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Absolute motion
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Oh God. I am sorry.0
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Masteriod, you have the right idea but I wouldn't employ the convoluted analogies. What you are describing is effectively a function.
Roosh, I didn't miss your post. I just post in the philosophy forum less often as I find the conversations less compelling. But yes, there would be no physical transition between you at 9:05, and you at 23:31, wondering why you still aren't frozen at 9:05. Both events would make up a part of your worldline.0 -
Masteriod, you have the right idea but I wouldn't employ the convoluted analogies. What you are describing is effectively a function.
Fair comment. I just thought the discussion was bogged down for reasons that don't really apertain to the question of how motion can be manifest to our consciousness on the basis that we don't perceive motion but instead perceive events that are as a result of a body we deduce to be in motion.
But I wonder, what are your views on what would constitute an event? How could an object undergo a change in momentum without 'motion' of some sort occuring?
Oh, and would you describe the 'Twin Paradox' as a convoluted analogy?0 -
Fair comment. I just thought the discussion was bogged down for reasons that don't really apertain to the question of how motion can be manifest to our consciousness on the basis that we don't perceive motion but instead perceive events that are as a result of a body we deduce to be in motion.
But I wonder, what are your views on what would constitute an event? How could an object undergo a change in momentum without 'motion' of some sort occuring?
Oh, and would you describe the 'Twin Paradox' as a convoluted analogy?
An event is a "location" in spacetime. The events themselves do not undergo a change in momentum. Instead, we consider a set of events that represent the history of an object, and we note that, at different points along the history of the object, the momentum of the object can be different.
I wouldn't call the Twin scenario an analogy. It's a thought experiment.0 -
An event is a "location" in spacetime. The events themselves do not undergo a change in momentum. Instead, we consider a set of events that represent the history of an object, and we note that, at different points along the history of the object, the momentum of the object can be different.
I wouldn't call the Twin scenario an analogy. It's a thought experiment.
Is that to say that we don't note a change in the spacetime coordinates of an object that appears to be in motion?
You seem to be saying that an object is a collection of events and that an event is a location in spacetime. This means an object is a collection of locations in spacetime, the entire collection costituting the object's entire history.
Is this what you meant, that spacetime itself exhibits a property that gives rise to events and that those events are manifest as objects?
This as opposed to an object being a set of events that are distinct and incidental to the space they occupy.0 -
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That's fair enough; but my experience of the "narrative" of my worldline should not have extended beyond that day and that time, but yet here I am. While you might argue that this is a different me "here and now", you still have to explain how I got from that me, to this me.Roosh, I didn't miss your post. I just post in the philosophy forum less often as I find the conversations less compelling. But yes, there would be no physical transition between you at 9:05, and you at 23:31, wondering why you still aren't frozen at 9:05. Both events would make up a part of your worldline.0 -
That's fair enough; but my experience of the "narrative" of my worldline should not have extended beyond that day and that time, but yet here I am. While you might argue that this is a different me "here and now", you still have to explain how I got from that me, to this me.
Nobody is saying you got from that you to this you. You're not treating time consistently. I am instead saying the "yet here I am" you has memories of the "9:05" you, and all "yous" in between.0 -
That's fair enough; but my experience of the "narrative" of my worldline should not have extended beyond that day and that time, but yet here I am. While you might argue that this is a different me "here and now", you still have to explain how I got from that me, to this me.
Think of the whirlpool located at a place on a river again roosh.
There are two parts to a whirlpool, the energy of the river that causes the whirlpool to form, which is a 'static' force in that the whirlpool vortex is shaped by the interaction of the energy of the river and the physical landscape, and the water molecules themselves as they pass through the system.
You can see how although we might be observing one persisent whirlpool, we also observe that the water of which the whirlpool is comprised is being constantly renewed. Water molecules enter the system and then they must eventually leave.
Well, 'self' is like the persistent feature of a whirlpool and 'events' are like the water molecules entering and leaving the space affected by the system of 'self'.
'Self', like the whirlpool, is held in place by a static (more or less) force and is the result of the physical shape of the space it occupies and the flow of energy that constantly runs through it.
Now this aspect of existence can be thought of as a 'wave-function' that is 'applied' to 'events' that occur in the region of space occupied by self.
But look at the fine structure. If you were to take two snapshots of any region of a whirlpool with an arbitrarily short time between them, you would see two completely different sets of events. And given a number of such pairs that had been mixed up, I think it would be impossible to restore the pairings by sight.
The water in the whirlpool is not the whirlpool itself. The whirlpool simply effects the behaviour of the water as it passes through.
