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Does time exist?

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  • Registered Users Posts: 26 Upthedubs32


    roosh wrote: »
    I too use a clock as a tool for organising my life, I recall memories of times past, I project images of times in the future, but never have I actually ever spent any time outside the present moment.

    The clock is very useful indeed; originally it was used to measure the apparent motion of the sun around the earth, and to break that motion into more manageable chunks, so that people could arrange things more easily, so that they think more easily about how much daylight they had to carry out the things they needed to do; it allowed them to communicate with others about things that needed to be done. The clock has evolved however, and now we have pendulum clocks, digital clocks, and atomic clocks.

    But if I consider any of these clocks, if I open them up and look at their internal mechanisms (or even just think about doing it), I start to wonder, where is this thing that "happens as a part of nature" actually measured? I can see all the parts of the clock that are "a part of nature"; if I think of a sundial, I can see that the sun is a part of nature and so too is the matter that makes up the sundial, but where, oh where, is this mysterious other aspect of nature called time?

    Now thats a reply that i dont mind spending TIME reading! I think the fact that you are so intrigued by it all says alot about you and ive always been the same but with a differience, i wonder more about the mechanical end of things and how they work rather than how they exsist, the evolution of time keeping from sundials to atomic clocks would tick all my boxes.

    I hope that you get closer to what it is your looking for!! And that you get plenty of enjoyment from the searching

    Gavin


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote: »
    Also, just for posterity, it is probably worth highlighting that the notion of an absolute present is perfectly compatible with Lorentzian relativity, which is equally supported by all relativity experiments.

    Lorentzian relativity, rejected by the majority of the scientific community for its inelegant baggage of superfluous ad-hoc assumptions.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    Now thats a reply that i dont mind spending TIME reading! I think the fact that you are so intrigued by it all says alot about you and ive always been the same but with a differience, i wonder more about the mechanical end of things and how they work rather than how they exsist, the evolution of time keeping from sundials to atomic clocks would tick all my boxes.

    I hope that you get closer to what it is your looking for!! And that you get plenty of enjoyment from the searching

    Gavin

    Cheers Gav.

    The "searching" can be both sweet and sour, but it can often provide some insights into "the self".

    Incidentally, I would say that the question of how a clock measures time is, ultimately, a mechanical one. It is a question of how the mechanics of a clock measure the (physical) temporal dimension. I personally can't see how they do; unless it is assumed they do.


  • Registered Users Posts: 147 ✭✭citrus burst


    I need time for change,

    I don't need change for time


  • Registered Users Posts: 2,552 ✭✭✭roosh


    I need time for change,

    I don't need change for time

    change doesn't need time, "time" comes from change.


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  • Registered Users Posts: 32,802 ✭✭✭✭NIMAN


    Time doesn't exist?

    So I wasted all that money on what I thought was a perfectly good wrist watch.

    Can I take it back to the shop and ask for a refund under the Trade Descriptions Act?


  • Registered Users Posts: 2,512 ✭✭✭Ellis Dee


    The only thing "psychological" about time is our human perception of it. Time itself is a reflection of the expansion of the universe, which began with the "Big Bang".


    Of course, I might be wrong and time is actually only a gimmick invented by the Swiss to help sell watches.
    <snip> reproduced comics


  • Registered Users Posts: 2,552 ✭✭✭roosh


    NIMAN wrote: »
    Time doesn't exist?

    So I wasted all that money on what I thought was a perfectly good wrist watch.

    Can I take it back to the shop and ask for a refund under the Trade Descriptions Act?
    You probably could; but it'll be your word against theirs that they they made an ontological claim about the existence of time when selling it to you.

    Those crafty watch salespeople!


  • Registered Users Posts: 153 ✭✭Zaffy


    Well if you think about it,

    Do things happen because time passes

    Or does time pass because things happen?

    Imagine, say nothing in the world was changing. Everything was still. No movement, no forces, no anything. Consider one moment. Now consider a minute on from that. Then an hour. A day. A month. A year. It's still the same. Nothing has changed. How do we know how long has passed if we have nothing to gauge it by?

    But now the inverse. Say we imagine time isn't passing, but things change. If something started of at point A, then moved to point B, while time isn't changing, did it start at A? or at B? or at some point inbetween A and B. If everything happens simultaneously, then how do you know where it started/finished?

