I have been recently asking around whether someone has compiled how much money is going into different ways of mitigating GCBRs, so this is quite relevant! Do you have estimates of the current EA (or otherwise) spending in these or similar buckets?

1. Prevention: AI misuse, DNA synthesis screening, etc
2. Suppression: Pathogen-agnostic early warning, planning for rapid response lockdowns, etc
3. Containment: UV systems, P4E stockpiling, plans for keeping vital workers onsite, backup plans for providing food, energy and water non-industrially with low human contact, etc
4. Medical countermeasures: Platform technologies for medical countermeasures, etc
5. Detection for stealth pandemics: Different pathogen-agnostic early warning?

I think this is a very valuable project.

But this is still a combination of two questions, the latter of which longtermists have never, to my knowledge, considered probabilistically:^[3]

• What is the probability that the event kills all living humans?
• What effect does the event otherwise have on the probability that we eventually reach an interstellar/existentially secure state, ^[4] given the possibility of multiple civilisational collapses and ‘reboots’? (where the first reboot is the second civilisation)

3^{^}
The closest thing I know to such an attempt is Luisa Rodriguez’s post What is the likelihood that civilizational collapse would cause technological stagnation? (outdated research), in which she gives some specific probabilities of the chance of a preagricultural civilisation recovering industry based on a grid of extinction rates and scenarios which, after researching the subject, she found reasonably plausible. But this relates only to a single instance of trying to do this (on my reading, specifically the first time, since she imagines the North Antelope Rochelle Coal Mine still having reserves), and only progresses us approximately as far as early 19th century England. Also, per the title’s addendum, she now considers the conclusion too optimistic, but doesn’t feel comfortable giving a quantified update.

I also have not seen analyses of multiple reboots. But in terms of recovery from one loss of civilization, What We Owe the Future touches on it some. Also, my original cost-effectiveness analysis for the long-term future for nuclear war explicitly modeled recovery from collapse. However, then I realized that there were other mechanisms to long-term future impact, such as making global totalitarianism more likely or resulting in worse values in AGI, so I moved to reduction in long-term future value associated with nuclear war or other catastrophes. I like that you are breaking this up into more terms and more reboots, because I think that will result in more accurate modeling.

Thanks for mentioning resilient foods! It is true that more food storage would give more time to scale up resilient foods. Stored food could be particularly valuable for some countries in loss of trade scenarios. Some have suggested that getting the World Trade Organization to change its rules would result in more food storage automatically. Still, I think the priority now is spending a few hundred million dollars total on resilient foods to research, pilot, and plan for them. If we extend your proposal for 20 years and for the world, then you are up to ~$1 trillion. I think this is significantly less likely to happen and lower cost effectiveness than resilient foods.

I love the cumulative probability graph!

There is a little probability mass on things which are a reasonable fraction of the great or hellish futures — mostly corresponding to worlds in which the lightcone is divided in some way

• Trade means that the probability of such outcomes isn’t so high, and I’ll set them aside for now; however, I think that this would be a natural place to extend this analysis

Let's say the positive side of your graph has a logarithmic horizontal axis. I think there would be some probability mass that we have technological stagnation and population reductions, though the cumulative number of lives would be much larger than alive today. Then there would be some mass on maintaining something like 10 billion people for a billion years (no AI, staying on earth either due to choice or technical reasons). Then there would be another high slope region of AI doing a Dyson swarm, but either because of technical reasons or high discount rate, not going to other stars. Then there would be another high slope region where AI settles the galaxy, but again either because of technical reasons or discount rate, not going to other galaxies. Then there would be settling many galaxies. Then 30 orders of magnitude to the right, there could be another high slope region corresponding to aestivation. And there could be more intermediate states corresponding to various scales of space settlement of biological humans (and as you point out, different behaviors in different fractions of the space that can be settled). Are you are saying that if we have good reflective governance, we will have zero discount rate, so we will just do aestivation if that is optimal? Still, I think there could be technical barriers at various stages. But then would you argue that with good reflective governance we should be able to reach a high percent of the technically achievable value?

I think the reviewer may be concluding from the above that, given no international food trade, calorie consumption would be much lower, and therefore increasing food production via new food sectors would become much more important relative to distribution. I agree with the former, but not the latter. Loss of international food trade is more of a problem of food distribution than production. If this increased thanks to new food sectors, but could not be distributed to low-income food-deficit countries (LIFDCs) due to loss of trade, there would still be many famine deaths there. Many LIFDCs are in tropical regions too, where there is a smaller decrease in crop yields during a nuclear winter (see Fig. 4 of Xia 2022).
 

Another factor is that if countries are aware of the potential of scaling up resilient foods, they would be less likely to restrict trade. Therefore, I'm thinking the outcomes might be fairly bimodal, with one scenario of resilient food production and continued trade, and another scenario of not having resilient food production and loss of trade, potentially more than just food trade, perhaps with loss of industrial civilization or worse.
 

Yet, at least ignoring anthropics, I believe there would be a probability of full recovery of 100 % (= 1 - e^(-10^9/(66*10^6))) even then, assuming:

• An exponential distribution for the time to go from i) human extinction due to such an asteroid to ii) evolving a species as capable as humans at steering the future, with mean equal to the aforementioned 66 M years.
• The above evolution could take place in the next 1 billion years during which the Earth will remain habitable.

I think this assumes a scenario where, after the asteroid that causes human extinction, the next billion years are large asteroid/comet free, which is not a good assumption.

This was very helpful! I found the diagrams particularly useful. Visible lighting design for rooms has a similar problem of uniform illumination, but it is mitigated by the fact that there is significant reflection of the light, which I presume does not apply for far UVC. 
Has there been any work on planning to relocate existing UV systems to the most critical tasks, if an extreme pandemic hit soon, of making more super PPE/UV systems?

One unpublished study by a Russian academic and a CDC researcher allegedly estimated that the cost of 1 ACH by ventilation is about $135.91 USD and by GUV is about $14.44 USD.^[131] 1DaySooner and Rethink Priorities have estimates that "The price of current systems is currently too high for at-scale deployment, though there are reasons to think the price can be lowered significantly;" they estimate that the cost of upgrading all U.S. buildings for improved indoor air quality would be about $120 billion - $420 billion.^[132] 

The units do not appear to be complete - cost of 1 ACH for how big of space? Footnote 131 requires a password. Footnote 132 says “all public buildings in the US” not “all US buildings.” If public building is defined as this, I would guess that would control less than 10% of transmission in the US.

Why is flesh weaker than diamond?

I don't think this is a fair comparison. If nature wanted skin to be harder, it can do that, for instance with scales (particularly hard in the case of turtle shells). Of course your logic explains why diamond is harder than bone. But if you want a small thing that could penetrate flesh, we already have it in the form of parasites.

One of the points in the book Strangers Drowning was that very dedicated altruists (some EAs included) live like it is war time all the time. Basically, the urgency of people dying from poverty, animals suffering, and humanity's future at risk demand the sacrifices that are typically reserved for war time. Another example is if existential risk were high, some argue that we should be on "extreme war footing" and dedicate a large portion of society's resources to reducing the risk. I'm interested in your perspective on these thoughts.

Thanks for the correction! I have fixed it and added a link (the link was in the main document, but it's good to have it in the executive summary as well).

This is a decent summary, but there are a couple corrections:

ALLFED increased paid team members, but much less than doubled (we have capacity to expand more quickly with additional funding).

We do have 17 advisory board members, but they represent 4 countries, not 9 (the 9 countries were represented by the 17 team members at the retreat).