It is the same with 'self', at a fine structure level, any two snapshots of 'self' will be comprised of two completely different sets of events, like snowflakes, no two 'selfs' are identical.
Another feature of whirlpools at finer structure levels is the existence of whirlpools within and upon other countless smaller whirlpool, each of which contribute to the 'eddy currents' that become manifest and which evlve over time.
If a whirlpool could examine its own state, it would find a historical record of its existence.
'Self' can examine its own state. At any one time, 'self' has access to the history of 'self'. When we 'recall' the past, we are in effect examining a 'look-up table' that previous 'selfs' have appending at each point in time.
Each 'self' superimposes its own pattern on the space it occupies.
I think what Morbet is saying can be accepted as a starting point for the question of motion. I mean, if time-slicing, etc., can be used as an effective means of thinking of the universe then you, we even, can try to expose problems fundamental to the issue.
For example, suppose it was a feature of each time-slice such that the emission or absorption of a photon occurs in a single slice. I.e. that in say the process of an electron absorbing a photon, moving to its new position and then emitting a new photon would happen in three discrete events seperated into three slices, one slice with the photon about to be absorbed, one slice with an over-excited electron and on slice with a stable electron and a new photon. We could then say that the speed of light may be limited due to the 'decision-making time' of a photon.
This would work as a start point for me. There may be 'particles' that think faster than photons can but let's leave them for now.
Slicing up the universe does provide elegant ways of looking at things but still leaves room for questions.
My question would be about directionality. It's two questions really.
Direction has an apparent effect. The direction and the speed of an electron can either red-shift or blue-shift an incoming photon.
If a time-sliced electron is a single set of events, how does it know its momentum and direction? An electron is an electron is an electron, isn't it?
How does the electron arrive at the right result, how does it calculate how much energy to take from the absorbed photon? It is as if the electron knows to treat the photon as if it is at a different energy level to its actual starting level.
If motion doesn't exist then how could photon interactions occur as if it does? Why should red-shift or blue-shift happen at all?
I guess I'm asking, What could give rise to the property of 'direction' and ultimately, to speed and momentum? I just don't see how time-slicing can yield an explanation for the effects of relative motion without accounting for something that is in motion.
Then there's expansion.
When a photon from a distant galaxy sets out towards us it is at a distance 'x'. Without expansion we can come up with a total distance that the photon has to travel.
However, due to expansion, the photon may have to travel twice that distance. This would suggest that new time-slices are being created as the photon travels, being placed 'in front of' and 'behind' it all the way along its journey and at a certain rate.
If all time-slices exist simultaneously, why should the distance the photon needs to travel increase over time? And again, upon absorption, why would it appear red-shifted?
This static 4-D cube just keeps increasing in volume. Something is moving.
Surely?0 -
I know you're not explicitly saying it, but you are tacitly assuming it.Nobody is saying you got from that you to this you. You're not treating time consistently. I am instead saying the "yet here I am" you has memories of the "9:05" you, and all "yous" in between.
The 09:05 me was a self-perception event, which was frozen in my worldline; my experience of the narrative of my worldline should not have gone beyond that; because "I" am, or at least, according to the worldtube interpretation, "I" am just a single event frozen on the overall "roosh" worldtube; the 3D version of roosh that "I" experience, in the observable world, should not have experienced anything beyond 09:05.
You're taking a subsequent self-perception event to explain why the experience hasn't been frozen at 09:05, but you are required to explain how we get from 09:05 me to "yet here I am" me.
Again, bear in mind that "I" am just a single, self-perception event frozen on a worldtube; so my experience of the observable world should be limited to that single event and the memories that precede it - although that in itself is being very generous given the duration of a memory and how that would correspond to events on a worldtube.
You are required to explain why my experience of the observable world isn't frozen at that time of 09:05; without using any subsequent self events, to which "I" have no access.0 -
You are required to explain why my experience of the observable world isn't frozen at that time of 09:05; without using any subsequent self events, to which "I" have no access.
You have to explain why spacetime would imply your experience of the observable world would be frozen at 9:05.0 -
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This has already been explained I think.You have to explain why spacetime would imply your experience of the observable world would be frozen at 9:05.
We might be experiencing an issue with language here, becuase when we use the term "you" or "me" it might be confusing the issue; this is because we, supposedly, have the worldtube of "you" as well as the 3D manifestation of "you" which is just a point on the overall worldtube. For this reason it might be helpful to distinguish between "you" and "me" as the 3D manifestations of the, supposed, points on a worldtube, and the "your tube" and "my tube".