    My thoughts on the subject.


  • Registered Users Posts: 1,821 ✭✭✭18AD


    Zaffy wrote: »
    Imagine, say nothing in the world was changing. Everything was still. No movement, no forces, no anything. Consider one moment. Now consider a minute on from that. Then an hour. A day. A month. A year. It's still the same. Nothing has changed. How do we know how long has passed if we have nothing to gauge it by?

    If you're saying that change is time then you can't have a changless universe that doesn't change for an hour or a day. Cause if the change is time, then the static universe isn't static for any amount of time. The idea of it being the same doesn't make sense either, because there's no other event (at a different time) to compare it to.
    But now the inverse. Say we imagine time isn't passing, but things change. If something started of at point A, then moved to point B, while time isn't changing, did it start at A? or at B? or at some point inbetween A and B. If everything happens simultaneously, then how do you know where it started/finished?

    I guess here again if time is change then the movement itself cannot be thought of as moving from A to B because there's no time.

    I think there's a version of time which takes time to be three dimensional. So the movement from A to B has already all happened already. Our limited perspective only allows us to see one slice of the three-dimensional time-worm. So maybe your example is thinking this kind of time minus the limited perspective we have of individual moments.


    I hope that's somewhat clear. :pac:

    I probably said this before, but this is a cool topic. I don't think it's very widely discussed either. Which is always good!


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  • Registered Users Posts: 2,552 ✭✭✭roosh


    Zaffy wrote: »
    Well if you think about it,

    Do things happen because time passes

    Or does time pass because things happen?

    Imagine, say nothing in the world was changing. Everything was still. No movement, no forces, no anything. Consider one moment. Now consider a minute on from that. Then an hour. A day. A month. A year. It's still the same. Nothing has changed. How do we know how long has passed if we have nothing to gauge it by?

    But now the inverse. Say we imagine time isn't passing, but things change. If something started of at point A, then moved to point B, while time isn't changing, did it start at A? or at B? or at some point inbetween A and B. If everything happens simultaneously, then how do you know where it started/finished?

    My thoughts on the subject.

    We can still order events as A happens before B, this is what we do regardless, and has more to do with the human capacity for memory than it does with the physical existence of time.

    We have a present moment which is continuously changing; we remember how the present used to be and label that as A; we label our current experience of the present as B, and say that A happened before B. There is no need for a physical property, called time, to change in any of this. It is the changing present, and our memory of a previous present state, which creates the illusion of time.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    18AD wrote: »
    I think there's a version of time which takes time to be three dimensional. So the movement from A to B has already all happened already. Our limited perspective only allows us to see one slice of the three-dimensional time-worm. So maybe your example is thinking this kind of time minus the limited perspective we have of individual moments.

    Are you referring to "the block universe" interpretation there, where spacetime is 4D, and we only experience our "now slice" of the block universe.

    That interpretation requires, I think, a number of unjustified assumptions. For example, as you mention, all events have already occurred. This means that "your future" already exists, and that "your past" continues to exist, in some temporal, but acutal sense i.e. your 8th birthday is in progress - without getting into semantical debates about it happening "now".

    There is, however, no empirical evidence to suggest that your future already exists, or that your past continues to exist; no such evidence exists for any observer - not least because they can only ever experience their "now slice". This requires the assumption, on behalf of every observer, that their past, present, and future, somehow, co-exist.


    A number of questions arise from that; if we take the example of your 8yr old self having his/her birthday party, the natural question would be, how did your 8yr old self not age as you aged? You were that 8yr old, and you grew to be whatever age you are now; how did the 8yr old you not age along with you; how can he/she still be having their 8th birthday party?

    The answer to that conundrum, I think, appears to be that we, somehow, exist as geometrical "world lines" already plotted out in absolute spacetime. This further gives rise to the question, if we are geometrical world lines, with an absolute existence in spacetime, and not necessarily moving - but moving through time?? - then how is there the illusion of relative motion between observers and objects? How do these non-moving worldlines experience relative motion?


  • Registered Users Posts: 1,821 ✭✭✭18AD


    roosh wrote: »
    Are you referring to "the block universe" interpretation there, where spacetime is 4D, and we only experience our "now slice" of the block universe.

