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Memammal

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  1. Just as a side note: the wording on the picture may give a somewhat fallacious impression, but philosophically speaking it is still regarded as a significant differentiating factor between presentism and eternalism. Less so than with the future, but still. I can elaborate on this, but let us leave it for "now".

     

    If double time exists, then time is not a line anymore, but a surface.

    Furthermore, if the past is not "frozen", it becomes something very similar to the future: something that can change (randomly).

    In such a way that even if time would "flow backwards" (to be read as a U-turn of the observer), the observer would observe nothing very special happening, only usual "flow" (to be read "usual motion in spacetime").

    I know it is wild speculation, but that would make time and space a little more equal. Not to say that in principle, triple time would be needed. Each time for each spatial dimension.

     

    Refer to my post in the other thread "3D Space, relativity and presentism".

     

    Michel, I don't follow your reasoning as to why a line will become a surface with "double time". Your comments w.r.t. the past not being frozen seem like (valid) criticism against presentism. And as for your third paragraph, again sorry, but I don't follow.

     

    I think we need to have a proper chat about time. This thread seems to be appropriate as we have already raised it various times. Refer to among others:

    Post #195

    Post #201

    In the last post (#201), I gave various references that deal with the concept of time. This one needs careful attention: Physical time

     

    PS. Or do you prefer to rather discuss TIME in the thread "3D Space, relativity and presentism", Tim, as you already started with it there?

  2. ^ Not sure how many of you have seen this:-

     

    There are things that are funny “because they are true,” and then there are things that are sort of funny, but would be funnier if they weren’t so very true. A case in point, video maker Matt Orfalea found an old copy of the 1990s puppet sitcom Dinosaurs. You don’t need to know the 1990s show or have liked it if you do, to watch the clip below. Comparing Donald Trump’s interviews and candidacy seem to resemble, like a Twilight Zone episode, the triceratops bad guy on the 1990s sitcom—Mr. B.P. Richfield.

    Trump runs for President. Richfield runs for “Elder.” Trump is crass and sexist and mean. Just saying. Richfield says that all of the dinosaurs problems are caused by the “four-leggers” who have been immigrating from over by the swamp. You get the picture.

    Enjoy!

    http://www.dailykos.com/story/2016/10/25/1586843/-Somebody-realized-that-Donald-Trump-is-actually-a-dinosaur-character-from-1990s-and-it-is-uncanny
    Direct link to YouTube video:

  3. Presentism according to Wikipedia:

     

     

    Philosophical presentism is the view that neither the future nor the past exist. In some versions of presentism, this view is extended to timeless objects or ideas such as numbers. According to presentism, events and entities that are wholly past or wholly future do not exist at all. Presentism contrasts with eternalism and the growing block theory of time which holds the past events [sNIP] really do exist, although not in the present. Eternalism extends to future events as well.

    [sNIP]

    In modern theory of relativity, the conceptual observer is at a geometric point in both space and time at the apex of the 'light cone' which observes the events laid out in time as well as space. Different observers can disagree on whether two events at different locations occurred simultaneously depending if the observers are in relative motion (see relativity of simultaneity). This theory depends upon the idea of time as an extended thing* and has been confirmed by experiment, thus giving rise to a philosophical viewpoint known as four dimensionalism.

    * Note: "extended thing" means stretch out through space or stretch out over time. As time cannot extend over time (which seems to be at the core of different points of view in this and other threads), it obviously refers to an extension through space, i.e. a dimension thereof.

  4. The good thing is that most of us now seem to roughly agree about what "time" is (as differentiated in duration, sequence and instant); the problem seems to be more a matter of understanding how that fits in with the different models of Space / Spacetime.

     

    Yes (emphasis on most of us) * [EDIT: To be revisited] *

     

    It's already very surprising - and a nice surprise indeed - that we are much on the same page about what "time" is.

     

    Tim, I would like to revisit this at some "point in time". I have a suspicion that I might have jumped the gun with my reaction...without paying proper attention to what you stated in brackets (which I have now marked in red). This may, or may not be critical. I suspect it is. Lol...this after I agreed that most of us know what time is...

     

    For example, the picture that you posted contains the same fallacy about "presentism", as if past experiences were not real.

    Just as a side note: the wording on the picture may give a somewhat fallacious impression, but philosophically speaking it is still regarded as a significant differentiating factor between presentism and eternalism. Less so than with the future, but still. I can elaborate on this, but let us leave it for "now".

     

    I will revert and react, if needed, to the rest of your last post sometime tomorrow.

  5. Back to Tim:

     

    I managed to work my way through your post, but I sense a reluctance in you to accommodate anything that does not fit Tim's reality. I find it somewhat ironic and a bit frustrating considering the fact that you attended that lecture that explained how our brains process (real) reality for the purpose of storing it in our internal memory. I find it equally frustrating that you seemingly want to drag old paradigms out of the dark ages and present them to us (because they best fit Tim's reality), while the post-Einstein schools of thought have gone in a different direction. In any event, I want to copy a comment that I made to koti:

    We are indeed speculating and debating models without having definite answers, but we should at least be able to separate the wheat from the chaff. Science as we know is a dynamic process incorporating a multitude of different methodologies. It is definitely not a popularity contest. I think the single biggest challenge is to be able to scientifically differentiate between- and consider the merits of what seem sensible to our somewhat restricted (human and earth-bound) sense of reality, or intuition, and any paradigms that seem to be in conflict with it (in stead of frowning upon the latter).