So we are looking for an explanation of why the observable world should be frozen for "me" [the 3D manifestation of a supposed point on a 4D worldtube]. The reason is that the points on a worldtube are themselves stuck, they are frozen on the worldtube; they don't advance and there's no moment to moment transition. The manifestation of the 3D world which I (or "me") experience(s), along with "me" is, supposedly, just a point on 4D worldtube; again, there is no moment to moment transition and the points are fixed (frozen) along the worldtube.
As it is the 3D world that we experience, it is in the 3D world that we have our moments of "self-identification"; given that those moments are frozen on a worldtube we, that is "you" and "me" should be frozen in those moments of self-identification. That includes the neurons in our brain, which affects the memories that we recall, as well as what we observe in the "outside" 3D world, including the clock at 9:05.
Now, you might try to say that "we" are frozen in that moment of self-identification, but that would just be another conclusion that we would have to assume.
The empirical evidence, without any assumptions, points to the fact that there is an ever changing present moment. You might again point to the "mysterious dynamics" as an assumption, but that isn't necessarily the case; the "mysterious dynamics" is the conclusion we arrive at when we drop the assumptions of "past" and "future".0 -
This has already been explained I think.
We might be experiencing an issue with language here, becuase when we use the term "you" or "me" it might be confusing the issue; this is because we, supposedly, have the worldtube of "you" as well as the 3D manifestation of "you" which is just a point on the overall worldtube. For this reason it might be helpful to distinguish between "you" and "me" as the 3D manifestations of the, supposed, points on a worldtube, and the "your tube" and "my tube".
So we are looking for an explanation of why the observable world should be frozen for "me" [the 3D manifestation of a supposed point on a 4D worldtube]. The reason is that the points on a worldtube are themselves stuck, they are frozen on the worldtube; they don't advance and there's no moment to moment transition. The manifestation of the 3D world which I (or "me") experience(s), along with "me" is, supposedly, just a point on 4D worldtube; again, there is no moment to moment transition and the points are fixed (frozen) along the worldtube.
As it is the 3D world that we experience, it is in the 3D world that we have our moments of "self-identification"; given that those moments are frozen on a worldtube we, that is "you" and "me" should be frozen in those moments of self-identification. That includes the neurons in our brain, which affects the memories that we recall, as well as what we observe in the "outside" 3D world, including the clock at 9:05.
Now, you might try to say that "we" are frozen in that moment of self-identification,but that would just be another conclusion that we would have to assume..
The empirical evidence, without any assumptions, points to the fact that there is an ever changing present moment. You might again point to the "mysterious dynamics" as an assumption, but that isn't necessarily the case; the "mysterious dynamics" is the conclusion we arrive at when we drop the assumptions of "past" and "future".
You've answered your own objection in blue. But your incorrect statement in red has hidden the answer from yourself.
We have previously established that the issue is an ontological one, and not an empirical one. We have mathematical descriptions that accurately predicts phenomena. The equivalent descriptions do not insist on any particular metaphysics. If it truly were an empirical issue, then science would come down on one side or the other. This is concisely described in one of Richard Feynmann's lectures (Watch it from 33:28 to 39:30)
http://www.youtube.com/watch?v=kd0xTfdt6qw&t=33m28s
So the dynamical interpretation is the conclusion we arrive at when we drop the assumption of a block universe. Similarly, the block universe is a conclusion we arrive at when we drop the assumption of dynamical relativity. These are philosophical differences, not empirical ones.0 -
Dynamical relativity isn't the assumption, it's the conclusion; as said, the "mysterious dynamics" is the conclusion arrived at when we drop the assumptions of "past" and "future", or rather, if we don't pick them up in the first place.You've answered your own objection in blue. But your incorrect statement in red has hidden the answer from yourself.
We have previously established that the issue is an ontological one, and not an empirical one. We have mathematical descriptions that accurately predicts phenomena. The equivalent descriptions do not insist on any particular metaphysics. If it truly were an empirical issue, then science would come down on one side or the other. This is concisely described in one of Richard Feynmann's lectures (Watch it from 33:28 to 39:30)
http://www.youtube.com/watch?v=kd0xTfdt6qw&t=33m28s
So the dynamical interpretation is the conclusion we arrive at when we drop the assumption of a block universe. Similarly, the block universe is a conclusion we arrive at when we drop the assumption of dynamical relativity. These are philosophical differences, not empirical ones.
But that still doesn't resolve the issue of being frozen at a given point in "time", or account for relative motion in a block universe.
