Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Airthumbs on 04/05/2011 01:15:52
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Odd question I know! What I am asking is does Time have some kind of physical substance?
The "invisible forces", that at one time were thought to have no physical substance, Magnetism, Gravity, maybe Light at one point, have all been shown to have essentially physical properties, so where do we stand with Time?
It seems that Time being such a powerful force in our Universe should have some kind of physical properties. I keep hearing the words Space Time, and everyone seems to agree that one cannot exist without the other in our Universe.
Our best scientists have calculated that time can only move in one direction, so we know that time has momentum, but really what makes time? And a further leap through the loop would be; could time be the missing mass of our universe? [:o]
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Sweet question :)
Depends on how you see it I guess? Everything decays, and that it does depends on our arrow of time as I see it. But you can also define the arrow of time as 'decay' per se, I guess? We also have the definition of entropy where time too becomes a entropic process. Although I view 'time' as direction myself, with the direction expressing itself in decay, you can view the decay as 'time'. Still, I prefer the other way around as the idea of all different decays and decaying processes expressing itself differently makes it harder to define it. It's simpler if we use a common process for defining time like radiation. Then we have a form of artificial 'constant' from where to measure.
To me it seem irrelevant how you define it, bearing in mind that I know of no things, except light, that doesn't use clocks. And if you like, you can define light as using 'time' too, otherwise we wouldn't be able to define a speed to it. The only thing differing there being that light has no intrinsic 'clock' ticking.
So I believe in a arrow for it all, like a wave sweeping us constantly into a 'future'.
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Agree - nice q! Not sure about calling time a force - but then pre-newton gravity was considered as something that just 'was' rather than a quantifiable force. Also just because time has a direction I think it is logically incorrect to state that it must also have momentum. And I am not even convinced it "can only move in one direction" - more that any process which happens in time is overwhelmingly likely to be in one direction although it is possible to happen in the other
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Ok so Time has properties, it moves although has no momentum, all other things need Time to exist including light. It is measured, I believe, by the half life of elements in atomic clocks. Yet is it a wave? An arrow? Time must exist in quantifiable form otherwise it cannot exist at all?!
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These questions are so ontological that I am pretty sure they do not admit to a scientific answer.
Ok so Time has properties,
or is it that time is a property of other physical entities?
it moves although has no momentum
we only perceive entities through some form of interaction in time - but we have no proof nor argument that time moves , nor that it only moves in one direction
all other things need Time to exist including light
yet all the physics works just as well with time in reverse - and relies on that fact; invariance under time translation is a basis for conservation of energy
It is measured, I believe, by the half life of elements in atomic clocks.
frequency of radiation emitted by caesium 133
Yet is it a wave? An arrow? Time must exist in quantifiable form otherwise it cannot exist at all?!
must entities be quantifiable to exist. as a flippant example; the universe is finite/infinite and bounded/unbounded - all four combinations can be found in logically sound and serious arguments, that's an unquantifiable entity but I really hope it exists.
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These questions are so ontological that I am pretty sure they do not admit to a scientific answer.
That statement is a total contradiction. Rather then sticking to what we do know I am trying to push what we don't.
I would expect a similar response against someone trying to establish if the world was round or flat!
With regard to your other follow ups it appears that I am not the only one accused of Ontology. Is that such a bad thing? Give me an example of an entity that exists which is not quantifiable? The only reason that the Universe is unquantifiable is that we don't know how to quantify it. As a flippant example; the darkside of the moon cannot be seen from Earth but I really hope it exists..
I quite like this link by Feynman about confusion
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Ontology is the philosophical study of the nature of existence and being - it is not the scientific study. By no means am I suggesting that these questions are not worthy of being asked nor that we shouldn't seek answers; but the answers we get will, I believe, neither be falsifiable nor testable and thus not strictly scientific.
On your/my flippant examples
1. That's an existential question rather than a quantitative one!
2. All working and predictive theories of the moon included the back side of it, and we were not in doubt that there was a method that would allow us to gain empirical proof of that, ie go and look.