    Yup.
    A number of questions arise from that; if we take the example of your 8yr old self having his/her birthday party, the natural question would be, how did your 8yr old self not age as you aged? You were that 8yr old, and you grew to be whatever age you are now; how did the 8yr old you not age along with you; how can he/she still be having their 8th birthday party?

    I think you're mistakenly taking the younger and older self to be different, especially when you say the 8yr old should age along with you. Both would be connected as a unity through time. The 8yr old at the 3rd of April is the same as the 8yr old on the 9th of April. The 8yr old on the 3rd of April is always that age, ie. no one ever ages in any real sense of the word, they simply experience the individual moments along the static timeline of their existence.

    They are still having their birthday party, but by they it's just you. Your past self is statically frozen as an extended temporal birthday party. In fact the you that is going to reply to this has already done so, it's just that your awareness of that moment has not caught up to it yet. In effect you are always moving into your future self.

    I think however, that this doesn't really solve or elucidate the nature of time at all. All that has happened is that there is now something else we have to explain, namely, how the 'now' point moves along the frozen 4-Dimensional time space. Everything exists already, but they don't all exist as 'nows', so why not?

    I think you're right on the empirical comment, however I think the notion of 4-Dimnesional time has arisen rather as an attempt to overcome some of the conceptual problems of regular time. (Don't ask me what those are :p)
    The answer to that conundrum, I think, appears to be that we, somehow, exist as geometrical "world lines" already plotted out in absolute spacetime. This further gives rise to the question, if we are geometrical world lines, with an absolute existence in spacetime, and not necessarily moving - but moving through time?? - then how is there the illusion of relative motion between observers and objects? How do these non-moving worldlines experience relative motion?

    I'm not too familiar with relative motion to be honest. Will I even hazard a guess... :o Maybe if we could furnish a simple example of it for myself. Oh yeah, so the basic example of the twin who travels around the earth a near light speed and returns to his more aged twin.

    Would it be possible to explain this in the sense that the progression through time, the consecutive 'nows' for each observer are not progressing at the same speed? You don't need different time lines because the 4-D timeworm is essentially 3-D extended through time, it's not just a line, which is 1-D. The person at near light speed is travelling through the static time faster than the other people. I think you just need to say that there are different 'now' points in 4-D time.

    :confused::confused::confused: Sorry for my poor explaining!


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote:
    The answer to that conundrum, I think, appears to be that we, somehow, exist as geometrical "world lines" already plotted out in absolute spacetime. This further gives rise to the question, if we are geometrical world lines, with an absolute existence in spacetime, and not necessarily moving - but moving through time?? - then how is there the illusion of relative motion between observers and objects? How do these non-moving worldlines experience relative motion?
    18AD wrote: »
    I'm not too familiar with relative motion to be honest. Will I even hazard a guess... :o Maybe if we could furnish a simple example of it for myself. Oh yeah, so the basic example of the twin who travels around the earth a near light speed and returns to his more aged twin.

    Would it be possible to explain this in the sense that the progression through time, the consecutive 'nows' for each observer are not progressing at the same speed? You don't need different time lines because the 4-D timeworm is essentially 3-D extended through time, it's not just a line, which is 1-D. The person at near light speed is travelling through the static time faster than the other people. I think you just need to say that there are different 'now' points in 4-D time.

    :confused::confused::confused: Sorry for my poor explaining!

    A few things to say about this:

    The length of a world line interval is a measure of the time experienced across that interval.

    For a point particle, the world line is 1D. For a 1D string, it would be a 2D "world sheet" etc. This is one of the reasons why string theory is desirable. World sheets are much easier to deal with in quantum mechanics.

    Relative motion manifests as a difference in the shape of two world lines. If we consider the simple case of a globally flat spacetime (I.e. No gravitational pull), two objects at rest with respect to each other will have parallel world lines.


  • Registered Users Posts: 1,821 ✭✭✭18AD


    I think the world line is slightly different from philosophical 4-Dimensionalism.

    For 4-Dimensionalism objects aren't travelling through 4D spacetime, they are fixed at all points. Their past and future states already and always exist.

    I think the world lines are a measure of movement through spacetime and is not saying that the past states still exist. Would I be right in saying that?

    For 4Dism sapcetime is the temporal and material extension of objects, it's not something through which they pass.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    18AD wrote: »
    I think the world line is slightly different from philosophical 4-Dimensionalism.

