# How do we know time flows?

YumClock

Thu 16 Apr, 2009 09:02 pm
@Phosphorous,
Phosphorous wrote:
Hmm... does time flow? I guess flow, in this case, means continuous. For something to be continuous there would have to be infinitely many divisions of it.

Scientists seem to have isolated the smallest instant of possible time through experiment, where it is impossible to divide the instants any further. Thus, time is not continuous. Therefore it doesn't flow, but manifests to us in discrete moments.

Is that so hard to understand?

I think this is a wonderfully logical post.
I simply cannot imagine a smallest increment, though.
Assuming the Planck length is indeed the smallest, I don't see why you couldn't hold it up and cut it in half. In a literal sense, there may be nothing small enough to cut it, but mentally it could be done.
The same goes with the unit of time you mentioned.

I know that I'm wrong, by the way, in thinking this. Can anyone convince me otherwise?

Fri 17 Apr, 2009 12:00 pm
@YumClock,
Quote:
I know that I'm wrong, by the way, in thinking this. Can anyone convince me otherwise?

Are you measuring time or are you counting arbitrary hash marks of measurement? The unit of measurement is not of time it is of the unit. When measuring a plank you are not measuring a plank you are measuring the tape and cutting the plank where the tape's hash marks imply that you should. Yet with something non-physical like time there is really nowhere to cut. It is all measurment hash marks and no object to measure. We have a sense of duration that we can mark from memory experience point A to memory experience point B but no memory of the inbetween. This either leaves time as a human construct of measurement or a flowing thing unmeasurable or both. We assume that because we can remember experience point A that there must have been some sort of duration between then and Experience point B because we remember that A happened before B. One might say well duh A happened before B so that shows a chronology, however it only shows a chronology of abstract memory points. Some evidence for time flowing and not being measurable comes in sayings based from experiential duration like, "Time flies when you're having fun," and "man this day is just dragging on". Now these show that your personal relationship with time is not in its measurement but in its flow in relation to your experience between memory point A and memory point B. The arbitrary measurement marks on the clock went by at the same measurement rate that they would go in either situation but your experience with time was completely different with one experience turning 5 hours into 30 minutes of arbitrary measurement and the other turning 5 hours into 12 hours of arbitrary measurement, as example. So what it comes down to is whether you trust your experience of duration or you trust your training of "time"

Alan McDougall

Mon 27 Apr, 2009 11:27 am
The only way of knowing whether time flows is to relate it to movement. If all objects in the cosmos froze to absolute zero, could time be expressed.?

If we could freeze or stop every object in the universe, like the earth stopped moving around the sun, the sun frozen in its orbit around the galaxies, the galaxies no longer moving or expanding ,the universe static and still, how could time be measured?

We need moved to make any concept of time meaningful, everything is relative, nothing is absolute

Alan

validity

Mon 27 Apr, 2009 05:38 pm
@xris,
xris wrote:
So does the fly stop or not?If it does not stop how does it change direction without stopping..I still claim its not if it stops, its for how long..The law of logic demands it stops..
I think the answer lies somewhere with the idea that if time is discrete, like the rungs on a ladder, there is no way to describe what happens to change the direction of the fly in the same manner you can not climb the ladder by using the space between the rungs. It is an instantanoues change, there is no stopping for any duration of time, since there is no time (or rungs) between the discrete steps (or that it is meaningless to attempt to describe time between the discrete steps)

xris

Tue 28 Apr, 2009 03:16 am
@validity,
validity wrote:
I think the answer lies somewhere with the idea that if time is discrete, like the rungs on a ladder, there is no way to describe what happens to change the direction of the fly in the same manner you can not climb the ladder by using the space between the rungs. It is an instantanoues change, there is no stopping for any duration of time, since there is no time (or rungs) between the discrete steps (or that it is meaningless to attempt to describe time between the discrete steps)
Sorry but its nothing like climbing a ladder, the feet stop but the body is continuing its journey.Time is the knowing.Imagine if an object is moving extremely slowly, almost undetectable and then it slows even more, at some point we by our perspective assume its not moving.Now is movement calculated by your infinitely small measurements of time or is time an amazing illusion.Imagine a rock on the surface of the moon or distant planet.It moves half an inch in a billion years, is it moving or has it stopped.Those movements are expressed in the fly changing direction,it can be seen at any speed very fast or extremely slowly.Time is the illusion.

validity

Tue 28 Apr, 2009 04:52 am
@xris,
xris wrote:
Sorry but its nothing like climbing a ladder, the feet stop but the body is continuing its journey.Time is the knowing.
I think, as far as an analogy goes, it is perfectly acceptable. You can not place your feet between the rungs and climb the ladder, your feet must have certain discrete locations, in effect the height you reach as you climb the ladder is quanitised. You state "its not if it stops, its for how long.." the rung-analogy provides an answer i.e it is incorrect to think how long does it stop for as there is no time interval shorter, it could appear instantaneous. It is analogous to saying how high off the ground are you if you stand on rung 0.5, you can not, your height off the ground is either 0 rung or 1 rung, there can not be height = 0.5 rung

xris wrote:
Now is movement calculated by your infinitely small measurements of time or is time an amazing illusion.
Or time can be discrete, in which case the idea of infinitely smaller units of time can be abandoned.

