Hot answers tagged

50

You cannot optimize a zero. First of all, fuel bars in nuclear reactors count hundreds or thousands of those pellets. It's like I ask you to invent the car engine just by giving you a drop of gasoline. Furthermore there is no way for a person with the knowledge level of 14th century to have the faintest clue that what they are handling is a radioactive ...


19

Realistically, what you have is a very small amount of superheated hydrogen gas escaping in the environment. Other than ruining a very expensive piece of machinery, and a loud noise, just about nothing will happen. Fusion reactions cannot take place under natural conditions on Earth, so the reaction will stop as soon as containment is breached. The ...


19

The inhabitants would not have the faintest idea what they were they would just be rather curious small round cylinders. They would probably find a use for them as a sling stone or similar but they would impart zero understanding of nuclear physics. One of the biggest problems being the completely different culture and mind set before the enlightenment. ...


16

Unfortunately, it wouldn't increase the yield. When matter and antimatter annihilate each other, yes, they do liberate a huge amount of energy. But, you don't get energy for free - no matter how it's produced, creating antimatter will take up exactly as much energy as annihilating it will release. So, even if it were plausible that a fission or fusion bomb ...


14

Any size would be practical, including a single individual Though we don't call them such, Radioisotope heater units are technically small nuclear reactors, which only give out about a watt of heat. The description that you gave requiring an operator and control rods does imply a larger unit, but there is no reason to believe that this single purpose ...


14

The fourteenth century is centuries too far back Physics won't be invented for another 300 years. Isaac Newton essentially invents the discipline in 1687 with the publication of Principia. He had to invent a new branch of mathematics in order to do that. After that happened, several hundred years of progress in physics was required before people ...


13

Ejecting spent nuclear fuel is not as simply as dragging things to the airlock and giving them a push. You need to be able to enter the reactor, extract the spent fuel, replace it with fresh fuel, carry it to the exterior of the ship, and give it enough of a push that it won't damage the ship. You need to either make provisions for protecting the crew member(...


11

Because recycling? Spent nuclear fuel rods can be reprocessed to get nuclear fuel. This is fairly efficient AFAIK but in the real world comes with the issue that some of the material generated could also be used for nuclear weapons. The efficiency apparently depends on the reactor type, so that has to be part of the design. This might make sense for a long ...


8

So, crawling through that wall-o-text, you seem to be proposing a closed-cycle gas core nuclear reactor with PIDEC to provide power for a mecha, right? Lets ignore the weirdness about "transferring thermal energy", it isn't a totally daft idea on the face of things, but: Nuclear fission reactors have a minimal size. The "nuclear lightbulb" rocket designs ...


7

Expanding my comment out into an answer: Temperature is not heat. Imagine you have a boiling pot of water on the stove. You can reach through the steam to turn off the element. Steam has a high temperature (100C), but it doesn't have much heat, because there's not much of it. You could also stick your hand in the boiling water, but I wouldn't recommend it; ...


7

how likely would a solar flare cause a nuclear winter? Unlikely, bordering the impossibility. A nuclear winter is defined as the severe and prolonged global climatic cooling effect hypothesized to occur after widespread firestorms following a nuclear war. The hypothesis is based on the fact that such fires can inject soot into the stratosphere, where it ...


7

There is some reason to believe that the world was heading into an ice age when the industrial revolution started. The industrial revolution of course added a great deal of carbon dioxide to the air. If you are willing to believe that this prevented the ice age, nuclear winter combined with an end to burning fossil fuels could lead to the previous ice age ...


7

Your planet is kicking out huge quantities of radon gas. https://en.wikipedia.org/wiki/Radon Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium ...


7

I agree that a possible solution would be to add in a source of high-energy ambient neutrons. Cosmic rays are a possible neutron source, at least at high enough altitudes and assuming the uranium does not have adequate shielding. A strong spike in cosmic rays could then provide such a neutron source; in turn, as one of the major sources of Galactic cosmic ...


6

Hit a large gypsum, or other sulfurous compound, deposit. The main reason the that Chicxulub impact caused long term climatic chaos wasn't the initial rocky impact ejecta, they were bad but what caused hundreds of years global temperature oscillations was that the impact happened in an area rich in carbon and sulfur bearing rocks, mainly limestone and gypsum,...


