NationStates Jolt Archive

Time has no existence apart from the human mind, as a concept, yet people point to a clock and its precise measurements and claim that the progression in consistent increments indicates an absolute.

Is time absolute?

Of course time is relative. It gets slower the closer you move to a gravity well.


To answer more philosophically, of course, then time is relative also. I found I can practically manipulate it, faster or slower, by considering the value of a second,and percieving it as actually quite a quick passage, or a slower passage.

Only good on long train journeys, I assure you. Otherwise, you forget about it and you fall victim to the whims of father time again. Curse him.

Of course time is relative. It gets slower the closer you move to a gravity well.

Or when moving with speeds approaching c.

Time does pass and can be measured, so it has an independant existence. Though admittedly our everyday perception of what time is can be argued to exist only in our minds ;)

Time has no existence apart from the human mind

In word, pure truth. In meaning, utter nonsense. Just because we've put a name on something doesn't mean it wouldn't exist if we weren't here to do so. Or would other abstract concepts like distance not exist without humans to perceive them? What you claim is that because we have devised a way of measuring time as it passes that way must automatically not be an accurate representation of the Universe. What, then, do clocks measure? The answer is that they don't measure anything - they're not like tape measures, which you can attach to something solid and use to prove it's 5cm long. They don't measure at all, they count, and we use them to measure the distance in time between one event and another. Time exists the same way as distance exsts; it's a distance between two events. It measures change; without change there would be no time, but without humans things would still change, and that change would not happen instantaneously: if a rock rolled down a hill and took no time whatsoever to do so, it would exist at every point along the line simultaneously. The rock must go from A to B, and since it does not do so instantaneously a name must be given to the phenomenon which differentiates its fall from another rock, which rolls much more slowly.

In that regard, then, "absolute"; it is certainly not relative to the human mind, no matter how cleverly one attempts to argue it. As for relative-to-space, I'll have to leave that one to the physicists. The much more interesting question is this: Are there moments in time? (http://en.wikipedia.org/wiki/Zeno%27s_paradoxes)

Well, science is a lot easier than philosophy, so the actual answer to your question is:

Time is relative. Cos Einstein said so.

Of course time is relative. It gets slower the closer you move to a gravity well.
Alright, but the way you have worded it here indicates that time is something physically real, subject to the effects of gravity and therefore with an absolute existence.

Relative. Try waiting in the hospital for your goddamn medicine for 45 minutes. Then try flying at the speed of light for 45 minutes.

Then eat for 45 minutes.
Then stare at a clock for 45 minutes.
Get your ass kicked for 45 minutes.

*ass implodes*

Time is relative. Cos Einstein said so.

Which is a falicious appeal to authority. *Sigh*.

Time is an absolute, because it can be measured.

Much like light is both particle and wave, Time is both absolute and relative.

Now that, that is all cleared up, I'll move on :cool:



:D

Time is an absolute, because it can be measured.

My measurement, Mr. I-Still-Believe-in-an-Aether, will be different from yours if I am travelling through spacetime. Thou dost not know of what thou speakest.

My measurement, Mr. I-Still-Believe-in-an-Aether, will be different from yours if I am travelling through spacetime. Thou dost not know of what thou speakest.

Are you being facetious or does he really still believe in the aether?

Anyway, time is an absolute in that it is a dimension of our universe which we can measure. It varies along with mass and length in a relative way (different meaning of the word relative here), meaning it is at least partially related to them.

In word, pure truth. In meaning, utter nonsense. Just because we've put a name on something doesn't mean it wouldn't exist if we weren't here to do so. Or would other abstract concepts like distance not exist without humans to perceive them?
The "distance" as we understand it would not be changed, but there would be no measurement without an agent to understand what is being measured. So, yes; you cannot remove the consciousness from this "equation" and have it mean the same thing.

What you claim is that because we have devised a way of measuring time as it passes that way must automatically not be an accurate representation of the Universe.
Representation to whom? It may well be accurate, but without someone to represent it to, it is all meaningless.

What, then, do clocks measure? The answer is that they don't measure anything - they're not like tape measures, which you can attach to something solid and use to prove it's 5cm long. They don't measure at all, they count, and we use them to measure the distance in time between one event and another. Time exists the same way as distance exsts; it's a distance between two events. It measures change; without change there would be no time, but without humans things would still change, and that change would not happen instantaneously: if a rock rolled down a hill and took no time whatsoever to do so, it would exist at every point along the line simultaneously. The rock must go from A to B, and since it does not do so instantaneously a name must be given to the phenomenon which differentiates its fall from another rock, which rolls much more slowly.
You asked, What do clocks measure, claim they measure nothing and then proceed to state what they measure. Well done.

