I noticed that recently I wrote several comments of the form "UDT can be seen as a step towards solving X" and thought it might be a good idea to list in one place all of the problems that helped motivate UDT1 (not including problems that came up subsequent to that post).
- decision making for minds that can copy themselves
- Doomsday Argument
- Sleeping Beauty
- Absent-Minded Driver
- Presumptuous Philosopher
- anthropic reasoning for non-sentient AIs
- Simulation Argument
- indexical uncertainty in general
- wireheading/Cartesianism (how to formulate something like AIXI that cares about an external world instead of just its sensory inputs)
- How to make decisions if all possible worlds exist? (a la Tegmark or Schmidhuber, or just in the MWI)
- Quantum Immortality/Suicide
- Logical Uncertainty (how to formulate something like Godel machine that can make reasonable decisions involving P=NP)
- uncertainty about hypercomputation (how to avoid assuming we must be living in a computable universe)
- What are probabilities?
- What are decisions and what kind of consequences should be considered when making decisions?
- Newcomb's Problem
- Smoking Lesion
- Prisoner's Dilemma
- Counterfactual Mugging
- FAI
This doesn't seem to fit. There isn't anything about Quantum Immortality that requires UDT (except in as much as any decision requires at least some kind of decision theory). The difficulty (and common confusion) is around translating primitive preference-intuitions into preference-beliefs about wavefunctions or branches. Once the values are given, both CDT and EDT will just result in the same decision that UDT would make (unless the specific decision also combines one of the other issues UDT is required for.)
I think UDT makes it possible to understand what decisions are, and how wavefunctions can depend on one's decisions. Before I came up UDT ideas, this was really unclear to me, and I had considered some other decision theory approaches where Quantum Immortality was sort of baked in. For example I had the idea that the wavefunction couldn't be changed, but when you make decisions, you're choosing which branch of the wavefunction your consciousness continues into.
Is there a post on the relative strengths/weaknesses of UDT and TDT? I've searched but haven't found one.