Time flies like an arrow. Fruit flies like a banana

[Sriram]

I don't think this captures Rose's point. My perception of the passage of time as measured by my wristwatch is the same as an astronaut's perception of the passage of time as measured by his wristwatch whilst on the ISS.  But they aren't the same.  If time does not exist how can it vary from place to place ?

My point is that only 'change' actually exists. Time is just our way of measuring change.

If there are any variations in Time from place to place it only means that 'Change' varies from place to place. 

[torridon]

My point is that only 'change' actually exists. Time is just our way of measuring change.

If there are any variations in Time from place to place it only means that 'Change' varies from place to place.

Isn't this just avoiding dealing with the underlying concept by means of a simple word switch - using 'change' instead of 'time' ? Why would rate of change be sensitive to gravity ?

[Shaker]

Isn't this just avoiding dealing with the underlying concept by means of a simple word switch - using 'change' instead of 'time' ?

No, since the principle at work here is that there are those who assert - and it is only an assertion - that time is fundamental and objectively 'out there' always and for ever true. Change is obvious; the perception-independent, objective background reality of time is a thing that needs to be argued for and evidenced.

Why would rate of change be sensitive to gravity ?

Why would 'time'?

In fact you're almost making Sriram's case for him, in a way. Gravity acts upon matter; the change that Sriram is referring to is an alteration in the configuration of matter, a difference in a particular state of affairs of the universe, and we deploy a useful but subjective tool called time in order to track such differences.

[torridon]

Presumably because the perception of time, rather than anything like objective, perception-independent time, is entirely subjective. You say that your perception of time and the astronaut's perception of time are the same, yet we know (and can measure) that they're different; but even aboard the ISS the difference is so minuscule that there's no perception of difference. After all, technically speaking there's a time difference (even smaller, in thus case) between the ground floor and the highest point of the Shard, or the Burj Khalifa for example.

It is not just the human perception of time, it is time measured by an insentient device and the differences between different measuring devices indicate that there is no such thing as a universal 'now'.  That rules out a Newtonian view of time; every measuring device has its own subjective view of things so give varying results but there must be a thing there in order for it to vary.

[Shaker]

It is not just the human perception of time, it is time measured by an insentient device and the differences between different measuring devices indicate that there is no such thing as a universal 'now'.

1. Though the devices may be insentient, they're humanly-created in order to measure this thing that humans call time; to regard this as evidence of objective, 'out there' time is a question-begging circular argument.

2. We may be at cross-purposes here - I'm not arguing for a universal Now in quite the way that you seem to think, if I understand you aright; that seems to imply that a universal Now is some definite and concrete 'thing' analogous to the Taj Mahal or Niagara Falls that everybody can visit and agree upon or fail to visit. Rather the point is that from the p.o.v. of subjective human experience, it not only always is but can only ever be Now. Eckhart Tolle poses the question: think of absolutely any moment at absolutely any point in your life doing absolutely anything (good, bad or neutral doesn't matter in this context) - was there ever any of those moments where your subjective perception was anywhere other than in the Now? The answer has to be no.

That rules out a Newtonian view of time; every measuring device has its own subjective view of things so give varying results but there must be a thing there in order for it to vary.

Not 100% sure I follow the train of thought here. If you're arguing for an objective, perception-independent reality of time, what does it say about its objectivity if it varies?

[Nearly Sane]

Surely Now is the same as self, it is precisely not the thing you can think about because it's reflexive. In trying to think about doing it you stop being able to do it.

[ekim]

Surely Now is the same as self, it is precisely not the thing you can think about because it's reflexive. In trying to think about doing it you stop being able to do it.

More or less.  Past, present and future are mental constructs.  You can think about them but then that is just another flow, in this case, of mental energy.

[Nearly Sane]

Are they mental constructs? That makes it sound a deliberate choice, and surely we don't have a choice in the way we experience things?

[ekim]

Are they mental constructs? That makes it sound a deliberate choice, and surely we don't have a choice in the way we experience things?