     

    Let me comment on a few issues that you raised:

     

    As I already had debunked that misconception about presentism in the thread on 3D space and presentism, I now did it there once more, with more elaboration.

    I don't think you did. You only merged it with Tim's reality. Are you saying that time moves or that it does not move, that the now moves or that it does not move?

     

    Yes, I agree; and it's even incompatible with presentism, as I elaborated here. It's more compatible with eternalism in a 4D Spacetime, as there "time" is a kind of distance that people progress over - which brings us back to the "double time" issue that you brought up.

     

    The good thing is that most of us now seem to roughly agree about what "time" is (as differentiated in duration, sequence and instant); the problem seems to be more a matter of understanding how that fits in with the different models of Space / Spacetime.

    No, it is definitely not "more compatible with eternalism".

    Yes (emphasis on most of us) * [EDIT: To be revisited] *

     

    Yes, exactly. What you have been saying was quite clear from the start.

    Moreover, we can walk to the left or to the right, but we cannot walk back in time - it's simple as that! The "moving arrow of time" on top of "eternal time" remains an issue for the block universe...

    This is where I stopped reading the first time around. I am afraid to say that this substantiates just how little you know about the block universe model. Left, right but not back? What MOVING arrow of time? Go back a bit and read the discussion between koti, studiot and myself.

     

    In short, 4D Spacetime as [TIM's] reality can hardly escape a "double time" consisting of two very different time concepts that are equally true physical reality. But in fact, the "eternal" time distance is superfluous for physical [TIM's] reality.

    Removing that [TIM's] superfluous part we're left with 3D Space (+ the ordinary "time" concept) which doesn't have such issues. Moreover it has more explanatory power and is intuitively easier to understand [for TIM].

    Corrected above.

     

    3. https://www.quantamagazine.org/20160719-time-and-cosmology/

    At least that's about "block" vs. "presentism", citing the different opinions. apparently Smolin is also "fed up" with block, like I am now. And "blockers" are trying to explain the arrow of time. However, this is just trying to explain a problem that the model causes! Trying to fix a problem of the model isn't helping to make sense of the physics - just as repairing a broken saw doesn't cut wood. And the "growing spacetime model: "Space-time itself is growing as time passes". Sorry, but to me that's just hilarious!

    - causal set theory for predicting cosmological constant: that is suggested to be based on "block". However, at first sight, it's in fact based on GR math.

    Smolin & Co. are mostly fed-up with the future-is-set part of the block universe. Nonetheless, there were and still are attempts to replace- or improve on the block universe model (as the article alluded to). That is the nature of science. Some are more successful than others (Mordred and ajb previously pointed to some of these). The article highlights the fact that it is easier said than done to just throw out the block universe model as an accurate reflection of (Einsteinian) reality. And why do you keep on implying that the block universe model caused the (problem of the) arrow of time?

     

    - "It emerges that the feeling we have of the passing of time is nothing more than an illusion of human perception due to the asymmetry of the time axis: we can remember the past, but we cannot remember the future."

    That's again an attempt to solve a problem of the model, instead of showing how the model can help solving problems!

    Any model should attempt to best reflect nature's reality, don't you think?​

     

    - "The conclusions presented here relating to the block universe model follow directly from Einstein’s theory of general relativity":

    that's just more bunkum.

    How does it misrepresent Einstein's theories?

     

    - "It is true that there is a time dimension defined within the universe. And for an observer within the universe, objects appear to change with respect to this time axis. However, this apparent flow of time is just an illusion of human perception due to the asymmetry of the time dimension."

    Is there anyone here who found that a helpful explanation of how "eternal time" can be experienced as a measure of change?

    I explained it all on the previous page. I wanted to suggest that you need to think outside the block, but maybe that would not be entirely accurate.

     

    - there is supposedly no beginning of the universe because "The entire spacetime block is laid out as one unchanging structure."

    But then, to be consistent, neither did anyone of us have a beginning; we were never born, but instead "laid out as one unchanging structure" as well. Problem solved??

    What do you mean we were never born? What problem? Read the previous section in this thread (between koti, studio and myself).

     

    - Wheeler-DeWitt Equation : there's an issue that I don't know of, that "the rate of change of the state of the universe with respect to time is zero". No doubt that is open for different interpretations, but "block" explains it as follows: "The notion of evolution is not applicable to the universe as a whole since there is no external observer with respect to the universe, and there is no external clock that does not belong to the universe". Great. But totally unconvincing, as no "outside clock" is needed for establishing the existence of a rate.

    Refer to the inherent differences between my scenario 1 & 2 and look at that picture that I inserted above.

     

    I now think more and more of empty perimedes-like philosophical debates... and that's quite the contrary of what I intend with this discussion.

    Yes, this sums it up. What did you intend? To get a model that best describes earth-bound human (or Tim's) reality opposed to nature's reality?

     

    5. Growing block in wikipedia. Interesting additional problem brought up there: we cannot know when "now" is with that model!
    And (of course), apart of the more intuitive aspect as it's closer to Absolute Space, there is no suggestion of how the concept can be useful for better understanding physics...

