Time will tell. :smile:
Under the influence of cannabis I wrote a long explanation where I argued that everything was Time and Timespeed.

Weed and philosophy go together like oreos and milk or in case you are english, like biscuits and tea. :wink:

Absolutely. Without the stuff I would be practically brain-dead. My best ideas are THC inspired.

If everything in the universe stopped moving in an absolute sense. Will time still exist or is it independent of any such circumstances ? — Wittgenstein

How could there be time without change? Time is a measure of change, or more precisely a measure of relative change (a comparison of some change relative to some other change, or said differently a comparison of some process relative to some other process).

Can a philosophical approach really tackle this question as the physicist have more concrete ways of dealing with it. Is it up to them to resolve this debate ? — Wittgenstein

It would be a fallacy to think that physicists can tackle this question more profoundly, they cannot escape the above philosophical observation. Physics describes change, relates some change to some other change, even if physics could describe perfectly how things move (how change evolves) it still wouldn’t explain why things move in the first place (why there is change at all).

Either change always existed, or change arose from the absence of change, but the transition from non-change to change cannot be described in term of a process, it cannot be explained, so physics will never explain that.

Either change always existed or change arose from non-change at some point in the past, but is it even meaningful to make a distinction between the two options? For instance if we say that “change arose from non-change X years ago”, we say that if the Earth and the Sun had existed since the very beginning then the Earth would have revolved X times around the Sun since then, but presumably the Earth and the Sun didn’t exist back then and we don’t know what processes were taking places at the very beginning. If at the very beginning there was change that we cannot compare to any change that we have now (even if we use atomic processes as a clock instead of the Earth and the Sun), then we cannot meaningfully say how long ago was the beginning, how far back in the past change began is indeterminate, so in this sense it is not meaningful to ask whether there was always change or whether change arose from non-change.

From our vantage point what we can say is that change exists, and the absence of change that we see is always described relative to some change, for instance if we look at a blank wall while staying perfectly still and not moving the eyes, there is still change going on such as our thoughts, our heartbeat, our breathing or our imagination.

To sum up change exists, time is a relative measure of change, when change began is indeterminate, and there is no existence without change (existence can be defined as change itself).

Time isn't a property, it is a concept. Even in absence of changes to observe, a mind that is observing will still conceive of the concept.

Time is a perception of a rate of change, most ultimately the lifespan. It is a concept useful to humans who organise, to manage their actions and ensure that they remain in control of circumstances when a future (anticipated) situation arrives. For that reason, the sun has traditionally been useful as a dictation of regular patterns of light and darkness, hot and cold.

I don't know if there are any creatures who don't perceive of time, even if they don't think much of it. Babies don't seem to think much about time, that's for sure, because they have not learned the rhythms and patterns of life. They wake and sleep whenever, they don't dwell on past trauma and they don't plan on pooping as soon as they leave the house. Does that mean time does not exist in their world? .. of course it doesn't, because time exists merely as a result of someone conceiving of it, and that comes naturally as we grow to recognise patterns of need and provision. Also, animals can quickly learn to anticipate regular feeding times (birds can identify such patterns after only two events!).

Because it is a concept, it isn't a thing that exists by itself as a rock does. Time only exists as a result of someone having conceived of it. Change happens regardless of someone measuring the rate of change as time.

First things first.

"If everything in the universe stopped moving in an absolute sense..."

Point: "Since motion in the universe can only be defined in relation to arbitrary reference points, per Relativity Theory, it is not possible to stop moving in an 'absolute' sense".

Counter-point: "But if every reference point appeared to be motionless in relation to every other reference point, that would effectively be cessation of motion in an 'absolute' sense."

Point: "Not necessarily. Every reference point could be apparently motionless in relation to every other, but the universe as a whole might be rotating. Alternatively, the apparent motionlessness might be only a special case of relative motion, just as the number 0 is a special case of 'number', in that it has no positive or negative value."

Counterpoint: "But how would we know that the universe is rotating? After all, the universe is by definition 'everything'. By what reference point could it possibly be rotating?"

Point: "Our definition of 'universe' is itself framed within the limitations of our own understanding. The fact is, we simply have no firm conception whether there might be anything 'outside' of the known universe, in either space or time. The question whether it might be rotating in respect of some unknown (and perhaps, to us, inconceivable) reference point therefore remains open."

