Is Time Merely Constant Change?

[kvantti]

http://en.wikipedia.org/wiki/Block_time
http://plato.stanford.edu/entries/time/#8

 

[Doctordick]

Kvantti, your references are almost the definition of "thinking inside the box"! To quote:

"For example, special relativity has shown that the concept of 'simultaneity' is not universal"! In actual fact, what is shown is that "simultaneity" can not be defined; a much more stringent impediment to the conventional picture. That is sort of like division by zero which just happens to be the central difficulty (continuity is the other side of the division by zero issue). I am personally of the opinion that the central issue of Zeno's paradox is the impossibility of continuous time being a valid aspect of reality.

"It is uncontroversial that physical objects are typically extended in both space and time." Yes, it is "uncontroversial"; but that, in no sense, can be taken as proof that it is true! Physical objects themselves are mental constructs. A "vehicle", for example, is a category for a particular collection of elemental entities (which are real, or at least presumed to be real), a "bus" may be a vehicle but that does not require all vehicles to be buses. My point being that it is the representation of the information which constitutes a "physical object" and it is the mode of representation (a mental thing) which requires space and time, not reality; all reality requires is the "information" itself. Or I could say reality requires "some" of that information; our mental image of reality fills in the rest. What is, and what is not a figment of our imagination is a question which cannot be settled. In fact, the figments of our imagination change regularly with changes in our explanations of reality; anyone who believes the future will contain no more changes in their fundamental beliefs is without imagination: ninety percent of our lives is lived in superstition even by the most rational of us. (And yes, the "is" is the right case to use there.)

Space and time are mental constructs we create in order to organize our experiences into handleable pieces. There is a division in thought which receives attention far below what is needed. That division can be referenced by the words "deduction" or "induction"; "logical" or "intuitive"; "science" or "superstition"; "thought" or "feeling"... Let us just call them "type A" and "type B" mental activities. All human languages (save mathematics) are based on "type B" mental activities. That's why communication is so difficult! You can not prove the words you use mean the same thing to others as they do to you. Unless they happen to be analytical truths as defined by Kant (analytic propositions are those which are true simply in virtue of their meaning); in that case we either agree with the definition and can use the term to communicate or we disagree and simply are not talking about the same thing.

And finally, roamer, if you have a good understanding of mathematics and logic, I can show you some relationships which must be valid no matter what we know or don't know. If you can understand what an analytical truth is and can follow the logical consequences of my definition of http://home.jam.rr.com/dicksfiles/Explain/Explain.htm , there are a lot of the aspects of reality (anyones reality) which become quite clear.

Have fun -- Dick

 

[AnssiH]

Well, the thing is that relativity strongly implies that time does not tick away but that future and the past exist all the time. So that's what I was talking about in the other thread.

I have heard people talking about how everything is happening at once. That is interesting. Do you know where I can ontain more information about this
RAD

Looks like Kvantti already posted some links.

Few words still; it would be wrong to say "everything is happening at once" because just the word "happening" implies motion. We should say "everything exists at once". May sound like splitting hair, but it's too easy to confuse the idea of motion to spacetime and I see people doing it far too regularly without realizing it.

And why relativity implies static spacetime is that it assumes simultaneity is not absolute but it is relative to your direction of motion (and by this assumption we can assert that the speed of light is the same to all observers). This is the basic building block of relativity and needs to be understood properly.

Thought experiment; let's say there is a spaceship approaching us at great speed. By assuming the light is approaching us at speed C, we can figure out what is the "real" moment when the spaceship is just passing Alpha Centauri, assuming it is moving at a steady speed. We decide to put up a signal beacon at the same moment.

Now, SR says the moment we put up the beacon and the moment the spaceship passes Alpha Centauri are not "really" simultaneous in any inertial frame but in our. When the spaceship receives a signal from our beacon, it can figure out when did the beacon go up, and assuming the speed of light to be C in its own inertial frame, it will conclude that the beacon went up much much earlier than when it was passing Alpha Centauri.

This means that when the spaceship had not yet even passed Alpha Centauri in your frame, in its own frame you had already put up the beacon long time ago; your future had already happened I.e. your actions are deterministic since they have already happened from the point of view of many inertial frames. (Determinism is not problematic part though; it is not particularly hard to show that the idea about free-will is nonsensical anyway)

It also means that if the spaceship now accelerates (brakes) to the same direction of motion where you are, it will come to share the simultaneity with you. For example, if in its original frame you had put up the beacon three weeks before it reached Alpha Centauri, then when it brakes, the clocks and everything on Earth rewind back to the moment when you were just putting up the beacon.

But this doesn't really make sense as is, so if you assume simultaneity to really be relative, you will also feel strong need to assume reality is a spacetime where future and past actually exist all the time; that "time is just an illusion".

It would also mean that time exists as a real dimension in which all the events that ever happened and will ever happen are marked. And in this spacetime NOTHING could actually move. If you assume time "causes" motion, and you assume any motion in spacetime, you also need to assume a new time dimension which causes/describes the motion inside spacetime, and this leads to infinite regress. If you are not convinced of this, please think more.

So I hope now everybody have some idea about why relativity strongly suggests static spacetime.

And the reason I say "strongly" is that relativity doesn't allow for any direct observation of the relativity of simultaneity. We cannot actually see the clocks moving backwards or anything like that. Strictly speaking, what we can measure is that different objects move at different rates in different situations, and this doesn't actually require that future and past exists all the time; ALL the observable effects of relativity could work by universal notion of simultaneity, but to describe the reality this way would not be "geometrically simple" the way that SR is simple.

However, read on...

The problem here is that most all of you have made no real effort to understand what "time" is all about (and I include most all scientists in that category).

Spot on. And I had almost lost all hope already. I keep hearing these unthoughtful claims about how "motion could not exist without time" and all sorts of ideas that mix up the concepts of motion and time into incoherent whole, and it's just driving me insane...

"Motion could not exist without time" is simply invalid assertion. Of course it could exist without time; motion could be fundamental feature of nature! It is not in any sense "more likely" that time is what is fundamental instead of motion. One needs to understand how we understand the world. We create semantical assumptions and concepts about what we observe, and by observing motion, we can derive the semantical concept of time! When we say "It takes 60 seconds to boil water" we are saying "by the time the little hand on the clock has done full circle, the water is boiling". This is nothing but a comparison of TWO MOTIONS.

