Bruno Marchal wrote: > On 21 Apr 2009, at 18:59, Brent Meeker wrote: > >> The question was whether information was enough, or whether something >> else is needed for consciousness. I think that sequence is needed, >> which we experience as the passage of time. When you speak of >> computations "going from A to B" do you suppose that this provides the >> sequence? >> > > Not really. Subjective time, be it first person or first person plural > (and thus "physical") relies on all computations made by the UD, and > the taking into account it is "self-referential". > > > > > >> In other words are the states of consciousness necessarily >> computed in the same order >> > > Your first person next instant depends on an infinity of computations > made by the UD. The time step of the UD is relevant, because it > determines the whole UD structure, but it is not related in any direct > way with "time". We can conjecture than the more our substitution is > low, the more *time* looks like a computation being independent of us: > so relation of order can be made through indiscernible computation > equivalence class. I mean there are relation between states of > consciousness and computational history, but our consciousness > evolution is not related directly to one computational sequence. > > > >> as they are experienced or is the order >> something intrinsic to the information in the states (i.e. like >> Stathis'es observer moments which can be shuffled into any order >> without >> changing the experience they instantiate). >> > > Consciousness is related to the sheaf of computations going through > that states. A computational state is a state of a computing > (mathematical) machine when doing a computation. The machine has to be > "runned" or "executed" relatively to a universal machine. You need the > Peano or Robinson axiom to define such states and sequences of states. > You can shuffled them if you want, and somehow the UD does shuffle > them by its dovetailing procedure, but this will not change the > arithmetical facts that those states belong or not too such or such > computational histories.
I understand that the UD computes all different histories so they are interleaved. But each particular computation consists of an ordered set of states. These states can belong to more than one sequence of conscious experience. But the question is whether the order of the states in the computation is always the same as their order in any sequence of conscious experience in which they appear? For example, if there is a computation of states A, B, and C then is that a possible sequence in consciousness? In general there will be another, different computation that computes the states in the order A, C, B, so is that too a possible sequence in consciousness? Or is the experienced sequence in consciousness the same - determined by some intrinsic to the states? > And consciousness relies on those > computational facts (and information play important role there, but > not up to identify consciousness and information. (I think > consciousness is more a filtering of information, somehow). > > > > >> A related question in my mind has to do with reversibility. >> Computations in general are not reversible: Turing machines erase >> symbols. You can't infer the factors from the product. But QM >> (without >> collapse) is unitary and reversible in principle (though not in >> practice >> because of statistical and light-speed reasons). So my question is, >> are >> the computations of the UD reversible? >> > > I have still a residual doubt that a quantum computer makes sense > mathematically, but if that exists, then there exist a reversible > universal dovetailing. > > I don't understand that remark. Universal dovetailing is a completely abstract mathematical construct. It exists in Platonia. So how can the existence of a reversible (i.e. information preserving) UD depend on quantum computers? Brent > > > >> >>> and thus you have to take into >>> account the infinitely many universal number relations transforming A >>> into B. Most of them are indiscernible by "you" because they differ >>> below "your" substitution level. >>> >>> >> Does the UD have to complete the infinitely many computations from A >> to >> B, i.e. we must think of these computations as being complete in >> Plationia? >> > > Yes. Our first person expectations relies on the whole completion of > the UD, due to the non awareness of the dovetailing delay. But it is > easier to describe the working of the UD by a program executed in > time, than by an infinite set of arithmetical relations already true > in "Platonia". > > If you accept comp, you accept that your "brain state" is accessed an > infinity of times by the UD through an infinity of computations. The > world you are observing is a sort of mean of all those computations, > from your point of view. But the "running of the UD" is just a > picturesque way to describe an infinite set of arithmetical relations. > From inside it is just a logical consequence that it looks analytical > and physical. Obvioulsy a lot of work has to be done to see if all > this will lead to a refutation of comp, or to a "theory of everything". > > Bruno > > > > >>> (*) >>> - Richard Epstein and Walter Carnielli, Computability, computable >>> Functions, Logic, and the Foundations of Mathematics, Wadsworth & >>> Brooks/Cole Mathematics series, Pacific Grove, California, 1989. >>> - Boolos, Burgess and Jeffrey, Computability and Logic, Cambridge >>> University Press, Fourth edition, 2002. >>> >>> Bruno >>> >>> http://iridia.ulb.ac.be/~marchal/ >>> >>> >>> >>> >>> >>> >> > > http://iridia.ulb.ac.be/~marchal/ > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.com To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---