Re: UDA last question (was UDA step 9 10).
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
Re: UDA last question (was UDA step 9 10).
Questions 1) and 1a) have been answered in this article: http://xxx.lanl.gov/abs/math-ph/0008018 Saibal Joel wrote: Bruno and fellow Everythingers... Sorry I've been disconnected for a while. I think Bruno's last message has really helped me to understand the Universal Dovetailer. Some of those computations will generate the 3-states corresponding to my preparing coffe 1-state. Because we accept comp. Now if I prepare a cup of coffee, my brain will go through a sequence of states (third person describable computational state, at the right level of description of myself). and I have pick one of those state---like in a duplication experiment). So the UD generates that state eventually (by going through a computation which emulates my doing or dreaming of doing that cup of coffe). So the Universal Dovetailer simply enumerates all possible states for me. (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. 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. But I am left with one nagging question: 1) Where is Time? 1a) What governs the trajectory of one's awareness through all his/her possible states? 1b) What defines the current state? 1c) How do I get from one state to another? 1d) Isn't this awareness, and its motion path necessarily outside those states and the Universal Dovetailer? 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. Can we really assume UD* exists? Doesn't it take Time to execute UD? Joel
Re: First, Third Person and Continuum
George Levy wrote: (complete message below) This illustrates the difference in the observations. Observing a spark with no detonation has a probability of 0.25 for a third person observer but 0.33 for a first person observer. I agree, at least intuitively, with your reasoning. But as you perhaps remember Jacques Mallah trapped me in some intuitive probability reasoning, and that motivated me more for my arithmetical translation. Unfortunately this has led only to the definition of the particular case of probability one. Still, it is striking that such probability has some important quantum features. Most of the time I agree with your reasoning, although I cannot say I am sure (but then I am sure of nothing!). Some of your dream comments are very nice, but I am very far of being able to ask the sound machine (through G or G*) what she thinks about that. But it is interesting having different approach leading to similar propositions. The spark itself is neither a first nor third person event. It is in-between. But this, I'm not sure I understand. Could you elaborate a little bit? Is there a relationship with the first *plural* person, which makes possible some intermediaries between the 1 and 3 person? Bruno Original message: In my opinion, the concept of first person and third person perspective is really a special case of a continuum. A first person observation of an event occurs when the event is 100% coupled with the continued existence of the observer. A third person observation of an event occurs when the coupling between the event and the observer's existence is 0%. A continuum of possibilities exists between the two. In Tegmark suicide experiment for example, the observation of the very preliminary phase of the experiment is third person. The observation of the non-explosion of the pack of dynamite is first person. Modifying that experiment slightly, let's say that the detonation of the deadly explosive is intended if a quantum coin lands tail. Let's say the the mechanism operates in two steps in rapid non-observable succession with the following probabilities:. 1) A 50% chance p1 that the electrical circuit fires, which is a function of the outcome states of the coin. If or when the circuit fires it generates a visible spark intended to trigger the explosive. 2) A 50% chance p2 that the chemical responds to the spark and detonates. (because it is (quantum?) wet for example) Here is the Third Person Perspective: Coin Head - Probability = (1-p1) = 0.50 Coin Tail = Spark = Non Detonation; Probability = (1-p1)(1-p2) = 0.25 Coin Tail = Spark = Detonation; Probability = (1-p1)p2 = 0.25 The third person probability of live outcome is (1-p1) + (1-p1)(1-p2) = 0.75 The First Person Perspective is obtained by normalizing the third person probabilities such that the sum of the live outcomes equals 1. Coin Head = Probability = (1-p1)/((1-p1) + (1-p1)(1-p2)) = 0.50/0.75 = 0.67 Coin Tail = Spark = Non Detonation; Probability = (1-p1)(1-p2)/((1-p1) + (1-p1)(1-p2)) = 0.33 Coin Tail = Spark = Detonation; Probability = 0.0 This illustrates the difference in the observations. Observing a spark with no detonation has a probability of 0.25 for a third person observer but 0.33 for a first person observer. The spark itself is neither a first nor third person event. It is in-between.