    For 4-Dimensionalism objects aren't travelling through 4D spacetime, they are fixed at all points. Their past and future states already and always exist.

    I think the world lines are a measure of movement through spacetime and is not saying that the past states still exist. Would I be right in saying that?

    For 4Dism sapcetime is the temporal and material extension of objects, it's not something through which they pass.
    Does the world line not represent the object in spacetime; that is, the object is fixed at all points and would be represented by a line?

    It appears to be a pretty big assumption, though, that past and future states already and always exist; I think it stands in the realm of the unverifiable.

    Also, how can static objects, represented by worldlines perhaps, give rise to the perception of relative motion?


  • Registered Users Posts: 1,821 ✭✭✭18AD


    roosh wrote: »
    Does the world line not represent the object in spacetime; that is, the object is fixed at all points and would be represented by a line?

    I'm not sure what the status of the world line is. If it's just representing the movement of the object through time it's not necessarily saying it still exists at those points, whereas 4Dism is saying that. Morbert is probably in a better position to clarify the world line idea.
    It appears to be a pretty big assumption, though, that past and future states already and always exist; I think it stands in the realm of the unverifiable.

    Probably. But as philosophy it's often just looking for the necessary conditions of time, e.g. things must always already exist in past, present and future.

    Not that I agree. It just is what it is.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    18AD wrote: »
    I'm not sure what the status of the world line is. If it's just representing the movement of the object through time it's not necessarily saying it still exists at those points, whereas 4Dism is saying that. Morbert is probably in a better position to clarify the world line idea.
    I presume that the worldline could be used to plot the movement of an object, without necessarily assuming that it's past and future states always exist; but based on the discussion in this thread, I think the worldline does represent an object in spacetime, also, or the object in 4-Dimensionalism could be represented as a worldline.

    18AD wrote: »
    Probably. But as philosophy it's often just looking for the necessary conditions of time, e.g. things must always already exist in past, present and future.

    Not that I agree. It just is what it is.
    Why would you say they are the necessary conditions of time?

    I would say that things used to exist, but existed in the present, which subsequently changed. They don't exist in the future, nor will they ever; they only ever exist in the present.


  • Registered Users Posts: 1,821 ✭✭✭18AD


    roosh wrote: »
    Why would you say they are the necessary conditions of time?

    I think one of the problems that 4Dism tried to solve was reference to past events. So I talk about yesterdays dinner, I must be refering to something for the words to mean anything. Otherwise I'm refering to nothing and it loses meaning. So the 4Ders go as far as to state that the objects (necessarily) always exist, otherwise our talking about them wouldn't make any sense.

    I haven't kept up with the debate on this issue, so it may actually be rather dated!
    I would say that things used to exist, but existed in the present, which subsequently changed. They don't exist in the future, nor will they ever; they only ever exist in the present.

    That would make you a Presentist :p

    Edit: It certainly looks like 4Dism and world lines may be the same thing according to that wiki page. "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."


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote:
    Also, how can static objects, represented by worldlines perhaps, give rise to the perception of relative motion?
    Morbert wrote:
    Relative motion manifests as a difference in the shape of two world lines. If we consider the simple case of a globally flat spacetime (I.e. No gravitational pull), two objects at rest with respect to each other will have parallel world lines.

    18AD: A world "line" of an object is the locus of all events that make up that object. 4D spacetime is adopted because of the equivalence it exhibits between space and time, which has lead to a comprehensive, experimentally established theory of the quantum world.


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  • Registered Users Posts: 2,552 ✭✭✭roosh


    Morbert wrote: »
    18AD: A world "line" of an object is the locus of all events that make up that object. 4D spacetime is adopted because of the equivalence it exhibits between space and time, which has lead to a comprehensive, experimentally established theory of the quantum world.
    Have Quantum Mechanics and Einsteinian relativity been fully reconciled, and does such a reconciliation lead to something termed "the problem of time", where both theories appear to use different conceptualistions of time?


  • Closed Accounts Posts: 251 ✭✭UNIFLU


    roosh wrote: »
    Personally I believe that time does not exist, that it is merely a figment of the imagination of mankind, and our subsequent belief that it is an external force acting in the universe, makes it, by definition, an illusion.