"You" and "me", as in the 3D manifestations of the supposed 4D worldtube, the incidents of "self-identification", are points frozen on the worldtube; that is, the moment of self-identification at 9:05 is a point frozen on the worldtube. As points on a worldtube, we don't have access to any other points along the worldtube, particularly later points. The neurons in our brain are in a frozen state also, which affects the duration of any memories we might have at a given point and the amount of relative motion we might perceive as a result.
It might be helpful to think in terms of a roll of film, which is shot at the given rate of frames per second, where "you" and "me" are confined to a single frame, which represents a moment of self-identification. Each frame can only remember the frame immediately preceding it - that is allowing for the duration of a memory permitted by the neurons frozen in each frame. Now, imagine that in one of those frames the clock reads 9:05 and the scenery is frozen, as in a frame on a roll of film. In the previous frame the clock also read 9:05 and the scene was frozen but with the tiniest of differences from the next frame. Each frame represents a moment of self-identification and your and my experience of the 3D world as "you" and "me". Our experience of the 3D world should therefore be limited to one of these frames and an almost imperceptible amount of relative motion. Our experience of the 3D world should not go beyond the clock at 9:05.0 -
Dynamical relativity isn't the assumption, it's the conclusion; as said, the "mysterious dynamics" is the conclusion arrived at when we drop the assumptions of "past" and "future", or rather, if we don't pick them up in the first place.
No offence but that is an absolutely ridiculous statement. The conclusion that the past and future exist is physically equivalent to the conclusion that mysterious dynamics exist. This is basic philosophy 101.But that still doesn't resolve the issue of being frozen at a given point in "time", or account for relative motion in a block universe.
"You" and "me", as in the 3D manifestations of the supposed 4D worldtube, the incidents of "self-identification", are points frozen on the worldtube; that is, the moment of self-identification at 9:05 is a point frozen on the worldtube. As points on a worldtube, we don't have access to any other points along the worldtube, particularly later points. The neurons in our brain are in a frozen state also, which affects the duration of any memories we might have at a given point and the amount of relative motion we might perceive as a result.
It might be helpful to think in terms of a roll of film, which is shot at the given rate of frames per second, where "you" and "me" are confined to a single frame, which represents a moment of self-identification. Each frame can only remember the frame immediately preceding it - that is allowing for the duration of a memory permitted by the neurons frozen in each frame. Now, imagine that in one of those frames the clock reads 9:05 and the scenery is frozen, as in a frame on a roll of film. In the previous frame the clock also read 9:05 and the scene was frozen but with the tiniest of differences from the next frame. Each frame represents a moment of self-identification and your and my experience of the 3D world as "you" and "me". Our experience of the 3D world should therefore be limited to one of these frames and an almost imperceptible amount of relative motion. Our experience of the 3D world should not go beyond the clock at 9:05.
Not only is this wrong for the reasons I mentioned in previous posts, but you are now bringing in nonsense about non-standard infinitesimals.0 -
The experimental evidence indicates that the measurement of the speed of light is constant. You are saying that for the results to be compatible with presentism, the conclusion we would reach would be that "mysterious dynamics" are at play. We wouldn't have to assume that "mysterious dynamics" are at play, it would be the only conclusion. The issue is then a question of whether or not presentism is as much an assumption as the existence of past and future. It isn't, however, because presentism is simply the lack of assumptions about the existence of past and future.No offence but that is an absolutely ridiculous statement. The conclusion that the past and future exist is physically equivalent to the conclusion that mysterious dynamics exist. This is basic philosophy 101.
What do you mean by "non-standard infinitesimals"Not only is this wrong for the reasons I mentioned in previous posts, but you are now bringing in nonsense about non-standard infinitesimals.
The reasons you've used before relied on using later frames, or later incidents of self-identification, to try explain the issue, but our experience of the 3D world should be limited to a single frame or moment of self-identification, because those moments are frozen on the worldtube. At best we would observe an incredibly small amount of relative motion with the question being how that observation would play out in a single frame; is there a sequential ordering between the memory and the observation in the present moment? Either way our experience of the 3D world should not advance beyond the clock at 9:05, without some mechanism for a transition to the next moment.0 -
The experimental evidence indicates that the measurement of the speed of light is constant. You are saying that for the results to be compatible with presentism, the conclusion we would reach would be that "mysterious dynamics" are at play. We wouldn't have to assume that "mysterious dynamics" are at play, it would be the only conclusion. The issue is then a question of whether or not presentism is as much an assumption as the existence of past and future. It isn't, however, because presentism is simply the lack of assumptions about the existence of past and future.
