On Sat, Jul 23, 2011 at 8:31 PM, Stephen P. King <[email protected]>wrote:
> On 7/23/2011 3:37 PM, Jason Resch wrote: > > > > On Fri, Jul 22, 2011 at 3:54 PM, Stephen P. King <[email protected]>wrote: > >> On 7/22/2011 10:46 AM, Jason Resch wrote: >> >> >> >> On Fri, Jul 22, 2011 at 3:30 AM, Stephen P. King >> <[email protected]>wrote: >> >>> On 7/22/2011 2:11 AM, Jason Resch wrote: >>> >>> >>> >>> On Fri, Jul 22, 2011 at 12:44 AM, Stephen P. King <[email protected] >>> > wrote: >>> >>>> On 7/22/2011 1:24 AM, Jason Resch wrote: >>>> >>>>> >>>>> All the relevant parts of relativity which imply block time have been >>>>> confirmed. The above is like arguing against gravity because Newton's >>>>> theory wasn't compatible with the observations of Mercury's orbit. >>>>> >>>>> Hi Jason, >>>> >>>> Could you be more specific? Exactly which "relevant parts which imply >>>> block time have been confirmed" and how? >>> >>> >>> Special relativity, time dilation due to speed, non simultaneity of >>> events reported by observers in different reference frames, and so on. >>> >>> And to Brent's point, regarding the conflict between relativity and QM, >>> that issue is with GR, SR is not in conflict with QM. >>> >>> This paper explains it well: http://philsci-archive.pitt.edu/2408/ >>> >>> Jason >>> >>> Hi Jason, >>> >>> I will check that paper, thanks! But here is the thing about the >>> implications of relativity of simultaneity: Since it prohibits any form of >>> absolute synchronization of events, this in turn restricts how the entire >>> space-time manifold can be considered as parceled up into space-like and >>> time like regions. >>> >> >> Imagine that spacetime is a 3 dimensional instead of four dimensional. >> Now take any object's velocity through that space time, and consider a plane >> perpendicular to the direction of that velocity. The content of that plane >> is considered the "present" for that reference frame. This is more clear if >> you consider euclidean space time rather than Minkowski space. The only >> difference you need to make to convert spacetime to Euclidean is to imagine >> that every object's velocity through space time is c. *Relativity >> Visualized* is a good book which explains this view, but this site also >> explains it: http://www.relativitysimplified.com/ . It enables an >> intuitive understanding of all the strange effects like time dilation and >> length contraction. Since we see only the three dimensional "shadow" of >> objects, an object with a different velocity is rotated in space time. It >> is like having an umbrella pointed straight at the sun vs. it being tilted, >> if it is tilted its shadow becomes compressed along the direction it is >> tilted. >> >> >>> In other words, there cannot exist a single Cauchy hypersurface what acts >>> as the set of initial (or final) conditions for a GR field equation for the >>> entire universe. >>> >> >> The fact that relativity iplies a unique present for every reference frame >> is one of the main arguments for block time. How can the car driving past >> you have a present containing different real objects than yours? Presentism >> assumes the present is the set of real objects at a given period of time, >> but what is real to you now in this moment is different from what is real to >> me in the same moment if we are moving relative to each other (even if we >> are at the same location). See: >> https://secure.wikimedia.org/wikipedia/en/wiki/Rietdijk%E2%80%93Putnam_argument >> >> The paper I cited also goes on to counter objections made to that >> argument. >> >> Thanks, >> >> Jason >> >> -- >> >> Hi Jason, >> >> > Stephen, > > Thanks for your comments. I will not reply to everything you mentioned, > because I think Jesse did a good job of adressing most of the issues you > raised. > > > >> None of those papers address the concern of narratability that I am >> considering. In fact they all assume narratability. I am pointing out that >> thinking of time as a dimension has a big problem! It only works if all the >> events in time are pre-specifiable. This also involves strong determinism >> which is ruled out by QM. See >> http://plato.stanford.edu/entries/determinism-causal/#StaDetPhyThe for a >> general overview and >> tph.tuwien.ac.at/~svozil/publ/1994-calude.pdf<http://tph.tuwien.ac.at/%7Esvozil/publ/1994-calude.pdf>for >> a discussion that involves computationalism. >> > > Determinism and locality are only lost in the collapse theories. Under MWI > and similar theories, physics is local and deterministic. > > >> >> The idea that time is a dimension assumes