3. There is distinct doubt that we can ever know the size of the universe. The observable universe is measurable - but we can have no interaction in any way with the parts of the universe (if they exist) that are outside of our light cone. There is a more fundamental lack of knowledge.
Whether the earth is round or flat - I have seen experimental proofs of this and I have flown around the world - so no I don't accept these are similar questions. like the back side of the moon question this was a knowable unknown - some things do not seem to be amenable to the same logic, ie it is possible that they will never be known or knowable.
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With the greatest of respect don't most scientific theories fall under the title of Metaphysics which is a sub category of Ontology? I say this because they are just that, theories and someone had to do a certain amount of philosophical thought to get to them in the first place. Did Einstein have proof of his theories? Would Einstein himself not fall under the category of an Ontological scientist?
My theory is that Time has substance like everything else we see in our Universe. Although time is a mental creation we all fall under its influence and without it the Universe could not exist as we know it.....
Whether the earth is round or flat - I have seen experimental proofs of this and I have flown around the world - so no I don't accept these are similar questions. like the back side of the moon question this was a knowable unknown - some things do not seem to be amenable to the same logic, ie it is possible that they will never be known or knowable.
To say something might possibly be never known is a weak argument and to be honest comes across as an escape clause for the lack of current scientific understanding.
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With the greatest of respect don't most scientific theories fall under the title of Metaphysics which is a sub category of Ontology? I say this because they are just that, theories and someone had to do a certain amount of philosophical thought to get to them in the first place. Did Einstein have proof of his theories? Would Einstein himself not fall under the category of an Ontological scientist?
My theory is that Time has substance like everything else we see in our Universe. Although time is a mental creation we all fall under its influence and without it the Universe could not exist as we know it.....
Whether the earth is round or flat - I have seen experimental proofs of this and I have flown around the world - so no I don't accept these are similar questions. like the back side of the moon question this was a knowable unknown - some things do not seem to be amenable to the same logic, ie it is possible that they will never be known or knowable.
To say something might possibly be never known is a weak argument and to be honest comes across as an escape clause for the lack of current scientific understanding.
Einstein's theories are easily falsifiable and testable - the fact that your GPS works shows that so far we haven't found much wrong with them.
On the "unknowable" - on current theory we cannot communicate, observe or measure outside our light cone. In order to change this fact the fundamental assumptions of physics need to be overturned. This is not something that can get better through increased data or precision over the course of time. The position/momentum of a particle is similarly unknowable beyond a certain precision, time/energy etc. My original point took issue with your statement that a prerequisite of existence is the possibility of quantification; on both the very large scale and the very small there are counterexamples to this.
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On the "unknowable" - on current theory we cannot communicate, observe or measure outside our light cone. In order to change this fact the fundamental assumptions of physics need to be overturned. This is not something that can get better through increased data or precision over the course of time. The position/momentum of a particle is similarly unknowable beyond a certain precision, time/energy etc. My original point took issue with your statement that a prerequisite of existence is the possibility of quantification; on both the very large scale and the very small there are counterexamples to this.
You are absolutely correct, at present there are counterexamples of quantification yet to me this is because there are factors involved that are not yet understood. I appreciate that you are pointing out a weakness in my argument regarding the possibility of quantification yet I refuse to accept that Time is nothing.
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Oh, that depends on how you view it. Without the idea of time present nothing will exist. And that time has a temporal direction pointing to a 'future' is based on 'history'. Without a 'history' no experiments exist as they build on linear processes in a arrow of time. Even what we call entanglements crave a historic linearity to exist. But that the arrow is there doesn't state that it is everywhere. That's why I myself divide 'time' into two, or more depending, species. One being the macroscopic arrow, the other being just the idea of 'time'. To me 'time' as an idea may be very different from any arrow, and also different than any linear causality chain, in any 'direction'.
