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Thread: Does Time exist?

  1. #1 Does Time exist? 
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    If I've missed a prior relevant thread about Time, I apologize in advance.

    There is, of course, a theoretical construct to explain the concept of time for life on this planet and within our solar system (if life exists anywhere else therein). Accepting that, though, does not provide sufficient proof that time actually exists. I have researched a number of online sources but nothing I've seen yet provides a definitive answer.

    However, is there a Cosmic Clock applicable to the entire Universe? Does anybody have a categorical proof that there is, in fact, a Cosmic Time? Perhaps the question is nonsensical? Perhaps there is no answer?


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    time is a concept


     

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    Moderator Moderator Markus Hanke's Avatar
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    Accepting that, though, does not provide sufficient proof that time actually exists.
    Yes, time exists. Together with space it forms the underlying structure of the 4-dimensional space-time the universe exists in.

    However, is there a Cosmic Clock applicable to the entire Universe?
    No. There is no absolute notion of time.
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    How do you measure movement speed or acceleration without time again?If nothing moved then there would be no time, for "as long" as everything stopped moving, but this 'how long' would not be measurable.
     

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    Yes, time exists. Together with space it forms the underlying structure of the 4-dimensional space-time the universe exists in.
    Thanks for the response, Markus. Space I can agree with; but do you have a link/resource that provides categorical proof that time actually exists?


    No. There is no absolute notion of time.
    Does not this second response contradict your first? If you believe that Time exists across all Space, does that not require an "absolute notion of time"? Otherwise, I don't quite understand your reasoning.
     

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    Brassica oleracea Strange's Avatar
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    Does Time exist?
    I'll tell you tomorrow.
    Without wishing to overstate my case, everything in the observable universe definitely has its origins in Northamptonshire -- Alan Moore
     

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    Thanks for your response, icewendigo.

    When the universe was 'young' - long before humanity could exist - and inflation was in progess, did Time exist? If so, please tell me why should it exist when it could not be measured (an apparent necessary condition according to your response)? However, if I accept, for the moment, your premise that Movement and Time must always be a binary and symbiotic pair, then by implication, you seem to support the idea that absolute Time exists, and without any need for humanity to observe it. If that is so, where is your proof? However, if I have totally misunderstood your position, please clarify.
     

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    Quote Originally Posted by Strange View Post
    Does Time exist?
    I'll tell you tomorrow.
    Aaah, Strange... great reply. I see we are on the same plane. Thanks.
     

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    Quote Originally Posted by fizzlooney View Post
    time is a concept
    THanks, fizzlooney.

    I thought I replied hours ago. Seems like it was lost in the void. However - Time is just an idea, huh? I can accept that.
     

  11. #10  
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    There seem to be two, no three, different things you are mixing up here. It is probably important to separate them out and understand each one:

    1. Does time exist?

    My answer is: obviously, duh! Which is not meant to be rude, but the fact that we are discussing the question at all and in an ordered series of responses requires time. One definition of time is that it is what keeps everything from happening at once.

    2. Is time only what we measure?

    I would say no.The universe has existed and been evolving for over 13 billion years. It didn't require anyone to measure the passing of time for that to happen.

    3. Is there absolute time?

    No. Relativity theory describes the relationship between time and space; neither are absolute but are related by relative states of motion and gravity.

    4. Are time and motion the same thing?

    A lot of people seem to think they are. Makes no more sense to me than saying that space and motion are the same thing.
    Without wishing to overstate my case, everything in the observable universe definitely has its origins in Northamptonshire -- Alan Moore
     

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    The reason you will find no definitive proof that time exists is because we do not, as of yet, have a theory of time.

    But time, as a dimension, only exists in exactly the same way that the 3 dimensions of space only exist.

    If time is the dimension that stops everything happening at once, then the spatial dimensions are that which stops everything happening in the same place.
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    Quote Originally Posted by mayapan1942 View Post
    but do you have a link/resource that provides categorical proof that time actually exists?
    Make an appointment at your local dentist. What do you need, and what do you get ? Right, an appointment date & time. Without it, no appointment is possible.
    Our universe is a collection not just of places, but of events. In order to uniquely specify an event you always need place & time, or else the event won't happen. You can't set up a meeting without giving a time, you can't talk about the earth without specifying a "when", because the earth 500 million years ago, or 50 years ago, or 5 minutes ago was a very different place then it is now. These are just examples. Time is indispensable in the universe. Every event in the universe needs exactly four coordinates, three of space and one of time.

    Does not this second response contradict your first?
    Not at all, because the emphasis was on "absolute". All observers measure time, but not all observers measure time in the same way. If you consider two clocks, one at the earth's surface, and one in a satellite in orbit, and compare the two, you will find that they do not run at the same rate. Compare a clock at rest to one moving very fast, and you will find that they do not agree. Time is a local measurement, there is no absolute time which is valid everywhere in the universe, but everywhere in the universe there is time. Mathematically, the proper time between two events (1) and (2) depends on the geometry of space-time between those events, and isn't absolute :

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    Time is a feeling. One two three four, you don't feel that? Next you'll say you can't feel rhythm. Yes, time exist, even without record. Its unfathomable how one comes up with the idea that time wouldn't exist. Don't you own a clock? A calendar? Do you see the concept that seconds and minutes are measures, of time, which will never stop.
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    Quote Originally Posted by kx000 View Post
    Time is a feeling.
    Thank you, kx000. That's an interesting idea and it could be true. It hadn't occurred to me. But, feelings can be so amorphous, so emphemeral, no?
     

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    Quote Originally Posted by mayapan1942 View Post
    But, feelings can be so amorphous, so emphemeral, no?
    They can only be ephemeral if time exists.
    Without wishing to overstate my case, everything in the observable universe definitely has its origins in Northamptonshire -- Alan Moore
     

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    Quote Originally Posted by Markus Hanke View Post

    Make an appointment at your local dentist. What do you need, and what do you get ? Right, an appointment date & time. Without it, no appointment is possible.
    I accept the need for a symbolic tool to help make sense of our local area. I accept the fact that it can be constructed (a second, a minute, an hour and so on) to satisfy those who need to measure, use and abide by it. Phenomenologically, that works. Numenologically - essentially - it's problematic. Put it this way: show me a second, don't show me a clock.


    Not at all, because the emphasis was on "absolute". All observers measure time, but not all observers measure time in the same way. If you consider two clocks, one at the earth's surface, and one in a satellite in orbit, and compare the two, you will find that they do not run at the same rate. Compare a clock at rest to one moving very fast, and you will find that they do not agree. Time is a local measurement, there is no absolute time which is valid everywhere in the universe, but everywhere in the universe there is time. Mathematically, the proper time between two events (1) and (2) depends on the geometry of space-time between those events, and isn't absolute :

    I'm no mathematician, but I can accept your reasoning within the symbolic construct, above, as far as it goes. I'm also aware of the "time dilation" effect as velocity increases. Both simply support the idea of time, not the fact.

    By the way, I really like the quote from Professor Hawking below which, I think, is quite germane to the discussion.
     

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    Thx, Strange. You've given me a few things to think about. I'll get back to you.
     

  19. #18  
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    Quote Originally Posted by mayapan1942 View Post
    Numenologically - essentially - it's problematic.
    I assume you mean noumenally. Perhaps you should get the moderators to move this to Philosophy (then I can give it the attention it deserves.)

    Put it this way: show me a second, don't show me a clock.
    That is just silly.