Counterpoint: "And as to the apparent absolute motionlessness being merely a special case of 'motion', how could we possibly establish that?"

Point: "We can't. But as a matter of scientific logic, in the absence of any internal logical contradiction, the hypothesis cannot be excluded."

Counterpoint: "So the question whether everything in the universe could stop moving in an absolute sense is unanswerable?"

Point: "I'm afraid so."

How could there be time without change? Time is a measure of change, or more precisely a measure of relative change (a comparison of some change relative to some other change, or said differently a comparison of some process relative to some other process).

It's easy to see the existence of time without a sense to detect change. Change in of itself is meaningless as it has to be detected by someone.Consider yourself in a system where every object is moving with the same velocity. In that case, you won't be able to see change but motion presupposes time according to you, hence you would still require time.

Either change always existed, or change arose from the absence of change, but the transition from non-change to change cannot be described in term of a process, it cannot be explained, so physics will never explain that.

In that case, we run into a paradox. Let's suppose change emerged from non change hence time was invented after change existed,but since the transition itself requires time, we have to assume time existed before change existed in order for non change to turn into change.
If we suppose non change was always there we run into an infinite regress. You see the problem with both solutions.

It's easy to see the existence of time without a sense to detect change. Change in of itself is meaningless as it has to be detected by someone. — Wittgenstein

Wouldn't that mean a past before an observer does not exits? The Big Bang only exists (as a past event) because we are able to look into the past?

That's a nice way of describing the progression of the argument.

Our definition of 'universe' is itself framed within the limitations of our own understanding. The fact is, we simply have no firm conception whether there might be anything 'outside' of the known universe, in either space or time. The question whether it might be rotating in respect of some unknown (and perhaps, to us, inconceivable) reference point therefore remains open."

Let's suppose God could see a static universe with nothing around it in that dimension as a thought experiment. Would the universe cease to have time then ?

In a way, yes. Since the past is captured by objects that existed before the present like the light from the stars that have died and don't exist anymore.The past is essentially information otherwise if we suppose it exists like the present, then the present would be the past, that wouldn't make sense in a way.

Change in of itself is meaningless as it has to be detected by someone. — Wittgenstein

Do you believe anything exists without a (sub)conscious observer?
Does time, space and matter a priori require the existence of life?

Its a classical question and l want to know why you support one viewpoint or another. Maybe there is a third alternative, such as rejecting the question as being wrong.

If everything in the universe stopped moving in an absolute sense. Will time still exist or is it independent of any such circumstances ?

Now the next step in answering this question seems to be. What do you mean by exist when referring to time ?
In my opinion, this question is identical to the earlier question and doesn't really resolve anything.

Can a philosophical approach really tackle this question as the physicist have more concrete ways of dealing with it. Is it up to them to resolve this debate ? — Wittgenstein

To the extent that I can tell, time combines with space to provide a universal frame of reference, space-time, for everything in the universe. To use a theatrical analogy it provides a stage where every event and object in our universe must occur and exist respectively.

It seems space has been defined as a boundless 3 dimensional extent.

The definition of time in Wikipedia suggests a progression of existence from the past, through the present, and into the future.

The Einsteinian concept of time as a fourth dimension added onto the 3 dimensions of space to create space-time makes complete sense when we think of it in terms of information. How much information is sufficient to pinpoint the location of an object/event in our world? We need 3 spatial coordinates and 1 time coordinate. Why not just consider time a fourth dimension then?

One thing that might give us insight into the nature of time is how the arrow of time is explained in terms of increasing entropy. The relevant bit here being the difference, the lack of resemblance due to entropy between the past and the present and the present and the future. This suggests that without change there would be no direction to time. The big question then is is change just a direction indicator for time or is change time itself?

Let's consider the scenario you presented, a world without motion, as a standin for the real scenario we need to consider - a world without change. In such a world there won't be a direction to time, nor will there be a way to measure time. However, this doesn't mean there is no time for the simple reason that even in the world we're familiar with there are things that don't change e.g. physical constants or mathematical truths etc. but that doesn't imply that there is no time, does it? Ergo, even if time is measurable and has direction only because of change, time isn't change and doesn't draw the essence of its existence from change.

What is time then?

Let's assume for the moment that time isn't real and therefore all is space, space being something we're more familiar with. Such a viewpoint initially makes sense after all if you look at an analog watch time is marked off at regular distances (space) and time seems to be just the distance the hands of a watch travels. However this illusion doesn't last long since we still need to have the hands moving at a particular speed or rate for it to give time accurately and this requires time to be something independent of space.