Just like in a universe with just one object there is no "speed" for the object to measure, so there is no "time" for it to measure. There is no backdrop called "empty space", this is a figment of imagination. Similarly, we cannot measure time itself. That's right, time cannot be measured. We cannot claim that "time" moves at certain speed at all. If you feel the need to reply "I measure time with my wristwatch all the time", think more.

Few words about one particularly interesting case of "mixing up concepts incoherently". It is asserted that spacetime was created in the big bang 15 billion years ago (give or take some). If this sounds unproblematic idea, think more.

Imagine a 3D-block. Let's say this is the whole reality for 2 space dimensions and 1 time dimension. At the bottom parts we have the "past" and at the top the "future" (=entropy increases upwards).

When we imagine the moment when this spacetime is created, it would be immediately wrong to imagine that it starts to grow from the bottom; this growing would require motion to exist (instead of time). No, the creation event is just one "pop" and the whole thing comes to exist in a static sense, with the beginning, the middle and the end.

Except that even a concept of this "popping" event is something that makes sense only inside spacetime, not outside. We can only say something pops into existence if there is real motion and evolution to a system. When we say the spacetime was created 15 billion years ago, we are saying that at the bottom of the spacetime there is an event which caused the whole spacetime to "pop" into existence, including that "first" event itself. Think about this for a while. Is this very clever idea?

The original assertion was made by extrapolating the expansion of the universe backwards in time until you get to singularity. At that point you can imagine that the whole spacetime curls into a singularity, only this curling is also motion! You cannot say there existed a time when spacetime was curled into a singularity any more than you could say the spacetime is wiggling around.

This is just one instance that drives me crazy, and I'm almost certain this post will also trigger few replies from people who don't think I understand properly what it means that "spacetime didn't exist before big bang". Please... This is just elementary idea and the issue of time is much deeper than some vague idea about how nothing "is" before big bang.

Oh, and entropy, it's a neat idea and all, but it is becoming more and more difficult concept in my worldview, which is becoming increasingly darwinistic. Super-darwinism I could say. Self-organization does not agree very will with absolute (overall) entropy. Yes, dropping a rock on pavement will cause chaotic heat release, but things also fall into all sorts of stable patterns.

I'm thinking entropy and self-organization could both "really" exist, and that could be why there is a universe in motion but still stable; it could be that it will always stay stable, that there will always be chaotic things getting organized and organized things becoming chaotic. Maybe, just maybe... At any rate, self-organization seems like a good way to understand any system (including the brain).

Anyway, if the post I linked to didn't seem to make sense to you before, perhaps after thinking through this post it makes more sense;
https://www.physicsforums.com/showpost.php?p=1100575&postcount=130
(There is a larger issue with time and motion when you get to the philosophy of mind... If this issue does not exhaust you... think more :)

 

[AnssiH]

Yes exactly Mr. Dick.

I certainly hope people in general either spent more time actually thinking about this thing we call "reality", or alternatively shut the hell up :)

 

[cliowa]

Now that depends upon which you take to be the underlying concept. If you take "time" to be the underlying concept and change is to be defined in terms of time then you have essentially presumed continuity. I my head, taking "change" as the primary concept and defining time in terms of change allows that continuity to be part of your explanation and not a necessary aspect of reality but rather a mental construct used to explain your experiences.

Alright. I could of course also define time in terms of my very special feeling about "quetzcoatl". You obviously feel that there is an advantage when taking change to be more fundamental than time. Why do you think that change is any more fundamental then time? Why would you argue that - as a fundamental - change works better than time?

In my opinion many decisions concering philosophic issues are governed by our quest for comfort. We choose to take some things (observations, conclusions) for granted for the benefit of our own pleasant life. Now I don't mean to go religious, not at all.
So in my opinion one should choose as the underlying notions things which are, in general, intuitively pleasing, as long as this is okay with scientific results. Of course new scientific discoveries will alter our perception and thus our philosophy of the world. But I would still argue, that in science and in "real" life time still plays a dominant role. As I know time is on an equal footing with space, as showed us Einstein, but we still treat time differently from the other spacetime dimensions.

If you understand logic and mathematics, I believe I can put forth some rather convincing evidence that the agreement you require is quite easy to achieve and, in fact, leads directly to exactly the observed relativistic effects.

I'm all set, go ahead!

Best regards...Cliowa

 

[ValenceE]

Hello to all,

I ‘d like to respond to Octel’s thought experiment …

Since, imo, time and our thought processes to explain it, are immaterial, it would still be in existence. It would only be a temporary ‘now’, and in fact would be stopped as it could not be perceived by any thought process, until we all thaw and regain our senses.

Giving it’s suggestive notion back, while asking ourselves “man, what happened ? ..”


VE

 

[kant]

I can no longer see time. All I recognize is the morphing and changing of energies/masses/matters. This concept of time we have is slowly deteriorating from my mind. There is no time, all things are just constantly changing? Nothing ever really leaves us... and nothing is ever really born new in terms of energy. So all that we have is all that we have and it never goes anywhere except for changing into differenent physical, dimensional, and material states? So everything is not really passing... only changing. Time will never leave us, we must learn to leave time.

That is some nice crack you are having. Strong stuff! More of that stuff, and you would be morphing into a butterfly, and fly away like in the red bull commercial.


anyways, Whatever the hell you want to called something, it should have some direct connection to other stuff in the universe to be meaningful. Otherwise, you are delusional. Matter needs to change, and if time is needed, than it is meaningful.

 

[AnssiH]

anyways, Whatever the hell you want to called something, it should have some direct connection to other stuff in the universe to be meaningful. Otherwise, you are delusional. Matter needs to change, and if time is needed, than it is meaningful.

The question of course is "is time needed"? The answer is not simple. But, at least, people need to understand that it is wrong to assert that time is a prerequisite of motion (and I hear that far too often).

Well, I don't want to repeat myself so, post #73

 

[ValenceE]

Hello to all !,

If time is an illusion, then everything is an illusion.

Part of an explanation I could subscribe to, would say that Time came in existence the moment the Big Bang occurred, both emerging from a pre-existing atemporal eternity .



