hairytrog

one solution to maintain stable population despite low birth rates is to selectively birth women. japans 1.3 babies per women would more than sufficient. read about it here: https://lvenneri.com/blog/sexratioed

IT kind of is true. Sure the death count directly attributable to nuclear reactors is low. But Fukushima caused the entire countries fleet to shut down - to the present day. Safety isn't about lives lost or health, it's about financial repurcussions of the accidents - both directly at the site (take a look at Fukushima today) and the effects on the wider industry, shutting down all the surrounding power plants, and forcing Japan to import fossils to compensate.

I think that's fair. I bet new large power plants will get the NuScale treatment and reduced exclusion zone though.

Molten-salt-fuel reactors, as described in this article, are so lame... "It's already melted, so you can't have a meltdown." lol. More seriously, molten-salt-cooled reactors have some promise. They use solid fuel, usually TRISO particles, and are cooled by molten salts, which we now have lots of experience with from solar salt power systems. If you are interested in molten-salt-cooled reactors outside of this lame press release - check out Kairos Power. Their website sucks butt. But they are the main player in molten salt-cooled reactors - funded by Henry Laufer of Renaissance Technologies. They actually have the engineering and financing to get one built, and are reportedly doing very well with NRC (unlike OKLO - lolz).

Not sure it's a justified reduction in exclusion zone. Yes they use natural circulation to get rid of decay heat if they lose power to run the pumps. BUT - they can't tolerate multiple reactors failing at once, they can't tolerate more than a few control rod withdrawals, and they can't tolerate clogging of the flow channels - Which to me, seem like reasonable accidents. The reduction in exclusion zone for NuScale is not really justified. If they get a reduction, you can expect the big ass reactors to also get a reduction...

Which is equally a problem for a molten salt cooled reactor. If molten salt leaks or pumping stops, you're gonna get a melt down in your molten salt reactor. That is unless it's running at super low power density - like these guys: https://www.usnc.com/mmr/, in which case no cooling fluid or pumps or even natural circulation apparently are needed to keep it from melting.

Dark matter is probably a grouping of several phenomena like this. Should not discount MACHOs just because it doesn't explain all the dark matter observations. I think I remember reading in Carroll's Astrophysics Intro that MACHO's can explain about 10-20% of dark matter. Dark matter could be potentially be explained fully by multiple dark matter explanations, each adding to the overall phenomena.

This is not true. Every power plant that produces waste must pay money into the waste repository fund totaling nearly $50B - which is probably overkill for building a long term facility by a factor of 5 or more.

Nope. These reactors can be placed anywhere. They used air cooled condensers, which is only possible whe nyou have higher temperature heat than conventional light water reactors in use today. It's 350 degrees C versus 600 degrees C. So you can stick these in the desert no problem.

Something that isn't begin mentioned, is that a lower IFR partially reflects the reduction in at risk groups. Those most at risk of dying have already succumbed to the disease.

Only reason Russia is different than China is Russia is tiny. Lower GNP than Texas.

like this one? https://usnc.com

Here's some footage of Monju - pretty scary: https://www.youtube.com/watch?v=DRJGHWbIxC0

Not quite. 80% of the energy in D-T fusion reactions are released as neutron energy. I sure hope most of that will be used for generating electrical power rather than breeding tritium... :) The dpa rates and helium embrittlement are way higher for fusion and fast fission reactors than for thermal fission reactors. See Figure 3 and 5 of https://www.annualreviews.org/doi/abs/10.1146/annurev-matsci...

Point 2 is highly debatable. DOE is funding TerraPower's Natrium (Bill Gates company) which is a fast reactor, to the tune of 2.5B as part of the Advanced Reactor Demo Program. So a lot of people in the industry believe fast reactors can be commercially viable.

If you accurately estaimted the pain and time required to complete something, you'd never get started.

“IF YOU DON’T READ THE NEWSPAPER, YOU’RE UNINFORMED. IF YOU DO, YOU’RE MISINFORMED.” - Mark Twain (1835-1910)

This could also help the planned helium cooled nuclear reactors like this one: https://usnc.com/mmr/

A good example of solving the wrong problem.