It's easy to see the existence of time without a sense to detect change. Change in of itself is meaningless as it has to be detected by someone. — Wittgenstein

If you couldn’t detect change you wouldn’t come up with the concept of time. There might be change without a sense to detect change but there cannot be time without a sense to detect change.

Consider yourself in a system where every object is moving with the same velocity. In that case, you won't be able to see change but motion presupposes time according to you, hence you would still require time. — Wittgenstein

If I am in a system in which every object is at rest, why would I say they are moving at a constant velocity? They have no velocity. Also I never said that “motion presupposes time”, what I say is that time is a measure of change, and motion is a form of change. Change precedes the concept of time, not the other way around.

Also if I am in a system in which all objects besides me are at rest, I would still see change: if I move my eyes the scenery would change, I would sense my heartbeat, my thoughts and imagination could change, ...

Also, velocity doesn’t have to be defined as distance over time, it can be defined as a fundamental concept without reference to time, I recall that Max Jammer did that in one of his books, so any argument invoking velocity cannot prove that time precedes motion.

In that case, we run into a paradox. Let's suppose change emerged from non change hence time was invented after change existed,but since the transition itself requires time, we have to assume time existed before change existed in order for non change to turn into change.
If we suppose non change was always there we run into an infinite regress. You see the problem with both solutions. — Wittgenstein

As I said the ‘transition’ wouldn’t be a process, suddenly there would be change, but no one would be there to see it so it’s not even meaningful to speak of it that way. Change already exists as soon as the transition begins, so the ‘transition’ itself belongs to change, there is no change (and thus no time) before change. And again no one would be there to see it, if you assume someone is looking at non-change turning into change then that means there was already a being so there was already change.

If instead we suppose that change was always there, there is no beginning, so fundamentally there is no infinite regress, you would never find a beginning because there simply isn’t one. If you can’t find something that doesn’t exist then just stop looking for it.

And as I explained, “when change began” is undefined so it’s not useful to talk about it in those terms anyway. What we can say is that there is change now, even our memories of the past are experienced now, in the present. There is change and time is a relative measure of change, that’s all there is to it.

Interesting point, with many ramifications. I need some time to think it through.

Your summary of the contemporary viewpoint of time in science is quite impressive and accurate as far as my knowledge is concerned.
To get to your big question which is really interesting.

This suggests that without change there would be no direction to time. The big question then is is change just a direction indicator for time or is change time itself?

Let's consider the scenario you presented, a world without motion, as a standin for the real scenario we need to consider - a world without change. In such a world there won't be a direction to time, nor will there be a way to measure time. However, this doesn't mean there is no time for the simple reason that even in the world we're familiar with there are things that don't change e.g. physical constants or mathematical truths etc. but that doesn't imply that there is no time, does it? Ergo, even if time is measurable and has direction only because of change, time isn't change and doesn't draw the essence of its existence from change.

Since time provides us some key information about an object besides the 3 dimensional coordinates. In that way change provides us information of the type of change along with the length of change and so on. However, you can judge for yourself that change provides way more information about an object in the universe than time itself. Hence time cannot be change in my opinion. However, time can be an essential component of change (or not) and that is the crucial aspect of the relation between these two concepts. This question still remains unaddressed.

We agree with the conclusion that time isn't change but l don't think your argument for the independence of time from change holds weight. The universal constants and mathematical truths do not exit in spacetime as material objects and hence they would not count as an example to prove independence of time. Besides that, even if we suppose that there are objects that do not change, then it would not be possible to let other things around them change as time either applies to all objects in a system or it doesn't.

There might be change without a sense to detect change but there cannot be time without a sense to detect change.

So in a universe with time, all changes would be detectable. Hence time puts a constraint on change, all changes now depends on time. But you mention further ahead.

. Change precedes the concept of time, not the other way around.

Maybe it's just me but if change precedes time, are you implying that change comes first and then we get time. If that's not what you meant, can you clarify this point.We usually talk about change and time simultaneously and how can change which precedes time, be dependent on time which follows from it.

If I am in a system in which every object is at rest, why would I say they are moving at a constant velocity? They have no velocity. Also I never said that “motion presupposes time”, what I say is that time is a measure of change, and motion is a form of change. Change precedes the concept of time, not the other way around.