6

If you simply want an ice age, you may not even need the nuclear winter. Simply let the Sun enter a 1000 years long period of slightly lower intensity. It could be large enough to counteract anything humanity does to heat up the climate. We have evidence that the Sun's output is not constant over large timescales. It is theorized that such low activity was ...


6

when warhead size increases it derives higher and higher share of its energy from fusion, thus it becomes relatively cleaner and cheaper (per megaton) Although this claim has popped up before, it isn't strictly true. Whilst there is a lower size limit for a fission device, it isn't necessarily possible to scale up a fission-fusion device to arbitrary sizes ...


6

Surface gravity of a neutron star is in excess of 1011 Earth-gravities. What sort of mechanism are you proposing that can lift up bulk quantities of matter from that sort of gravitational field? Teleporters? If you can teleport, you can almost certainly produce much more interesting and sophisticated things than mere "nuclear weapons". The nuclear pasta isn'...


5

Humans consume only a tiny fraction of any given body of water making poisoning a natural water sources relatively inefficient. That said, the water pumping stations in small-to-mid-sized towns tend to be pretty lax in their security, and all of the water that they process goes straight into people's homes. Insert your payload directly into the station's ...


5

Are there any fundamental obstacles to using a nuclear explosion as a trigger for antimatter generation and thus considerably increasing the yield No... What you refer to is the yield limit (I believe it was first pointed out by Ulam) to a fusion device, caused by the explosion disrupting the conditions that allow fusion to take place. By carefully ...


4

Skeptical about antigravity. I already bought muons and heavy counterparts of nucleons. I am ok with other ones. I buy the heavy matter. I like the stable superheavys because everyone likes that. The unstable light ones is a cool ramification; OK with that. As Dutch points out you need some other route than supernovas to get this stuff. Possibly it is ...


4

The Vasily Arkhipov scenario, with a twist. Many answers have hinted at just how important it would be to determine exactly how the specific scenario plays out, but I haven't seen any take this concept and run with it. During the cuban missile crisis, Vasily Arkhipov is often credited with preventing a Soviet nuclear strike and, potentially, an "all out ...


4

Setting aside the issue of what exactly Nuclear Pasta is, and if it would still be useful after removing it from the star (I don't know, so I won't tackle it)… No hard-science fiction technology I can think of would allow anything we could build to survive on the surface of a neutron star. The gravitational field on a neutron star's surface is about 200 ...


4

Dangers you say? OK, let's assume it's a nice big deep pan pizza, and it weighs 500g (let's stay metric for the sake of the math). There's a nice equation E=mc2 that we can work out how much energy that 500g needs to be created, which equates to 44,937,758,937MJ of energy. The Hiroshima atomic bomb converted approximately 700mg (or 0.7g) material (62,912,...


4

You know, forget all the nuclear stuff, what we got here is ten objects having IDENTICAL (from a 14C perspective) dimensions and weight. That has serious value because all of a sudden I can give one of those to a blacksmith and say make me 10 sets of bearings that this thing will exactly fit into, and I can go to ANOTHER smith and say make me ten axles ...


4

The short answer is NO - a biological fission reactor is also a flawed design and it's going to cook your biological organism so it's just not going to happen. The energy cost alone to reach break even point is far beyond the biological framework we live in to store and release in such concentrated amounts. That said, it is perhaps important to note that ...


3

The fireball of a nuclear explosion develops roughly along a spherical pattern, before it starts interacting with the shockwave bouncing back from surfaces it hit. When the nuclear explosion happens underground, it produces a bubble of vaporized rock, surrounded by cracked rock. Once the vaporized rock cools down the pressure cannot sustain the load and ...


3

Yes, there's a huge fundamental stumbling block. Conservation of energy. The energy to create the antimatter has to come from the nuclear fission and/or fusion of the "trigger", so the net, final yield can't exceed that of the nuclear material in the original bomb. Now, John W. Campbell once wrote a series of books in which, among other completely ...


3

As a general principle, all space-based hardware is "hardened" against radiation, at least in the sense that someone will have run the math on the probability of a radiation event causing undesired behaviors such as single event upsets. Informally, everything that goes into space is @&#$ expensive, and is used in situations where people really don't ...


3

TL;DR I'd propose that weak force life has a tiny change of existing in environments where particles travel at high speeds. A possible example is the jets produced by an active galactic nucleus. At the high energies (and high speeds) particles reach in these jets, the range of the weak force could be sizably extended to the point where it is less negligible ...


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