You are correct: without humans, events would still progess. That isn't the claim being made, though. "Time" is that measure of that interval between events, and measurement is only meaningful to a consciousness. Look, you yourself have demonstrated it with "and took no time whatsoever to do so." If there were no "time", those events would not suddenly squish together in the "timeline", because all time is is a human measure; all that would really change is that there would be no one to label the interval between them.

You are correct: without humans, events would still progess. That isn't the claim being made, though. "Time" is that measure of that interval between events, and measurement is only meaningful to a consciousness. Look, you yourself have demonstrated it with "and took no time whatsoever to do so." If there were no "time", those events would not suddenly squish together in the "timeline", because all time is is a human measure; all that would really change is that there would be no one to label the interval between them.

The interval we measure is "minutes, seconds, days" etc, time itself is a dimension of measurement.

Time is indeed relative. While I'd always suspected, a mushroom trip last weekend confirmed my suspicions. :p

The interval we measure is "minutes, seconds, days" etc, time itself is a dimension of measurement.
That's meaningless to me. Can you elaborate?

Ah. I see I have misunderstood you, Willamina. Your definition of "time" is, roughly: "a measurement of the change which takes place between two events." Is this accurate? Because if so, then A) it becomes fairly difficult to debate the point, as our language can't really cope with such things, and B) yes, evidently, since measurements are things which require a measurer, "time" is relative to the human mind.

I think what most others here would debate is your meaning of the word "time," which they would take to mean the property of the change itself, not the measurement of it.

P.S.: Forgive me for being slightly short in my previous post, it sounded like you'd come out with an absurd "I'M A PHILOSOFER!!!!!11" claim until I understood you better. :fluffle:

There are two ideas that are juxtaposed in our concept time. One of these probably exists, the other may not, and simply be a construction that our awareness uses to impose order on our perceptions.

The first one, being the sequence of earlier and later events. This is what time is in the physics world, as time of an event only has meaning with respect to another if the light cone from that first named event includes the second event.
If the second event is outside of the light cone of the first event (here first and second being used just as labels, not as temporal references) then there is no sequential relationship between the two events. It is not possible to determine what order they occurred in. (Weird idea I know, but how time works in physics)

The second idea is of a continuum that is there and marked by labels such as 13:57:16 on Monday 30th May 2005. This is clearly artificial, both in the existence of the continuum, independent of any events, and in the labelling. What a clock does is define events (The hand pointing to the number event) that are used to create this continuum as a communal experience instead of as an inherently private and internal experience. (Subjective time made objective by an event producing machine, a clock)

Thank you, New Watenho. I have the answer I was seeking thanks to your post. I know how I'll respond to the question, next time I face it.

Time is absolute, and it is also relative. There are two things going on, not just one, and the reason for that is that events are being perceived and interpreted by a consciousness. Events do progess apart from us, that is indisputable; however, we perceive the progression and give it a label, making it meaningful to us. Two perspectives, the objective and the subjective, operating at the same time.

I knew this... just had forgotten.

That's meaningless to me. Can you elaborate?

Ok, imagine you plan to meet someone. They give you a set of three numbers that designate where you are to meet them: the two intersecting streets on which the building is located (x,y) and the floor of the building they are on (z).

You go to meet them and find out they left yesterday. They left out one crucial number, the time (t).

You see, our universe exists in four dimensions, three spatial dimensions (x,y,z) and one temporal dimension (t).

Using these together, any point in all of existance can be specified.

There are two ideas that are juxtaposed in our concept time. One of these probably exists, the other may not, and simply be a construction that our awareness uses to impose order on our perceptions.

The first one, being the sequence of earlier and later events. This is what time is in the physics world, as time of an event only has meaning with respect to another if the light cone from that first named event includes the second event.
If the second event is outside of the light cone of the first event (here first and second being used just as labels, not as temporal references) then there is no sequential relationship between the two events. It is not possible to determine what order they occurred in. (Weird idea I know, but how time works in physics)

The second idea is of a continuum that is there and marked by labels such as 13:57:16 on Monday 30th May 2005. This is clearly artificial, both in the existence of the continuum, independent of any events, and in the labelling. What a clock does is define events (The hand pointing to the number event) that are used to create this continuum as a communal experience instead of as an inherently private and internal experience. (Subjective time made objective by an event producing machine, a clock)
Thank you. :)

Ok, imagine you plan to meet someone. They give you a set of three numbers that designate where you are to meet them: the two intersecting streets on which the building is located (x,y) and the floor of the building they are on (z).

You go to meet them and find out they left yesterday. They left out one crucial number, the time (t).

You see, our universe exists in four dimensions, three spatial dimensions (x,y,z) and one temporal dimension (t).

Using these together, any point in all of existance can be specified.