Now you are just swapping the conclusion and the assumption around. I.e. You are assuming presentism is true.What do you mean by "non-standard infinitesimals"
http://en.wikipedia.org/wiki/Non-standard_analysisThe reasons you've used before relied on using later frames, or later incidents of self-identification, to try explain the issue, but our experience of the 3D world should be limited to a single frame or moment of self-identification, because those moments are frozen on the worldtube. At best we would observe an incredibly small amount of relative motion with the question being how that observation would play out in a single frame; is there a sequential ordering between the memory and the observation in the present moment? Either way our experience of the 3D world should not advance beyond the clock at 9:05, without some mechanism for a transition to the next moment.
As you said yourself, a moment is not sufficient for self-identification. Self-identification occurs in the context of several moments.0 -
The issue
Thanks for the detailed reply masteroid; I understand the points you are making, but the causal relationship between events isn't the issue in question. The basic question is, what causes relative motion? I am suggesting that only absolute motion can account for relative motion.
I think this is quite obvious really. For any object to move relative to any other object, at least one of them has to have moved in absolute terms. If it had not then the relative positioning has to remain the same. Surely that's a black and white argument?
One question i have regarding motion though. Assuming that only the present moment exists (or at least exists for anyone in that moment) Is anything actually moving at all? Yes things obviously move with reference to the past and we can predict their movements into the future, but for us the observer, these things don't really exist in the physical sense - we have records of the past, memories, photos and so on and we have ideas of the future (when fabregas kicks the ball, we assume it's going to rocket towards the goal) In reality the past is gone to us, we can never physically inhabit it again and the future while usually predictable could surprise us - some bizarre new force, or outside influence could come into existence and change the ball somehow, meaning fabregas bounces off it and not the other way round - highly unlikely, but theoretically possible.
Is the only thing we know for an absolute certainty, that which we observe at the exact instant we observe it? - That is a snapshot, a still frame. So is what we are seeing an illusion, like a movie, ever changing stills that our minds trick us into percieving as motion.
It seems to me that there has to be a clear distintction between that which exists and that which doesn't, i just can't see how the past or the future can "physically" exist. They are obviously there as memories of the past and possibilities of the future, but as actual flesh and blood physical realities? I just can't see how they could be.0 -
Every observer, anywhere, only ever experiences the present moment; that is the most fundamental empirical observation we can make. Anything other than presentism requires an assumption on behalf of every observer in the universe, that the past and/or future exists. Presentism is simply the absence of these assumptions. In the absence of these assumptions, the conclusion we arrive at is the so-called "mysterious dynamics".Now you are just swapping the conclusion and the assumption around. I.e. You are assuming presentism is true.
I don't think we need the non-standard infinitesimals. We only need to consider the fact that each moment is frozen on the worldtube; either way, our experience of the 3D world should not extend beyond the clock at 9:05.
I think it was yourself who introduced the term "self-identification". That just further compounds the issue, given that each moment is represented by a separate point along a worldtube; we should not have any experience "self-identification", because we are the 3D manifestation of a single moment on a worldtube; if several moments are required then we again need some process of moment to moment transition for "self-identfication" to be possible.As you said yourself, a moment is not sufficient for self-identification. Self-identification occurs in the context of several moments.
Just to re-iterate, as a 3D manifestation exisitng on a 4D worldtube, "we" should be nothing more than a static point on a worldtube, with no moment to moment transition. Whatever time is on your clock now, your experience of the 3D world should not extend beyond that - without some mechanism for transition.0 -
That would be my thinking. The alternative appears to be the block universe, but the contention is that relative motion would not arise in a block universe.sbsquarepants wrote: »I think this is quite obvious really. For any object to move relative to any other object, at least one of them has to have moved in absolute terms. If it had not then the relative positioning has to remain the same. Surely that's a black and white argument?
One sense in which "the past" and "future" physically exist, which is not in the sense of the block universe, where "the past" is still physically manifest or observable somewhere or somewhen, is as follows:sbsquarepants wrote: »One question i have regarding motion though. Assuming that only the present moment exists (or at least exists for anyone in that moment) Is anything actually moving at all? Yes things obviously move with reference to the past and we can predict their movements into the future, but for us the observer, these things don't really exist in the physical sense - we have records of the past, memories, photos and so on and we have ideas of the future (when fabregas kicks the ball, we assume it's going to rocket towards the goal) In reality the past is gone to us, we can never physically inhabit it again and the future while usually predictable could surprise us - some bizarre new force, or outside influence could come into existence and change the ball somehow, meaning fabregas bounces off it and not the other way round - highly unlikely, but theoretically possible.
Is the only thing we know for an absolute certainty, that which we observe at the exact instant we observe it? - That is a snapshot, a still frame. So is what we are seeing an illusion, like a movie, ever changing stills that our minds trick us into percieving as motion.
