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by 3eb7988a166316 hours ago |
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upvoteby onion2k15 hours ago|
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If I did have fully pure Pu-241, would that be a better fuel than U-235?

Also not a physicist, but I assume from the fact that the OP is asking the LLM this question to trip it up, the point is that U-235 is better even if you have an abundance of both. It's scarcity of Pu-241 leads to the lack of data in training, not that it's actually better.

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upvoteby 3eb7988a166314 hours ago|
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Again, really speaking out of my depth, but if there is a lack of plutonium training data, I would assume the LLM answer would be the far more commonly described U-235. To respond otherwise means there is some existing association with Pu-241 being better.
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upvoteby Skwid11 hours ago|
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That's 2.5% more neutrons, surely that must be better!
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upvoteby tryagainian11 hours ago|
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> Which would ignore that jet fuel is going to be a multiple of the gasoline price.

That doesn’t sound right. If my Duck Fu is any good, jet fuel is currently going due US$3.00 per gallon, avgas (leaded petrol) at $3.30, and gasoline at $2.88 gallon.

There’s nothing much special about jet fuel, it’s just kerosene, same as RP1 (Rocket Propellant), heater fuel, and lamp oil you can buy from the hardware store, with a touch of something to stop it gelling at low temperature if I understand correctly, but also jet fuel tanks are heated if I recall correctly.

I believe standard diesel fuel will also works in jet engines, but kerosene is cheaper.

I’m not in the US, and if I understand correctly their gasoline (petrol) price can vary greatly from state to state, California being the worst? Is that right?

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upvoteby genewitch1 hours ago|
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in 2012 i owned a car that could run 100 octane fuel, and that was $9 a gallon. a few more octane and you get Jet-A minus the additives.

according to jetfueltracker jetA is about $2 more than 87 octane right now and about $1 more than 93 octane. and still somehow cheaper than diesel.

I'm not used to seeing jet fuel this cheap, luckily there's none near me to waste money on.

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upvoteby nullc5 hours ago|
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post says delayed neutron fraction, I presume if were enriched with pu-241 the band between critical and prompt critical would be non-existent and you'll have made a bomb.

But I'm just riffing off the parent poster's text.

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upvoteby teaearlgraycold11 hours ago|
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It’s tough to write good questions for LLM evaluations. They’re so good at picking up subtleties they can pass a multiple choice test when given only the answers and not the questions.
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upvoteby cyberax12 hours ago|
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A higher delayed fraction of neutrons makes it easier to control the reactor. Without delayed neutrons you can only make a bomb.
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