VE

 

[Philocrat]

I can no longer see time. All I recognize is the morphing and changing of energies/masses/matters. This concept of time we have is slowly deteriorating from my mind. There is no time, all things are just constantly changing? Nothing ever really leaves us... and nothing is ever really born new in terms of energy. So all that we have is all that we have and it never goes anywhere except for changing into differenent physical, dimensional, and material states? So everything is not really passing... only changing. Time will never leave us, we must learn to leave time.

The problem with the analysis and understanding of time is that, the quality of what results depends entirely on the quality of the pervceiver. If the human sense of time is illusive, as it is being persistently claimed on this thread, then we must question the human perceiver who labours under it. Much as I say this, we must also acknowledge our ability to make useful predictions and estimates about reality in some of the available chances.

However, a fundamental question now arises as to whether the perveiver is scientifically improveable given that our current 'HUMAN LIFE FORM' appears metaphysically fixed. Can it be scientifically re-engineered? Will this improve the perceiver's habitual resolving of visual perspectives
into sensible forms or wholes?

 

[Doctordick]

You obviously feel that there is an advantage when taking change to be more fundamental than time. Why do you think that change is any more fundamental then time? Why would you argue that - as a fundamental - change works better than time?

The issue is quite simple: the concept “time” requires the concept “change” (without change of some type, time could not be defined); however, the concept “change” does not require the concept “time” (in a circumstance not involving time in any way, we can still talk about “change”). The shape of a tree changes as we consider different planer intersections of a tree. Thus is that we must comprehend the concept of change before we can comprehend the concept of time and this not only makes “change” more fundamental than time but has some very important subtle consequences.

In particular, the ordinary public concept of time is that it is a continuous parameter; however, when it comes to facts, you cannot prove that continuity. All you can really prove is that a change has occurred, not that the system passed through the intermediate states. In my personal opinion, this is exactly the issue of Zeno’s paradox; an issue the scientific community has swept under the rug. That is, change could be real, but time (as conceived) is most definitely a mental construct.

But I would still argue, that in science and in "real" life time still plays a dominant role. As I know time is on an equal footing with space, as showed us Einstein, but we still treat time differently from the other spacetime dimensions.

Are you sure the “other space-time dimensions” are real and not a convenient mental construct?

Have fun -- Dick

 

[The Deceiver]

Paradoxes, Paradoxes, Paradoxes, the contradicatories of two or more interpretations a phenomenon that can be argued to exist or to not exist. Motion is impossible because everything is in constant change, this is because motion can be defined as the change of postion in time, space, or dimension. There is an explanation of what Motion is; a paradox. Since Time exists only with motion and change, time does not exist without them. Since Time relies on a paradox to exist, is it not an illusion? Or better yet a shadow, something that exists, but yet, does not exist. However, all of this is just the perception of an individual's mind, some others might have different perceptions; therefore, those are also true. Relativism in a world built on the shoulders of Socrates. *Laughs* A foundations of shadow holds up only ideals.

 

[cliowa]

The issue is quite simple: the concept “time” requires the concept “change” (without change of some type, time could not be defined); however, the concept “change” does not require the concept “time” (in a circumstance not involving time in any way, we can still talk about “change”).

Well, I don't believe it's all that easy. Defining concepts without invoking our way of perceiving seems a little tricky. To me it seems little helpful talking about general issues like the existence of time without making contact with humans. Don't you feel that way? Questions like "Is there a moon if we don't look at it?" and "Are numbers independent of us humans?" seem profound, but must finally be left unanswered, as we close away our measuring instruments while trying to think about them. For the moon, our mental construct, our choice of convenience is that the moon is still there, even if we don't look. That way it's much easier.

Now, "Change" is a notion for which our perception is central. (Because of our perception, we can feel the change of certain things, but not of all. Maybe other beings have a completely different sense of change.) I think that change also requires the concept of time, because even if we look at spatial change (i.e. if we look at one moment in time), we need time to compare different states (light needs to find its way to our eyes, we need to think and so forth).

The shape of a tree changes as we consider different planer intersections of a tree. Thus is that we must comprehend the concept of change before we can comprehend the concept of time and this not only makes “change” more fundamental than time but has some very important subtle consequences.

I don't think that time and change can be so easily disentangled, as I explained above. We need to give either time or change a general background, which is independent of our perception, and then we can talk about the other.

In particular, the ordinary public concept of time is that it is a continuous parameter; however, when it comes to facts, you cannot prove that continuity.

Well, you can't really prove any basic property of our fundamental notions, right? But do we really need to prove it?

All you can really prove is that a change has occurred, not that the system passed through the intermediate states. In my personal opinion, this is exactly the issue of Zeno’s paradox; an issue the scientific community has swept under the rug.

We can (often) measure those intermediate states with a frequency so high, that time appears continuous to us. From there, it's only a matter of convenience to make time continuous. Mathematically it is obviously by far easier to have continuous, non-discrete variables.

That is, change could be real, but time (as conceived) is most definitely a mental construct.

I can't really follow your argumentation there, doctordick. May I ask whe you would consider something real, as opposed to being "only" a human mental construct?

Are you sure the “other space-time dimensions” are real and not a convenient mental construct?

Again, when is something "real" to you? And, of course, I'm not all that sure about virtually everything, but a good mental construct is all we're longing for, true?

Best regards...Cliowa

 

[SF]

Time is not just a "concept", a hallucination.
It's something measurable, something that obeys certain laws.

How do you explain the phenomenon of time dillation as an illusion?

 

[The Deceiver]

Oh, forgot to complete my defination of motion, sorry, I meant to say that motion the change of position and it only exists if there is a starting point, and since everything is in a state of constant change(which involves motion) the original starting point no longer exists and the relation of positon from the starting is also noexistant, so the motion never happened. A paradox and my apologies

 

[kvantti]

How do you explain the phenomenon of time dillation as an illusion?

This is something I would like to know aswel and yet no one gives a satisfying answer.

 

[AnssiH]

Time is not just a "concept", a hallucination.
It's something measurable, something that obeys certain laws.

How do you explain the phenomenon of time dillation as an illusion?

This was not directed to me but...

Time is a measurable quantity only if you interpret some phenomena that way. It is a semantical concept just like motion is a semantical concept. There is no ready way to choose which one is fundamental, but if you choose motion it tends to clear up some ontological issues elsewhere (like in the philosoply of the mind). Don't get locked up to the idea that time must exist to give rise to motion, because we can also claim that time cannot exist without motion. Neither claim can prove anything about the ontology of time/motion.