    And of course, i.t.o. presentism, that is quite a significant problem not knowing when (opposed to where) the now is. Again, are we not looking for models that best describe nature's reality?

     

    Just one left: http://www.journals.uchicago.edu/doi/10.1086/392846

     

    Regretfully my institution has no subscription to that journal. Memammal, please summarize useful aspects of "block" for physics according to that article, thanks!

    Was that not the paper that I suggested that you or Michel could read as it may shed some light on Michel's insistence that there must be time within time? It is available, just Google it. I don't see why I need to. I don't have a problem with time within time.

     

    EDIT: ADD SEPERATION---------------------------------------------------------------------------------------------------------------------------------------------------------


    Does this help?

    Let me look at it again, thanks studiot.

  6. Tim, I started reading the first part of your post only to realise that we seemingly find ourselves on very different pages i.t.o. understanding the block universe model. I think you may have a misconception thereof (it seems evident from that first part of your post that I read), but maybe it is just me and the writers of all the articles that I already provided that just don't get it. I thought we were "past that point" of the discussion, but I think the main difference of opinion lies in the way we understand presentism vs eternalism..? Anyway, I will attempt to attend to your post at a later stage when I have enough time and try to dissect it in the hope that we are just misunderstanding each other.

     

    In the mean time, maybe this (admittedly very basic) picture helps to illustrate tensed (presentism) vs tenseless (eternalism) and the block universe:

     

    BlockUniverse_DaviesSketch.jpg

     

    But both please consider this.

     

    Another viewpoint is to divide the time axis in a similar manner to the mathematical definitions partitioning infinities real and potential infinities.

     

    This was where my introduction of y = x2 was leading.

    studiot, I think we find ourselves slightly more on par w.r.t. understanding the block universe model. I was expecting a next move from you, read it between your lines, so to say. When you mentioned the fishing bowl, I thought you were heading towards a spherical/circular-like hologram, i.e. where the four dimensions start curving back onto themselves, where infinity meets infinity and where events/moments end up going around in circles (i.e. we bend that ruler and the whole caboodle with it until the two ends touch each other again). That seems to be one of the candidate paradigms out there in theoretical science land and something that is not entirely implausible as it seems somewhat "natural". It may open a whole new can of worm(holes), but then it may resolve quite a few others (like the uncertainty of quantum behaviour). Don't take me seriously on this though; I am just throwing it out there...

     

    What I am seeing/understanding from your description is something similar, but without the two ends meeting up again. Your description/equation seems to enforce an exponential space enlargement. I assume something resembling a (square?) cone like figure which would enlarge from the singularity across its y axis, i.e. vertically like this illustration of Minkowski space (although this illustration depicts the narrow point as being the present, almost like my presentism illustration where the now sits at the zero on the ruler):

     

    minkowski_spacetime.gif

    Is this more or less right? I don't see a problem with an enlarging square-cone-like representation instead of the square block. The underlying principle remains more or less in tact, no? Perhaps you should rather elaborate a bit on your idea..?

     

    PS. Or are you perhaps implying the growing block universe?

  7. @ koti: Yes man, you are getting there ^_^ ...even correcting or questioning me for using a conventional (aka intuitive) terminology when describing the "unfolding (of the universe) over what we perceive as time".

     

     

    Are you saying that there was something ongoing before T0?

    Well, I am not saying that. The model implies it. That is why I extended the ruler to both -infinite and +infinite on either side of the BB @ zero. The hypothetical events/moments prior to the BB are (still) equally real.

     

     

    Actualy the BB singularity and implications of it do not sound ubelivable to me. This stuff is (hopefuly) for quantum gravity to determine and I don't have a problem with this even now before we get any answers.
    What I have a problem is with time...it is possible in my opinion that the BB singularity very well might not be "unfolding over what we perceive as time" as you stated above. I have a feeling that we are prisoners to these kinds of notions when in fact we haven't made a leap yet to grasp time in its true form. Take Newtonian space as an example and how the view of it changed with the introduction of SR and GR - I think we are still to make a similar leap concerning the concept of time.

    Nicely put. Fact of the matter is that we (or most of us) have already become accustomed to the idea of the BB, so it is not a stretch of the imagination. Still, if you think about it and in the way that the first generation must have thought about it...it is an astonishing feat. EVERYTHING in our (observable) universe was in that singularity. Nothing, zilch, was ever added. So all that "information"...past, present and future...were already pre-packaged. Our conventional way of looking at it is that it took 13.8 billion years (and counting) for it to unfold...but WHAT IF it had all existed already in the form of a block universe...and we just happened to observe it in (or interpret it as) different stages happening over "time"..? So you might as well ask (and many have) how did it all get in there, how "long" did it take for it to be assembled in the first place..?

     

    'Progress along' implies a contradiction with the block universe.

     

    Some of (the best) earlier writers in relativity discussed our perception of time at great length and also considered this relevant as it conditions our attempts to describe and model the physical phenomenon we call time.

     

    Think about a small child, who only understands right now! and a goldfish who forgets where the beginning of his bowl is by the 'time' he has circumnavigated it.

    Every now and again I mistakenly use conventional terminology in order to explain something. Fortunately there are the likes of you to correct me. Thanks and well said. One of the best ways to describe it i.m.o. is akin to what I used earlier: a moving observation or a flowing experience.

