green color can't be just ignored.

Spoiler

 

Edited June 22, 2024 by kerbiloid

[JoeSchmuckatelli]

9 hours ago, kerbiloid said:

This means that no metallurgical civilisation can just pass by it.
Whatever the sapient species was doing with it, anyway it will quickly result into a nuke

You have laid out this argument quite persuasively.  I'd never really thought about nuclear power (and weapons) being an almost inevitable discovery 

Probably because Freshman Chem was a 300 person lecture by a disinterested Grad Student who barely knew his stuff and had no idea how to teach.  (Also - I was 18, an indifferent student and easily distracted by the bounty of college life) 

 

Edited June 22, 2024 by JoeSchmuckatelli

[Exoscientist]

On 6/19/2024 at 3:01 PM, Nuke said:

star trek's timelines are too screwy. everyone wonders what the antique police box is doing in section 31.

I’m not as familiar with the later Star Trek series. What series and episode uses an antique police box for “Section 31”?

  Bob Clark

[magnemoe]

On 6/20/2024 at 5:33 PM, Hannu2 said:

I do not think it is true. Basic nature of humans do not change during centuries. New tech is laways used first for war, if it is possible (and nuclear technology certainly is). Then for enslave others and make profit without caring environment or health issues. We can think such tinghs and make reasonable regulation after severe problems and even after that there are people who want to abuse things criminally to bad purposes.

 

If researchers invented fission now or 2300 research would be immediately prohibited for companies and civilian universities and investigated only in large state's military research departments and their contracted companies. There would be period of nuclear tests and heavy bomb building, severe accidents and probable small nuclear war before proper regulation and civil use as energy source.

The first reactor was not an huge project. 
https://en.wikipedia.org/wiki/Chicago_Pile-1

Building the first nuclear bomb in  3 years after the 1 W reactor was an mega project. 
With no pressure things would gone much slower but sooner or later some would figure out the bombs

[kerbiloid]

56 minutes ago, magnemoe said:

Building the first nuclear bomb in  3 years after the 1 W reactor was an mega project. 

They could easily turn the 1 W into the first nuclear bomb if they had enough enriched uranium to that date.

Just by missing with the graphite amount.

Say, the Leipzig group was on the way to it.

[Nuke]

13 hours ago, Exoscientist said:

I’m not as familiar with the later Star Trek series. What series and episode uses an antique police box for “Section 31”?

  Bob Clark

the point was it was so screwed up they had to consult the doctor as to who to fix it.

also timelines were pretty screwy by the time 90s trek came to its closure.

[magnemoe]

14 hours ago, kerbiloid said:

They could easily turn the 1 W into the first nuclear bomb if they had enough enriched uranium to that date.

Just by missing with the graphite amount.

Say, the Leipzig group was on the way to it.

Define easy  Generating enough enriched uranium was an megaproject, granted it could be done cheaper with more time but its still an major undertaking.