To answer your question, when we observe, say, the clocks on satellites moving at faster rate than those on earth, we can equally well claim they move through spacetime in such and such manner (as described by GR), or we can build a model where we say the natural phenomena at the satellites moves at faster rate in the environment where the satellite is in (not feeling any inertia) as compared to that on Earth (where the clocks feel inertial/gravitational acceleration. It is also quite trivial to build models that are almost identical to GR as far as observational phenomena goes)

So, it is possible to build such models in great many flavours, but I think as an answer to your question it suffices if you understand that if any physical motion occurs at different speeds in different environments, we can equally well claim it was because of time dimension or because of how observable motion exists metaphysically.

I don't think this issue can be completely cleared, but let it be said it should serve you well if you don't commit to the idea that time must exist metaphysically and consequently motion does not.

 

[AnssiH]

Oh, forgot to complete my defination of motion, sorry, I meant to say that motion the change of position and it only exists if there is a starting point, and since everything is in a state of constant change(which involves motion) the original starting point no longer exists and the relation of positon from the starting is also noexistant, so the motion never happened. A paradox and my apologies

Yeah, which says that motion through empty space is a non-sensical semantical concept (and also about the nature of inertia in different ontologies).

I suspect the above didn't really say anything to most people participating in this thread, and overall it seems like many people are making assertions without having really grasped what we are debating about.

It is also interesting that in forums about AI and in particular the philosophy of AI, most people seem to be able to much more readily understand this issue. This is clearly because they have been forced to spend some time thinking about how a conception of reality is formed by any natural system.

This debate about whether there is metaphysical time is also similar to the debate of whether there is metaphysical space. I hope the latter issue is somewhat easier for people to grasp since everybody knows about Newtonian relativity of motion. And when you grasp that, try to see how our conception of time is also about relative speeds of things;

https://www.physicsforums.com/showpost.php?p=1125842&postcount=64

 

[Doctordick]

Hi Cliowa, I have been off seeing sights out of touch with the web. I found your post very rational and I would like to respond. If you will allow me, I will comment on the issues you bring up in a different order.

Well, I don't believe it's all that easy. Defining concepts without invoking our way of perceiving seems a little tricky.

Ah, it certainly is; but it needs to be done anyway otherwise we cannot really understand “perception”. (You should set my use of “understand” to be essentially equivalent to “explain”; if you cannot explain something how can you defend the idea that you understand it?) This fact is the central issue behind my work and is exactly why I consider “an explanation” to be the single most important concept to be defined in a scientifically objective attack on explaining anything. It provides a foundation from which all useful concepts must arise.

Again, when is something "real" to you? And, of course, I'm not all that sure about virtually everything, but a good mental construct is all we're longing for, true?

Yes, I would agree; a good mental construct is all one longs for; but, establishing a “good” mental construct would seem to include settling the question, “what is real and what is illusion?” A serious scientist should certainly have some interest in the question.

However, before one can answer that question, one must define what one means by the word “real”. Since our purpose is to determine if our perceptions are real, the definition certainly cannot depend upon our perceptions. I am sure you are well aware of the “solipsist/realist” controversy; the “brain in the vat” or “Matrix” image of one’s perceptions as opposed to the presumption that “what you sees is what is” proposition. Settling this controversy is not a trivial issue. There is no doubt that “illusions” exist as it is quite easy to show some of our perceptions to be erroneous and there exists no known proof that all of our perceptions are not illusions; however, conventional science pretty well relegates “illusion” to parlor games. The scientific presumption is, “if you can’t prove it’s an illusion, it’s real. This approach is clearly a self serving rationalization lacking objectivity.

The only objective scientific attack is to make sure that your approach does not eliminate either possibility. In an objective analysis, only those definitions which are analytical truths should be used in constructing a scientific explanation of anything.

Questions like "Is there a moon if we don't look at it?" and "Are numbers independent of us humans?" seem profound, but must finally be left unanswered, as we close away our measuring instruments while trying to think about them.

Unanswered yes; ignored no. To ignore possible alternate answers to these questions is to presume facts not evident. If your explanation relies on such a thing to be a fact, the fact of that presumption should be kept available through some mechanism: i.e., that the existence of the moon in such a circumstance is not a fact but a mental construct. In my opinion, that issue is the essence of Zeno’s paradox. As Zeno pointed out, proof of such a contention that the tree existed would require an infinite number of observations and “infinite” means the observation can not be made (no matter how many observations you make, you are not finished).

We can (often) measure those intermediate states with a frequency so high, that time appears continuous to us. From there, it's only a matter of convenience to make time continuous. Mathematically it is obviously by far easier to have continuous, non-discrete variables.

Yes, you are quite correct; a mental model with continuous time is much easier to deal with. All I am saying is that it must be kept in mind that one is making a presumption which can not be experimentally verified. That makes it into a wonderful candidate as an illusion. Certainly it is a known illusion when we go to the movies.

Now, "Change" is a notion for which our perception is central. (Because of our perception, we can feel the change of certain things, but not of all. Maybe other beings have a completely different sense of change.) I think that change also requires the concept of time, because even if we look at spatial change (i.e. if we look at one moment in time), we need time to compare different states (light needs to find its way to our eyes, we need to think and so forth).

What you are saying is that we need a parameter to describe these different observations. It is a leap of faith to believe that parameter “is” a continuous entity. To put it another way, to say that it cannot be a discrete index because it makes the mathematics too difficult is not a reason to set the concept of discreet time as wrong (or “unreal”). On the other hand, my paper on explanation gives an excellent reason for letting time be continuous in any physical explanation; because it is most definitely a very useful mental construct.

Well, you can't really prove any basic property of our fundamental notions, right? But do we really need to prove it?

No we don’t need to prove any of concepts are necessarily true but to assume they are may lead to failure to consider alternates which might yield better alignments with our perceptions. You ought to try a careful reading of my paper on explanation.