    Show me a story, don't show me a book. Show me an electron, don't show me the effects. Show me a vacuum, don't show me an empty vessel.
    Last edited by Strange; December 6th, 2012 at 06:12 PM. Reason: tact
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    Why do caesium 133 atoms always change between hyper fine levels of the ground state at the same rate? (We use that rate as the S.I. definition of a second)

    Why do photons always take the same number of changes bewteen the hyper fine levels of the ground state of a caesium 133 atom, to travel a given distance?

    This is what time means, and it has nothing to do with feelings, or us making sense of our local area. Caesium 133 atoms will always transition between hyper fine levels of the ground state at the same rate, regardless of whether there are humans around to measure it, or not.

    Regardless of how we measure time, we cannot deny that physical processes have a distinct duration.
     

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    Time is physically real.

    "It's easy to think of time as a concept or a mathematical construct, but not a physical reality. This is because time is utterly beyond sight. In fact, we can measure it, but only because we perceive it in some manner and used the word, 'Time' (Which we made up) to support a concept.
    We do not measure time as we do distance. We can see what distance is, but time? And then along comes Relativity and time is no longer a constant. I mean, if time was a constant, then we could say that we can always measure it consistently... but if it is not a constant, we cannot even trust our measurements." So the question; 'What is time?' is a good question.

    But it is a physically real constant and Relativity shows us this. Even if our measurement of it's "passing" can be distorted.
    After-all, light has similar property effects.

    Space-time is the word used to explain that. Time doesn't pass. We pass through it. It's constant, but our rate of motion is not constant. Changes in the variable - Motion- alters the end product for perceived time. Our measurement of time is a dependent variable.
    Last edited by Neverfly; December 6th, 2012 at 04:02 PM.
     

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    Quote Originally Posted by Neverfly View Post
    We can see what distance is, but time?
    No! We can only see the gaps between things. Show me distance, not a ruler!

    And then along comes Relativity and time is no longer a constant.
    As Einstein (supposedly) said: "Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute."
    Without wishing to overstate my case, everything in the observable universe definitely has its origins in Northamptonshire -- Alan Moore
     

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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by Neverfly View Post
    We can see what distance is, but time?
    No! We can only see the gaps between things. Show me distance, not a ruler!
    Exactly. That is what I meant when I said time exists as a dimension in exactly the same way as the 3 dimensions of space exist.
     

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    Quote Originally Posted by mayapan1942 View Post
    Put it this way: show me a second, don't show me a clock.
    Show me a meter, not a measuring stick. Can you do that ? I think not. Does that mean that space does not exist either ?

    I accept the need for a symbolic tool to help make sense of our local area.
    It is not just a tool. Without time, there is no local area. No events would ever take place.
    I am finding it very curious that you deny the existence of time. Obviously you aren't aware of the role time plays in physics.

    Both simply support the idea of time, not the fact.
    You can apply the integral to real world phenomena - let's take for example atmospheric muons. Those particles originate from the interaction between cosmic radiation and the earth's atmosphere. They are very massive, so they should decay long before they reach the earth's surface. Yet we detect them down here - why ? Because proper time is different for the muon than it is for the observer here on earth, leading to a prolonged life span of the particle. If you plug numbers into the integral you get just that result - that the muons reaches us.
    Do you think us detecting atmospheric muons here at the surface is just an idea, or is it empirical fact ?

    Time, in all its manifestations, is very real.
     

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    Quote Originally Posted by Strange View Post
    No! We can only see the gaps between things. Show me distance, not a ruler!
    (chuckle) going too far into this topic will lead us out of current known mainstream science.
    See, I'm one of those of the opinion that space-time is "something," not "nothing."
    "Nothing" is what exists outside of Space-time. Now, we cannot see outside of space-time, but we can see space-time itself. We can observe its properties at a rudimentary level. Which we do, even- Gravity. That is one of its properties.
    Another is Time.

    Speculation would be that outside of the Universe, this expanding space we live in, somehow, somewhere, outside of that, there would be no time, no distance between anything, or anything else at all.
    It's this difference that allows that gap you speak of, and the measurement of time and the expansion of distance, the Universe as we know it. It's how the Universe can expand, but not expand into anything. Because there is "Nothing" outside of it (of the sort of 'nothing' concept our brain finds utterly unfamiliar) but "something" within it.
    It may be quantum foam. Or maybe something else entirely. I don't know. No one here knows but it's being worked on...

    Either way, we do have Space-Time and if you stick mass in it, you end up with a distortion effect called gravity.

    If you move that mass through it, you end up with another distortion effect called time.
     

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    Quote Originally Posted by Neverfly View Post
    We do not measure time as we do distance.
    I disagree. Time is also just distance. It is distance between events, in a geometrical sense. If you look at the line integral in post 12 you will see that there is no difference whatsoever between measurements along the four fundamental coordinates. Time and space are on completely equal footing.
     

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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Neverfly View Post
    We do not measure time as we do distance.
    I disagree. Time is also just distance. It is distance between events, in a geometrical sense.
    True (As far as how we measure) and this is where the model of language will break down. Keep questioning anything I say.
    That paragraph you quoted from is a Layman's Perspective so that the reader can relate with, "yeah, I've had thoughts like that!" As they read on, they compare what's said against the perspective. Maybe I should edit that post to put that paragraph in quotation marks since two posters have now focused in on it... There was a reason I opened with the declaration that I did right before offering the comparative perspective...

    Edited it and added quotation marks.
     

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    Quote Originally Posted by Neverfly View Post
    Either way, we do have Space-Time and if you stick mass in it, you end up with a distortion effect called gravity.
    Agreed.

    Quote Originally Posted by Neverfly View Post
    If you move that mass through it, you end up with another distortion effect called time.
    It is already Space-Time. And nothing moves through Space-Time.

    Proper time always ticks at one second per second, and when in uniform motion you can always consider yourself to be at rest...
     

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    Quote Originally Posted by SpeedFreek View Post
    It is already Space-Time. And nothing moves through Space-Time.
    Proper time always ticks at one second per second, and when in uniform motion you can always consider yourself to be at rest...
    As long as not observing any other object in different uniform motion, relative to yourself...
     

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    Quote Originally Posted by Neverfly View Post
    Quote Originally Posted by SpeedFreek View Post
    Proper time always ticks at one second per second, and when in uniform motion you can always consider yourself to be at rest...
    As long as not observing any other object in different uniform motion, relative to yourself...
    It doesn't matter what you are observing, proper time always passes at 1 second per second. Your local caesium clock always ticks at the same speed.

    The same is true of proper time in the frame of the other object in different uniform motion, although you will find a difference in coordinate time for that other frame.
     

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    Quote Originally Posted by SpeedFreek View Post
    Quote Originally Posted by Neverfly View Post
    Quote Originally Posted by SpeedFreek View Post
    Proper time always ticks at one second per second, and when in uniform motion you can always consider yourself to be at rest...
    As long as not observing any other object in different uniform motion, relative to yourself...
    It doesn't matter what you are observing, proper time always passes at 1 second per second. Your local caesium clock always ticks at the same speed.

    The same is true of proper time in the frame of the other object in different uniform motion, although you will find a difference in coordinate time for that other frame.
    True, but...
    Help me out, here, Speedfreek- I have no idea what you're point is...
     

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    You can always consider yourself at rest, so how can time be caused by movement when there is no absolute motion?
     