Even being able to define a spatial point that way requires an agreed origin and agreed units of measure. A fixed point. Or it requires a naming convention for spatial objects such as streets. Time has the same problems. What is going to be your origin, what are going to be the units of measure. There is no absolute possible as events in the universe are temporaly disconnected. The origin has to be local. How this can be definesd is unclear. Then what units of measure are you going to use and how are you going to ensure that these are equivalent for all observers.

Sorry, it is a lot more complicated than using cartesian or even polar co-ordinate systems.

Thank you, New Watenho. I have the answer I was seeking thanks to your post. I know how I'll respond to the question, next time I face it.

I do my best. Glad to have been of service. I'll be here all week, folks! :p

Ah, I see what's going on. I had forgotten, as our friend Willamena here, the dual nature of time. Forgive me.

Is time absolute or relative?

Time is absolutely relative. It is also relatively absolute.

Even being able to define a spatial point that way requires an agreed origin and agreed units of measure. A fixed point. Or it requires a naming convention for spatial objects such as streets. Time has the same problems. What is going to be your origin, what are going to be the units of measure. There is no absolute possible as events in the universe are temporaly disconnected. The origin has to be local. How this can be definesd is unclear. Then what units of measure are you going to use and how are you going to ensure that these are equivalent for all observers.

Sorry, it is a lot more complicated than using cartesian or even polar co-ordinate systems.

It still gets the basic idea across that time isn't something we created by is a cohesive part of the universe in the exact same way length, heigh, and width are.

You are correct: without humans, events would still progess. That isn't the claim being made, though. "Time" is that measure of that interval between events, and measurement is only meaningful to a consciousness. Look, you yourself have demonstrated it with "and took no time whatsoever to do so." If there were no "time", those events would not suddenly squish together in the "timeline", because all time is is a human measure; all that would really change is that there would be no one to label the interval between them.
:rolleyes: Yes, Willamena, time exists, but the units to measure time are a human creation and therefore meaningless to a non-human. An alien would use different units.

time only exst as long as we are alive.becous in the universe time is moer extenscev in the hole universe. so we as humans crated clooks that are bacist off earth time and thta is basct off how are planet rowtaets and so on os in all respect time is relative to the persion and his or her pont of view. but in the universe time is so vast that it becoumse inpasebel to mesher that amont of time and all so that macese these how then a human problem and time is relative to us becouse we live only a short time conperd to the hole pecsher that being the universeor the earth.

Even being able to define a spatial point that way requires an agreed origin and agreed units of measure. A fixed point. Or it requires a naming convention for spatial objects such as streets. Time has the same problems. What is going to be your origin, what are going to be the units of measure. There is no absolute possible as events in the universe are temporaly disconnected. The origin has to be local. How this can be definesd is unclear. Then what units of measure are you going to use and how are you going to ensure that these are equivalent for all observers.

Sorry, it is a lot more complicated than using cartesian or even polar co-ordinate systems.
The only absolute is "now"?

Relatively absolute...

Time is a way of measuring our progression around the sun. It takes approximately 365 days (dropping fractions) to travel that distance. A day is measured as one complete rotation of the planet. Days are then broken into hours (24), which are broken into minutes (60), and minutes into seconds (60).

To remove references to the measurement of time:
It takes approximately 365 rotations of the 3rd planet of Sol, for it to complete it's journey around the sun.

The above statement does not change. If it did, we would notice it from the momentum created by us hurtling through space as we do. Basically, it would be noticed as a reduction or increase in gravity on the front and back sides of the planet (front and back are in reference to direction of travel in the Earth's orbit). Since gravity at sea level remains at approximately 1G, with slight variations due to shifting density of the mass of the planet, and is completely inconsistant with the noticable effect of accelerating or decelerating force, it is clear that Earth's velocity does not, in fact, change.

All of the above implies an absolute.

Aside: BTW, Earth's velocity is some 30km/sec (I forget the exact number)...that's really fast!

Now, on to why I say "relatively absolute". One of our most common methods of measuring time is through measuring the vibration of atoms in crystals (typically quartz). In a strong gravity well, such as created by Earth, these crystals will remain consistant in their atomic vibrations. Once removed from such a gravity well, an apparent "time acceleration" is noticed. As someone above mentioned, time slows as you enter a strong gravity well. It is my theory that it is not time that is slowing, merely one of our methods of measurement becomes more inaccurate as it is removed from the gravity well we typically stand within. Why is this relavent? Because human perception of time is highly based on these devices. If a clock seems to be moving faster, we quite often move faster with it. If a clock moves slower, we tend to move slower with it as well.