Have fun -- Dick

 

[vanesch]

If I may add my 2 cents: there are essentially 2 views on the physical concept of time: dynamical and geometrical. Of course, in all physical theories, there is a parameter called "t" or something, which is used to label different events/states/... and which implies an order. But there's also an "x" coordinate in physical theories. We don't put in doubt that the x-coordinate of space just "is" and that all values of "x" have an ontological existence. We could discover regularities as a function of x, (that is, if we knew some a situation at a certain value of x = x0, maybe we could find laws, or regularities, that allowed us to say something about the situation at x1 = x0 + dx), but we wouldn't consider that as a "dynamical law", but just some "symmetry of nature". However, wrt time, we are inclined to give a higher ontological status to a privileged value of the t-parameter, which we call "now" and that, moreover, this privileged value "changes".
The question is: is this changing of this privileged "time" a physical phenomenon, or is it just our subjective perception which "travels through" the different ontological manifestations of t ?
Before relativity, I don't think that the question was really on the order of the day: "time flows", said Newton. This was the dynamical view.

But GR gives us an entirely geometrical picture, of a 4-dimensional "block universe". Nothing "moves" in there, but there can be defined a geometrical coordinate "t" which has a similar status as x, or y or z. In that way, "all values of t" have an equivalent ontological status, and observers are simply "flattened" in the t-direction, and traveling in its sense: that is, they seem to experience an x,y,z slice, and then another x,y,z slice, and still another x,y,z slice... Nevertheless, all these slices have equivalent ontological status, but just one is picked out by the subjective experience of the observer to "be now".
One could imagine other kinds of observers, flattened in, say, the x-direction, which experience y,z,t at their "now" for x, and then at another "now" for x1 = x + dx and so on. Regularities as I talked about initially, in the x-direction, would then be interpreted by the observer as "dynamical laws" (while that observer would "experience" all t-moments simultaneously), instead of "symmetries in the x-direction". Other observers might experience the entire x,y,z,t "at once" and don't see any motion.
This is the geometrical view on time.

Physics doesn't really give us an answer to this question, because in all things physical, t is just a parameter, which can just as well be a "dynamical time", as a "coordinate". It relates events wrt to an observer. It doesn't say whether this observer is "travelling through" a geometrical time, or whether time is a dynamical phenomenon in itself. GR is highly suggestive of the geometrical view, though.

 

[kvantti]

Just to throw in some handy quotes from a SciAm article "That mysterious flow" by Paul Davies [SciAm Special Edition "A matter of Time"]:

The flow of time is unreal, but time itself is as real as space.

-- we do not really observe the passage of time. What we actually observe is that later states of the world differ from earlier states that we still remember. The fact that we remember the past, rather than the future, is an observation not of the passage of time but of the assymmetry of time. Nothing other than a conscious observer registers the flow of time. A clock measures durations between events much as a measuring tape measures distances between places; it does not measure the "speed" with which one moment succeeds another.

Just something to think about and to stir up the conversation.

 

[vanesch]

kvantti: what you quoted is indeed the entirely geometrical view on time: that all the "moving" is an illusion (but not the geometrical temporal relationships themselves - which is what the dynamical laws in physics describe, of course).

Actually, personally, I'm quite fond of that view, because once you're there, it is not such a big step to accept that "observation" is also an illusion, facilitating an MWI view on quantum theory. That said, it is also good for one's mental health, to remember that all these ponderings are entirely hypothetical and only serve a purpose in helping to create mental pictures that make one understand the workings of a theory much better.

So it is probably also a healthy attitude to consider the opposite (and more intuitive) viewpoint too, which is that "time genuinly changes" ; just not to lock oneself up too much into one single paradigm.

 

[Ivan Seeking]

It doesn't say whether this observer is "travelling through" a geometrical time, or whether time is a dynamical phenomenon in itself.

It almost sounds like another twist on relativity.

ie. Is time moving past me or am I moving through it?

 

[kvantti]

Actually, personally, I'm quite fond of that view, because once you're there, it is not such a big step to accept that "observation" is also an illusion, facilitating an MWI view on quantum theory. That said, it is also good for one's mental health, to remember that all these ponderings are entirely hypothetical and only serve a purpose in helping to create mental pictures that make one understand the workings of a theory much better.

I also like the geometrical view of time and how it gets entangled with the MWI; they complete each other in quantum cosmology.

So it is probably also a healthy attitude to consider the opposite (and more intuitive) viewpoint too, which is that "time genuinly changes" ; just not to lock oneself up too much into one single paradigm.

Yeah everything is possible... altho I'm pretty sure, purely because of theoretical reasons, that the 4D MWI view of the universe is somewhat "true"... but that's just me. Until I find some reason to abandon it, I think I'll stick to it.

 

[vanesch]

ie. Is time moving past me or am I moving through it?

That's the most succinct expression of the problem I've ever seen :!)

 

[Paul Martin]

That's the most succinct expression of the problem I've ever seen :!)

I agree. I also think it is a good starting point for analyzing time. The next step, it seems to me, is to clearly identify what we mean by the terms 'me' and 'I' as they appear in the question. What exactly is it that might be moving through time, or that time might be moving past? I think the identification of that "thing" will not only elucidate time, but also the rest of existence as well.

Warm regards,

Paul

 

[AnssiH]

I agree. I also think it is a good starting point for analyzing time. The next step, it seems to me, is to clearly identify what we mean by the terms 'me' and 'I' as they appear in the question. What exactly is it that might be moving through time, or that time might be moving past? I think the identification of that "thing" will not only elucidate time, but also the rest of existence as well.

Try;


It is probably quite important to get rid of ideas about self as some kind of "object", and rather define subjective experience in terms of a process of some sort.

When you get to the ideas about time though, I would advice to open the door to the idea that motion is of metaphysical existence more than time. Well, I guess I've said that many times enough.

About whether it is "really" time or "consciousness" that is in motion, consider in what sense we could say anything to be in motion "in reality" in so far that we assume spacetime to exist.

Also remember that spacetime already defines completely how any natural object measures time, and any "speed" you imagine to this "motion of time" cannot be observed in any way. To think that the speed with which we consciously observe reality has something to do with the speed of flow of time or whatever is leaning to much towards naive realism for my liking. :P

-Anssi

 

[vanesch]

About whether it is "really" time or "consciousness" that is in motion, consider in what sense we could say anything to be in motion "in reality" in so far that we assume spacetime to exist.

Well, then you have already conceded to the geometrical view on time (the block universe view), and hence the question is then moot.

