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So we have problems with clocks measureing time ?

  1. Jul 17, 2004 #1
    So we have problems with "clocks measureing time"?

    Well well, the big guys are beginning to think about the problems in their definition of time [i.e., to quote Gambini et. al.: "a fundamental limit exists on how accurate a clock can be" and "Every physicist notes, upon being introduced to quantum mechanics, that the role of the variable 't' is somewhat artificial! One is expected to believe the existence of a perfectly classical external clock to the system in observation and to treat time as a classical variable."

    If you read those articles carefully, you will comprehend that they are saying that "time" is an interaction parameter convenient to describing the phenomena being observed and not the reading on an "ideal clock" and that recognizing this fact leads to resolution of a disturbing paradox. Surprise surprise guys; it leads to a lot more if you look at it carefully.

    Maybe some of you "bright guys" will think about this a little more carefully in the future! You might learn something. I refer particularly to a few rather hasty posts by a number of physics forum minds: quotes are taken from the specified threads.

    I think you hit the nail on the head!
    Apparently no one could though it seems some of the big guys are lately at least beginning to comprehend the existence of a problem! I am afraid there is a lot more to it than they have yet seen!

    Well, it seems now that some of the big guys have found a reason to look a little closer though I doubt they comprehend the extent of the conundrum created by their failure to consider the limitations on their "definition of time".

    Sorry I will be out of the country for the next few weeks but I will look for any responses when I get back in town.

    Have fun -- Dick
  2. jcsd
  3. Jul 17, 2004 #2
    a perfect clock would need a motion element that is unchangable regardless of ANY relativistic effects, inertial gravity or otherwise.

    but where would you find such a creature that completely ignores the rest of the universe and does its own thing?

    and even if you DID find one, who's frame does the clock tell true time in? everyone will see a different rate still according to their frame <assuming Special Relativity with length contractions and time dialations still holds>
  4. Jul 18, 2004 #3
    Here are some interesting papers Dr. D:




  5. Jul 18, 2004 #4
    Clocks have nothing to do with time.

    Clocks have nothing to do with time.

    When clocks change as they leave the zero reference frame time continues at the same rate in the zero reference frame. Clocks change because they are not very good timekeepers. They change just because they are not compensated for the change of their environment. Just as poor timepieces do not compensate for temperature. Real time is absolute and it is the time from the Big Bang. If you had clocks even the poor ones we have today and they all started from the Big Bang and moved out with the expansion in all directions they would all tick at the same rate. All the clocks would tell the same time of, for example 22,255,356,574.0022001 light years.
    I have been developing an absolute clock.
  6. Jul 18, 2004 #5
    1. Since when has lightyears been a valid unit for the measuring of time ?? :uhh:

    2. You can't just say that your idea describes an absolute clock! Every clock mankind was so far able to develop is based on physical processes. We can't just assume that these procesesses are happening in identical ways under very different circumstances (which means different locations, speeds,...).
    I think that is the problem we are talking about here - that time-measuring has so often been equalled to time itself...

    3. If you say, the whole universe is an absolute clock, then it is surely hard to disagree with you. The problem is that there is no use in this "clock": sure, it exactly displays the time since the BigBang, but the only valid information we get by that is, that now is now - wow! To be useful for any physical application, we need at least some kind of unit, and I don't have a clue how to "scale" the dynamic change of the universe... (ideas welcome!)

    I haven't read the papers and articles linked above yet, so I might be repeating something already said there.

    I think, that time is not an entity by itself, such that it can be defined as a discreet dimension or something similar.
    The concept of time is something our mind needs to deal with the reality of
    change in the world sourrounding us.

    I hope you agree with me, that time is only useful when describing dynamic events. The concept of time can not be reasonably applied to a totally unchanging state (which is surely hard to find in reality - if not impossible).

    That doesn't mean that I think of time not being real - it is undoubtedly an unignoroable aspect of reality (as we perceive it at least...) and absolutely useful when describing physical events in a mathematical way.

    But still science has not brought us sufficient answers about the nature of time.

    I'd like to bring up a little philosphy here:

    Q: What would be (theoretically) the shortest useful period of time (which should then be the "smallest unit") ?

    A: (I think) The shortest period of time change can happen in.

    That brought me to two possibilities (and two problems!):

    1. There is no "minimum interval", which means change can happen in infinitely small periods of time. And that means we will never be able to calculate anything really accurately (which Heisenberg that said we can't anyway...)

