I don’t know how much my calculations are different from yours as I hasn’t been able to comprehend how to use your formula. Can you give me an elaborate example of using it, step-by-step?
“We can’t know that it is more likely that we are in a world that hasn’t experienced nuclear war, we are however justified in believing that it is more likely that we would be in a world that hasn’t experienced nuclear war.” Sorry, but I fail to see the difference between “it is more likely that we are in a world that hasn’t experienced nuclear war” and “it is more likely that we would be in a world that hasn’t experienced nuclear war”
I think I just found a way to roughly estimate nuclear risk by using assumptions about existence of parallel worlds and that I exist in the world that hasn’t ever experienced nuclear war because this is more probable to be in such world. x is total number of worlds whare I was born. Let’s also assume that time flows at the same rate in all worlds, so in each world current year is 2022. In some worlds I, for various reasons, died. In other ones I’m still alive. Obviously, I’m more likely to be alive in worlds where there are more people. And worlds where nuclear war happened will be significantly less populated. I read that nuclear war in our world would kill 5 billions of people, out fo current 8 billion people. So, in the most generous case, post-nuclear-war world would have about 3 billions people, while worlds that avoided nuclear war would have about 8 billions of people. Now we can make inequality, x*y*3<x*(1-y)*8. y means risk of nuclear war, namely share of worlds that experienced it since my birth up to now. Total population of all post-nuclear-war worlds combined must be less than total combined population of all no-nuclear-war-worlds, as I judge that my current existence in no-nuclear-war world is evidence that there is higher chance for me to exist in no-nuclear-war world in this year. We can divide both sideds by x to get rid of it, and then solve for y. https://www.wolframalpha.com/input?i=y*3%3C%281-y%29*8 As you can see, y<8/11, or in other words, no more than 73% of all worlds (where I was born) got nuked since my birth if we assume that this inequality is true.