    Its a beautiful way to look at our experience of being when you attempt to remove time concepts from the experience. I find that the thought of a rolling now (excuse my lack of scientific know how!) as a relay of snaps in our experience is a beautiful mental expression of my experience, the cataloging of which may well be defined through the concept of time as there needs somehow to be a relative and recurring constant by which to relate it to and quantify it.

    Also just a side thought - If we had two earths both of which had a moon and sun, gave them both inhabitants and our methodology to calculate time but with the planets at vastly different distances from each other they are both going to create concept of time units but their concept of a second are going to be mathematically different? (correct i think???). How would they reconcile time as a measurement?

    Just my grubby penny thought.


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote: »
    Have Quantum Mechanics and Einsteinian relativity been fully reconciled, and does such a reconciliation lead to something termed "the problem of time", where both theories appear to use different conceptualistions of time?

    Quantum mechanics and special relativity have been fully reconciled. The postulate that space and time are on equal footing, and part of a larger relation called spaceime has produced some of the most accurate predictions in physics.

    Quantum mechanics and General relativity have not been fully reconciled because of the dynamics of the gravitational field. One approach has been to canonically quantize the Hamiltonian in the context of a uniquely foliated space-time. I.e. Slice spacetime into 3D spaces, parametrised by a parameter, and build quantum mechanics in this context. This does not result in presentism, however. The gauge parameter, used to construct quantum mechanics and the presentist "time label", are not equivalent. All you can say about these particular slices is they make the maths easier.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    Morbert wrote: »
    Quantum mechanics and special relativity have been fully reconciled. The postulate that space and time are on equal footing, and part of a larger relation called spaceime has produced some of the most accurate predictions in physics.

    Quantum mechanics and General relativity have not been fully reconciled because of the dynamics of the gravitational field. One approach has been to canonically quantize the Hamiltonian in the context of a uniquely foliated space-time. I.e. Slice spacetime into 3D spaces, parametrised by a parameter, and build quantum mechanics in this context. This does not result in presentism, however. The gauge parameter, used to construct quantum mechanics and the presentist "time label", are not equivalent. All you can say about these particular slices is they make the maths easier.
    and how do static worldlines give rise to the perception of relative motion?


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote: »
    and how do static worldlines give rise to the perception of relative motion?

    Relative motion manifests as a difference in the shape of two world lines. If we consider the simple case of a globally flat spacetime (I.e. No gravitational pull), two objects at rest with respect to each other will have parallel world lines.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    Morbert wrote: »
    Relative motion manifests as a difference in the shape of two world lines. If we consider the simple case of a globally flat spacetime (I.e. No gravitational pull), two objects at rest with respect to each other will have parallel world lines.

    This explains how we would graph the two worldlines of two different objects; that is, it explains what shape two worldlines would have; it doesn't explain how two static worldlines, at angles to each other, give rise to the perception of relative motion.

    Also, what about "the Problem of time" in Quantum Gravity and Cosmology that prompted Lee Smolin to teach this series of lectures - regardless of his own personal opinion on the matter.

    Also, what about the Wheeler-Dewitt equation which appears to suggest a timeless universe?


    EDIT: I think you're putting the cart before the horse in the above formalism; I don't think it is accurate to say that relative motion manifests as a difference in the shapes of two worldlines, because the shape of the worldlines isn't what manifests in the physical world, it's the relative motion that manifests. So it would be more correct, I think, to say that the difference in shape of two worldlines manifests as relative motion - the question remains as to how this happens.


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote: »
    This explains how we would graph the two worldlines of two different objects; that is, it explains what shape two worldlines would have; it doesn't explain how two static worldlines, at angles to each other, give rise to the perception of relative motion.

    EDIT: I think you're putting the cart before the horse in the above formalism; I don't think it is accurate to say that relative motion manifests as a difference in the shapes of two worldlines, because the shape of the worldlines isn't what manifests in the physical world, it's the relative motion that manifests. So it would be more correct, I think, to say that the difference in shape of two worldlines manifests as relative motion - the question remains as to how this happens.

    Your conflating terms again. By manifest, I mean that is how the observation of relative motion manifests in the spacetime structure of events.
    Also, what about "the Problem of time" in Quantum Gravity and Cosmology that prompted Lee Smolin to teach this series of lectures - regardless of his own personal opinion on the matter.