In otherwords, time as a measurement of the Earth's movement is completely absolute. Human perception of time is based completely on human perception, which is relative to the individual, and often relative to the device used for measurement.

time is eternal and utterly inseperable from space. in my opinion it is quite often distracting in that daydreams of the future and nostalgia over the past remove our attention from the present, which is the only place where we truly have any form of agency. i probably sound like a damn hippy but the only absolute is the eternal moment, which can only be realized after illusions and misconceptions about the true nature of time are removed. there is no independently existing "past" or "future".

It still gets the basic idea across that time isn't something we created by is a cohesive part of the universe in the exact same way length, heigh, and width are.

Well maybe it would if it worked and time was a cohesive part of the universe, but it doesn't and time isn't.

That events within a causal limit light cone are sequential is part of our understanding of the universe. This means that we can establish one event as prior to another event. It does not mean that we can presume a continuum of some mysterious form between one event and the next event in that causally connected region. Time is not necessarily continuous, it is probably quantised or we have serious problems with energies going to infinity instantaneously etc.. Now in the intervals between quanta of time the universe in our region still exists, it does not flash into and out of existence, but time does not exist in this interval so time is not inherent to the universe.

This does not, however make time a coherent part of the universe. It makes it a purely local phenomenon that may or may not act in similar ways in other causally linked regions. We do not know and we can not know this.

Where did you leave the lemon?
On your mother! you mother!

The only absolute is "now"?

In a subjective sense I suppose. What is "now" for a sentient being in one light cone region has no reason whatsoever to be thought of as being the same moment of time as the "now" for a sentient being in a disconnected region.

time only exst as long as we are alive.becous in the universe time is moer extenscev in the hole universe. so we as humans crated clooks that are bacist off earth time and thta is basct off how are planet rowtaets and so on os in all respect time is relative to the persion and his or her pont of view. but in the universe time is so vast that it becoumse inpasebel to mesher that amont of time and all so that macese these how then a human problem and time is relative to us becouse we live only a short time conperd to the hole pecsher that being the universeor the earth.
Dispite the atrocious spelling ;) I agree with the ideas expressed here. I tend to "default" to the perspective of the individual consciousness, perhaps because I am one, and not trained to see otherwise. Time has no real meaning for me apart from being a measurement for a consciousness to manipulate itself.

alien born, you keep using the phrase "light cone", but would you mind elaborating a bit on it? my guess is that it's a sort of conceptual tool, but i feel that without properly understanding it i'm missing your point.

Dispite the atrocious spelling ;) I agree with the ideas expressed here. I tend to "default" to the perspective of the individual consciousness, perhaps because I am one, and not trained to see otherwise. Time has no real meaning for me apart from being a measurement for a consciousness to manipulate itself.
I agree with this from the philosophical point of view. A conciousness has a need to find its place in the Universe; and since the Universe doesn't really give a hoot, it has to create its own definitions, to create a place for itself.

Time itself, of course, is one, and the perception of the motion of time is relative.

There are, however, more aspects than just unity and relativity.
For example, the idea of branching time. With each new event, there are an infinite number of outcomes, and there are an infinite number of events. Each time you make a decision, you change that path. This is the idea of a 'light cone,' explained by Stephen hawking in A brief History of Time. It is a cone, percieving time as an object, in that with each new branch, it is expanded.

aline born you got waht i was saying and got my theroy kodos to you.

Well maybe it would if it worked and time was a cohesive part of the universe, but it doesn't and time isn't.

That events within a causal limit light cone are sequential is part of our understanding of the universe. This means that we can establish one event as prior to another event. It does not mean that we can presume a continuum of some mysterious form between one event and the next event in that causally connected region. Time is not necessarily continuous, it is probably quantised or we have serious problems with energies going to infinity instantaneously etc.. Now in the intervals between quanta of time the universe in our region still exists, it does not flash into and out of existence, but time does not exist in this interval so time is not inherent to the universe.

This does not, however make time a coherent part of the universe. It makes it a purely local phenomenon that may or may not act in similar ways in other causally linked regions. We do not know and we can not know this.


Basically what you're saying is that we cannot prove that time acts in the same way or even exists in an disconnected region arbitrarily distant from our current position?

This is where we operate under the same general assumption we do with the rest of physics: we have never observed it act in any way different than what we can scientifically explain will happen under given conditions so it is held as truth that it will act this way in all locales until we observe it acting in some seperate way.

I do, however, agree with you that time is quantitized (as is space). Nothing below the Planck time is effectivily observable so it is assumed to not exist as it provides no evidence of such existance. The same applies to things below the planck length.

To the one guy:

It has nothing to do with our instruments in gravity wells. In reality, time is, just as very much of the universe, a function of light. For instance, imagine you have a light clock (two reflective surfaces with a single photon bouncing between them with each bounce counting as a discrete "tick"). Since we know gravity can warp spacetime, this will effect the photon's path, effectivily making it vary directly with the strength of the gravitational field.

