The issue of the subjective immortality paradox implied by the various levels of the multiverse1 has been occupying my mind a lot. To summarize what I mean, the fundamental issue I have with these models is that they seem to strip away any semblance of free will, agency, purpose, or indeed, reason to do anything at all. After all, no matter what I do, there exist branching futures of myself that will experience everything possible, without my actions really being necessary.2
Why, then, set out to achieve anything at all, if you could simply kill yourself whenever random fluctuations and chaos theory fail to conspire to give you what you want? Or, more disturbingly, consider what would happen when you do attempt dying: Random events would never cease to keep you conscious, somehow, forcibly - long after everything you could possibly care about has vanished. Mathematically, the various multiverse models might make perfect sense, but philosophically, they undermine any possible purpose or axiom of any possible thought you could derive from it. It seems to me like something must be missing from the picture.
One of the ways to deal with this conflict is, I think, to reimagine the concept of “existence”. We think of things as either existing or not. But what if existence itself is a sort of fundamental resource? Could some branches of the wave function, say, somehow have more “existence” than others? And furthermore, could the existence resource itself be somehow finite or quantized, leaving us with a “minimum threshold” of existence, beynd which things are simply too unlikely to exist at all, period? Like some sort of great existential censor protecting us from cosmic absurdities.
The pleasant upshot of this idea is that it becomes in our interest of survival to try and maximize our existence in a very literal sense - that is, to say, minimizing our reliance on random events to keep us alive. In this sort of reality, agents would be expected to have a strong sense of self-determinism, and adaptability to the environment.
As interesting as this idea is, not only am I unsure how mathematically consistent it is, I’m also not sure how testable it is. That being said, it should be possible to set bounds on how unlikely things have to be to cease existing, with experimental observations of extremely unlikely events.3 Precise measurements of certain quantum mechanical observations, for example, can be used to verify the influence of extremely unlikely interactions - without having to wait long amounts of time. That being said, the number of measurements needed to reduce the uncertainty in the measured figure to the required degree might balloon in a manner proportional to the probabilistic influence being measured. I haven’t done the math here. Otherwise, we could maybe design an experiment to somehow “amplify” the influence of such very subtle possibilities? Although, if on experiment entangles such obscure worlds with a majority of “benign” worlds in a way significant enough to be macroscopically visible, the experiment itself would arguably be enhancing the “existence” level of these obscure worlds. Maybe, then, this type of experiment is fundamentally impossible to conduct? Could the precise measurements4 of interactions itself cause those interactions to take place?
In any case, regardless of its scientific value, I think I prefer a model like this over going to bed at night knowing I’ll witness every manner of possible cosmic horror within my coming infinite lifetime.
It’s a common misconception to hinge this issue on the Everett many-worlds interpretation of quantum mechanics. But a lot of other models also imply a multiverse, including almost any model that assumes a spatially infinite universe, cosmic inflation, or the mathematical universe hypothesis.↩
Although one has to be careful in arguing this sort of extreme to avoid the paradoxes implied by self-sampling, including such absurdities as Boltzmann brains, whole-brain simulations, or the Doomsday argument.↩
Arguably, the nonexistence of Boltzmann brains sets a lower bound on the probability censor - but that assumes our models of the universe are accurate and predict Boltzmann brains.↩
Although “measurement” does not assume the existence of scientists. Every macroscopically observable chemical phenomenon that depends on the level of precisions in an observable way constitutes a measurement - whether humans are around to observe it or not.↩