Also if I am in a system in which all objects besides me are at rest, I would still see change: if I move my eyes the scenery would change, I would sense my heartbeat, my thoughts and imagination could change, ...

A system in which all bodies are at rest is identical to a body in which all bodies are moving at a constant velocity as in both systems, change is not detectable. I think change includes time as a measure and it would be incorrect to say that time is a measure of motion as motion includes distance too. The units are totally different. Time is a measure of time and motion is a measure of distance or displacement/time. You cannot place yourself outside the framework of time and place all other objects under time in the same system. At most you can select a different framework with respect to time.Time either applies to everything or it doesn't in a system.

Also, velocity doesn’t have to be defined as distance over time, it can be defined as a fundamental concept

I haven't come across any such definition and could you define it here. That would either reduce velocity to something else or compromise all other physical units that depend on it.

As I said the ‘transition’ wouldn’t be a process, suddenly there would be change, but no one would be there to see it so it’s not even meaningful to speak of it that way. Change already exists as soon as the transition begins, so the ‘transition’ itself belongs to change, there is no change (and thus no time) before change. And again no one would be there to see it, if you assume someone is looking at non-change turning into change then that means there was already a being so there was already change.

If we take this viewpoint into consideration, the interval between change and non-change would not even be zero as you noted that the transition also belongs to change. The state of non-change and change overlap and from non-change emerged change. Would this imply that the state of change is the same as the state of non change as they could be replaced by each other. Won't that be a contradiction.

If instead we suppose that change was always there, there is no beginning, so fundamentally there is no infinite regress, you would never find a beginning because there simply isn’t one. If you can’t find something that doesn’t exist then just stop looking for it.

This would mean that some objects were being changed forever. Let's apply this supposition to an example, suppose that an object is accelerating in this system and if we also assume it was accelerating whenever we look back into the past, it would have an infinite velocity at present, which wouldn't make sense in a physical world. That's just my little thought experiment.

Time, Change and Space

I do not think one can separate these concepts in any meaningful way. In modern physics space is not a fixed, empty, void. Space is QFT and there are constant random fluctuations in the energy value of any location in the field, with virtual particles appearing and disappearing (the Dirac Sea). Thus change (and its abstraction time) is built into the very structure of space. The universe is not, never was, cannot be, a static being. The universe is a continuous becoming and thus change (time) is built into the very structure of the world.

I think the modern QFT does not use dirac sea as positrons are good for describing why the universe does not show an excess of negative charge. Besides that, how can you suppose the universe existed forever and let's suppose it didn't exist forever, how would you explain the transformation from non time to time.

I think the modern QFT does not use dirac sea as positrons are good for describing why the universe does not show an excess of negative charge. Besides that, how can you suppose the universe existed forever and let's suppose it didn't exist forever, how would you explain the transformation from non time to time.

That's generally a difficult question to answer but with respect to the past, an observer is required. As far as the present world is concerned, we can possibly think of the independence of the physical world from our senses.
In a technical sense, if we want non-materialistic objects
(mathematical truths) to have a world of their own, we will need an observer in that sense but as far as material objects are required, generally no. But for theist like me,everything that exists has atleast 1 observer.

Assertions of change are relative to a notion of identity, which is terminological.

For example, suppose that every waking moment is labelled by the current reading of an atomic clock, such that no two situations are considered to be identical. Relative to such nominalistic terminology, there isn't a notion of identity, and hence there is neither a notion of change nor permanence.

Hence time cannot be change in my opinion. However, time can be an essential component of change (or not) and that is the crucial aspect of the relation between these two concepts. This question still remains unaddressed.

We agree with the conclusion that time isn't change but l don't think your argument for the independence of time from change holds weight. — Wittgenstein

I'll take another shot at it. This time I'll use change.

Imagine a person walking and an ice cube stationary in a cup. The person walking changes position because there's a difference in her relative position with other objects.

The ice cube on the other hand also changes - it melts into a puddle of water in the cup - but the change hasn't occurred in space for it was stationary. Yet we can frame the history if the ice cube as it was like this before, it is like this now and then became like this after. This non-spatial domain where change can be sequenced as before, now, and after is time.