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    Quote Originally Posted by SpeedFreek View Post
    You can always consider yourself at rest, so how can time be caused by movement when there is no absolute motion?
    Ok, I think I'm following you now. Motion doesn't need to be absolute to have effect.
    Motion is a variable; rate of motion (Velocity or speed) will effect time. Yes, proper time remains the same but that is only because proper time is relative to the observer in motion. To an outside observer, there is a difference in measured time.
     

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    Let's get back to basics.

    Two observers in relative uniform motion. Each can consider themselves to be at rest, and that it is the other that is moving. Each has a caesium clock that measures proper time in their own frame to be passing at 1 second per second, and each calculates coordinate time for the other to be dilated, by the same amount.

    The relationship between the two observers is symmetrical. Who is moving?
     

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    I disagree with this use as a paradox. Yes, an observer can consider himself to be "at rest" but observationally, that consideration is not necessarily true.
    For example, the Earth is at rest and the Sun is what is moving.

    In actuality, the Earth and the Sun are both in motion. All things, everything in the Universe, is in motion and we have no true frame of reference for motion and must use relative observation to gauge motion.
     

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    There is no paradox there.

    The point I am making here is that everyone is "at rest" in relation to time in as much as time always moves at the same pace, for everyone. This includes accelerating observers, or observers with different gravitational potentials.

    This is because time is a local concept, and you are always at rest in relation to it - your relationship with time never changes due to any motion you make. Your clock never changes speed and you will always measure a caesium 133 atom to change hyper fine levels at the same rate. Locally, light always travels ~300,000 km/s faster than you - because time never changes for you - time always moves inexorably on at a rate of 1 second per second. Your atomic clock that you carry with you always measures the correct time for you, whatever you do.

    If your relationship with time never changes, whatever motions you make, then how can time be caused by motion in any way?

    It doesn't matter how your time corresponds to anyone else's time. That makes no difference to how fast your beard grows, or how fast the caesium atoms "vibrate" in your clock.
     

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    Ummm... that's kind of what I said...

    I pointed out that the O.P.'s question is a good question.
    To the layman's perspective, he hears about time speeding up or slowing down in S.R. So, he thinks, time is not constant.
    I went on to point out this is not the case. Maybe I'm wording things very poorly, here.

    As to the rest, I disagree with you. We are not at rest even if we think we're at rest.
    Einstein knew this, and this is why the equations function as they do.
    Minkowski space - Wikipedia, the free encyclopedia
    This terminology comes from the use of Minkowski space in the theory of relativity. The set of all null vectors at an event of Minkowski space constitutes the light cone of that event. Note that all these notions are independent of the frame of reference. Given a timelike vector v, there is a worldline of constant velocity associated with it.
    I'm currently surrounded by loud distractions and cannot properly focus on going into depth but I'll be back after everyone's gone to bed or I settle the house with dynamite.
     

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    Quote Originally Posted by Neverfly View Post
    As to the rest, I disagree with you. We are not at rest even if we think we're at rest.
    I think what SpeedFreek meant was at rest in the temporal dimension. You can always move through space, but you cannot move through time.
     

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    Yes indeed.

    As Neverfly said, we are not at rest even if we think we are at rest. But my point is that whether we are at rest or not has no bearing on our relationship with time. We are always at rest in relation to time.

    So my question is, how can local time be caused by motion if motion has no bearing on local time?
     

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    What exactly is time?
    For an operational definition, it’s a correlation between events of interest to clock events.
    Letting ‘time’ mean ‘clock events’, time is a process of ordering events, with time always increasing or accumulating in a clock register, using traditional units of days, years, millennia, etc. or a subdivision of these units. One example would be recording two sets of data that relate to the same phenomenon. For meaningful results the times have to correspond between the sets.
    The light clock is simple in form, very precise, and universally consistent because light speed is constant and independent of its source. If we use a light clock to ‘time’ the speed of an object along a known distance x, what are we actually doing?
    We are simultaneously comparing the motion of an object to the motion of light by counting time (a number of ticks). The light motion is folded up inside the clock! The result is a ratio x/s = vt/ct = v/c. It should be obvious that the ticks serve to correlate the positions of the object with the positions of the light signal, for comparisons. In the case of constant motion, we only need use the end points of the paths. The entire experiment only involves a sequence of events in space and memory for data storage.
    If you are familiar with Minkowski space-time diagrams, notice the vertical scale is not 'time', it is ct, light path distance. You are now comparing apples to apples. The diagram is actually an historical plot of speed for a given object. Referring to Einsteins’ 1905 paper, in the definition of simultaneity, he defines the ‘time’ of an event as the position of the clock hand relative to the clock face. This is just another case of periodic motion, i.e. a number of ‘hand’ cycles. The number of cycles times the circumference of the hand path equals a distance, which can be converted to a portion of an earth orbit (year).
    Consider an event happening at Earth(x, y, z, t=2000). The t is a substitute for the motion of the sun for 2000 earth orbits. Once the sun completed one orbit of earth history within the galaxy, a new place value for ‘sorbits’ could be added to the ‘clock’ register.
    Time is an alias for distance!
    SR has shown subjective time to be variable, depending on the observers motion, thus eliminating a ‘one time serves all’.
    If there is an objective/physical time, such as a signal that synchronizes or orders processes in the universe, it hasn’t been discovered yet. (Such a thing could possibly explain entanglement.)
    I reject the poetic river/flow of time, moving through time, time travel, etc. (makes good scifi)
    Einstein formulated the invariant interval as X-ct = 0, an equality. (X is spatial interval)
    Minkowski mathematically manipulated ct via complex variables into the 4D expression.
    Some aren’t aware that all things mathematical are not realizable in reality, or don’t know the difference, and that theories are always models.
    The mass of the earth can be calculated as if it’s concentrated at the center of the earth. Would you volunteer to ride a space capsule that passes 3000 miles from earth center?
     

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    Thanks to all present for providing more for me to contemplate, although I cannot pretend to understand all of what I have read here.


    This much I do understand: time is a knotty topic (much more than I expected), and still very much debated, it seems. Perhaps the limits of language inhibit a full understanding of its nature and properties.


    Matter, space and motion (change) definitely exist – all three easily discernible, locally and at the cosmic scale.


    But, I don't have enough knowledge about various theories to help me to fully grasp (as much as I can) why time is a necessary cosmic condition. So, I have some reading to do.
     

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    Quote Originally Posted by SpeedFreek View Post
    Why do caesium 133 atoms always change between hyper fine levels of the ground state at the same rate? (We use that rate as the S.I. definition of a second)

    Why do photons always take the same number of changes bewteen the hyper fine levels of the ground state of a caesium 133 atom, to travel a given distance?

    This is what time means, and it has nothing to do with feelings, or us making sense of our local area. Caesium 133 atoms will always transition between hyper fine levels of the ground state at the same rate, regardless of whether there are humans around to measure it, or not.

    Regardless of how we measure time, we cannot deny that physical processes have a distinct duration.
    You can't feel time? Can't you feel rhythm? The harmony! The predictable chaos! Record is free of mankind, please do faith.
     

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    Sorry kx000, but I do not understand your meaning. Can you explain further?
     

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    Err... the laws of physics do not care who is good or evil, it treats them equally.

    Are you quite sure you are in the right forum? What is it you seek?
     

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    By moral, not to trade with any state.

    Any straight thinking man knows I can get booted, but they lose moral.

    Corporations. Key.