It's somewhat like gravity to me, existing everywhere we have a SpaceTime. Creating our world, and experiments. You need to see that all experiments we ever will do, must be created inside this arrow. That we afterwards define some phenomena as 'timeless' doesn't state that we've been 'out there' witnessing it.
To be able to do that would be a remarkable feat :)
Not possible.
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Odd question I know! What I am asking is does Time have some kind of physical substance?
The "invisible forces", that at one time were thought to have no physical substance, Magnetism, Gravity, maybe Light at one point, have all been shown to have essentially physical properties, so where do we stand with Time?
It seems that Time being such a powerful force in our Universe should have some kind of physical properties. I keep hearing the words Space Time, and everyone seems to agree that one cannot exist without the other in our Universe.
Our best scientists have calculated that time can only move in one direction, so we know that time has momentum, but really what makes time? And a further leap through the loop would be; could time be the missing mass of our universe? [:o]
The answer is yes, it's called light. The reason the speed of light in a vacuum is a constant is because it is the 'face' of the universal clock.[quote author=Airthumbs link=topic=39073.msg354486#msg354486 date=1304468152]
It seems that Time being such a powerful force in our Universe should have some kind of physical properties. I keep hearing the words Space Time, and everyone seems to agree that one cannot exist without the other in our Universe.
Our best scientists have calculated that time can only move in one direction, so we know that time has momentum, but really what makes time?
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The 'rate of flow of time' is the relationship between energy and matter in the universe. Unlike the arbitrary time we are familiar with it is variable.
I suppose I should qualify this by adding in my opinion (which just happens to be correct).
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A momentum is either something associated with a mass and a velocity, or as in light associated with a energy, as a photon has no mass. Then we have the use of momentum as a 'driving force', as when we speak about the 'momentum' of this thread for example.
But time has no mass, neither can we associate 'energy' to it. At least not in the usual way, you might assume that 'time' needs SpaceTime to exist. If so SpaceTime is defined as something existing in a equilibrium, never losing any 'energy', only transforming it from usable to unusable. That we can associate 'energy' with a photon becomes then 'self-clear' as it in its interaction transfer that 'energy' and when annihilated becomes unusable.
The same is not true for times arrow, or 'time'. Matter is indeed equivalent to energy, not the exact same, but equivalent in that you can transform matter into energy, and with a lot of effort, make at least a few short lived particles from radiation. To do that you need the arrow though, to observe it in.
So time, as far as I can see, has no momentum, if you don't mean it in the same manner as saying that this thread may be gaining a 'momentum'. But then we left the definitions used in physics.
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Oh, that depends on how you view it. Without the idea of time present nothing will exist. And that time has a temporal direction pointing to a 'future' is based on 'history'. Without a 'history' no experiments exist as they build on linear processes in a arrow of time. Even what we call entanglements crave a historic linearity to exist.
It seems you stating that for a quantum entanglement to occur Time must have memory?
The answer is yes, it's called light. The reason the speed of light in a vacuum is a constant is because it is the 'face' of the universal clock.
So is light an indicator of Time or are you indicating that light is Time?
The 'rate of flow of time' is the relationship between energy and matter in the universe. Unlike the arbitrary time we are familiar with it is variable.
I suppose I should qualify this by adding in my opinion (which just happens to be correct).
Thankyou for summarizing the 'rate of flow of time' in such a concise form. Is Time then just a word for the 'rate of flow of time' which is Time itself, or is Time itself something that has a flow? And if Light is Time then how can Time move faster then the speed of light?
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The same is not true for times arrow, or 'time'. Matter is indeed equivalent to energy, not the exact same, but equivalent in that you can transform matter into energy, and with a lot of effort, make at least a few short lived particles from radiation. To do that you need the arrow though, to observe it in.
yor_on, Is time really nothing then and just a thing introduced into equations to explain energy transfer from one state to the next?
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Now that's a interesting question. Does time have a memory?
How does time know which way to proceed?
You could argue that 'entropy' explains it as chemical processes having a orderly procession. But to do so you will have to assume that there is a hidden logic to to those processes that enable this 'causality chain' to exist in SpaceTime. And what would you call that hidden 'logic'? I don't know Airthumbs, but it was a really good question.