It seems to me that there has to be a clear distintction between that which exists and that which doesn't, i just can't see how the past or the future can "physically" exist. They are obviously there as memories of the past and possibilities of the future, but as actual flesh and blood physical realities? I just can't see how they could be.
If we imagine the ingredients for a cake:
Eggs
Flour
Water
Milk
Cocoa
Sugar
etc.
Imagine them sitting on the counter before we make the cake; the eggs in their shells, the milk in the carton and so on. Then we set about making dough or mix, which will be baked into a cake; the eggs, flour, water, sugar, cocoa, etc. are mixed all together; the packaging is discarded in the bin and the ingredients look like a big ball of dough (or whatever it is). The dough is put in a baking dish and baked in the oven.
When the cake comes out of the oven, nicely baked, we might say that the eggs no longer exist, that the milk no longer exists, that the ingredients no longer exist, but that, strictly speaking, isn't true; all the ingredients still exist, they just exist in a different form. The shells of the eggs are in the bin, and the eggs, along with all the other ingredients are in the cake. The ingredients in their previous form are no longer manifest, but everything still exists. The same is true of the future; everything that will manifest in the future already exists in the present, just in a different form.0 -
I'm not sure what you mean by block universe, i haven't heard the term before (i've just skimmed this thread, i'm in work at the moment!).
In the cake analogy, i do see what you mean, but i'd have to argue that the ingredients no longer exist in any real sense, any more than i'm a billions of years old star - the elements i'm built from were fused in long dead stars billions of years ago - but that's not the same thing, that star no longer exists as a star and whatever tiny percentage of it (or most likely them) is now "me" is irrelevant. The eggs and flour and so on don't exist anymore than my star does. They are just memories.0 -
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The block universe is a concept that often gets portraryed as a necessary conclusion of Einsteinian relativity; it's essentially the physical structure where past, present, and future co-exist together. In a basic analogy it is likened to a loaf of bread, where one slice of the loaf represents an observers present moment.sbsquarepants wrote: »I'm not sure what you mean by block universe, i haven't heard the term before (i've just skimmed this thread, i'm in work at the moment!).
I also see what you mean with that, and I would agree in a sense; what we are getting down to here is concepts and how they apply to the physical world. It's an interesting point, I believe, because it's quite similar to some of the things that are said in Buddhist philosophy.sbsquarepants wrote: »In the cake analogy, i do see what you mean, but i'd have to argue that the ingredients no longer exist in any real sense, any more than i'm a billions of years old star - the elements i'm built from were fused in long dead stars billions of years ago - but that's not the same thing, that star no longer exists as a star and whatever tiny percentage of it (or most likely them) is now "me" is irrelevant. The eggs and flour and so on don't exist anymore than my star does. They are just memories.
It might be useful to look at water, first. Usually when we think of water, we think of the liquid form; if we say a glass of water we invariably mean the liquid form. I think we tend to be a bit more familiar with the idea that ice is just another form of water, but we still distinguish ice from water; if we ask for a glass of ice we have a very different expectation of what we will receive if we ask for a glass of water; to the extent that, conceptually, at least, we are saying that ice is not water. The same is true of steam; we would, of course, never ask for a glass of steam, but we certainly think of steam being something different from ice and water. But, as mentioned, I think we tend to be a bit more familiar with the idea that they are just different states of the same thing; we apply conceptual labels to them to differentiate the different states, but they are essentially just the same thing.
The same is true of the ingredients, except we have the complication of mixing the ingredients together, such that we are no longer dealing with different states of the same thing, but different states of different things when they get mixed together. So the ingredients still exist in their entirety, they just exist in different forms, and the conceptual lables we applied to the ingredients before mixing no longer apply, but the things still exist*.
The same would be true of us and the stars; we are not "stars" in terms of the conceptual labels, but what constituted a "star" also constitutes "us" and other things around us. It's a bit like saying that my "foot" is not my "hand", but if you start at your finger tips and move your finger down to the ball of your hand, at the base of the palm, there is no actual point where your hand ends and your wrist begins, just as there is no point where your writst ends and your forearm begings; we can follow this all the way down to the "foot" and see that there's no point at which the hand and the foot are actually separate.
Apologies, I went off on a bit of a tangent there!
*without getting into a discussion on the nature of existence.0 -
Every observer, anywhere, only ever experiences the present moment; that is the most fundamental empirical observation we can make. Anything other than presentism requires an assumption on behalf of every observer in the universe, that the past and/or future exists. Presentism is simply the absence of these assumptions. In the absence of these assumptions, the conclusion we arrive at is the so-called "mysterious dynamics".