    Also, what about the Wheeler-Dewitt equation which appears to suggest a timeless universe?

    And as I explained before, the timeless universe they are talking about is not the presentist universe you are talking about.


    Go to 18:19

    "Not only is all of the past and all of the future present, but all possibilities of the past and future."

    The difference is, in vanilla relativity we have events within a 4D spacetime. In the "non-time" model, we have a space of all possible configurations of the universe.


  • Registered Users Posts: 2,552 ✭✭✭roosh


    Morbert wrote: »
    Your conflating terms again. By manifest, I mean that is how the observation of relative motion manifests in the spacetime structure of events.
    It isn't me that is conflating terms, but you may just have misunderstood the question. The question was, how does the spacetime structure of events manifest as relative motion i.e. how do static worldlines, ultimately at rest relative to each other manifest as relative motion?

    Morbert wrote: »
    And as I explained before, the timeless universe they are talking about is not the presentist universe you are talking about.

    " frameborder="0" allowfullscreen>
    I wasn't referring to Barbour's theory, although I wonder does his theory incorporate the idea of a universally shared present moment?

    I was specifically referring to "the problem of time", as per the lecutre seires given by Lee Smolin, and also the Wheeler-DeWitt equation:
    The Wheeler-DeWitt equation embodies a stark form of presentism: it simply tells us which states the universe can find itself in, and says nothing about any evolution through time.
    What if time really exists?


  • Registered Users Posts: 3,457 ✭✭✭Morbert


    roosh wrote: »
    It isn't me that is conflating terms, but you may just have misunderstood the question. The question was, how does the spacetime structure of events manifest as relative motion i.e. how do static worldlines, ultimately at rest relative to each other manifest as relative motion?

    And I said it is the shape of the world lines that exhibit the relative motion we associate with observers and objects. If you're asking why we don't atemporally perceive the entire world line of ourselves, that boils down to the question of how perception manifests from things, an open question.
    I wasn't referring to Barbour's theory, although I wonder does his theory incorporate the idea of a universally shared present moment?

    I was specifically referring to "the problem of time", as per the lecutre seires given by Lee Smolin, and also the Wheeler-DeWitt equation:
    What if time really exists?

    They are the same theory: "The Wheeler-DeWitt equation embodies a stark form of presentism: it simply tells us which states the universe can find itself in, and says nothing about any evolution through time. " Is equivalent to Julian Barbour's:"The quantum universe is likely to be static. Motion and the apparent passage of time may be nothing but very well founded illusions." I.e. They are saying the universe is an unchanging configuration space, and change is an illusion generated by the Hamiltonian. The "present" in this case, is not a single 3D hypersurface, but rather all possible hypersurfaces, and all possible configurations.


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  • Registered Users Posts: 2,552 ✭✭✭roosh


    Morbert wrote: »
    And I said it is the shape of the world lines that exhibit the relative motion we associate with observers and objects. If you're asking why we don't atemporally perceive the entire world line of ourselves, that boils down to the question of how perception manifests from things, an open question.
    And again, I was asking how static worldlines can exhibit the relative motion we associate with observers and objects.

    If it is indeed an open question, it is limited in its scope, and would require a fairly mystical explanation.


    Morbert wrote: »
    They are the same theory: "The Wheeler-DeWitt equation embodies a stark form of presentism: it simply tells us which states the universe can find itself in, and says nothing about any evolution through time. " Is equivalent to Julian Barbour's:"The quantum universe is likely to be static. Motion and the apparent passage of time may be nothing but very well founded illusions." I.e. They are saying the universe is an unchanging configuration space, and change is an illusion generated by the Hamiltonian. The "present" in this case, is not a single 3D hypersurface, but rather all possible hypersurfaces, and all possible configurations.
    Presentism is the idea that only the present moment exists; so regardless of the configuration of hypersurfaces, the Wheeler-DeWitt equation embodies a stark form of the idea that only the present moment exists.

    I'm not entirely sure about the idea of a 3D hypersurface, but, if I understand correctly, I don't have too much trouble with the idea that the universe is an unchanging configuration space and that change is an illusion.

    Still, it would represent presentism though.

    EDIT: it is probably worth clarifying the point about change being an illusion; change still manifests in the physical world we experience, but the physical world we experience is illusory.


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