When I speak of everything having a history I use it in the way we see it. We see it as a causality chain, having certain property's. We expect things, like a chemical reaction, to act the same today as they did yesterday. We also use our memories (our history) combined with clever tools, as books and digital media, to collect the information we find into a knowledge base from where we can build further ideas and theories. Without our personal history nothing would change for us, no matter how much it would change for a observer having one, constantly getting his updated.
The causality chains doesn't hinge on our observations though, as I see it they hinge on 'times arrow', and for that one it won't matter if I'm there to observe it, or not. Or possibly, nothing can happen without an observer observing it? Still, the 'reality', as we know it, is that things change even when we're not there. But it's a tricky one indeed.
Maybe it's about 'energy transfers', but what allows them?
Time.
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It's actually even weirder, the causality chains we know macroscopically becomes probabilities in a quantum mechanical perspective. So what we grounded our science on, from ?? to Newton, without knowing it was sheer probability. Down there time gets strange qualities and seems to be able to go both backwards and forward as seen in particle conversions. But we don't see anything of that 'up here', and when we observe 'down there' we do it from the macroscopic arrow of time we have here.
If 'times arrow' loses its definition in QM then it seems a primary macroscopic phenomena. If it is so then using chemical processes as a way of defining 'the arrow of time' have a certain ring of truth to it. But it doesn't change the basics. If you see a causality chain there is needed a component gluing them together. And for that it won't matter which way you want to define the causality chain temporally. There is still a need for a glue.
There is one way more though. You could possibly assume that 'time' is a form of processes in itself. If you do so, then those might have different 'sizes' macroscopically as compared to quantum mechanically? It's just a weird idea I have though, but it would suit the idea of something being able to go two ways (QM) temporally. Don't really know how it would make sense, but if it was that way 'time' and its arrow is the same, but with 'size' being what force a direction. and as I see it those processes all being the result of interactions but depending on from what size we measure focused in a temporal direction. And that's a truly, very, weird idea :)
( To see how I mean you have to wave goodbye to the linear reality we see, to instead define 'reality' in 'chunks' temporally. That as 'interactions' combined with 'size' then would be the 'time' we measure. As I said, it's a weird, wild, idea. But it's so much that already is strange macroscopically, even though only shown at its extremes, so, why not? :)
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Oh, that depends on how you view it. Without the idea of time present nothing will exist. And that time has a temporal direction pointing to a 'future' is based on 'history'. Without a 'history' no experiments exist as they build on linear processes in a arrow of time. Even what we call entanglements crave a historic linearity to exist.
It seems you stating that for a quantum entanglement to occur Time must have memory?
The answer is yes, it's called light. The reason the speed of light in a vacuum is a constant is because it is the 'face' of the universal clock.
So is light an indicator of Time or are you indicating that light is Time?
The 'rate of flow of time' is the relationship between energy and matter in the universe. Unlike the arbitrary time we are familiar with it is variable.
I suppose I should qualify this by adding in my opinion (which just happens to be correct).
Thankyou for summarizing the 'rate of flow of time' in such a concise form. Is Time then just a word for the 'rate of flow of time' which is Time itself, or is Time itself something that has a flow? And if Light is Time then how can Time move faster then the speed of light?
So is light an indicator of Time or are you indicating that light is Time?
Li
The photon is the clock that the universe uses.
Our arbitrary time is based upon this.
Underlying this visible face of the clock is another but invisible clock.
Unlike a normal clock this one is variable in its going rate (rate of flow). It is time Jim but not as we know it. We don't notice the rate of flow changing as it is both a universal and local process and we are part of that.
And if Light is Time then how can Time move faster then the speed of light?
Because the speed of light in a vacuum under the influence of gravity is finite.
The rate of flow of time being the same as the speed of light can never exceed the speed of light.
If the universal mechanism that defines the rate of flow of time set that flow to be infinite then the speed of light would also be infinite but the speed of light would still be invariant. Note the word speed.