Maybe it's just me but if change precedes time, are you implying that change comes first and then we get time. If that's not what you meant, can you clarify this point.We usually talk about change and time simultaneously and how can change which precedes time, be dependent on time which follows from it. — Wittgenstein

Because change happens regardless of what we think about it, whereas time is a concept we create. Within change (existence) we observe periodic change, such as day-night-day-night-day-..., or winter-spring-summer-autumn-winter-..., from these periodic changes we come up with the concept of clock and of time, but that concept is a creation, at no point have we observed some entity called ‘time’ that is passing or flowing.

I mentioned that if we couldn’t see change we wouldn’t come up with the concept of time, but going further than that if we only saw disordered change and couldn’t see any periodic change, I would say we wouldn’t come up with the concept of time either, the past would blend with the future there wouldn’t be a noticeable difference between them (for instance imagine if all we saw was white noise).

A system in which all bodies are at rest is identical to a body in which all bodies are moving at a constant velocity as in both systems, change is not detectable. — Wittgenstein

But velocity relative to what? If you detect that your system is moving at a constant velocity relative to something else, then you do detect change. Also in practice the two systems you mention are not identical, the principle of relativity is an idealized principle, in practice for instance with the proper instruments you do detect your motion relative to the cosmic microwave background which is everywhere (the two systems you mention wouldn’t see that background at the same frequency).

I haven't come across any such definition and could you define it here. That would either reduce velocity to something else or compromise all other physical units that depend on it. — Wittgenstein

Velocity could be seen as a fundamental quantity that is measured with a speedometer. Then you can pick distance as another fundamental quantity (measured with rulers) and then time becomes a derived quantity.

Of course the reading of the speedometer must not be calculated from distance and time otherwise it wouldn’t be fundamental. But basically when we observe motion we have a sense of how fast something is going, we don’t have to use rulers and clocks in order to determine whether something is going fast or slow in our visual field, we can describe motion and more generally change without seeing time as fundamental.

Again the simplest way to see it all is to say that change occurs, and that distance, time, velocity, ... are tools we created to describe that change, to relate some part of that change to some other part of it. Thinking of distance and time as existing prior to or independently of change leads to never-ending confusion, they are tools we created they aren’t things existing independently of everything we observe.

If we take this viewpoint into consideration, the interval between change and non-change would not even be zero as you noted that the transition also belongs to change. The state of non-change and change overlap and from non-change emerged change. Would this imply that the state of change is the same as the state of non change as they could be replaced by each other. Won't that be a contradiction. — Wittgenstein

Well there would be nothing before change, nothing to observe non-change turning into change, so strictly speaking the state of non-change doesn’t exist, there is nothing that turns into change, it’s simply that change occurs, we can’t say what happened before because nothing happened, nothing existed so there is no overlap.

If we try to imagine the state of non-change we’re doing it wrong, usually we imagine ourselves as observing an absence of change but that’s not what non-change is because we are beings who change, we have thoughts, we have a heartbeat, so non-change is not an observation of non-change, it is the absence of existence, we can’t picture it because by trying to picture it we’re including existence in the picture.

A movie has a beginning because it fits within something greater (our life), but the whole of existence does not fit into anything greater so it doesn’t have a beginning we can conceptualize.

This would mean that some objects were being changed forever. Let's apply this supposition to an example, suppose that an object is accelerating in this system and if we also assume it was accelerating whenever we look back into the past, it would have an infinite velocity at present, which wouldn't make sense in a physical world. That's just my little thought experiment. — Wittgenstein

Why would we assume that it could accelerate forever in a single direction? A thing can’t accelerate on its own there is always something else accelerating it, either a gravitational body such as a planet (but then the thing stops accelerating when it crashes into the planet), or an electromagnetic interaction such as when rocket fuel explodes and the electrons of one part of the fuel push onto the rocket while the other part is ejected out of the rocket (but then the rocket stops accelerating when all the fuel has exploded). Or you can have endless acceleration in circular motion where the orbiting body doesn’t gain speed (planet around a star, electron around an atom) and where the acceleration prevents the body from going into a straight line.

Even assuming you could somehow accelerate something indefinitely, the longer you accelerate the less you gain speed as you approach the speed of light, you approach the speed of light asymptotically, that’s why the speed of light is seen as a speed limit. And if somehow it turns out that we can travel faster than light and that there is no speed limit, in order to accelerate the object indefinitely you would need an infinite amount of fuel in the first place, you would run out of fuel way before the thing reaches infinite velocity.