Also remember that spacetime already defines completely how any natural object measures time, and any "speed" you imagine to this "motion of time" cannot be observed in any way.

It's always the same thing. Everybody agrees that the physical parameter "time" (the "t" in the equations) is sufficient to explain all the "correlations" related to this parameter, and hence to "time": like the number of swings of a pendulum related to the position of the planet Mars or things like that.
What we are talking about here is that, to our subjective experience, there seems to be "only one value of t at a time" ; in other words, we don't experience "all the values of time simultaneously", while this is nevertheless what happens to other coordinates, such as x or y or z. We don't seem to experience "one x value at a time". But we do experience "one t value at a time". If t is geometrical, just as x or y, then there's no a priori reason for that. So then it must reside in whatever it is that suffers subjective experiences, that it takes "time in slices". Or it might be that time is ontologically a different thing than space after all, and that it "only comes in slices". Committing to a spacetime ontology already goes for the geometrical view on time, and hence leaves it entirely to the "nature of subjective experience" to see time come in slices, one at a time.

To think that the speed with which we consciously observe reality has something to do with the speed of flow of time or whatever is leaning to much towards naive realism for my liking. :P

I tend to agree with you, but we've been putting a lot onto the shoulders of "subjective experience" - one should be careful with that too, and not shove every single difficulty into that bin: the experience of time in spacetime physics, the experience of observation in MWI-QM, soon the experience of space with the holographic principle... We'll end up finding out that we're just a single character in a cosmic video game :-)

 

[AnssiH]

Well, then you have already conceded to the geometrical view on time (the block universe view), and hence the question is then moot.

You mean moot in that nothing can be said to be in motion once it has been claimed that spacetime exists?

I would tend to agree with this, but the point I was trying to make was that there exists motion in some sense in reality because we experience motion or change in our subjective experience, and our subjective experience is certainly caused by something in reality. It cannot be said that conscious experience could have any change in it without change existing in one sense or another.

So then it must reside in whatever it is that suffers subjective experiences, that it takes "time in slices". Or it might be that time is ontologically a different thing than space after all, and that it "only comes in slices".

Well, I would say that just the fact that we experience time so differently from space is already enough reason to say it is ontologically different. Also we should ask if it is fair to say that time or motion advances in discreet steps, or is it more proper to say it is continuous.

Committing to a spacetime ontology already goes for the geometrical view on time, and hence leaves it entirely to the "nature of subjective experience" to see time come in slices, one at a time.

Yeah exactly. Problems arise when you try and describe the nature of subjective experience. Without getting to the philosophy of the mind one could claim that everything is static in reality, and then hope that it could just be a subjective illusion that there appears to exist motion. It will become quite difficult to explain how could any illusion of motion exist when you have earlier denied any notion of metaphysical motion from reality...

I tend to agree with you, but we've been putting a lot onto the shoulders of "subjective experience" - one should be careful with that too, and not shove every single difficulty into that bin: the experience of time in spacetime physics, the experience of observation in MWI-QM, soon the experience of space with the holographic principle... We'll end up finding out that we're just a single character in a cosmic video game :-)

Well, I think we can say quite fairly that the static spacetime ontology can be used as a tool to "understand" reality, but it cannot be said that it actually is "like" reality. Map is not the territory here either.

-Anssi

 

[Paul Martin]

Well, I think we can say quite fairly that the static spacetime ontology can be used as a tool to "understand" reality, but it cannot be said that it actually is "like" reality. Map is not the territory here either.

Agreed. Let's start with that.

Let's suppose a 4D static spacetime ontology. Since the temporal dimension is static, it is similar to the spatial dimensions in some respects. The constraint it imposes, it seems to me, is that worldlines must have always increasing components in that dimension. (This may account for the asymmetry of that component in the spacetime metric, but I'll defer to someone else on that.)

In this analysis, the static spacetime is like the "map" you referred to. The "territory" then would be reality, which is what we would like to understand.

Problems arise when you try and describe the nature of subjective experience.

Maybe so, but let me give it a shot anyway. Then you can tell me where the problems are.

Without getting to the philosophy of the mind one could claim that everything is static in reality,

I think that claim would be going too far. Spacetime (the map) may be static, while reality (the territory) may include dynamic components above and beyond spacetime.

and then hope that it could just be a subjective illusion that there appears to exist motion.

I think that introducing the concepts of "hope", "subjective", "illusion", and "appears" cloud the question with unnecessary complexity.

It will become quite difficult to explain how could any illusion of motion exist when you have earlier denied any notion of metaphysical motion from reality...

Yes, that would be difficult. But we have not "denied any notion of metaphysical motion from reality" here. We have denied motion to spacetime (the map) but not to reality (the territory). Here's how I think it could be explained.

Spacetime is a finite static 4D structure with worldlines always increasing in one of the dimensions (the temporal one). That 4D structure is a manifold in a 6D structure. One of the additional dimensions is spatial and can participate in the same Euclidean metric as the three spatial dimensions of the 4D spacetime. This additional dimension allows more than adequate space for hypercomplex structures to exist for which the 4D spacetime bears the same relationship to them as Vanesch's video game does to us humans.

The second additional dimension is a temporal one in the same sense we consider our familiar temporal dimension allows for motion. Thus, structures in the 6D spacetime can move (possibly limited by the same sort of always increasing of time we sense).

If we identify some 5D structure in the 6D spacetime with the label "observer", then in this picture, the observer could "travel", or "proceed" along a worldline in the 4D spacetime, and to the observer, the illusion of motion in 4D spacetime would be evident, even though the 4D spacetime is really static.

At branch points in a worldline when the outcome of a particular quantum event might determine which branch to take, the observer would have a choice and could take either branch, or, in successive trips could take both paths.

Since the 4D spacetime manifold is finite, all worldlines have an end. Nothing would prevent the observer from constructing extensions to the manifold to lengthen particular world lines. This would mean that the 4D manifold (our observable universe) could evolve in its temporal dimension as it seems to have done.

It seems to me that this model not only would explain the illusion of motion in the static universe, but it could provide a framework for explaining a lot of other mysteries as well.

What problems do you see with it?

Warm regards,

Paul

 

[Andre]

Ever asked Augustinus what time is?

Confessiones XI, 14 "Quid est ergo tempus? si nemo ex me quaerat, scio; si quaerenti explicare velim, nescio."