However, the speed of light (and thus a photon) is absolute in all reference frames, so this means that the ticks themselves slow, leading the slowing of time itself. The person in control of the experiment will not notice the slowing due to the fact that they are effected by it themselves. An outside observer, however, will notice this change.

Basically what you're saying is that we cannot prove that time acts in the same way or even exists in an disconnected region arbitrarily distant from our current position?

This is where we operate under the same general assumption we do with the rest of physics: we have never observed it act in any way different than what we can scientifically explain will happen under given conditions so it is held as truth that it will act this way in all locales until we observe it acting in some seperate way.

I do, however, agree with you that time is quantitized (as is space). Nothing below the Planck time is effectivily observable so it is assumed to not exist as it provides no evidence of such existance. The same applies to things below the planck length.

To the one guy:

It has nothing to do with our instruments in gravity wells. In reality, time is, just as very much of the universe, a function of light. For instance, imagine you have a light clock (two reflective surfaces with a single photon bouncing between them with each bounce counting as a discrete "tick"). Since we know gravity can warp spacetime, this will effect the photon's path, effectivily making it vary directly with the strength of the gravitational field.

However, the speed of light (and thus a photon) is absolute in all reference frames, so this means that the ticks themselves slow, leading the slowing of time itself. The person in control of the experiment will not notice the slowing due to the fact that they are effected by it themselves. An outside observer, however, will notice this change.

Perfect! Thank you, that was a beautiful explanation. One nitpick - if you check out this month's SciAm, you'll see the speed of light, it turns out, may not have always been what it is today. It is not necessarily constant! (freaky, huh?)

There are, however, more aspects than just unity and relativity.
For example, the idea of branching time. With each new event, there are an infinite number of outcomes, and there are an infinite number of events. Each time you make a decision, you change that path. This is the idea of a 'light cone,' explained by Stephen hawking in A brief History of Time. It is a cone, percieving time as an object, in that with each new branch, it is expanded.

thanks, just what i was looking for.

Well maybe it would if it worked and time was a cohesive part of the universe, but it doesn't and time isn't.

That events within a causal limit light cone are sequential is part of our understanding of the universe. This means that we can establish one event as prior to another event. It does not mean that we can presume a continuum of some mysterious form between one event and the next event in that causally connected region. Time is not necessarily continuous, it is probably quantised or we have serious problems with energies going to infinity instantaneously etc.. Now in the intervals between quanta of time the universe in our region still exists, it does not flash into and out of existence, but time does not exist in this interval so time is not inherent to the universe.

This does not, however make time a coherent part of the universe. It makes it a purely local phenomenon that may or may not act in similar ways in other causally linked regions. We do not know and we can not know this.
These ideas are new to me, beyond the scope of what I'd asked but utterly fascinating!

Do you have any recommended reading suggestions, perferably at a layman's level.

Time as a dimensionis of course a canstant. But our perseption of time is relative, it depends upon several factors including relative sped and your state of mind. There is the clasic 'Time flies when you are having fun' to prove this point.

These ideas are new to me, beyond the scope of what I'd asked but utterly fascinating!

Do you have any recommended reading suggestions, perferably at a layman's level.

A Brief History of Time, Stephen Hawking. Essential.
The Elegant Universe, Brian Greene. Is mostly about string theory (which is absolutely astounding), but the first few chapters deal all about time dilation and relativity.

These ideas are new to me, beyond the scope of what I'd asked but utterly fascinating!

Do you have any recommended reading suggestions, perferably at a layman's level.

Hawking is as good as any. See the link in the post by Gnomish Dawnsdale (Thank you Gnomish, I was just going to start searching for a link that explained light cones.)

Basically what you're saying is that we cannot prove that time acts in the same way or even exists in an disconnected region arbitrarily distant from our current position?

This is where we operate under the same general assumption we do with the rest of physics: we have never observed it act in any way different than what we can scientifically explain will happen under given conditions so it is held as truth that it will act this way in all locales until we observe it acting in some separate way.

I do, however, agree with you that time is quantitized (as is space). Nothing below the Planck time is effectively observable so it is assumed to not exist as it provides no evidence of such existence. The same applies to things below the Planck length.


Not quite.
What I am saying is that the concept of simultaneity depends upon there being a possible interaction between the two events for this to be meaningful. As this concept is the fundamental concept in time if it can not be established then the temporal relations between such causally disconnected regions are simply arbitrary and meaningless. Thus time is a local phenomenon in a sense that space is not.

It is not denying the assumption of consistency across the universe, it simply claims that any claimed temporal relation between events that are causally isolated will be meaningless. (This is hard to explain)

A little bit like asking which happened first: Froddo finding the ring, or Arrakin turning to the Dark side? The question simply does not make sense.