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I appreciate that you are pointing out a weakness in my argument regarding the possibility of quantification yet I refuse to accept that Time is nothing.
If it came across in my argument that I intended to show this - or believed it - then I was not clear. I am certain time exists, but I do not believe it to be quantifiable and definable in any extrinsic manner through use of other more fundamental concepts.
On your deeper ontological quest; I think it is almost a prerequisite (or at least must be approached in parallel) to similarly look at space and/or space time. I cannot think of an example of such a pair that are easier to define together - but I am sure that some exist.
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I see that someone else has posted a question similar to my line of thought. It regards the theory of a Multiverse. You see I think I finally understand the concept of Time. Without Time everything would just be in perpetual stasis and therefore our Universe would not exist. I extrapolated that from some of the responses above, but.......
I can't seem to get my head round the theory of a constant universal time. Not only that but why is so important to the nature of our universe to have a universal constant for time?
I note that people state that time and the speed of light in a vacuum are related, but not all of space is a vacuum. I am not talking about our individual perspective of Time but the actual Time universally. Does anyone know what actually causes Time, is it Entropy as mentioned in previous comments, chemical reactions?
I know that I can come across as confused at times but that's what this forum is for is it not? I blame it on sleep deprivation!!
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AirThumbs - to clear up one point. The reason we talk of speed of light in a vacuum is that this is the constant that emerges from maxwell's equations and it is this constancy that einstein based his work upon. the speed of light per se is not constant - it varies with the medium it is travelling in - this is what we see when we view something bent when it is semi-submerged in water, and why lenses work.
In any medium other than vacuum light propagates / interacts / repropagates - these interactions take time and the average speed is lowered. In the vacuum we just get the propagation and this is finite and constant.
Your comments on constant universal time - completely agree.
Entropy seems to make one direction of time overwhelmingly more likely than the other - but I don't think it makes time itself.
Be careful with sleep deprivation, too many years sleeping 3-4 hours a night you might end up dismantling the welfare state, impoverishing the miners, and launching a war over the falklands
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I can't seem to get my head round the theory of a constant universal time. Not only that but why is so important to the nature of our universe to have a universal constant for time?
, is it Entropy as mentioned in previous comments, chemical reactions?
There is no constant universal time. I believe the universe has an average rate of time made up of all the average local times.
Keep thinking about entropy.
Entropy seems to make one direction of time overwhelmingly more likely than the other - but I don't think it makes time itself.
I agree
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, is it Entropy as mentioned in previous comments, chemical reactions?
Keep thinking about entropy.
I meant to say entropy increases in a closed system, means that as energy (useful Energy) is used it becomes low grade energy of no use. When you boil a kettle it takes energy. The energy is still there after boiling the kettle but has dissipated and is of no further use. Entropy is not just chemical. Any process that uses energy produces entropy.
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Sorry, just noticed mistake in last post.
I meant to say entropy increases in a closed system, means that as energy (useful Energy) is used it becomes low grade energy of no use. When you boil a kettle it takes energy. The energy is still there after boiling the kettle but has dissipated and is of no further use. Entropy is not just chemical. Any process that uses energy produces entropy.
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Yes you can use 'entropy' as a description for any interaction reducing/transforming 'usable energy' into 'unusable'. that's why it's so popular as a rewrite of 'times arrow' too. But i don't expect it to be the arrow myself. That would be as defining the train as the 'motion', as I see it. You might have a motion, but it doesn't need to be a train doing it. Likewise you can have interactions pointing in one direction, changing from usable 'energy' to 'unusable'. but the reason they can do so is not some mystical process built in into their transformation, the reason they do it is the arrow, and that arrow can be described differently between frames of reference. that it can be described that way, and that a time dilation is a real effect, not just a 'illusion' points to that 'times arrow' have an existence on its own to me.
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Time only exists as a concept because man cannot perceive the future and the past only imperfectly. It is a deity-untrue but neccessary.