    To be born into a land, does not make me it. I am free of it. Your laws, I will not abide. I am my own. I know my hands. I know the moon shine. Yea.

    Sunray, native spirit. Me no chuck. Me man! Mr. President, would you follow? Some men you just can't reach, and to know who is who.
     

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    My nature is to help to educate people who ask scientific questions, and protect them from people who post nonsense.

    What has my nature got to do with the subject of time?
     

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    Quote Originally Posted by kx000 View Post
    By moral, not to trade with any state.

    Any straight thinking man knows I can get booted, but they lose moral.

    Corporations. Key.
    What on Earth are you talking about? What has any of this got to do with whether time exists?
     

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    Is time not simply the distance from one event to the next? Whether observed or not (unless you want to get into solipsism).

    I guess motion in a sense is time. But if that is the case then what about the old shooting arrow paradox? For those who are unfamiliar with this paradox it goes something like this.

    A man shoots an arrow from his bow towards a target.
    But before the arrow gets to the target it must get to the half way point of himself and the target.
    In order to get to the half way point however, it must get to the half way point of the halfway point and himself.
    And so on and so forth untill to you get to the point where the notion of motion is impossible, yet it still occurs everyday.

    Great topic btw
     

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    Quote Originally Posted by kx000 View Post
    By moral, not to trade with any state.

    Any straight thinking man knows I can get booted, but they lose moral.

    Corporations. Key.

    To be born into a land, does not make me it. I am free of it. Your laws, I will not abide. I am my own. I know my hands. I know the moon shine. Yea.

    Sunray, native spirit. Me no chuck. Me man! Mr. President, would you follow? Some men you just can't reach, and to know who is who.
    Knowledge91/KX000,
    Did you fall on your head, recently? Because you didn't used to talk this way. Are you thinking no one can use your words against you if they don't understand you, now, or what?
     

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    IMO, time is a result and is created during the process of unfolding reality.
     

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    Quote Originally Posted by Cerphres View Post
    Is time not simply the distance from one event to the next?
    Yes, precisely. You nailed it
    I had already explained that in posts 12 and 25.
     

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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Cerphres View Post
    Is time not simply the distance from one event to the next?
    Yes, precisely. You nailed it
    I had already explained that in posts 12 and 25.
    IMO, it is not quite that simple. Your statement assumes that the distance from one event to another already exists before the event has happened.
    It is my proposal that time is created "during" the unfolding event. A certain amount of time "is needed" for an event to become explicate (measurable), thus the time is "created as needed" by the event.

    Visualize a total condition of "quantum suspension" where no events take place. A total condition of stasis. Time would be absent from such a condition. Nothing to measure.
     

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    If time is the dimension that stops everything happening at once
    i have often seen this quote and it is wrong. i know John Wheeler said it, or something like it, but it is still wrong. and for the reasons given in this thread.

    "Time Is What Prevents Everything From Happening At Once.."

    The quote continues: "Space is what prevents everything from happening to me!"

    - John Wheeler (1911-2008)

    :-)
    Sometimes it is better not knowing than having an answer that may be wrong.
     

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    Quote Originally Posted by Chrispen Evan View Post
    If time is the dimension that stops everything happening at once
    i have often seen this quote and it is wrong. i know John Wheeler said it, or something like it, but it is still wrong. and for the reasons given in this thread.

    "Time Is What Prevents Everything From Happening At Once.."

    The quote continues: "Space is what prevents everything from happening to me!"

    - John Wheeler (1911-2008) :-)
    The expression is "everything happenening all at once (time) AND at the same place (coordinate)"
     

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    i mean it is wrong in the way that if time did not exist then nothing would happen not "everything happening at once".
    Sometimes it is better not knowing than having an answer that may be wrong.
     

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    Quote Originally Posted by Chrispen Evan View Post
    i mean it is wrong in the way that if time did not exist then nothing would happen not "everything happening at once".
    Ah, yes, I agree. But that does not answer the question of the BB, where apparently everything did happened at (almost) the same time and in the same place (expanding at FTL).
     

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    Quote Originally Posted by Chrispen Evan View Post
    i mean it is wrong in the way that if time did not exist then nothing would happen not "everything happening at once".
    Gave it another thought. If time did not exist then the first event would be "at once" and would be the beginning of time.
     

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    Quote Originally Posted by Write4U View Post
    Visualize a total condition of "quantum suspension" where no events take place. A total condition of stasis. Time would be absent from such a condition. Nothing to measure.
    That is not a physical scenario.

    Visualizing instead a (3+1)-dimensional manifold, on which I pick two points at random. I draw a curve between those points, then measure its length. That is what I call "proper time". In mathematical terms :



    This is what a clock will show that moves along that worldline I drew from point A to point B, and it is all which we can ever measure or define. All events are events in space-time; a particle at rest moves only through time, but not through space. A photon propagating at c moves only through space, but not through time. Everything else is in between. So long as we leave aside quantum effects there is little mystery in all this, to me anyway.
     

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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Write4U View Post
    Visualize a total condition of "quantum suspension" where no events take place. A total condition of stasis. Time would be absent from such a condition. Nothing to measure.
    That is not a physical scenario.

    Visualizing instead a (3+1)-dimensional manifold, on which I pick two points at random. I draw a curve between those points, then measure its length. That is what I call "proper time". In mathematical terms :



    This is what a clock will show that moves along that worldline I drew from point A to point B, and it is all which we can ever measure or define. All events are events in space-time; a particle at rest moves only through time, but not through space. A photon propagating at c moves only through space, but not through time. Everything else is in between. So long as we leave aside quantum effects there is little mystery in all this, to me anyway.
    You are absolutely right. My scenario is metaphysical.

    I see the "creation (fixing) of time" being somewhat similar to the "collapse of the wave function". I either case the fixing of coordinates produces an accompanying result.
     

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    Wasted enough time on this BS, bye
     

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    Change is the indicator that allows the measurement of time and if we were to say that time does not exist, we are saying that change doesn't either. Time would then be we call the period between one present to another.
     

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    I try tyo keep it very simple.
    Quantum argues for reality to manifest itself in discreet packets. This requires a change in spacetime coordinates. This change in S/T coordinates is restricted to SOL (hence to relationship between SOL and Passage of Time).
    Without quantum, reality simply does not become explicitly manifest. With quantum, time is used (created) at the moment of the event.

    In a condition of stasis time simply doesn't count.....
     

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    As many have pointed out in this thread - of course time itself as a physical quantity and a fourth dimension of the universe exists, every single equation in physics which involves time (or, more specifically, change in time) as a variable would not make any sense if time "didn't exist".

    However, indeed as Special Relativity thought experiments and real observations tell us, the notion of "absolute time" is (as far as we know) false - there is not an absolute universal inertial reference frame in which there is an absolute time, time is measured with respect to different frames of reference and the measured time change is dependent upon the velocity of the object(s) that the measurement clocks are on.

    For example, to a clock on a train moving at velocity v the change in time t_(train) that an observer would measure on this train during an interval t_(stat) measured by an observer whom is motionless will be:



    Thus, the time measured by the stationary (relative to the train) observer will be dilated by a factor of gamma when considering the time measured by the observer on the train.
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    Time cannot be separated from matter,owing to GR. We would agree that,before the miniscule universe time was not in existence...time only came into play at the begining of the miniscule universe.
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    Time does not become absolute since time is a function of a function such as T=(f)S(f)M. Where S is space and M is matter..so since the matter in the universe is not abosulte as in thesame distribution by mass in all directions, time T cannot be.
    "I am sorry for making this letter longer than usual.I actually lacked the time to make it shorter."###
     

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    Quote Originally Posted by fizzlooney View Post
    Wasted enough time on this BS, bye
    Since the rather meaningless statement "time is a concept" was your only post on this thread, I would tend to agree with you - you have indeed wasted your time.
     