What then is time? When nobody ask me I do know, when I want to explain somebody who asks it, I don't know.

 

[vanesch]

I would tend to agree with this, but the point I was trying to make was that there exists motion in some sense in reality because we experience motion or change in our subjective experience, and our subjective experience is certainly caused by something in reality.

That's then the extra hypothesis. I wouldn't go that far (I'm therefor a dualist). Of course, subjective reality is related to something in reality (that's the psycho-physical hypothesis), but in order to be able to say that "reality is static" (time is geometric), and nevertheless, we subjectively experience time as a motion (or a slice, or... well, something dynamical), I don't see how you can get away with having "subjective experience" entirely explained by the physical reality in which there's nothing else but time as a geometrical concept. In other words, you need somehow to "plug in something extra", outside of the spacetime reality itself, that can, in conjunction with the spacetime reality itself, make the subjective experience emerge. The fact that something extra is postulated, makes it a dualist view.

It cannot be said that conscious experience could have any change in it without change existing in one sense or another.

Exactly. And given that nothing is "changing" in a geometrical time view, the "ticking clock" must hence be "outside", and moreover individually linked to the "thing generating the subjective experience", which can then "plug it into the block universe" to extract the eigentime slice to be experienced. This wasn't a problem in a Newtonian view, where there was an ontologically "clicking clock" on which we could tap to do so.

As a sidenote, if I have the (dualistic) liberty to have an "outside of physical reality" ticking time clock, I can add to that an "outside of physical reality" random number generator to do the drawing in an MWI setting... that's why I try to argue that the philosophical problem with geometrical time is related to the philosophical problem of a multiverse - often without much success

Well, I would say that just the fact that we experience time so differently from space is already enough reason to say it is ontologically different.

The entire idea of a geometrical spacetime is to say that it is *not* fundamentally different.

Also we should ask if it is fair to say that time or motion advances in discreet steps, or is it more proper to say it is continuous.

Well, I think that this is difficult to distinguish: any continuous model can be arbitrarily well approximated by a discrete model with fine enough steps, no ?

Yeah exactly. Problems arise when you try and describe the nature of subjective experience. Without getting to the philosophy of the mind one could claim that everything is static in reality, and then hope that it could just be a subjective illusion that there appears to exist motion. It will become quite difficult to explain how could any illusion of motion exist when you have earlier denied any notion of metaphysical motion from reality...

... unless you accept a dualist vision. It is only in a strictly materialist view that this geometrical time poses a problem.

Well, I think we can say quite fairly that the static spacetime ontology can be used as a tool to "understand" reality, but it cannot be said that it actually is "like" reality. Map is not the territory here either.

Amen to that.
Ontological hypotheses (unverifiable as they are) must serve a purpose, and the purpose is to help us "understand" reality ; or better, the model we have of reality - which is nothing else but the physical theory under consideration.

 

[vanesch]

Spacetime is a finite static 4D structure with worldlines always increasing in one of the dimensions (the temporal one).

Hehe, and they decrease in the other direction

This is like the silly joke:
"how do you know whether a slope is rising or descending ?"
"easy, put a ball on it: if the ball rises, it is a rising slope, if it descends, it is a descending slope"

The second additional dimension is a temporal one in the same sense we consider our familiar temporal dimension allows for motion. Thus, structures in the 6D spacetime can move (possibly limited by the same sort of always increasing of time we sense).

Well, then, or it is not genuinly a geometrical dimension, or we're back to case one, where this dimension is again static.

If we identify some 5D structure in the 6D spacetime with the label "observer", then in this picture, the observer could "travel", or "proceed" along a worldline in the 4D spacetime, and to the observer, the illusion of motion in 4D spacetime would be evident, even though the 4D spacetime is really static.

What you now simply constructed is some new, 5-dimensional geometrical construction, and nothing is flowing in there either. IF you now put a universal "tag" on the 5-th dimension (a "running pointer" as in Newton's universal time), which, I take it, would "tick away eigentime" then you run into problems with your 4-d spacetime, unless you identified specific eigentime-worldlines for each individual "conscious being".

But that's nothing else but the "dualist subjective clock" I introduce...

At branch points in a worldline when the outcome of a particular quantum event might determine which branch to take, the observer would have a choice and could take either branch, or, in successive trips could take both paths.

Yup. Why not ? Nevertheless, you agree with me that this is happening "Outside of geometrical spacetime". Your "fifth dimension with a pointer" is then my "subjective clock", and the choices come down to my "subjective random generator".

You can of course "physicalise" dualistic notions, (you do this by introducing a 5th dimension + pointer and so on), but the point is, you need to introduce something dynamical and a whole lot of extra structure if there is only a geometrical notion of time (in 4-d spacetime), purely to explain the subjective notion of time slice.

In other words, with a purely geometrical view on time alone, it will be difficult to explain our subjective experience of time, although all physical observations are explainable that way. It is our subjective experience of time flow, and only that, which makes you consider this "extra structure".
The "extra structure" (without going into detail), needed only to explain an aspect of subjective experience, is what I call, a dualist notion (which I adhere to).

 

[AnssiH]

Spacetime (the map) may be static, while reality (the territory) may include dynamic components above and beyond spacetime.

Yeah, it is conceivable that there exist motion "outside" the 4D-block, but going along this route tends to make the ontology rather muddy instead of elegant.

Basically you can add more dimensions to express motion "to" spacetime, like you suggested, but then these dimensions too are static constructions, like Vanesch noted. The "2nd" temporal dimension cannot say "when" the changes happen to the 4D-spacetime (such as "a change" to a particular worldline), unless this 2nd dimension is actually in motion.

Then you have to include yet another dimension to express this motion. It is clear this leads to infinite regress.

(As a related note, ever noticed how people tend to assume there can exist motion to spacetime without ever suggesting any ontology to understand "when" these changes happen. For example in the description of transactional interpretation of QM, where information "first" flows forward in time and "then" comes backwards in time, or about how measuring something in QM causes changes "elsewhere" in spacetime "simultaneously". How does something "change" in spacetime here? More clarity is needed to the terminology that people use here)

Another option is, like Vanesch suggests, to consider some flavour of dualism. I.e. to consider that in some sense, conscious experience or "consciousness" is some kind of "thing" that is "really" in motion in relation to the temporal dimension. I.e. that there exists a metaphysical "pointer" that is "reading" the time-dimension.