What you are assuming is that every observer's physical moment is the same. Plus, again, you are simply juggling assumptions. I could just as easily say the block universe is the conclusion we arrive at in the absence of assumptions about hidden dynamics.I don't think we need the non-standard infinitesimals. We only need to consider the fact that each moment is frozen on the worldtube; either way, our experience of the 3D world should not extend beyond the clock at 9:05.
Then I simply refer you to my previous post: Any given moment does not extend temporally. But the collection of all moments contains all clock strikes. And the thermodynamic structure of the universe gives us awareness of events in one direction but not the other.I think it was yourself who introduced the term "self-identification". That just further compounds the issue, given that each moment is represented by a separate point along a worldtube; we should not have any experience "self-identification", because we are the 3D manifestation of a single moment on a worldtube; if several moments are required then we again need some process of moment to moment transition for "self-identfication" to be possible.
Just to re-iterate, as a 3D manifestation exisitng on a 4D worldtube, "we" should be nothing more than a static point on a worldtube, with no moment to moment transition. Whatever time is on your clock now, your experience of the 3D world should not extend beyond that - without some mechanism for transition.
And I will reiterate my response: Nobody is supposing a transition from one moment to the next. According to the block universe, all moments exist atemporally, and their structure gives rise to the experience of passing from one moment to the next, and of remembering the past but not the future.0 -
There is no assumption that every observer's physical moment is the same. Every observer only ever experiences the present moment; for presentism to not be true it means that every observer's past and/or future must physically exist; this requires an assumption on behalf of every single observer that this is the case. Presentism is simply what is left when observers don't make these assumptions. Without these assumptions the conclusion is a set of dynamics that we don't yet understand. We don't assume the hidden dynamics, the empirical evidence points to that conclusion, if we simply drop the assumptions about past and future.What you are assuming is that every observer's physical moment is the same. Plus, again, you are simply juggling assumptions. I could just as easily say the block universe is the conclusion we arrive at in the absence of assumptions about hidden dynamics.
Every moment doesn't need to extend temporally, that is partly the point; every moment is a point, or section, frozen on a world tube, where each moment can correspond to a reading on a clock. We can liken those moments to frames on a reel of film, where the still scene is captured in the frame, with the reading on the clock. Regardless of what we can remember of the past, our experience of the 3D world should not extend beyond the time reading on the clock in our particular frame.Then I simply refer you to my previous post: Any given moment does not extend temporally. But the collection of all moments contains all clock strikes. And the thermodynamic structure of the universe gives us awareness of events in one direction but not the other.
You mention that the thermodynamic structure of the universe gives us awareness of events in one direction, but not the other, but you fail to mention how it does this. I think, however, this is no different to the point you've been making all along about conscious memory of previous moments is how we perceive relative motion; it still doesn't address the fact that the 3D manifestation of ourselves, in a given moment, is frozen on a worldtube, it doesn't advance and there is no moment to moment transition; therefore, our experience of the 3D world should not extend beyond any given time reading on our clock; like the time of 9:05 we had been discussing.
The is the point of contention, however, namely that the structure of worldtubes and the block universe can't account for our experience of the 3D world. At best it might account for a miniscule observation of relative motion, but even that would require further investigation. The structure of worldtubes in a block universe means that our experience of the 3D world should not extend beyond a specific time reading on our clocks, because each moment is fixed on the worldtube.And I will reiterate my response: Nobody is supposing a transition from one moment to the next. According to the block universe, all moments exist atemporally, and their structure gives rise to the experience of passing from one moment to the next, and of remembering the past but not the future.0 -
The block universe is a concept that often gets portraryed as a necessary conclusion of Einsteinian relativity; it's essentially the physical structure where past, present, and future co-exist together. In a basic analogy it is likened to a loaf of bread, where one slice of the loaf represents an observers present moment.
Might be going slightly off topic here, but then the question arises of how thin the slices are. By that i mean how divisible is time, we know that matter is not infinitely divisible, you eventually get down to fundamental particles - we are almost certain we know what they are at this stage. It seems likely to me that if time is an actual physical thing, rather than a mere construct to help our minds make sense of our journey through the universe, then it would likely be constructed similarly, out of similar "lego" for want of a better word. If it can be infinitely divided, it's probably not a real physical "thing".
Also, definitely going off topic here, but if indeed, the future already exists, i assume that means it is set in stone, everything is already predetermined? I have already lived my life, died and so on, the "me" typing here just hasn't got to that particular stop on the cosmic bus route yet?