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    Time is existent only in isolated areas as a concept. Outside of solar systems and galaxies there can be no time, only actions that unfold into results. Time is merely the measurement of these things.

    If the past has already been and is no more, how can it exist?
    If the future has not been, how can it exist?
    Therefore there is no time, only an instantaneous present that changes instantly.
    Last edited by Devon Keogh; January 2nd, 2013 at 01:48 PM.
     

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    I thought the ( past, present, future time ) is all one time, and is happening all at ones its only our perception that there is a passed, present and future time so we can understand what going on around us.
     

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    Quote Originally Posted by ANDY T View Post
    I thought the ( past, present, future time ) is all one time, and is happening all at ones its only our perception that there is a passed, present and future time so we can understand what going on around us.
    Maybe, but if that is true there is no known way to prove this, so I dont know.

    "If I have seen further it is by standing on the shoulders of giants."
    Sir Isaac Newton

    In my own opinion there is no greater mathematical Principle than that which is x - x = 0. This shows that matter can be created from nothing as long as the total product of the matter's mass & energy equal exactly zero.
    The only question is, "Where did all that antimatter go?"

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    Outside of solar systems and galaxies there can be no time
    Huh ? Why would that be ?
     

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    Quote Originally Posted by Markus Hanke View Post
    Outside of solar systems and galaxies there can be no time
    Huh ? Why would that be ?
    Well, as there is no sun, no days, no nights, and as time is a concept, it is absent from these areas.
    In these areas it is meerly the unfolding of events.

    "If I have seen further it is by standing on the shoulders of giants."
    Sir Isaac Newton

    In my own opinion there is no greater mathematical Principle than that which is x - x = 0. This shows that matter can be created from nothing as long as the total product of the matter's mass & energy equal exactly zero.
    The only question is, "Where did all that antimatter go?"

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    Well, as there is no sun, no days, no nights, and as time is a concept, it is absent from these areas.
    In these areas it is meerly the unfolding of events.
    we don't really measure time these days using the earth's rotational period or its orbital period. and anyway seeing as it is us doing the measuring we can use whatever system we like to measure time in other places in the universe as long as it is consistent.
    Sometimes it is better not knowing than having an answer that may be wrong.
     

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    Quote Originally Posted by Devon Keogh View Post
    Well, as there is no sun, no days, no nights, and as time is a concept, it is absent from these areas.
    In these areas it is meerly the unfolding of events.
    Surely time does not require day-and-night to exist. The notion seems almost primitive.

    Antarctica experiences long periods of constant darkness. Does time freeze during these recurring periods? Is it really that cold there?
    Dis muthufukka go hard. -Quote
     

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    Quote Originally Posted by epidecus View Post
    Quote Originally Posted by Devon Keogh View Post
    Well, as there is no sun, no days, no nights, and as time is a concept, it is absent from these areas.
    In these areas it is meerly the unfolding of events.
    Surely time does not require day-and-night to exist. The notion seems almost primitive.

    Antarctica experiences long periods of constant darkness. Does time freeze during these recurring periods? Is it really that cold there?
    Hmm, well there is time there, as it is taken from time zones. I was not meaning that it requires day and night, but it requires an object, like the sun, and events relating to the sun, to actually calculate time.

    "If I have seen further it is by standing on the shoulders of giants."
    Sir Isaac Newton

    In my own opinion there is no greater mathematical Principle than that which is x - x = 0. This shows that matter can be created from nothing as long as the total product of the matter's mass & energy equal exactly zero.
    The only question is, "Where did all that antimatter go?"

    Favourite Elements: Sodium, Neodymium, Xenon
     

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    We can use anything to measure time,as long as these things exist in the continum or has a world line...a consistent event is much better used.
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    Quote Originally Posted by Devon Keogh View Post
    I was not meaning that it requires day and night, but it requires an object, like the sun, and events relating to the sun
    Events such as... ?
    Dis muthufukka go hard. -Quote
     

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    Time:

    A second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

    If there is an atom outside of galaxies, there is time.
     

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    Quote Originally Posted by SpeedFreek View Post
    Time:

    A second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

    If there is an atom outside of galaxies, there is time.
    I mean viable and easy sources, an atomic clock is extremely expensive and cannot be viewed by the naked eye.

    PS: Events such as the changing tilt of the earth, creating seasons and the turning of the Earth, creating days.

    "If I have seen further it is by standing on the shoulders of giants."
    Sir Isaac Newton

    In my own opinion there is no greater mathematical Principle than that which is x - x = 0. This shows that matter can be created from nothing as long as the total product of the matter's mass & energy equal exactly zero.
    The only question is, "Where did all that antimatter go?"

    Favourite Elements: Sodium, Neodymium, Xenon
     

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    I no longer get the stand of this thread.i think the answer has long be given. This are just different form of asking same question.
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    Quote Originally Posted by Devon Keogh View Post
    Quote Originally Posted by SpeedFreek View Post
    Time:

    A second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

    If there is an atom outside of galaxies, there is time.
    I mean viable and easy sources, an atomic clock is extremely expensive and cannot be viewed by the naked eye.

    PS: Events such as the changing tilt of the earth, creating seasons and the turning of the Earth, creating days.
    It doesn't matter whether you own or use an atomic clock. Time does not have to be viewed by humans for it to exist.

    The fact that physical processes, like the transitions between the hyperfine levels of the ground state of a caesium 133 atom, always occur at the same rate, means that time exists.

    The universe is full of light. Light always moves at the same speed, in a vacuum.

    What is it that mediates the rate at which physical processes occur, such that they always occur at the same rate - speed of light, "vibrations" of atoms, radioactive decay times etc etc... what controls those rates so they all stay the same, relative to each other, in any given frame of reference?
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    Good Evening! The immitation of humaity has learned you to think there is time! There is distance there is pen to paper , Something goes by or does it! Are you you? Am i mE









    ?
    Quote Originally Posted by mayapan1942 View Post
    If I've missed a prior relevant thread about Time, I apologize in advance.

    There is, of course, a theoretical construct to explain the concept of time for life on this planet and within our solar system (if life exists anywhere else therein). Accepting that, though, does not provide sufficient proof that time actually exists. I have researched a number of online sources but nothing I've seen yet provides a definitive answer.

    However, is there a Cosmic Clock applicable to the entire Universe? Does anybody have a categorical proof that there is, in fact, a Cosmic Time? Perhaps the question is nonsensical? Perhaps there is no answer?
     

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    'i think therefore i am' a statement used to describe the philosophy of descartes...i support his view though.
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    Does time exist independent of mans perception of it? Is it just a concept of man? Of course there are different mainstream ideas about this. I prefer the idea that time is a man-conceived concept: that time is simply an interval of change measured by a clock.

    I like Eintein's related quote where he said:

    "When forced to summarize the general theory of relativity in one sentence:
    Time and space and gravitation have no separate existence from matter."

    I would go farther by suggesting that none of these entities would have any meaning to them at all in the total absence of matter and energy, and that they all can be defined or explained by relative conditions, locations, and changes of matter and energy.
    Last edited by forrest noble; January 4th, 2013 at 01:28 PM.
     