  8. But lets improve the scenario 2: rain is falling along the ruler while the observer slides from one time stamp to another. IOW, the present is the crossing event between the position of the observer and some rain drop. In this scenario, the future is not "already there", and the past is not "frozen". If you understand what I mean.

    I think I might have covered this by means of my follow-up:

    In scenario 2 [snip]... Rather think of it as a moving observation or flowing experience. The observer is experiencing a next moment (the technical term is qualia). Hence, it is our observation/experience that moves on- or through a static timeline (or through our embedded-in-spacetime lifeline). Next time you walk around the house, think of it as a moving observation from one spacetime coordinate (moment) to the next.

     

    The fact is that we are not able to observe a spacetime coordinate that sits somewhere in the "past", I mean in "our past". The only things that we can directly observe from any time stamp are very specific and depends on distance.

    -------------

    (edit) I mean, the objects that we can observe all belong to the past, but they do not represent "all the past". They are the objects that lie at a specific distance and at specific time stamp of the past. All other events that are a time stamp that does not correspond to this particular distance are not (directly) observable.

    Yes, we can not observe everything...not even in "real time"...but there is no need to; it does not mean it never "happened" or never "existed".

     

    koti wrote:

     

    Just so we are on the same page, I do not have a problem with the "capacity" of nature as to the amount of information in it. Rather I have a problem with the concept of introducing this amount of information representing future events "instantly" at the BB. This instant inctroduction of information is in my opinion inevitable in the block universe concept where past, present and future events are co-existing in some kind of continuum. Take space and the BB as an example...big bang is an ongoing process whereas the future events of time in the block concept would have to be introduced instantly unless the properties of time are not universal which is highly improbable IMO.

    Define "instantly" and no, it did not have to happen at the BB. As you correctly pointed out, the BB is ongoing. It has also been "ongoing" on the other side of what we refer to as the BB singularity (on the minus side of that ruler). I do understand that it sounds unbelievable, but consider this. Everything that is contained in the universe as we know it at present have been part and parcel of the singularity...that singularity has just been expanding and unfolding over what we perceive as "time" (i.e. the so-called 13.8 billion years)...but it was all contained within the tiniest imaginable fraction of space.

     

    I have to disagree...you're implying that time has fundamentaly different properties and is essencialy a different entity depending on what models we use to define it.

    Read Tim88's post in another thread with his overview of time. It boils down to different ways of perceiving, describing and using time (and as a side note, I don't think he mentioned Planck time). I know that in physics time is measured with a clock, but consider this quote: Time is a component quantity of various measurements used to sequence events, to compare the duration of events or the intervals between them, and to quantify rates of change of quantities in material reality or in the conscious experience (Wiki: Time). Further to this, you may want to consider this section of the same article: Physical time. There are, however, also various philosophical concepts of time and this brings us closer to this discussion: Philosophies Of Time. In this discussion you may want to think about conventional time (moving time/now) as something along the lines of presentism and the notion of a static time dimension as being associated with eternalism (many now's).

     

    I think the rest of it resolved itself, so to say?

     

    But that way opens the floodgates for all sorts of paradoxes and fallacies about time travel.

     

    Perhaps not so simple after all?

    I think he meant that the observer is naturally progressing along his lifeline, experiencing different events/moments at consecutive coordinates...not "artificially" relocating himself to other coordinates in either the past or future. Due to the fact that events are carved in stone and thus pre-existing (in said model), there can be no time travel paradoxes.

  9. @ koti: First of all, I did not mean to come across as dismissive of the "too much information". You might have a point from within a certain paradigm and by using the word "information" in its appropriate context, which was the point that studiot wanted to convey.

     

    You quoted above that time does not exist except as a concept of relative motion or events relative to the motion. We know from GR that spacetime cannot be treated independantly from matter. We know that time dilation and metric contraction are confirmed phenomena. If time doesn't exist and is just "relativity of events" then from that logic we should derive that space does not exist as well. That just doesn't stick.

    We are talking about two different kinds of time. Absolute (or conventional) time vs spacetime (i.e. as the fourth dimension in a spacetime coordinate). My references to "timeless" and the references to time in said quote refer to conventional time. With "timeless block universe" I meant the ETERNAL aspect thereof (which by implication will be "timeless").

     

    You gave an example earlier of a ruler representing time and a toy object representing a person. From that example which stated that it's not the ruler which is moving but the toy itself you derived that we are moving through time as opposed to the concept that time is flowing and we are "stationary" My question is very simple...wheres the reference point to determine what is moving and what is stationary in that context?

    The ruler represents the time coordinate part of spacetime. In scenario 1 the zero corresponded to the now. I explained that one would have to move the entire ruler (being the time dimension of spacetime) in order to move the zero/now, or for time to flow/move. By using such an analogy/model you have the advantage of (hypothetically) getting an external perspective. You should be able to understand that it does not make sense to move the ruler...in relation to what is the ruler/time moving? (The same argument that was made in the article that I referenced.)

     

    In scenario 2 I placed the toy (observer) at a hypothetical time coordinate that would correspond with our "present time" in relation to something like the BB. The ruler, or time dimension, is kept still while the toy/observer moves to the next time coordinate (the next moment/event). This can be somewhat confusing (which is probably why you were posing the question) as you may perceive this as a movement of the physical body. Rather think of it as a moving observation or flowing experience. The observer is experiencing a next moment (the technical term is qualia). Hence, it is our observation/experience that moves on- or through a static timeline (or through our embedded-in-spacetime lifeline). Next time you walk around the house, think of it as a moving observation from one spacetime coordinate (moment) to the next.