I can't decide if i find that comforting or depressing.:eek:0 -
There is no assumption that every observer's physical moment is the same. Every observer only ever experiences the present moment; for presentism to not be true it means that every observer's past and/or future must physically exist; this requires an assumption on behalf of every single observer that this is the case. Presentism is simply what is left when observers don't make these assumptions. Without these assumptions the conclusion is a set of dynamics that we don't yet understand. We don't assume the hidden dynamics, the empirical evidence points to that conclusion, if we simply drop the assumptions about past and future.
You're still chasing your own tail. You have also, again, strayed into a line of thinking that not even presentists would adopt. If it were an empirical issue, scientists would all be presentists. Scientists are not presentists.
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The same thing is happening that has happened before. You are ultimately repeating yourself. I am fine by that. If attrition is what is needed, then so be it. But new issues are popping up in parallel. So until we sort out the "empirical" issue above, I am putting aside the issue of interpreting the worldline. Once the above issue is sorted, we can return to it. Otherwise the thread will simply continue to branch into a fractal mess of issues.0 -
sbsquarepants wrote: »Might be going slightly off topic here, but then the question arises of how thin the slices are. By that i mean how divisible is time, we know that matter is not infinitely divisible, you eventually get down to fundamental particles - we are almost certain we know what they are at this stage. It seems likely to me that if time is an actual physical thing, rather than a mere construct to help our minds make sense of our journey through the universe, then it would likely be constructed similarly, out of similar "lego" for want of a better word. If it can be infinitely divided, it's probably not a real physical "thing".
Also, definitely going off topic here, but if indeed, the future already exists, i assume that means it is set in stone, everything is already predetermined? I have already lived my life, died and so on, the "me" typing here just hasn't got to that particular stop on the cosmic bus route yet?
I can't decide if i find that comforting or depressing.:eek:
The temporal "thickness" of a slice would be 0. Spacetime is what is known as a manifold. It is a continuum of slices (Hence the Star Trek phrase "spacetime continuum"). From the wikipedia article:
"By combining space and time into a single manifold, physicists have significantly simplified a large number of physical theories, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels."0 -
Cheers Morbert - your post has led me to some fascinating articles (not much work done today:D) I wonder if the boss would go for the "it's all predetermined" excuse.
I have to say though, i have somewhat of a problem with the concept of an eternaly divisible physical dimension. It just seems logical to me that if you keep cutting something in half you will eventually get to a point where it just can't be cut again, you will reach it's fundamental building block. Surely if it (ie time) physically exists it must be made from something?0 -
sbsquarepants wrote: »Cheers Morbert - your post has led me to some fascinating articles (not much work done today:D) I wonder if the boss would go for the "it's all predetermined" excuse.
I have to say though, i have somewhat of a problem with the concept of an eternaly divisible physical dimension. It just seems logical to me that if you keep cutting something in half you will eventually get to a point where it just can't be cut again, you will reach it's fundamental building block. Surely if it (ie time) physically exists it must be made from something?
The structure of spacetime at the small scale (specifically the planck scale) is an open issue for physicists, but for reasons to do with quantum mechanics rather than inherent logical inconsistencies. Basically, for any definition of the "smallest" time interval, I could suppose an interval half that size.
Numbers have a similar property. For any number x that is greater than 0, I can give you a number y that is less than x but greater than 0.0 -
I understand what you're saying, but numbers are just ideas - they aren't physical "things". If you take the example of a planck length, physically it may well be some fundamental limit (or it may not, i don't know), but as merely a number there is no problem with dividing it in 2 or in 2 billion, it's mere concepts. It's only when you try to relate that to a physical thing you run into problems. A measuring system for quantifying distance is not the same thing as physical space.
Same thing with time - we can divide a second into ever smaller segments but a second is not actual time, it's merely a representation of time, an agreed upon number of swings of a pendulum or vibrations of a quartz crystal, nothing more.0 -
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sbsquarepants wrote: »I understand what you're saying, but numbers are just ideas - they aren't physical "things". If you take the example of a planck length, physically it may well be some fundamental limit (or it may not, i don't know), but as merely a number there is no problem with dividing it in 2 or in 2 billion, it's mere concepts. It's only when you try to relate that to a physical thing you run into problems. A measuring system for quantifying distance is not the same thing as physical space.
Same thing with time - we can divide a second into ever smaller segments but a second is not actual time, it's merely a representation of time, an agreed upon number of swings of a pendulum or vibrations of a quartz crystal, nothing more.
And a physical spacetime continuum would be no more difficult to divide than a number.0
This discussion has been closed.
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