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    Quote Originally Posted by forrest noble View Post
    Does time exist independent of mans perception of it? Is it just a concept of man? Of course there are different mainstream idea about this. I prefer the idea that time is a man-conceived concept: that time is simply an interval of change measured by a clock.

    I like Eintein's related quote where he said:

    "When forced to summarize the general theory of relativity in one sentence:
    Time and space and gravitation have no separate existence from matter."

    I would go farther by suggesting that none of these entities would have any meaning to them at all in the total absence of matter and energy, and that they all can be defined or explained by relative conditions, locations, and changes of matter and energy.
    Conclusion, Time comes into existence with the expression of matter in reality.
     

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    Quote Originally Posted by Write4U View Post
    Quote Originally Posted by forrest noble View Post
    Does time exist independent of mans perception of it? Is it just a concept of man? Of course there are different mainstream idea about this. I prefer the idea that time is a man-conceived concept: that time is simply an interval of change measured by a clock.

    I like Eintein's related quote where he said:

    "When forced to summarize the general theory of relativity in one sentence:
    Time and space and gravitation have no separate existence from matter."

    I would go farther by suggesting that none of these entities would have any meaning to them at all in the total absence of matter and energy, and that they all can be defined or explained by relative conditions, locations, and changes of matter and energy.
    Conclusion, Time comes into existence with the expression of matter in reality.
    Sounds right to me
     

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    Therefore, time exists wherever there is matter or energy. Which is everywhere in the universe, in other words.
     

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    Time exist in whatever way,place or direction...the question i have had to be more complex and would require another thread...check 'Time' i will start the thread soon.
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    Quote Originally Posted by SpeedFreek View Post
    Therefore, time exists wherever there is matter or energy. Which is everywhere in the universe, in other words.
    I agree, but some theorists consider time as pre-existing matter, energy, and field. Some theorists define the universe to include hypothetical space beyond the bounds of matter and field. Some consider possibilities of the existence of other universes without matter, or energy, but which still would include time, gravity, and space and all the laws of physics. Probably none of these theorists would like my ideas either
    Last edited by forrest noble; January 6th, 2013 at 02:04 AM.
     

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    [QUOTE=Strange;373996]
    Quote Originally Posted by Neverfly View Post
    As Einstein (supposedly) said: "Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute."
    Following this reasoning we might postulate heat-dilation
    (if we put one hand in hot water ant the other in cold water, when we take out both hands one feels cold and the other warm)
    Quote Originally Posted by forrest noble View Post
    I like Eintein's related quote where he said:

    "When forced to summarize the general theory of relativity in one sentence:
    Time and space and gravitation have no separate existence from matter."
    .
    Quandoque bonus dormitat Homerus: even the great Albert nods off sometimes
    I hope you indulge my classical quotation, but even great scientists can say something stupid:
    In the first quote he is making psychology, mistaking a phenomen for its subjective, arbitrary perception
    In the second, is making ontology with semantics

    The very title of this thread is misleading, can we ask: does beauty, distance , left, liter etc...exist?

    Time is a concept man uses to communicate measurement, to measure change (as Leibniz said, or distance between events as Markus said). period.
    when can it be used (when does it come into existence)? when there is a change in the world.If the world were Parmenidean this concept is useless (does not exists)
    Matter does not make time exist (I am sorry for Einstein):
    1) imagine all the existing matter in one single block, we cannot invent, define or use the notion of time and neither gravitation.
    2) imagine the Earth with no motion or chemical reaction, there is no change. We cannot use the notion of time, and even if we did , we could not measure it
    3) imagine a world with motion and reactions but without growing enthropy, without the arrow of time, in which all re-actions be reversible : => Time does not exist :
    the past is equal to the future
    Last edited by whizkid; January 6th, 2013 at 05:29 AM.
     

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    Matter does not make time exist (I am sorry for Einstein):
    That is not what Einstein said anyway. What he said is "Time and Space and Gravitation have no separate existence from matter."
    You cannot separate those three concepts, they go hand-in-hand.

    1) imagine all the existing matter in one single block, we cannot invent, define or use the notion of time and neither gravitation.
    2) imagine the Earth with no motion or chemical reaction, there is no change. We cannot use the notion of time, and even if we did , we could not measure it
    3) imagine a world with motion and reactions but without growing enthropy, without the arrow of time, in which all re-actions be reversible : => Time does not exist :
    the past is equal to the future
    We are drifting away now from physics into the realm of philosophy. None of the above scenarios is physically relevant to our universe.
     

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    Quote Originally Posted by Markus Hanke View Post
    That is not what Einstein said anyway. What he said is "Time and Space and Gravitation have no separate existence from matter."
    You cannot separate those three concepts, they go hand-in-hand.
    ...
    ....We are drifting away now from physics into the realm of philosophy. None of the above scenarios is physically relevant to our universe.
    Markus, whenever you (or Einstein or anyone) use the word "existence", you have drifted away into the realm of philosophy (ontology),
    time, space, gravitation on one hand, and matter on the other, have different ontological status. Matter exists (phenomena, world), the other are words and concepts related to the world. What Einstein says is false: matter exists, space (and distance) has no separate existence from matter,
    the concept of time needs: matter that changes in an irreversible manner !!!

    Allow me to correct you, Markus, mine is not philosophy, it is science and logic:
    I was just explaining with clarifying examples why in this kind of world we may use the word "time" as an alias for change. If you cannot refute my examples (as I reckon), you must admit that time is a just a linguistic tool that can be used only when there is a change, and an irreversible one, to boot. If in any closed real (not philosophical) system, say, in a room etc.. you can reverse all the actions at your will, the notion of time, past and future vanishes. In order to refer to "time" you must needs refer to an external, irreversible change, like the progress of the Sun.

    Allow me, also, to correct you in your definition of time as "distance between events"
    Following Einstein, You are making an unlawful logical operation taking advantage of an idiomatic (i.e. improper) use of the word "distance", which is a concept related only to space.

    An event is a change in the state of the world (matter). A tower is standing now, tomorrow it crumbles down. This is "news", an "event"i.e. a change in one part of the world, but the ruined tower remains exactly in the same space as before, in a different state.

    Likewise , I might say that Marylin and lady Gaga are distant in beauty, linguistically. But I would make an unlawful logical operation ( a disconnect, in technical term) and a delirious scientific operation if I used the linguistic licence to conclude that beauty is assimilable to space and therefore postulate a four-dimention world with space-beauty
    Last edited by whizkid; January 6th, 2013 at 07:04 AM.
     

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    Quote Originally Posted by whizkid View Post
    Markus whenever you or Einstein or anyone use the word existence are in the realm of ontology.
    time, space, gravititation on one hand and matter on the other have different ontological status. Matter exists (phenomenon), the other are words and concepts.
    Clearly, this is philosophy. Not my area of expertise, so I couldn't comment.

    If you cannot refute my examples, you must admit that time is a just a linguistic tool that can be used only when there is a change, and an irreversible one, to boot. If in any closed real (not philosophical) system, say, in a room etc.. you can reverse all the actions at your will, the notion of time, past and future vanishes. In order to refer to "time" you must needs refer to an external, irreversible change.
    Well, in the real physical world things aren't reversible at will - you can crack an egg in your hypothetical room, but there is no known process of physics which will reassamble that egg into its original state. That was all I was trying to point out. There is no physical scenario in which the notion of time just vanishes.