     

    I will go on a limb and state that we have absolutely no idea what the true nature of time is and were trying to invent like little children. On one hand we know how time manifests itself to us in models like GR but if we cant even be sure if time exists or not there is surely a lot more to it than what we see. Gravity in that sense is analogous, so far we only observe how it manifests itself to us but there are realy major pieces missing like why is gravity so weak compared to other forces or how it works in the planck scales. Frankly, the more I digg into theorerical physics, the more I have a feeling that we know very little...the trip is breathtaking though.

    We are indeed speculating and debating models without having definite answers, but we should at least be able to separate the wheat from the chaff. Science as we know is a dynamic process incorporating a multitude of different methodologies. It is definitely not a popularity contest. I think the single biggest challenge is to be able to scientifically differentiate between- and consider the merits of what seem sensible to our somewhat restricted (human and earth-bound) sense of reality, or intuition, and any paradigms that seem to be in conflict with it (in stead of frowning upon the latter).

     

    I just read Tim88's post in another thread that seems to give a pretty good overview of the various concepts of time. I may have to reconsider my vague usage of the terms "absolute" and "conventional" time, although it should not change the essence of the narrative.

  10. It is a fact that the individual events as we measure them in QM cannot be predicted. We even know that there are no local causes determining what we will measure. So there is not not left much room for determinism in QM, except Bohm.

     

    In chaos theory events are determined, and can in principle be predicted, however we quickly loose practical predictability, because we should know the beginning conditions in a precision we are not capable of.

    Are you implying determinism = predictability and indeterminism = uncertainty? Could a seemingly uncertain (or seemingly random) outcome not be deterministic?

     

    * EDIT * [i am deleting rest of this post as it has already been dealt with]

  11. Yes indeed this thread got side tracked, and it risks to get sidetracked further. As you here are replying to my comment in the thread about presentism, I'll reply there.

    Post # 166 & 167 of this thread refer.

    ^ Read together with this quote from my post # 175:

    • Special relativity eliminates absolute time (although Gödel and others suspect absolute time may be valid for some forms of general relativity)[16]...
    • [This may be an important source as it could link back to quote from Michel: Something like a "double time" is needed in this concept too.]​

    PS. @ koti: you earlier asked about books re the block universe model. I have since remembered a reference to such a book; something that I actually mentioned in another thread that you also participated in. Here is a MIT review of it: “Objective Becoming” by Brad Skow. Here is a comment by one of the readers of that column that may be relevant:

    On page 155 of his book on the special and general theories Einstein makes it clear that in general relativity, space-time no longer can claim an existence independent of matter. On page 141 he said, “Our concepts of space and time must be preceded by the concept of the material object.” Almost everyone seems to have missed this. Time does not exist, therefore, except as a concept of relative motion or events relative to the motion of material objects, which we have chosen the spin and orbit of Earth. Time is thus the relativity of events. And events are separate realities.

    True. I did introduce the information subject earlier. I thought it will be relevant when trying to cope with the oroginal block concept where the future events are "a done deal" What immediately struck me is how could nature introduce that at T-0 and it also correlates to Hawking's work on black holes information paradox. For what its worth, I am not concerned with the available "space for all the information" I am concerned with nature introducing those future "done deal events" instantly at T-0.

    As I alluded to earlier, where/when will T-0 be in this "timeless" block universe?. Hrvoje Nikolić argued that a block time model solves the black hole information paradox. [Nikolic H. (2009). "Resolving the black-hole information paradox by treating time on an equal footing with space". Phys. Lett. B 678 (2): 218]

  12. I did not introduce 'information' here in the first place and there are implications using this concept.

    Not in the least the relationship between information and evolution and the difficulty that people experience coming to terms with the idea that informational complexity can arise from purely random processes.

     

    Also information is something that we see or can extract from the configuration of a system, which need 'know' nothing about this information itself.

    Point taken. The use of "information" was introduced earlier by koti in reference to whether there is enough "space for all the information" to which you responded with your explanation w.r.t. lossless. It was in that sense that I continued to use it, but you are right in referring to its other connotations.

    As a side note...something that I forgot to respond to:

     

    In my opinion, Wikipedia is hardly of more value for philosophical citations than this thread itself. Moreover, in this thread we are comparing disagreeing explanatory views of relativistic physics with each other - and not classical physics with relativistic physics.

    I provided those quotes in attempt to substantiate the pivotal role that Einstein played in changing our perception away from absolute time and absolute space whilst also reaffirming the lesser status of the latter, even within the context of Newtonian mechanics.

     

    ​Let us not get side-tracked by this side note though.