Sorry, I'm not sure I understand what you are asking, but as regards the idea being discussed about the existence of time, events just happen, change, interact.  The past is based upon memory or record of change, the future is based upon an assessment of probability of change and I suppose that the present is seen as a snapshot of immediate events.  As regards choice, I suppose that some would say that you can choose to reflect upon memories of the 'past' or imagine the probability/possibility of 'future' events and allow 'present' events to arise as they will and be viewed as they are.  There is no entity called 'time' involved, just change at different rates sometimes orderly, sometimes chaotically which the mind attempts to grapple with.

[Udayana]

...
I read Julian Barbour's (supposedly popular science but actually hard-going) The End of Time some years ago and was promptly won over to his thesis about the unreality of time - I've long threatened to bore everybody into the shagpile with a thread on it (though it's incredibly difficult to do in words alone, without pictures or diagrams) ... but so far Sriram has come close to expressing the central idea:

Unfortunately I found that book to be, basically, unreadable and it has been left in the pile for some future decade (if there can be such a thing).  Anyway, what are the implications of the non-existence of time? Does it mean that I don't have to follow speed limit restrictions? or that I can get to Mars without having to pack first?

[Udayana]

... There is no entity called 'time' involved, just change at different rates sometimes orderly, sometimes chaotically which the mind attempts to grapple with.

What do you meant by "rates" if there is no time?

[Nearly Sane]

Sorry, I'm not sure I understand what you are asking, but as regards the idea being discussed about the existence of time, events just happen, change, interact.  The past is based upon memory or record of change, the future is based upon an assessment of probability of change and I suppose that the present is seen as a snapshot of immediate events.  As regards choice, I suppose that some would say that you can choose to reflect upon memories of the 'past' or imagine the probability/possibility of 'future' events and allow 'present' events to arise as they will and be viewed as they are.  There is no entity called 'time' involved, just change at different rates sometimes orderly, sometimes chaotically which the mind attempts to grapple with.

I think that this is s strawman. I haven't seen anyone suggest there is an entity called time. And in exactly the same way, there isn't an entity space but time is simply a description of the dimension in which things change, just as space is the dimension in which they move.

The question is about whether time is purely a construct of the mind or is an inevitable way of experiencing.

[Udayana]

Agree, it's why so much use of quantum is a meaningless game. The difficulties of it are used to smuggle in any conclusion.

Yes, - for any claims to taken seriously a consistent model must be provided with experimental validation.

[torridon]

1. Though the devices may be insentient, they're humanly-created in order to measure this thing that humans call time; to regard this as evidence of objective, 'out there' time is a question-begging circular argument.

2. We may be at cross-purposes here - I'm not arguing for a universal Now in quite the way that you seem to think, if I understand you aright; that seems to imply that a universal Now is some definite and concrete 'thing' analogous to the Taj Mahal or Niagara Falls that everybody can visit and agree upon or fail to visit. Rather the point is that from the p.o.v. of subjective human experience, it not only always is but can only ever be Now. Eckhart Tolle poses the question: think of absolutely any moment at absolutely any point in your life doing absolutely anything (good, bad or neutral doesn't matter in this context) - was there ever any of those moments where your subjective perception was anywhere other than in the Now? The answer has to be no.
Not 100% sure I follow the train of thought here. If you're arguing for an objective, perception-independent reality of time, what does it say about its objectivity if it varies?

Whether clocks are manmade or not merely confuses the issue by introducing the messy business of human perception into it. At the heart of the clock there is an entirely natural regular energy state oscillation of a caesium 133 atom that we use to calibrate what we normally call time.  What is being calibrated there if not time, or time by some other name, like duration, or change.  Maybe it is not a question of reality but a question of usefulness of conceptualisation.  Maybe strings don't exist, but are a useful mathematical tool to conceptualise subatomic matter. Maybe we could say the same for time, it is a convenience for something we don't actually understand, but the fact of locality and variation in the beatings of said caesium atoms requires us to incorporate time as a dimension into conceptual models otherwise we sacrifice authenticity. 

Sorry, brain starting meltdown now, knew it was a mistake to get into this .... 

[torridon]

Surely Now is the same as self, it is precisely not the thing you can think about because it's reflexive. In trying to think about doing it you stop being able to do it.