Maybe this will play out like nuclear technologies. Incredible potential for good also means incredible potential for bad. For nuclear, the good was roughly limitless energy at very low environmental cost and low human labor. The bad was nuclear weapons material and nuclear accidents. After the accidents, the nuclear industry in advanced countries basically goes into sleep mode, maintaining existing assets, but unable to expand or grow. Perhaps the lab-leak will have the same result for biomed sciences. Accident leads to millions or tens of millions of deaths and industry must go into stasis. You might say the gain-of-function research is sufficiently differentiated from normal biomedical research that they don't get grouped together. But I doubt it. You can probably do gain-of-function in any old bio lab. The only thing stopping it is the good intentions of the users.

The effort to cause massive societal disruption and destruction is so much easier for bio based weapons than for nuclear. In nuclear, you need so many things to line up if you're building a weapon from obtaining the requisite materials, enrichment, weapon design and electronics, delivery vehicles; and so many things to go wrong if you are going to have a consequential nuclear accident. In contrast, bio weapons can be developed in a dinky lab, deployed, and then self-propagate worldwide.

America may yet prosper.

Which sensor was that stefan_? maybe I worked on it

if the measurement time is short enough, (<1us capturing at 60 fps), the probability of interaction is low even with large number of cameras. Even then, some temporal filtering and intelligent time offsetting to separate signals, can usually fix the problem.

It only matters if you need physically accurate data - ie if your brain can't process the multi path error and correct for it. A bat sees in multi path error and has no problem with it. I assume a machine vision system can learn to perform with multipath error and indirectly account for it. ie, it sees an apple with multipath error, and still knows it's an Apple.

There are options to fix multipath and recover the underlying ground truth

1) you can do a reverse raytrace and iteratively correct for the error - somewhat expensive, but there's tricks and shortcuts to accelerate

2) hardware fix to measure the multipath component separately and subtract / correct it - there's several ways to do this - there are some patents on it that I've worked on. The same methods also can remove background signal from ambient light.

there's these guys: https://usnc.com/careers/

- there is waste, it's just shorter lived than fission waste and lower in quantity. The expectation is that fusion reactors will have to be regulated in almost exactly the same way as fission reactors because they are nuclear sites, with nuclear waste, and proliferation concerns.

- there is lot's of pre processing of the fuel to breed the Tritium in a molten salt blanket that surrounds the reactor and separating from the salt and then feeding it into the chamber

- there is plenty of fission and fusion fuel. Yes, there is more hydrogen around.

- tritium is used in nuclear weapons as a booster, to dramatically lower the amount of necessary fissile material - each fusion reactor is a fast neutron source, which means it can be used to make weapons grade materials. Conveniently, it has a breeding blanket for tritium, in which other fertile fuels can be place to make weapons material: proliferation concerns are a real problem for fusion

Since the reactors would ostensibly be continuously operating, the danger is the same. 10+ year half life is about as dangerous as 10000 years because you are always generating the waste.

The materials listed on the Wikipedia page and used by the Russians are not practical for large scale use. It's simply too dangerous to have that much weapons grade material or bone seeking material out in the wild. Some isotopes are better than others, and I expect there will be strides using specifically generated isotopes that are not weapons grade, are not bone-seekers, and have much short half lives (decade not 80+ years), and have beta decay.

The most convenient decay source is Plutonium-238 because it does not produce any gammas during the decay which would require lots and lots of shielding to protect people. It has long half life of 87 years so a reduction in power of roughly 1% per year. However, it's weapons material - not okay for wide use. This cannot be overstated. Making nuclear weapons today is very easy when you have the requisite materials (Ted Taylor of Los Alamos used to say it would take 3 guys a few months starting from scratch). With today's off the shelf timing systems, explosives, and manufacturing, it could be even faster.

Next up is Strontium, but that is quite dangerous due to human uptake in the bones. And there's polonium - very poisonous and too short a half life to be used.

I have heard from a friend in the business of a new concept that generates desirable isotopes specifically for decay heat sources in a reactor in an encapsulated form which gets rid of any weapons material or processing of radioactive material.

https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

That's right. You have to have a society with enough moral fiber that it self-polices and restrains itself almost down to the individual level.