  13. One of the ways in which we create lossless compression in movies is to only record changes from frame to frame (Note the cinematographic use of the word frame)

    This is pretty relevant to the block universe model. First and foremost the concept of lossless. It is a technical term mostly used in audio/video formats. If one records in a lossy format some (unnecessary...which could be either empty, almost empty or duplicated) information is discarded in the process. When our brains perceive said lossy information, it processes it and reassembles it by means of for example psychoacoustics in the case of audio. Let me quote:

    ...in many problems in acoustics, such as for audio processing, it is advantageous to take into account not just the mechanics of the environment, but also the fact that both the ear and the brain are involved in a person’s listening experience. The inner ear, for example, does significant signal processing in converting sound waveforms into neural stimuli, so certain differences between waveforms may be imperceptible. Data compression techniques, such as MP3, make use of this fact... Another effect of the ear's nonlinear response is that sounds that are close in frequency produce phantom beat notes, or intermodulation distortion products. The term "psychoacoustics" also arises in discussions about cognitive psychology and the effects that personal expectations, prejudices, and predispositions may have on listeners' relative evaluations and comparisons of sonic aesthetics and acuity and on listeners' varying determinations about the relative qualities of various musical instruments and performers. The expression that one "hears what one wants (or expects) to hear" may pertain in such discussions.

     

    I am using this in order to illustrate how our brains sometimes fill in (or compensate for-) our perception of reality.

     

    Lossless refers to native information/reality. Nothing gets changed, lost or replaced. There can be no vagueness in perception. In studiot's analogy you can compare each frame with an "event" at a new point in spacetime where new lossless information enters one's frame of reference (observation/experience of reality, one's light cone) as you "move along your lifeline". It happens each and every single moment, a smooth, entirely lossless (native or lifelike) transition from one moment (event) to the next (breath by breath, Planck unit by unit, the position of a flying bee's wing from one fraction to the next). The only question that remains would be if said new information is pre-existing (as per an eternalist/tenseless, deterministic block universe model) and or if it comes into being in a nondeterministic fashion (as per presentism/tensed, growing/evolving block universe). More about this later.

     

    In my opinion, Wikipedia is hardly of more value for philosophical citations than this thread itself. Moreover, in this thread we are comparing disagreeing explanatory views of relativistic physics with each other - and not classical physics with relativistic physics.

     

    Thus, here above I filtered through the parts that seem to relate to explanatory power of the block universe on top of the mathematical explanatory power of the Poincare-Minkowski space-time formalism which is shared by the two models. I'll next read your links and try to see if I can distill more out of those that can be used to phrase the causal block universe explanations...

    Have you read the more technical Minkowski space​ article that I linked earlier?

     

    So far, no comparable logical explanation has emerged concerning the "double" time (two conceptually different "true times"?) of the Spacetime view; it remained more of a mystery than an explanation. If you would like to start a topic on that: yes please! :)

    It would seem that the thread got seriously side-tracked by the notion of double time. This was something that Michel brought up (I merely inserted his quote) and something that you (Tim) seemed to have agreed with him on. I referenced the source used by Wiki in that article as it links to a scientific paper on the subject. I did so specifically so that Michel and/or you may have a look at it and see if there was anything useful to be extracted from it.

     

    I will next deal with the last page and this confusion re so-called double time. In doing so, I think it will indeed be useful to use my previous illustration of the numeric sequence from -infinite to +infinite...

    Where is the logic in stating that "if the now moves then in must do so in respect to some reference?" Why is it that there has to be some reference?

     

    That presupposes the movement to be uniform.

     

    Why should it be?

     

    I actually prefer to reserve the word move or movement for change of spatial location and to choose another word for change of temporal location.

     

    Now the whole subject of rate of change requires at least two axes and there is only one temporal axis.

     

    This is basic analysis (calculus) in high school maths.

     

    So the whole argument is spurious.

     

    Koti, the "moving now" issue is the "double time" issue of block universe - I already discussed that in a thread on that topic [edit: see here]. That reference is thus utter nonsense.

     

    OK, back to my numerical sequence. Let me use the analogy of said number sequence (from -infinite to +infinite) being placed on a (very long, well basically infinite) ruler (or measuring tape). For the purpose of this discussion think of this ruler/measuring tape to be the time dimension, a flat foundation on which the 3-D events are "constructed". Now consider two scenario's:

     

    1. Point zero (theoretically in the middle of the ruler) corresponds to the present time, the now. All the positive numbers relate to the future, all negative numbers to the past. Consider yourself as the observer in the form of a tiny toy standing on top of the zero. So if you want to move the now, the zero (with the toy on top of it) has to move and as such the entire ruler has to move. Hence the question what is the now, the zero, the ruler moving in relation to? This refers to the moving now, the tensed or presentist theory.

     

    2. In the second scenario point zero corresponds with an event at that coordinate, let us say the big bang. All the numbers represent coordinates on different sides of the big bang (- to the one, + to the other). Imagine a physical 3-D hologram being constructed on top of the ruler, at each consecutive number it reflects a slightly different event/image/frame/slice. At point zero, said hologram will represent a singularity. Place the toy/observer on a coordinate (number) of let us say +13.8 billion to represent our current now. In order to move to the next now, just move the toy forward into its next holographic environment (with light, sound, oxygen to breathe, etc). So what has happened? Effectively each number on the ruler has now become a real event, a real now, one of many now's. This correlates with the standard block universe model (with eternalism & determinism).

     

    I hope that you can all spot the difference. We perceive ourselves in a flowing time, a moving now, whereas it may in fact be us (and our capacity to observe and to experience) moving along spacetime from one now (coordinate) to the other.

