Joel Dobrzelewski wrote:

>So the Universal Dovetailer simply enumerates all possible states for "me". Yes. I prefer to say it generates all computations going through that states(°). Bennett has introduced a nice notion of depth from string, which is grosso modo the runtime to produce it. It is still possible (even probable) that "me" is deep and "you" are deep so that the occurence in UD* of you and me can be taken as evidence that we do share a "long" computation. (°) I see Hal Finney says the same thing. >(Whatever "me" is, is unimportant). And somehow, these states are joined by >their similarity to one another, which allows (virtual) motion from one >state to the next. I think the relation of similarity, or proximity bears on the computations/histories/dreams. But you are correct. The only way to keep sharing the same deep computation, and thus sharing our domain of undeterminacy, is that the computation is "linear in our common ignorance". This will multiply both of us, in some conservative way, and in extremely "explosive" way. I guess the first person *plural* has it origin in such self multiplication sharing. >So, if I am currently sitting in the state of "sitting at my desk", I have >several realities branching off from this one where in the next moments I am >"rising from my chair", or "still sitting at my desk", or "petting a white >rabbit". In case comp is true, I'm afraid necessarily so. Note that the existence of QM gives confirming evidence that there is some branching. And perhaps you can guess that comp predicts that any machine looking at her neighborood sufficiently closely, i.e. below her level of substitution will discover some "observable weirdness" and other continua of parallel computations ... Note that histories can be considered as fusing by difference amnesy. I really hope to succeed in "rediscovering" the quantum computer through "machine's introspection". >But I am left with one nagging question. I really hope so Joel. My strongest goal with UDA is to show that computationalism or mechanism does not solve *per se* the mind body problem. Quite the contrary. "Before UDA" you can believe there is only a "consciousness problem", "after UDA" you got a "body" problem too. Understanding comp consists in understanding that matter/space /time is necessarily not obvious and must be recovered from the space of all computations as seen as some internal points of views. I told you that my UD or your MUCA or Schmidhuber's Great Programmer, ... are not the solution, there are only steps toward a mathematical *formulation* of the problem. Of course the formulation gives insight, (the reversal)... and that's nothing compare to the arithmetisation of that formulation, weird quantum logics, but that's technical ... (if you know modal logic search for LASE in the archive). >1) Where is Time? Time is *the* first person concept "par excellence". It is linked with intuition, consciousness, but also construction, and truth. The arithmetical translation of UDA let me hope that time is captured by the modal logic known in the literature as S4Grz. >1a) What governs the trajectory of one's awareness through all his/her >possible states? The geometry generated by the notion of proximity on the (maximal ?) consistent extensions (our alternative "completed" futures). Or if you prefer, what governs the possible trajectory of awaraness is Schroedinger Equation. Our problem: extract it from the geometry above. >1c) How do I get from one state to another? You 3-don't. You 1-do. This must be related to the geometry above. >1d) Isn't this "awareness", and its motion path necessarily "outside" those >states and the Universal Dovetailer? No. But perhaps you are close. A bizare thing is that if someone look at a portion of a representation of UD*, he can say there is, in some sense, no awareness possible in that portion. And this remains true for all finite portions of UD*. The "meaning" appears only when the whole UD* is considered. This is coherent with the fact that the neighborhood of "first person state" are defined on that limit. An image is that each instant, each observer moment perhaps, is defined by a "trip" from the base of the cone (UD*) to the (non existing) top, at infinite speed, just because we cannot be aware of the delays, nor of any initial represention. >Since I am into cellular automata, I always assumed that time is implemented >naturally... by the automaton... from one tick to the next - just like a >movie. That's the integers sequence. No? >Can we really assume UD* exists? Unless you are finitist you can realise that with comp you cannot escape its existence. You get UD* once you accept the existence of *all* natural numbers, and all their describable relations. But no problem without changing your mind. Abandoning comp by abandoning arithmetical platonisme is a way like another :-) >Doesn't it take Time to execute UD? No. Only a concrete UD, concrete relatively to "your" most probable histories, will take enormous time. But tell me, if you postulate that time, how could we explain it. What would that time be, and where would it come from? You tell me you don't need time or space with Your MUCA, isn't? In Platonia it takes neither millimeters nor seconds. Arithmetical relation are not "temporal", still less (with Occam) if we can justify or just identifies the discourses on the "temporal" by the "soud introspecting machines". Bruno http://iridia.ulb.ac.be/~marchal