This at least does not lead to infinite regress, but it does lean towards naive realism. Not all facets of our semantical notion of "motion" are appropriate for the motion of this "pointer".

Let me explain. Naive realist view of time is that time objectively moves forward "at the speed" that we subjective perceive it to. But once you look into human perception processes, it stands to reason that the speed with which we perceive "motion" or "time" depends wholly on the speed with which the natural processes in the brain can recognize things. If you are looking at a spinning wheel, you have a subjective experience of its motion occurring at certain speed, from which you could derive some idea about the speed with which "time" is moving. But imagine how it would feel if all the natural recognition processes of the brain were to move twice as fast as usual suddenly. Would you not perceive the wheel to rotate at half the speed? Basically everything you'd perceive would move half the speed of usual, and it would feel as if time slowed down, even though you just "speeded up".

Notice now, that the natural recognition processes of the brain, and in particular the speed of their motion in relation to the "spinning wheel", are already completely defined in a static spacetime. In other words, the "speed" at which this metaphysical "pointer" moves does not change the "speed" of the subjective experience at all.

We should ask here, could even the direction of the motion of this pointer change the experience? Could we "remember the future"? Of course not, that is another assumption that could only be made in the naive realism framework.

So, the idea of "speed" to our idea of "motion" is nonsensical when we try to understand the motion of this metaphysical "pointer". It would only be the fact that the pointer can exist only in "one" location at one time that could give us any further clarity to subjective experience. It is up to debate whether this could be enough or not. And it definitely is up to debate whether this view of reality is elegant or not.

Also, I adviced before to keep the door open to the idea that it is motion after all that is of metaphysical existence. Just like one might thoughtlessly claim that "there can be no motion without time", another man can claim " without motion there could not be any notion of time". The point is that there are some things in reality that are fundamental, and there is no reason why motion could not be one of them, and thus time would be a semantical concept but nothing more.

It should be obvious that when we "measure time" in semantical sense, we are actually measuring how far a clock moves during the period that some other system moves from somewhere to another place. I.e. we cannot measure "time" directly, we can only compare motions.

The difficulty with this would be that it would be required for simultaneity to be absolute. It is worth noting here, that it would not mean that the math of relativity would be false; all the observable effect could still be the same. The ideas about time dilation would just turn into form of how and why physical processes proceed at different speeds in different environments. These sorts of models can be built, and many have been built, and the only thing they change is that time travel would be impossible; the past and the future would not exist "all the time". (Note that the idea of time travel is also an idea of "change" happening to spacetime "when the time travel happens", and if you insisit ontological clarity here, you would require the 2nd time dimension, and 3rd, and 4th...)

Well, I think that this is difficult to distinguish: any continuous model can be arbitrarily well approximated by a discrete model with fine enough steps, no ?

Yes, and actually there are models with discrete time steps that even have the power to explain some quantum behaviour. This question also remains whether one assumes it to be "time" or "motion" that is more fundamental. Motion too can happen in discrete steps.

 

[Philocrat]

I can no longer see time. All I recognize is the morphing and changing of energies/masses/matters. This concept of time we have is slowly deteriorating from my mind. There is no time, all things are just constantly changing? Nothing ever really leaves us... and nothing is ever really born new in terms of energy. So all that we have is all that we have and it never goes anywhere except for changing into differenent physical, dimensional, and material states? So everything is not really passing... only changing. Time will never leave us, we must learn to leave time.

Hello Outlandish, I totally understand your frustation over this very subject. At one point a few years back, I thought that I was the only one left alive on this planet who is deeply concerned with the sort of spooky tricks that the notion of time plays on the human imagination. Over the years I have thought long and hard about this subject, at least at the philosophical level of things, but each time I always came out empty-handed. The issues you are raising here about time are just a tiny bit of the grand scale of things. Now let me lend you a hand to expand on the overal scale of the problems that we are facing both scientifically and philosophically by looking at each each issue in turn:

There is no time, all things are just constantly changing?

Yes, so it appears to us in the outer. But this problem is two-fold (1) the Illusory nature of time and (2) the Illusory Nature of change itself. Time appears illusory because of the way science itself accounts for it by division into quantifiable dimensions, of which many people on this thread have already deduced the resulting implications. The other problem is the relationship between something and Nothing. Of this, I have already argued that there is no such relation since it is naturally impossible for something to come from nothing, let alone decline back into nothing. If time is something, then it is impossible for it to be nothing, hence it must exist in some physically accountable form. But is this really the case? Is time something?

So all that we have is all that we have and it never goes anywhere except for changing into differenent physical, dimensional, and material states? So everything is not really passing... only changing[.

Well, this is metaphysically equivalent to denying some dimensions of time itself. When things change time ought to elapse! So, presumably there are quantifiable elapsed times between changing things and events. Metaphysically, as we say in philosophy, the spatio-temporal histories of those changing things and events are inevitably created. It is when we analyse such spatio-temporal histories that the notion of time dimensions (past, present and future) begin to confront us both in our observation and in the actual analysis. If this is the case, your text does appear as if though you are suggesting that such histories are infected or polluted by sudden disappearance of all the time dimensions that may be found in them during the observation or analysis of them. Is this what your text is implying? Is this what makes you declare time as a whole delusory?

A more radical observation in recent times is the sudden appearance of time in the spectrum of reality as if though there is no present in anyone spatio-temporal history of a given event. Some people are already suggesting that this is the case, that we are always either in the past or in the future. This is a different angle of the problem which, as in your own text, makes the notion of time equally delusive. I am not quite sure if this is the case as I have written something on this forum that denies this possibility, which however also ended in declaring time equally delusive but in a completely different light. What I wrote about time was blacklisted on this forum because it was not a standard science and made what may be construed as wild claims. One of the questions I asked in that posting is whether zero-history events, actions or changes are possible? Can events occur at time t=0 regardless of the physical distances between them in spacetime?
Events that leave no histories behind, sptiotemporally, is metaphysically spooky and how we even begin to think about them is equally spooky.

My argument therefore is that if zero-history events exist, then it is under this metaphysical condition that time can be construed as being illusory. Metaphysically, this would be equivalent to being physically and psychologically devoid of time in the strictest sense of the word.