     

    Back to physics, to mechanics, to dynamics, etc. both classical and quantum. All of our scientific disciplines are reflections of how we perceive reality. Scientists have observed and measured certain natural phenomena, we have detected certain correlations and repetitions that enabled us to predict, to calculate, to design, or to accept the uncertainty thereof (for example in QM). That, however, does not rule out the hypothetical fixed ruler (time dimension) with its lossless 3-D space hologram as part of a "prefabricated" 4-D block universe, or for that matter any ongoing/flowing experience (incl biological functions, dynamics, mechanics, etc) of each moment within it.

     

    * FINAL EDIT *

  14. I don't know how you want to use reduced time consciousness for this discussion; but since that person's movements of arms and legs probably uses a kind of PID control (and that implies again activation of speed cells and "time" dynamics), I don't think that that would be a totally different "ball game".

    We are still the same living, moving biological entities brought about by the same tools of what we understand to be evolution. The block universe model does not alter any of that. We are moving through- and experiencing our lifelines that are embedded in it, breathing actual oxygen on the way. You know perfectly well why I brought that analogy into the discussion. It is important to envisage, or imagine a different reality (from that on Earth) such as the one that I tried to illustrate. It brings a total new perspective to the way we look at these issues.

     

    Memammal, that very well might be the case, at least with me :) Can you recommend a book that would be a comprehensive source on this ?

    The link that I provided earlier is about the easiest to digest: Time, Free Will and the Block Universe

    * EDIT: The article itself is part of a series, as far as I remember, so there are other references and pages linked to it.

     

    As for my possibly unjustified concern, let me rephrase;

    Eternalism states that all points in time are equally real (wiki) If I understand this correctly, at the big bang there had to be a stage in which a continumm of all future events had to be presented...and had to be presented instantly. This sounds extremely far fetched if not ridiculous.

    Eternalism posits that there was no beginning (or end) from within the block universe. Seeing that our conventional understanding of time is no longer valid (as per Einstein & Co) and since we cannot tell whether the universe is finite of infinite in size, it is akin to you asking how it was possible that ALL numeric numbers (from -infinite to +infinite) were introduced at the same "moment", let us say at point zero? In fact this seems like a nice illustration...are all numbers equally real, do they all exist, do they change?

    And I really wonder if we did a poll, what percentage of people would vote for "block".

    And I really hope this does not turn into a popularity contest, Tim ;)

  15. It was Einstein who revolutionised the way scientists perceive time, no? Four-dimensional Euclidean spacetime, Minkowski space and the block universe model(s) resulted from it.

    Ehm no, not really, and different scientists perceive time differently; even this thread is witness thereof. A lot of things are pushed into Einstein's shoes (as no doubt also with Newton), but that one was mostly not Einstein's doing. His philosophy was formed and influenced by the people he frequented such as Lorentz and Minkowski. But I read that according to his autobiography he was first of all influenced by Hume and Mach.

     

    Not that it matters much for us; we must make up for ourselves what metaphysics we deem most plausible.

    Quoted from Absolute space and time​:

    • In Einstein's theories, the ideas of absolute time and space were superseded by the notion of spacetime in special relativity, and curved spacetime in general relativity.​
    • The theory of relativity does not have a concept of absolute time because there is a relativity of simultaneity. An event that is simultaneous with another event in one frame of reference may be in the past or future of that event in a different frame of reference, which negates absolute simultaneity.
    • Even within the context of Newtonian mechanics, the modern view is that absolute space is unnecessary.
    • Special relativity eliminates absolute time (although Gödel and others suspect absolute time may be valid for some forms of general relativity)[16]...
    • [This may be an important source as it could link back to quote from Michel: Something like a "double time" is needed in this concept too.]
    • ...and general relativity further reduces the physical scope of absolute space and time through the concept of geodesics. There appears to be absolute space in relation to the distant stars because the local geodesics eventually channel information from these stars, but it is not necessary to invoke absolute space with respect to any system's physics.​​​

    The above then also in reaction to:

    If nobody comes here to clarify how otherwise a block universe model of reality is useful for explaining relativistic physics, then it will start to look rather poor and weak compared to Absolute Space...

     

    And from Relativistic dynamics:

    • Einstein rejected the Newtonian concept and identified t as the fourth coordinate of a space-time four-vector. Einstein's view of time requires a physical equivalence between coordinate time and coordinate space.
    • The role of time was a key difference between Einsteinian and Newtonian views of classical theory.

    As for this:

    And I repeat my nonsense: what element proves us that the past is "frozen"? That it still exist somehow in the past cone?

    I don't quite follow the logic behind this comment. How do you propose for the past to be changed, to be unfrozen? Surely you can understand that if you were able to observe a spacetime coordinate that sits somewhere in the "past", you will observe the exact same event..? What else?

     

    BTW...Wouldn't there be an issue (at least a philosophical one) with the block universe concepts concerning the amount of information involved?

    Considering the original block concept where the past, present and future are done events wouldn't that mean that at or right after the big bang spacetime would have to be "stuffed" with a ridiculuos amount of information?

    Interesting idea! Even if we assume that the "Space" part of Spacetime is finite, how about the eternal "time" part that is supposedly present and existing? That does sound huge, and "infinite" sounds as quite too much...

