Levels of global catastrophes: from mild to extinction
It is important to make a bridge between existential risks and other possible risks. If we say that existential risks are infinitely more important than other risks, we put them out of scope of policymakers (as they can’t work with infinities). We could reach them if we show x-risks as extreme cases of smaller risks. It could be done for most risks (with AI and accelerator's catastrophes are notable exceptions).
Smaller catastrophes play complex role in estimating probability of x-risks. A chain of smaller catastrophes may result in extinction, but one small catastrophe could postpone bigger risks (but it is not good solution). The following table presents different levels of global catastrophes depending of their size. Numbers are mostly arbitrary and are more like placeholders for future updates.
http://immortality-roadmap.com/degradlev.pdf
2nd level probably needs more analysis-- I don't think it will look very much like the middle ages because so much will be left from the previous civilization. Even just having a lot of good stainless steel knives isn't nothing, and more generally, there's going to be a lot of refined metal around.
People might well remember crop rotation and sterilizing the drinking water.
Can anyone recommend a serious look at the question of what would remain and what would be likely to get rebuilt fairly quickly?
Yes, middle ages is more about society "style". The main economy may be scavenging, which is very unproductive and prevent to return to manufacturing economy, as scavenging will give high quality objects for hundred of years. As a result, the skills for manufacturing will be lost. Also a lot of weaponry will remain including knifes and guns (and even nukes), which may result in Long War or Somali-style world (I think that these notations are self evident). Such Long War in scavengers world will mean very long process of degradation and population... (read more)