Is time absolute or relative? Wasn't this question answered by Einstein 100 years ago? It's relative.

Someone said earlier that "now" was the only absolute. Interestingly, "now" isn't even close to being such. Simultaneity, like the measurement of time, is a concept relative to the motion of the observers. There's a good example of why this is true in Greene's Elegant Universe, which is a must for anyone wanting to know more about this.

Is time absolute or relative? Wasn't this question answered by Einstein 100 years ago? It's relative.

No. It was not answered that cleanly. Try reading the thread.

I think time is relative to the human mind and we have identified time with the rise and fall of the sun and moon. We identify time with what we do, what and when we eat, what we like, etc. Time is basically taking control of our being in a way. Then, if you manipulate time in your favor as to change (in your mind) the length of a second, minute, hour, etc. that might not happen.

Not quite.
What I am saying is that the concept of simultaneity depends upon there being a possible interaction between the two events for this to be meaningful. As this concept is the fundamental concept in time if it can not be established then the temporal relations between such causally disconnected regions are simply arbitrary and meaningless. Thus time is a local phenomenon in a sense that space is not.

It is not denying the assumption of consistency across the universe, it simply claims that any claimed temporal relation between events that are causally isolated will be meaningless. (This is hard to explain)

A little bit like asking which happened first: Froddo finding the ring, or Arrakin turning to the Dark side? The question simply does not make sense.

So wait, you're talking branching timelines?

Someone said earlier that "now" was the only absolute. Interestingly, "now" isn't even close to being such. Simultaneity, like the measurement of time, is a concept relative to the motion of the observers. There's a good example of why this is true in Greene's Elegant Universe, which is a must for anyone wanting to know more about this.
The relativity of the "now" (good point btw) makes me remember a theory a friend of mine once devised. Since everything we see needs time to get to us (with the speed of light of course this is very little time, but still there's some) we never really see the "now", we can only see the past. Just as you're looking in the distant past when you look at the stars (because you see the light they send out years ago), you're looking in the past when you look at your computer right now. Even worse, the picture isn't consistent because you see everything in a different time-frame because they are more close to you or further away, just as you can see one star that is one year away and another that is ten years away at the same time! The same goes for all our other senses. Even our brain needs time to get the electrons that "think" around in your head, so you even think in the past. Now in the most literal-scientifical sense of the word is therefore sort of an ideal that we are always running behind, but never overtake. This also proves again the relativety of time of course, but I suppose that wasn't really necessary anymore...

Someone said earlier that "now" was the only absolute. Interestingly, "now" isn't even close to being such. Simultaneity, like the measurement of time, is a concept relative to the motion of the observers. There's a good example of why this is true in Greene's Elegant Universe, which is a must for anyone wanting to know more about this.

that was me (at least one of the people stating such). I'd just like to note that my views are on the nature of time are largely taken from indian/asian religious/philosophical texts in which concepts are often simply pragmatic tools with which to view the world in order to aid one in meditation/yoga.

the way i see it, physics is best/most qualified in attempting to define time "objectively" (which is dubious yet noble from the start, but i won't bother with the usual pomo BS) but as far as reaching an understanding within our particular subjective experience, the ancients of india are further ahead than anyone.

If special relativity has taught us anything, it's that time is relative.

Oh, and gr too.

...it is clear that Earth's velocity does not, in fact, change...

Actually Earth's velocity is constantly changing. As velocity is a vector (in contrast to speed, a scalar) it has a directional component. Therefore, as the Earth follows a circular path its direction is always changing (albiet at a constant rate).

Therefore the directional component of velocity changes whilst the speed component remains constant. This implies a constant change in velocity.

Pedantic, I know... :)

I think that in our environment its more absolute and consistant
i loath time

I'm going to have to go against the grain on this one and instead argue that Time is in fact absolute.

I would like to start my arguement with the point that it is merely human perception of time that is relative, we are incapable of considering anything outside of our own perceptions and thus our theories are flawed by those perceptions. However time, logically, is and always will be something at once compleately insubstantial as it is both impossible to accurately define, yet at the same time the very fundamentals of the universe. I would also argue that the concept of space and time being linked is illogical despite 'mathematical and/or scientific' *proof* of such a link. Without matter time would still exist, it would be unnoticable but it would still exist, because time is not 'how long sometime takes' nor is it 'measurements between events' nor anything else, it merely *is*.

The bizaarly illogical concept that time/space are linked is, I think, stemming from the scientific obsession with closure, and thus all things need 'begginings' and 'ends' and 'measurable variables' etc. Sorry physicists out there but I'm afraid the universe is a whole lot more complicated then 'science' can account for, and 'science' itself is merely a stop gap measure when applied to the falsification principle.

Time is not affected in any way by our personal perceptions of it, or by anything else which may or may not occur. it is technically no more material then a concept, yet it is a concrete reality at the same time.