    You are making an unlawful logical operation taking advantage of an idiomatic (i.e. improper) use of the word "distance", which is a concept related only to space.
    No, you are wrong. I am using distance as it is defined in differential geometry, i.e. via the metric of a pseudo-Riemannian manifold. Here the only difference between a spatial and a temporal dimension is its metric signature, and distance is equally exactly defined in time and space, and any combination of those. Refer here :

    Distance - Wikipedia, the free encyclopedia

    or any differential geometry textbook of your own choice.

    An event is a change in the state of the world (matter).
    No, I disagree. The car parked in front of my house has not changed since this morning. It was sitting there at 8am just as it is sitting there at 10am, not having been used or manipulated in any way. It is the exact same car. Does that mean time does not exist in the reference frame of the car, because nothing has changed ?

    But I would make an unlawful logical operation ( a disconnect, in technical term) and a delirious scientific operation if I used the linguistic licence to conclude that beauty is assimilable to space and therefore postulate a four-dimention world with space-beauty
    Beauty has nothing to do with physics, whereas the notion of distance is mathematically well defined. They are not comparable. Linguistics are just that - linguistics.
     

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    Quote Originally Posted by Markus Hanke View Post

    No, you are wrong. I am using distance as it is defined in differential geometry, i.e. via the metric of a pseudo-Riemannian manifold....r).
    Quoting geometry,or Einstein, doesn't help your cause if the definitions are obtained through illogical operations

    No, I disagree. The car parked in front of my house has not changed since this morning. It was sitting there at 8am just as it is sitting there at 10am, not having been used or manipulated in any way. It is the exact same car. Does that mean time does not exist in the reference frame of the car, because nothing has changed ?
    you are chasing your tail , you are referring to an external irreversible change : 8-10 o clock, i.e. the progress of the Sun
    if you want to discuss time you must forget the current conventions about time

    Beauty has nothing to do with physics, whereas the notion of distance is mathematically well defined. They are not comparable. Linguistics are just that - linguistics.
    You are right, distance is [math-]defined, but time is not. You are repeating the ingrained logical disconnect:
    time has the same ontological status of beauty, justice, democracy...: an abstract concept (and not a simple one, but) referring to a complex set of relations.
    If you want to state that it is physics, that it belongs to the realm of phenomena or maths, the onus probandi it's entirely upon you
    I would admire to see a proof
    Last edited by whizkid; January 6th, 2013 at 08:31 AM.
     

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    Quote Originally Posted by Markus Hanke View Post
    Time is a local measurement, there is no absolute time which is valid everywhere in the universe]
    Hi! I just want to make certain that you are saying that could we split the universe apart in pieces we would find the pieces to be of different age? Meaning that there is no definite age to the universe? The age of the universe is relative from where inside it the measure is taken?

    And isnt there some problem in proving negative facts? Like proving there is no god? How can it be proven there is no absolute time? By noting that if there IS an absolute time then the theory of relativity is not consistent? Is really the teory appliable everywhere? How is it applied within a point and how is it applied to the Universe as a whole?

    What IS meant by "absolute time" if not the aging of our universe?
    Isnt two events simultaneous if, and only if, the age of the universe was the same in the two events?

    EDIT: Because that is what anyone EXCEPT phycisians MEAN when they say that two events are simultaneous: Ask any layman if two events can be simultaneous if the universe is 15 billion years old in the one frame and being born in the other! No Sir! Something must be wrong somewhere!
    Last edited by sigurdV; January 6th, 2013 at 08:26 AM.
     

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    Quote Originally Posted by whizkid View Post
    Quoting geometry,or Einstein, doesn't help your cause if the definitions are obtained through illogical operations
    Look, I have given you my explanation of distance, which is in accordance with current scientific consensus. Whether you accept it or not is up to you.

    you are chasing your tail , you are referring to an external irreversible change : 8-10 o clock, i.e. the progress of the Sun
    if you want to discuss time you must forget the current conventions about time
    The clock readings are just labels; the car at 8am is not the same event as the car at 10am. They are two hours apart. Re-label it as you wish, but they are separate events in space-time. The labels are arbitrary, but not the distance between them.

    If you want to state that it is physics, that it belongs to the realm of phenomena or maths, the onus probandi it's entirely upon you
    You are getting this upside down rather badly; what I have explained to you is the current state of affairs in physics. Since it is yourself who appears to reject the concept of space-time the onus lies on you to provide the proof that mainstream science is in fact wrong, and that time cannot be treated geometrically. Primarily that will entail you explaining to us why gravity affects not just space but also time, since space-time does not exist according to you. More generally, you will need to proof the model of relativity wrong, as well quantum field theory, since all of these are based on space-time.
    Good luck with that.

    As for the status of the concept of space-time in physics, refer here :

    Spacetime - Wikipedia, the free encyclopedia

    as well as any differential geometry textbook of your choice.

    I would admire to see a proof
    Proof ? I don't have one. All I have is a mathematical model - General Relativity - which combines space and time into a continuum. GR also represents current scientific consensus on this matter, because once you talk numbers the model makes the correct predictions. It's that simple - it makes the correct predictions. Space-time also underlies other models, like quantum field theory, all of which comprise a large part of modern physics. That is what I represent. It is not perfect, and most certainly incomplete, but it is all we have at this point in time.

    You are entitled to your own opinions - reject it all if you wish. But if you do, please say so outright and don't waste my time trying to explain things to you which you already know you won't accept anyway.
     

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    Quote Originally Posted by sigurdV View Post
    Hi! I just want to make certain that you are saying that could we split the universe apart in pieces we would find the pieces to be of different age?
    Possible so. The "age of the universe" is based on co-moving coordinates, which are an idealization based on flat space-time in a perfectly homogeneous and isotropic universe. Of course we know that this is just an idealized model, one in which one can "slice up" the universe into hyperplanes with a common coordinate. In reality, the universe is not flat, there is curvature everywhere. A clock just next to a black hole would read a different age of the universe than a clock here on earth. The clock reading for every point depends on the entire history of that point in space-time. The best we can do is use an idealized value.
    The question is - how do you compare local values ? How do you compare the reading of a clock in some distant part of your universe to your own now ? What does "now" even mean in this context ? Or more generally - how do you decide whether all points in the universe see the same age or not at some given instant ? At the end of the day the very question is in itself meaningless, because there is no physical way to determine the answer.

    Isnt two events simultaneous if, and only if, the age of the universe was the same in the two events?
    No, because of the above.
    Quantime likes this.
     

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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by sigurdV View Post
    Hi! I just want to make certain that you are saying that could we split the universe apart in pieces we would find the pieces to be of different age?
    Possible so. The "age of the universe" is based on co-moving coordinates, which are an idealization based on flat space-time in a perfectly homogeneous and isotropic universe. Of course we know that this is just an idealized model, one in which one can "slice up" the universe into hyperplanes with a common coordinate. In reality, the universe is not flat, there is curvature everywhere. A clock just next to a black hole would read a different age of the universe than a clock here on earth. The clock reading for every point depends on the entire history of that point in space-time. The best we can do is use an idealized value.
    The question is - how do you compare local values ?
    The question rather is: Why should we?
    Local values is of no concern to the universe nor to its parts! Take the case of a photon.
    In its own local frame there is no passage of time...but it IS 15 billion years old when it hits my eye.