xris

Tue 28 Apr, 2009 06:54 am
@validity,
validity wrote:
I think, as far as an analogy goes, it is perfectly acceptable. You can not place your feet between the rungs and climb the ladder, your feet must have certain discrete locations, in effect the height you reach as you climb the ladder is quanitised. You state "its not if it stops, its for how long.." the rung-analogy provides an answer i.e it is incorrect to think how long does it stop for as there is no time interval shorter, it could appear instantaneous. It is analogous to saying how high off the ground are you if you stand on rung 0.5, you can not, your height off the ground is either 0 rung or 1 rung, there can not be height = 0.5 rung

Or time can be discrete, in which case the idea of infinitely smaller units of time can be abandoned.
Sorry but appear to be contradicting yourelf.

validity

Tue 28 Apr, 2009 04:28 pm
@xris,
xris wrote:
Sorry but appear to be contradicting yourelf.
I hope not :perplexed:

EDIT

I thought of another way to think of what is happening and that is to realise that objects are not rigid. The leading edge of a tennis ball, as it hits a tennis racket, slows down before the trailing half. The opposite, but equal force of the tennis racket makes the part of the ball change direction prior to the entire ball changing direction.

xris

Wed 29 Apr, 2009 02:39 am
@validity,
validity wrote:
I hope not :perplexed:

EDIT

I thought of another way to think of what is happening and that is to realise that objects are not rigid. The leading edge of a tennis ball, as it hits a tennis racket, slows down before the trailing half. The opposite, but equal force of the tennis racket makes the part of the ball change direction prior to the entire ball changing direction.
Constant movement is an object moving from one location to another it has to move in increments otherwise it would be in two places at the same time.Its a matter of accepting time is the measurement of action.As you cant see time moving, we only ever see snippets of time and they are not divisible or enlargeable.Instants of time recorded by movement.The speed of movement confuses the observer into thinking time moves at different speeds,as you know it does not.So the fly stops, its how long for? is the only question.

validity

Wed 29 Apr, 2009 02:53 am
@xris,
Hello xris.

I will leave
xris wrote:
The speed of movement confuses the observer into thinking time moves at different speeds,as you know it does not.
until later as I firstly want to understand your view
xris wrote:
So the fly stops, its how long for? is the only question.
first.

I would like to understand what it means when you say the fly stops. As the fly hits the train its head will stop first, the transfer of momentum from the train will cause its head to then move backwards. The problem for the fly is that the relativily large momentum of the train means its head is going to be travelling in the opposite direction well before the rest of its body is.

Various parts of the fly stop at different times. So what does it mean to say the fly stops?

xris

Wed 29 Apr, 2009 03:11 am
@validity,
validity wrote:
Hello xris.

I will leave until later as I firstly want to understand your view first.

I would like to understand what it means when you say the fly stops. As the fly hits the train its head will stop first, the transfer of momentum from the train will cause its head to then move backwards. The problem for the fly is that the relativily large momentum of the train means its head is going to be travelling in the opposite direction well before the rest of its body is.

Various parts of the fly stop at different times. So what does it mean to say the fly stops?
..Hello Validity..It means exactly that.What if it was another train colliding with my train?Would you say the front would crumple and the last carriage would follow the previous carriage and they would all stop at different times?If one had more mass than the other and more speed it would overcome the lighter and slower train and push it backwards.Before it pushed it backwards they would both stop, for considerable longer than when my train hit the fly but stop they do.Xris..

etcetcetc00

Wed 29 Apr, 2009 08:52 am
@xris,
xris;60457 wrote:
Constant movement is an object moving from one location to another it has to move in increments otherwise it would be in two places at the same time.Its a matter of accepting time is the measurement of action.As you cant see time moving, we only ever see snippets of time and they are not divisible or enlargeable.Instants of time recorded by movement.The speed of movement confuses the observer into thinking time moves at different speeds,as you know it does not.So the fly stops, its how long for? is the only question.

Umm, time does move at different speeds. It's called 'relativity'. There was this really smart guy named Albert Einstein. He figured that one out. It changes relative to speed and gravity.

xris

Wed 29 Apr, 2009 10:46 am
@etcetcetc00,
etcetcetc00 wrote:
Umm, time does move at different speeds. It's called 'relativity'. There was this really smart guy named Albert Einstein. He figured that one out. It changes relative to speed and gravity.
Time moves at the same time relative to the objects we are debating.You tell me when you have seen time change speed.Einsteins theory is hypothetical when speaking of the speed of light not our earthly experience.Gravity affects time but with constant gravity time does not change its speed.If you know the secret let me know and i might let my kids catch me up.

validity

Wed 29 Apr, 2009 09:43 pm
@xris,
xris wrote:
What if it was another train colliding with my train?Would you say the front would crumple and the last carriage would follow the previous carriage and they would all stop at different times?
Yes, since there are no rigid objects.

xris wrote:
If one had more mass than the other and more speed it would overcome the lighter and slower train and push it backwards.Before it pushed it backwards they would both stop, for considerable longer than when my train hit the fly but stop they do.Xris..
I can not understand how both would stop. The lighter and slower train does not have enough momentum (product of the mass and velocity) to stop a larger faster train. It does have enough momentum to alter the velocity part of the mometum of the larger faster train and perhaps crumple part of the larger faster train, but to stop it no.