And yet our personal perceptions of time are highly variable and therefore relative due to the nature in which our brains process information and the way our bodies react to different situations.

So wait, you're talking branching timelines?

No.
I said it was difficult to explain.

If there is no possibility of interaction between two events A and B, i.e.their light cones do not intersect, then there is no meaning to the question "Did A happen before or after B" as there is no commonality by which to establish a measure of simultaneity. (This idea is in Hawking and probably Greene, but I have not read Greene so I can't promise on that one)

There are effectively two disconnected time sequences (not branching, that would connect them) and an event on one sequence can not be placed in the other sequence as there is no common reference.

Time has no existence apart from the human mind, as a concept, yet people point to a clock and its precise measurements and claim that the progression in consistent increments indicates an absolute.

Is time absolute?


What is this "time" concept of which you speak?

<snip>
To the one guy:

It has nothing to do with our instruments in gravity wells. In reality, time is, just as very much of the universe, a function of light. For instance, imagine you have a light clock (two reflective surfaces with a single photon bouncing between them with each bounce counting as a discrete "tick"). Since we know gravity can warp spacetime, this will effect the photon's path, effectivily making it vary directly with the strength of the gravitational field.

However, the speed of light (and thus a photon) is absolute in all reference frames, so this means that the ticks themselves slow, leading the slowing of time itself. The person in control of the experiment will not notice the slowing due to the fact that they are effected by it themselves. An outside observer, however, will notice this change.

I'm a girl, not a guy :P
The only actual live experiment I am aware of regarding time and gravity wells has been with the space program(s). When a shuttle returns to Earth, it's clock is typically faster than any clocks on the ground. How much is dependant on how long they remained in space. This can be explained through your method, or through mine. That's why it's a theory.

The facts remain a mystery, since we cannot alter gravity without travelling to space. Which also results in any "outside observers" being impossible, since gravity outside the vehicle would still be identical to gravity inside. Now, if such an experiment has been conducted on Earth (or in space), where gravity was altered inside a chamber, and not outside the chamber, with some sort of window for outside viewing. Then perhaps your theory would be more than just a theory. There is nothing available to prove either correct till such manipulation of gravitational forces is possible.

Actually, if you consider the principle of Ocham's Razor, mine would be more likely, because it is far more simple. However, that is admittedly no absolute judge of truth.

Another issue I have with your theory is the light clock. The speed of light is a constant, no doubt about that. However, there is one characteristic of any speed that is also a constant. Speed = Distance traveled over time (i.e. km/h, m/s, etc). If time itself is in question, then speed is no longer a useful measurement as it is dependant on time. If the light clock appears to slow due to a warping of gravity between the mirrors, that simply means there is a gravitational field between the mirrors that is altering the course of the light. Not that time has changed. Again, it's an issue with the instrument unless some experiment that can actually be witnessed by those outside of a gravity well in real time, without transmission or delay.

So basically, until we can create a gravitational field strong enough to theorhetically affect time as you suggest, it's going to remain a theory - just as mine will...

Actually Earth's velocity is constantly changing. As velocity is a vector (in contrast to speed, a scalar) it has a directional component. Therefore, as the Earth follows a circular path its direction is always changing (albiet at a constant rate).

Therefore the directional component of velocity changes whilst the speed component remains constant. This implies a constant change in velocity.

Pedantic, I know...

And you are right. Miswording on my part. I meant speed, in regards to how many rotations of the planet it takes for Earth to make one complete trip around the sun.

No.
I said it was difficult to explain.

If there is no possibility of interaction between two events A and B, i.e.their light cones do not intersect, then there is no meaning to the question "Did A happen before or after B" as there is no commonality by which to establish a measure of simultaneity. (This idea is in Hawking and probably Greene, but I have not read Greene so I can't promise on that one)

There are effectively two disconnected time sequences (not branching, that would connect them) and an event on one sequence can not be placed in the other sequence as there is no common reference.

Ah, that's basically what I was trying to say with branching timelines (bad choice of words, I know, but the best I could come up with).

This I agree with, but it is just basically the same as alternate universes having not real effect on each other, leading to space suffering from the same logic.

Time is self-consistent within the same universe. It is not within any other. Pretty much everything else suffers from the same.

Someone said earlier that "now" was the only absolute. Interestingly, "now" isn't even close to being such. Simultaneity, like the measurement of time, is a concept relative to the motion of the observers. There's a good example of why this is true in Greene's Elegant Universe, which is a must for anyone wanting to know more about this.
But "now" was qualified to be subjective for an individual consciousness. There, it is absolute.

Simultaneity, then, becomes what is meaningful coincidence for that individual.