    With all due respect, it seems to me that you guys really do not grasp the model at all. The idea of the standard block universe model is that it is done and dusted, a complete package. It is also not dependent on us observing all of it (we observe what we have access to during our lifeline). It would not have existed in its current form if there was not enough "space". You might as well imply that there is not enough space for the universe..? So I don't quite follow your logic here (as with Michel). Let us consider the alternative. In stead of everything already existing, we have "new information" coming into existence ex nihilo every nanosecond; is that a more viable option? BTW, keep in mind that the BB was just one of many events/points within the bock universe.

     

    OK, unfortunately I have to run again. I hope this would make some sense. FINAL EDIT

  16. OK. Apparently such person will still have a sense of time; however it will be less developed, as there isn't much more than that person's internal "clock" to go on. Interestingly, yesterday I heard in a talk that even red blood cells have a biological clock, so that their conductivity changes with the hour of the day.

    However, it's not clear how that is useful for explaining laws of physics...

    Probably so as it may be a result of evolutionary adaptation to our particular eco-system and as such not something that is likely to change within one generation. I was however attempting to provide an analogy of a person having to operate in deep space without any references/memories of conditions on Earth. That would be a totally different ball game, not so?

     

    Of course, better would have been if you had made a synthesis yourself, but I understand that you also are busy.

    The articles that I referenced are mostly short and concise, except the one re Minkowski space...that one is pretty detailed (for reasons that would be apparent). There are a few important aspects contained within those articles, some that you and michel have raised in recent posts, so well worth the read especially by casual readers of this thread. I will try to highlight and elaborate on some of them a bit later.

     

    I'll look at it and see what of that material can be used for showing how "block universe" metaphysics can be helpful for making sense of physics - if only to be fair.

    Lol. Yes, kindly be fair to what has become one of- if not the best explanation for our current understanding of physics...even though physicists generally have a love/hate relationship with it because of that darn fixed future feature.

  17. Have you heard of something called Quantum Biology? Here are a few links to some interesting reading material:

    A scientific review of the subject

    Wiki article

    BBC article

     

    I saw an insert on Through The Wormhole (TV series) that dealt with something similar to this. The episode was called "Is There a Sixth Sense?" and dealt with that, telepathy, global consciousness and if I remember correctly it also touched on animal group behaviour (bee's, birds, fish, etc).

  18. Tim88, this is indeed a very informative thread. I think we just need to be careful to not confuse ourselves and others and in the process get lost among Newtonian dynamics, Newtonian time, Einsteinian time, "cosmological time", Planck time and/or Planck constants, our human construct of Earth bound reality vs that of outer space, etc. Unfortunately I have been side-lined (and still am) with other pressing matters, otherwise I would have attempted to contribute more constructively to this discussion. That being said, it appears that you have questioned certain specific comments made by ajb & Mordred and it will probably be better if they themselves respond to those points.

     

    Let me just quickly throw this in. We have a human construct of reality that is unavoidably link to our specific, albeit dynamic eco system. We sense time in the passing of day to night, from tide to tide, from season to season while we are bound by our dense atmosphere that provides us with an intimate sense of classical mechanics. Now let us (quickly) consider the concept of time. Imagine the way Mayflies (24 hour living span) versus a giant barrel sponge Xestospongia muta​ (approx. 2,400 years living span) would perceive time here on Earth. Think about it. Let us further imagine a human who is born on an intergalactic space craft on route to a galaxy far, far away. Imagine said person's sense of time and dynamics in a totally dark, totally weightless environment (consider for example said astronaut pushing him/herself in a direction and his/her illusion of movement...what is moving in relation to the other?).

     

    It was Einstein who revolutionised the way scientists perceive time, no? Four-dimensional Euclidean spacetime, Minkowski space and the block universe model(s) resulted from it. In order for readers of this thread to get to grips with some of the fundamental basics of the various approaches that have been raised, I suggest the following background reading:

     

    Absolute space and time​ (this article contrasts the classical views nicely with that of Einstein)

    Minkowski space​

    Relativistic dynamics

     

    ​And until I have more time to try and explain the various kinds of block universe models and the somewhat misleading interpretation of "frozen events" (as if it prohibits movement...opposed to change), let me leave you with a link to an article about a recent attempt by some of the world's most renowned physicists to reconstruct the block universe model (which seems to be very fitting to the thread):

     

    A Debate Over the Physics of Time

    According to our best theories of physics, the universe is a fixed block where time only appears to pass. Yet a number of physicists hope to replace this “block universe” with a physical theory of time.

     

    Let me also add these:

    Time, Free Will and the Block Universe (copied from other threads)

    Growing Block Universe

     

    * Edited to correct a grammar error *

  19. That seems to be a very naive approach. Enclosing one of the leading democratic capitalist societies that was formed by immigrants for immigrants beyond its own wall, is not very American. Keeping its military might out of other people's business may indeed be a step in the right direction, but there is that subtle (and way too subtle for Trump to comprehend) yet vital responsibility to keep the various world powers in check. As was mentioned elsewhere/earlier, the USA government can afford to sustain a large military presence in other parts of the world because those foreign powers want them there and thus finance the costs of having them there. It is cheaper to have military bases in some other parts of the world than having them in the U.S.A., for example. Trump seems entirely oblivious to this reality.

  20. I find it rather interesting that a lot of medical practitioners tend to "compartmentalize" their medical knowledge and expertise separately from their (strong) religious beliefs. I have seen this quite often. A personality trait common among M.D.'s...in the gene's, so to say..?

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