YumClock

Wed 29 Apr, 2009 11:09 pm
@etcetcetc00,
I apologize for not directly following the conversation, but...
If time didn't flow regularly, noone would notice, because you'd see life in slow motion while you're in slow motion, therefore you'd see everything at the same speeds.

Time is integral to motion, as without time motion could not occur. So humans can tell time not only by memory but by motion.

validity

Wed 29 Apr, 2009 11:38 pm
@YumClock,
YumClock wrote:
If time didn't flow regularly, noone would notice, because you'd see life in slow motion while you're in slow motion, therefore you'd see everything at the same speeds.
That is true for what is called your frame of reference, but it is possible for another person who is in a different frame of reference to see you in slow motion.

I need to correct myself
validity wrote:
Yes, since there are no rigid objects.

I should of said

Quote:
Yes, since there are no rigid trains.

bioharmony

Thu 30 Apr, 2009 02:29 am
@validity,
To answer this question I would like to use the following definition. It is a traditional medical or linear definition:
[CENTER][CENTER] [/CENTER][/CENTER]
'Consciousness is the critical biological function
[CENTER][CENTER] that allows us to know sorrow, or know joy, [/CENTER]
[CENTER]to know suffering or know pleasure.'[/CENTER]
[CENTER] Prof Antonio Damasio [/CENTER][/CENTER]

If time or the flow of time is part of our consciousness (as defined by the above definition) then outside of our consciousness time/flow of time does not exist. Time may also slow for our biological consciousness. For example, there many stories of people who experience time 'slowing down' when they were in a stressful or dangerous situation (for example).

xris

Thu 30 Apr, 2009 03:15 am
@validity,
validity wrote:
Yes, since there are no rigid objects.

I can not understand how both would stop. The lighter and slower train does not have enough momentum (product of the mass and velocity) to stop a larger faster train. It does have enough momentum to alter the velocity part of the mometum of the larger faster train and perhaps crumple part of the larger faster train, but to stop it no.
Alter the velocity ,what is velocity?what is stopping what is moving?I will up the anti..two trains equal speed equal weight.They collide head on,logic will tell us they both stop ,agree?Now one is a minute gramme heavier than the other, what happens.Another thought a fly manages to get up to an incredible speed and smashes into a motionless train, what happens?What happens as the fly gets bigger and faster? Velocity alters the time not the logic.
We only ever see now,we don't see the past ,we remeber it.We never see the future we imagine it.We only see time at the instant it occurs, its our mind that creates the illusion of it flowing.The train hitting the fly is that instant, it is frozen in that moment,a moment that cant be divided or enlarged.

validity

Thu 30 Apr, 2009 04:37 am
@xris,
xris wrote:
Alter the velocity ,what is velocity?
Velocity is how fast something is going and in what direction eg 100km/h due East.

xris wrote:
what is stopping what is moving?
I am trying to understand what you mean when you say the fly/train etc stops.

xris wrote:
I will up the anti..two trains equal speed equal weight.They collide head on,logic will tell us they both stop ,agree?
I disagree, demonstrated here YouTube - Newton's cradle - Newtonin kehto at 34 seconds.

xris wrote:
Now one is a minute gramme heavier than the other, what happens.Another thought a fly manages to get up to an incredible speed and smashes into a motionless train, what happens?What happens as the fly gets bigger and faster?
It depends on relationship between both objects momentum. Generally, the object with the most momentum wins.

xris wrote:
We only ever see now,we don't see the past ,we remeber it.We never see the future we imagine it.
I got one too... "Today is tomorrows past and yesterdays future"

xris wrote:
We only see time at the instant it occurs, its our mind that creates the illusion of it flowing The train hitting the fly is that instant, it is frozen in that moment,a moment that cant be divided or enlarged
If time does not flow (in some or any sense), why/how do things change?

xris

Thu 30 Apr, 2009 05:44 am
@validity,
I don't think your demonstration helps you, it helps me.When the ball impacts on the stationary ball does a ball stop?If you have one stationary and one moving the one that stops obviously stops and one was stopped already.Both had no motion but one maximum potential.A bit like the pendulum at its point of turn.The fly had stopped like the train but the train had all the potential.
If you look at a river the water is moving down river by the action of gravity, it flows. The activity that gives us time is not moving its changing.Time itself is not going somewhere it is just happening,this occurrence is now it wont happen again or further ahead in time.