My measurement, Mr. I-Still-Believe-in-an-Aether, will be different from yours if I am travelling through spacetime. Thou dost not know of what thou speakest.

Actually.... If you are both measuring yourself and the other, then you will come up with the same results, just opposite. hehe... well we are all making the assumption of constant velocity here.

Time has no existence apart from the human mind, as a concept, yet people point to a clock and its precise measurements and claim that the progression in consistent increments indicates an absolute.

Is time absolute?
Time exists, that much is irrefutable; examples from nature ... radioactive decay occurs at a set rate for all radioactive materials, change takes place in all biological systems, even black holes "evaporate," etc.

As to whether we "perceive" it to be relative or not, two examples:

1. You're placed in a totally bare room and told to wait. For you, time passes very slowly indeed.

2. You're sitting at your computer keyboard, deeply involved in a discussion in which you are intensely interested. For you, tame passes very quickly. ( I've often looked at my clock in amazement after sitting at the computer for what seemed to be only minutes, although the clock says that over four hours have passed! )

Ergo: time exists and may or may not be "relative," but the way we perceive it is most assuredly relative.

What's up with so many threads I comment in just dying? Do I offend? Can body odure somehow waft through the 'Net? WTF, over??? :(

In the case of this thread, I think it had reached its natural end. Certainly I had said what I had to say, and the same appears to be true of others here.

In the case of this thread, I think it had reached its natural end. Certainly I had said what I had to say, and the same appears to be true of others here.
Rats! Now you done went 'n spoilt my incipient paranoia! Tsk! ;)

Rats! Now you done went 'n spoilt my incipient paranoia! Tsk! ;)

In the case of other threads though . . .

That put him at ease a little, start next phase of the operation in two hours.


.

In the case of this thread, I think it had reached its natural end. Certainly I had said what I had to say, and the same appears to be true of others here.
I agree. I got what I came for, and a bonus.

Actually.... If you are both measuring yourself and the other, then you will come up with the same results, just opposite. hehe... well we are all making the assumption of constant velocity here.

gah, you know what I meant :rolleyes:

Time is absolute, its measure is relative. The same as distance, etc.

Does time even exist? Can anyone define time without resorting to human made measures? Vibrations on molecules or ticks on a clock? The question i think is whether time exists or not, not wether is relative or absolute :)

Time has no existence apart from the human mind, as a concept, yet people point to a clock and its precise measurements and claim that the progression in consistent increments indicates an absolute.

Is time absolute?

Obviously it is absolutely relative!

-Tom Steele

If it doesn't exist except in the mind, it is both relative and absolute, neither relative nor absolute, relative, or absolute, depending on what we choose to say it is. The question itself is ultimately meaningless.

When I was a little tidillywink, I thought that time was just a byproduct of chemical reactions in our brains. If we were cold blooded animals and the rates of these reactions varied depending on the external tempreture, then we'd think that hot days had more time, and that cold days had less time. This indeed could be what lizards think. But then I found out that radioactive materials decay at a rate independant of tempreture. This suggests that there is time seperate from the rates at which our brains function. There is no reason why we couldn't accept the dicotomy and talk of brain time and atom time. If we were cold blooded sentiant lizards, that might be what we'd do.

When I was a little tidillywink, I thought that time was just a byproduct of chemical reactions in our brains. If we were cold blooded animals and the rates of these reactions varied depending on the external tempreture, then we'd think that hot days had more time, and that cold days had less time. This indeed could be what lizards think. But then I found out that radioactive materials decay at a rate independant of tempreture. This suggests that there is time seperate from the rates at which our brains function. There is no reason why we couldn't accept the dicotomy and talk of brain time and atom time. If we were cold blooded sentiant lizards, that might be what we'd do.
Wow... lizards have deeper thoughts than I would have anticipated.

sensible things lizards... lieing around in the sun allday? sounds like they've got the right idea to me :D

Catbread']that was me (at least one of the people stating such). I'd just like to note that my views are on the nature of time are largely taken from indian/asian religious/philosophical texts in which concepts are often simply pragmatic tools with which to view the world in order to aid one in meditation/yoga.

the way i see it, physics is best/most qualified in attempting to define time "objectively" (which is dubious yet noble from the start, but i won't bother with the usual pomo BS) but as far as reaching an understanding within our particular subjective experience, the ancients of india are further ahead than anyone.


outstanding point i agree
btw i have been doing some interesting reading on the similarities between eastern spiritual science and western physics
- the quantum and the lotus, the tao of pyshics, and the dancing wu li masters are three good reads

as to whether time is relative or absolute
niether it is simply a construct, an illusion of the mind
i have no doubt that if we could percieve the fourth, and further dimensions then we would see how time does not exist
but unfortunately we can't,yet

and finally i really appreciate forums like this and thank you all for enriching me with your points of view