    Quote Originally Posted by Markus Hanke View Post

    How do you compare the reading of a clock in some distant part of your universe to your own now ? What does "now" even mean in this context ? Or more generally - how do you decide whether all points in the universe see the same age or not at some given instant ? At the end of the day the very question is in itself meaningless, because there is no physical way to determine the answer.
    Perhaps we are in agreement: The Theory of Relativity does not apply to minds nor to the universe as a whole so then:

    It does not claim that there is no determined age to the universe that can be equivalent to absolute time.
    Nor does it claim there is not a "now" that all minds within the universe experiences at the same universal time.

    To the Theory of Relativity the concepts "mind","universe" and "age of the universe" might be meaningless
    but that surely does not mean that minds and the universe does not exist nor that they have no age.
     

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    Quote Originally Posted by Markus Hanke View Post
    Look, I have given you my explanation of distance, which is in accordance with current scientific consensus. Whether you accept it or not is up to you.
    The clock readings are just labels; the car at 8am is not the same event as the car at 10am. They are two hours apart. Re-label it as you wish, but they are separate events in space-time. The labels are arbitrary, but not the distance between them....
    ...You are getting this upside down rather badly; what I have explained to you is the current state of affairs in physics. Since it is yourself who appears to reject the concept of space-time...Proof ? I don't have one. All I have is a mathematical model - General Relativity -
    You are entitled to your own opinions - reject it all if you wish. But if you do, please say so outright and don't waste my time trying to explain things to you which you already know you won't accept anyway.
    Your attitute is quite arrogant, Markus.

    - To begin with you are forgetting that the title of the thread is NOT GR, or spacetime, or Riemann geometry, or gravity, If you want to explain the current mainstream in physics, please continue the discussion (you dropped) in the other thread, there I am ready to take lessons from you, there you are really competent.

    - In the second place you are not able to distinguish between an opinion and a fact.
    The topic of this thread is if TIME exists, if you think id does, you must prove it with sound arguments, and not with what Einstein or Riemann said:
    I have already showed and proved that Einstein says something really stupid when he explains what is for him the relativity of TIME.

    If you (or your sources) cannot prove that times exists and is math-or-scientifically definable, then all your () theories crumble down.
    After you prove that time exists, you must prove that among its properties there is elasticity, that it is dilatable, and it is a dimension and that its dimension is assimilable to space.
    Only then you can state that you (or your sources) have a (consistent, plausible) matematical model.
    -----------------------------------------------

    the fact that that is the current idea, doesn't mean a thing: there was a time when the current idea was the phlogiston or the Tolemaic model.
    --------------------------------

    Now I'll tell you some facts, if you think they are opinions and that they are wrong you must disprove them with sound arguments and state what is your case.

    1) "Time" does not exist per se, ergo has no properties

    2) Time is a convention (like the parallels, the North, left and right.....)
    useful to communicate and coordinate our actions.
    If I want you to meet me I can say :"wait for me outside when I give you a ring" not using time, or more conveniently,
    "wait for me outside when the sun is 15° on the horizon" using the progress of the Sun (time) or "when it's 9a.m." using the progress of your watch which is based on the GMT signal which is based on the progress of the Sun. if your watch runs on a spring or a crystal or a caesium, makes no difference, you must set it according to the time signal.
    You use your clock to know the position of the Sun just as you look at a compass to know the position of the Lodestar, and coordinate your decisions

    3) being conventional, "time" cannot be absolute nor relative. (is equator, North, left... relative,absolute?it is what we decide) If you think differently, please give us an example of both.

    4) time is not a dimension, the concept of dimension belongs only to space.
    somewhere in current physics even mass is considered (improperly) a dimension but nobody would accept a space-mass 4-dimension, or "distance of mass"
    the concept of distance belongs only to space, as a figure of speech it is widely used for almost anything , I mentioned "distance in beauty" but we may add"in politics, tastes etc..", small wander we may talk of "distance in time" "distant events" etc.

    5) time cannot be dilated the same as beauty.
    the dilation can be only subjective or due to the physical process we chose as a our CHANGE of reference (the Sun cannot be slowed down , but my watch can)
    If one clock at C slows down it means only that "THAT clock has slowed down" , for some physical reason or other,
    the same as:
    if I have one chicken in the fridge and another in the freezer and the latter slows down I cannot conclude that time has been dilated.
    If I stated so I would have to prove it
     

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    Quote Originally Posted by sigurdV View Post
    The question rather is: Why should we?
    Local values is of no concern to the universe nor to its parts! Take the case of a photon.
    In its own local frame there is no passage of time...but it IS 15 billion years old when it hits my eye.
    I disagree. Time is always local - you measure time with clocks, and clocks are local. Of course you can have very many clocks glued together over some volume of space, but then there is no guarantee that they will all stay synchronised.
    Btw, a photon is not a valid frame of reference, and as for the 15 billion years...according to whose clock ?
     

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    To begin with you are forgetting that the title of the thread is NOT GR, or spacetime, or Riemann geometry, or gravity, If you want to explain the current mainstream in physics, please continue the discussion (you dropped) in the other thread, there I am ready to take lessons from you, there you are really competent.
    This thread is under Natural Sciences -> Physics, which is a mainstream section. If you wish to discuss time outside the framework of mainstream physics then I suggest you open a new thread in the appropriate section, e.g. Pseudoscience. While this thread is located here I will continue to treat it in the context of current scientific consensus; that is our frame of reference for all scientific discussions.

    and is math-or-scientifically definable
    I have already shown you the mathematical treatment of time in my last few posts. Why are you still asking for this ?
    Here it is again :

    Spacetime - Wikipedia, the free encyclopedia
    Distance - Wikipedia, the free encyclopedia
    Time in physics - Wikipedia, the free encyclopedia

    If you (or your sources) cannot prove that times exists
    You need exactly four coordinates to uniquely identify any event ( 3 spatial + 1 temporal coordinate ), thus time exists.

    wait for me outside when I give you a ring
    Outside - space
    When I give you a ring - time

    wait for me outside when the sun is 15° on the horizon
    See above

    when it's 9a.m.
    See above. All of these make reference to space and time. It is not possible to uniquely identify an event without reference to time. If time didn't exist it would not be needed to specify an event uniquely. That is not what we observe.

    time is not a dimension, the concept of dimension belongs only to space.
    Wrong. See links provided above.

    somewhere in current physics even mass is considered (improperly) a dimension
    No it isn't. Nowhere in accepted physics is mass considered a geometrical dimension like time. I don't know where you are getting those ideas from - do you even understand the geometrical concept of dimension as used in physics ?

    If one clock at C slows down it means only that "THAT clock has slowed down"
    Yes, that is exactly what time dilation means. Time is a local concept, measured by local clocks. A clock on the earth's surface is dilated as compared to a clock in a satellite in orbit, due to the gravitational potential of the earth. This effect is local, and directly measurable.

    If I stated so I would have to prove it
    The GPS considers this phenomenon - whithout compensating for time dilation it simply would not work. Other experimental evidence can be found here :

    Time dilation - Wikipedia, the free encyclopedia
     

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    Quote Originally Posted by whizkid View Post

    Your attitute is quite arrogant, Markus.
    I have already showed and proved that Einstein says something really stupid when he explains what is for him the relativity of TIME.
    Oh I say, well done!
    I must add that I am very surprised I have not already heard of this wonderful proof. Perhaps you haven't submitted it to any reputable scientific journals for verification or peer review.
    I agree with your use of the adjective "arrogant" but Markus is not the individual I would apply that description to.
     

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