    2. There is a physical limit to physical change. That would mean, there has to be a "shorter" interval, in which the universe is behaving totally static.
    That would give us the opportunity to define distinct points of time, but would still make it impossible to really measure time, because we cannot determine how long these "empty intervals" are... (no change - remember?)

    So I'm kind of stuck here :cry:

    If anyone can help me out: please do!

    P.S. this problem of the "shortest interval" is something Lama is dealing with from a mathematical point of view:
    (He started several threads, this is only one of them. If this one does not appeal to you, try another.)
    Last edited: Jul 18, 2004
  7. Jul 19, 2004 #6


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    Good luck with that. :rolleyes:
  8. Jul 19, 2004 #7
    Since the concept was created. Light years use units of space and time. If light years can be used as a valid unit of measuring space, then why should it not be equally valid as a unit for measuring time? In fact, it is. The star Sirius is 9 light years away. This tells us its distance in space. It also tells us its distance in time, when the light that we now see left the star.

    Everything changes all of the time (note the requirement of time). Nothing is static over time with respect to the universe.

    I am not sure of the value of this question. When you speak of change, I assume, and correct me if I am wrong, that you are refering to change in space. Using time as a measure of change in space is a very Newtonian concept. Time now has far more value than this, to me and to many others. Rather than using time as a measure of motion through space, time can also be used as a measure of interaction in space, as space-time. Here is where the major progress is being made, in my mind.

    Infinitely small periods of time doesn't really have any meaning to me. What is the applicability of such a concept? Anyway my watch keeps really accurate time. Or, am I misunderstanding what "really" means to you.

    The universe is not static. Change occurs at the speed of light. If it were possible to stop all light in the universe for an interval, then time would stop and you would have your static interval. I believe that this is not possible. Of course, it is possible to narrow the context, increasing simplicity and reducing accuracy and meaning, by which it is possible to assume, or pretend, that the universe is behaving completely statically.
  9. Jul 19, 2004 #8


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    The light-year is a unit of distance. It is absolutely not a unit of time, no matter how you'd like to argue it. The year is a unit of time. You are correct that for a universe that is not expanding, the time it takes light to travel x light-years is x years. Thus the distance and the time are numerically equal -- but they are not completely equal. One is a unit of distance, the other is a unit of time.

    Our universe is expanding. This expansion means that an object whose light took nine years to reach us is actually a little further than nine light-years away, because the universe has expanded during those nine years.

    - Warren
  10. Jul 19, 2004 #9
    Measurments of time

    In general terms a measurement between two points is distance.
    In trying to avoid the concept of explaining time in terms of time I tired to use general concept of measurment between two points, distance.

    If time is a dimension the same as any other spatial dimension then the measurement between points in the time dimension is a measurement of distance.

    If time started at the Big Bang and the dimension of transition from the Big Bang is the time dimension then time is the distance from the Big Bang to the current location of the universe.

    Your question about the smallest measurement of time.


    The Planck length is the scale at which classical ideas about gravity and space-time cease to be valid, and quantum effects dominate. This is the ‘quantum of length’, the smallest measurement of length with any meaning.

    And roughly equal to 1.6 x 10-35 m or about 10-20 times the size of a proton.

    The Planck time is the time it would take a photon travelling at the speed of light to across a distance equal to the Planck length. This is the ‘quantum of time’, the smallest measurement of time that has any meaning, and is equal to 10-43 seconds. No smaller division of time has any meaning. With in the framework of the laws of physics as we understand them today, we can say only that the universe came into existence when it already had an age of 10-43 seconds.

    Answered by: Dan Summons, Physics Undergrad Student, UOS, Souhampton

    You may make a clock that counts the number of Planck lengths that you pass through. The clock would than indicate the number of Planck lengths from the Big Bang until the present.
  11. Jul 19, 2004 #10
    No matter how I would like to argue it? I do not consider that thıs is a meanıngful offer. Your statement has nothing to do with how I might argue it, and everything to do with your reaction to how I argue it.

    All measurements of time involve measurements of motion through space. Our units of time are all dependent upon motion through space, and all units of motion through space are dependent upon units of time. For example, the unit of time of the solar year is based on the distance that the earth travels through space. To say that only one perspective is valid and that the other absolutely must be ignored is narrow sighted, in my opinion.

    The fact that the speed of light is typically considered only in terms of a measure of motion through space does not mean that it absolutely cannot be understood to have value in the necessarily symmetrical perspective of motion through time. In fact, the speed of light is often used for its time value, and not for its spatial value.