that the events making up >> the points of the dimension are not only isomorphic to the positive Reals >> but also somehow can freely borrow the well order of the reals. >> > > Imagine space time as an apple. Now I ask you the question "Which seed > comes first?" There is no objective answer, the seed that comes first > depends entirely on the angle at which you approach the apple. The same is > true of events in space time, there conclusion of which event occurred first > depends entirely on the angle at which one is travelling through space > time. Time, under Euclidean relativity is exactly like any spatial > dimension, the reason it seems different from the other dimensions (we can't > change direction through it, go backwards, change our velocity through it) > is because there is a physical law that all objects must always travel at > the speed of light. The dimension of time is merely the one parallel to the > observer's direction at the speed of light. This is why two objects in > relative motion to each other have slightly different interpretations of > what the dimension of time is. It is why in Feynman diagrams, one can > rotate or swap dimensions of space or time and the physical interaction > remains entirely possible. Since length contraction occurs in the dimension > of time, from the perspective of an observer their dimension of time is > 0-length (this is intuitive because if everything has to move at c one > cannot speed up or slow down to travel freely through the dimension of > time). > > > >> Please do not think that I am trying to knock Special or General >> Relativity, they both represent time in terms of local readings of clocks >> and therefore bypass the question that I am considering. The block universe >> idea assumes a unique and global ordering of events, the actual math of SR >> and GR do not! >> > > In the context of the everything, there exist an infinite number of > different block universes, and an infinite number of them contain you as you > exist in this moment. Just as you can be recreated (and brought back to > life) in a different time or place, using different material, you may also > be "recreated" in these other universes. Thus from one second to the next, > you can travel between these universes, between vast times, between vast > distances. You can never be sure where you are or where you will be. This > is the reason for the apparent indeterminism in physics. For details, see > this paper, which explains how the simple theory that our universe is > infinitely large, leads directly to the weidness of quantum mechanics: > http://arxiv.org/abs/1008.1066 > > Jason > > -- > > Hi Jason, > > Please see my last response to Jesse. > > I like that > Aguirre<http://arxiv.org/find/quant-ph/1/au:+Aguirre_A/0/1/0/all/0/1> > , Tegmark <http://arxiv.org/find/quant-ph/1/au:+Tegmark_M/0/1/0/all/0/1>and > Layzer<http://arxiv.org/find/quant-ph/1/au:+Layzer_D/0/1/0/all/0/1>paper ! I > only take exception to its tacit assumption of spacetime > substantivalism. > http://plato.stanford.edu/entries/spacetime-holearg/#PriSpaSub It assumes > an infinite number of spacetimes instead of just one and so does not address > the problem that I am trying to point out. > I am arguing that spacetime is not a substance what we are somehow > embedded in but something that emerges from the interactions of many QM > systems; it is what their observables have in common. I take QM to be a > theory of observers and GR is a theory of how observations are organized. A > theory is a explanatory model and its concepts should never be considered as > objectively existing 'things'. If there is a one-to-one correlation between > the entities of a theory and entities within our phenomenal experience then > that is the hallmark of a good theory, but the theory is never the phenomena > itself. > > Onward! > If you want to formulate block time without reifying spacetime, then just consider block time a collection of events separated by certain distances and directions from eachother. You may be right that ultimately this is all related to a theory of observation, and I think I can understand what you mean by relativity explaining the organization of these events/observations. In any case, a block universe seems to be a simpler theory than that of one in which objects become real and become unreal continuously, and it is consistent with observations. There is no scientific justification for presentism that I am aware of. Jason -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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