Maybe that resonates with the Buddhist insight that the more you go looking for the self, the more it is not there. Also with the Xeno paradox of motion.  Exactly how long is now ? A valid concept of now requires it to be of zero duration, so 'now' cannot actually exist for the same reason that a string of zero length is not a string.

[Udayana]

Whether clocks are manmade or not merely confuses the issue by introducing the messy business of human perception into it. At the heart of the clock there is an entirely natural regular energy state oscillation of a caesium 133 atom that we use to calibrate what we normally call time.  What is being calibrated there if not time, or time by some other name, like duration, or change.  Maybe it is not a question of reality but a question of usefulness of conceptualisation.  Maybe strings don't exist, but are a useful mathematical tool to conceptualise subatomic matter. Maybe we could say the same for time, it is a convenience for something we don't actually understand, but the fact of locality and variation in the beatings of said caesium atoms requires us to incorporate time as a dimension into conceptual models otherwise we sacrifice authenticity. 

Sorry, brain starting meltdown now, knew it was a mistake to get into this .... 

No problem .. I think you are exactly right.

[floo]

I have wondered for a long time if time is circular, there is no past, present or future as such. We all act out our lives on our own bit of the time circle, just a thought.

[wigginhall]

Excellent points by torridon.  If you go looking for an objective thing called time, you will go mad, and you will end up drinking heavily every afternoon.   The pragmatic solution is well, a pragmatic one, or an instrumental  one.   Isn't this true of most things? 

Self?   Damn, where's that bottle. 

[Sriram]

Well...this discussion has gone into philosophical musings about perception, Buddhism and so on.  All that is fine. Whether life really is all about perception or not and whether life is an illusion or not is a different discussion.

In this thread, my point about Time being merely a human construct is about a fact which we tend to miss. We have gotten used to thinking of Time as some real, eternal and abstract dimension of the universe that causes things to change.  My point is that things change due to internal reasons or external influences. There is no need to resort to anything like an endless Time that causes all these things.

As I have mentioned above, changes happen by themselves.....and when we measure them or perceive them as Past, Present and Future...we create Time as a convenient tool or  canvas in our minds. But in reality there is no reason to believe that here is anything like Time in existence.   

Whatever Time dilation and other observations that have been made due to the effects of gravity and motion etc. will be equally valid if perceived as effects on Change rather than on Time....because Time is nothing but rate of Change.

There is however a possible benefit of thinking of it as Change rather than as Time. If we think of the effects of gravity in slowing down Time, it remains abstract.....as a strange and mysterious phenomenon. 

If however we think of it as the effect on Change rather than on Time, we have the possibility of investigating the reasons for the slowing down of Change, because Change is caused by internal or external influences. So we can find out why and how these influences change due to gravity. 

Just some thoughts.

[ekim]

What do you meant by "rates" if there is no time?

In this context, I think what is meant is observable relative rates of change e.g. growth, decay, velocity etc., without the need of measurement in terms of an invented concept of time.

[Nearly Sane]

In this context, I think what is meant is observable relative rates of change e.g. growth, decay, velocity etc., without the need of measurement in terms of an invented concept of time.

And how would you measure relative here? Would you measure velocity without speed?

[Nearly Sane]

Is there a set of invisible posts here about time being a cause?

[ekim]

I think that this is s strawman. I haven't seen anyone suggest there is an entity called time. And in exactly the same way, there isn't an entity space but time is simply a description of the dimension in which things change, just as space is the dimension in which they move.

The question is about whether time is purely a construct of the mind or is an inevitable way of experiencing.

No straw man intended, but perhaps I misunderstood your assertion that 'change needs time'.  If the question is as you say then perhaps it is both a construct of the mind and has become an inevitable way of experiencing.

[Nearly Sane]

No straw man intended, but perhaps I misunderstood your assertion that 'change needs time'.  If the question is as you say then perhaps it is both a construct of the mind and has become an inevitable way of experiencing.

Try it as 'movement needs space'. There isn't any sense there of an entity. If there was no dimension of time in what would change happen. If there was no change, it wouldn't mean there was no time. If there was no time how could there be change.

[ekim]

And how would you measure relative here? Would you measure velocity without speed?

In the context of change there is no need to measure, just observe.