    However, I do not wish to argue with you on this, as you seem very absolute in your opinion.
  12. Jul 19, 2004 #11
    Hi Russell, nice to hear from you!

    Hi Russell,

    I shouldn't be on the internet as I have lots of details to get to today before I leave but I thought I would comment on your response. First, I think the articles you reference are fundamentally based on the time problem I am trying to get people to face but I know that the solution I have discovered is totally beyond their comprehension. Physicists have major problems with their concept of time and haven't yet recognized it.

    I do not believe Wheeler is the intellect Feynman was; at least not if he thinks Peter Lynds has solved Zeno's paradox. Now I didn't know Zeno personally but I believe (and there exist others who feel the same way) that Zeno's paradox has to do with the issue of continuity of time. The real central issue is that one can establish an infinite number of specific positions for the tortoise without including the end point.

    What is significant here is the infinity itself. And, Paul, if you do happen to read this, you should find that issue significant. What is important is that one [color="red']assumes[/color] (without any real defense) that the tortoise has passed through every moment between the start and the finish. It has to be an assumption as it cannot be verified. By the very definition of infinity, we cannot examine an infinite number of cases (no matter how many we examine, there is always another which must be looked at).

    The answer to the problems they see that all physicists presume is that time (on the infinitesimal level) is discontinuous; space (say, are we talking about the structure of the ether here????; -- just a joke guys) and time are kind of foamy on the infinitesimal level! It's the wrong answer guys! Our coordinate system is an abstract mental structure and is simply not bound by the necessity that it must exist in reality; it is bound only by the necessity that we can think of it. Nonetheless, there is a real problem here and I have the right answer and I can explain to anyone if anyone would take the care to listen (that is what I have been looking for, not praise and/or accolades but rather, just a patient student).

    Physics is supposedly an exact science. What that means is that every issue is presented in such a manner that the deductions can be expressed without possibility of error (presuming no mistakes are made): i.e., the extent and impact of the assumptions are also part of that deduction. The problem is that very few (if any; if one takes my experience into account) scientists take the trouble to establish the "exactness" of their statements.

    Think of the establishment of human knowledge as a monolithic structure. We have been working on that structure for thousands of years and the total is a vast building which would take a lifetime to even walk through. The major problem with scientific research is that anyone who knows enough to add seriously to the structure only knows the room he has been living in. The higher up one gets, the more difficult extending the structure becomes as every new piece requires the support of everything which has come from below.

    Everyone working way up in those ivory towers has total confidence in the foundations because he is aware of all struts in the floor below him which are required to keep the floor of interest to him stable. When he runs into a problem, he presumes it has to be with the support immediately below his work. It cannot be a misalignment of the basic foundation or that whole monolithic structure wouldn't be standing there as it does. Others would be having problems too. How do you think the deep thinkers of the dark ages came to discuss how many angels could dance on the head of a pin (yeah, I know it never happened but it's an allegory of things that did).

    When I got my Ph.D. I was quite dissatisfied with a lot of the beliefs I was expected to accept. Instead of working myself up to the higher floors (which is the goal of most all neophytes), I instead wanted to get a close look at the basement first. Most exact scientists would rather avoid thinking about it; they kind of leave that option to the philosophers as it is awful dark and forbidding down there. And, besides that, very respectable thinkers have been poking around down there for thousands of years without coming up with anything really useful up above.

    Well, maybe those who went to look had their minds on the wrong things. Maybe they are looking at the mortar between the stones instead of looking at exactly where the weight of the upper structure bares on those stones. In or order to do that one has to understand exactly what support is required and what support is not.

    Now, when I got down there, I discovered something very significant. Don't worry about it guys; it is significant whether you believe me or not. I have a lot of trouble trying to explain what I found because everyone wants to translate what I am saying into what [color="red"]they know is true[/color]. The problem is that there is a very fundamental difficulty with any such translation. What I am talking about cannot be translated into your picture of the universe unless that picture is totally without flaw (if your picture were without flaw, I guarantee it would be translatable and I can actually show that, believe it or not). On the other hand, everything you know to be true can be understood in terms of the picture I am trying to present if you would only take the time to look at that picture.

    The solution of the problem resides in an internally consistent interpretation of a number of concepts significant to understanding itself. Russell, I think we were well on the way to comprehension of those concepts when you chose to drop out of the discussion. I am very sorry you did that as I do not feel the ideas are beyond you.

    I will be back (hopefully) in about eighteen days. Between times I will have no contact with the internet to speak of. Think about what I have said and leave me a note. I will respond as seems reasonable.

    To the rest of you guys, I don't think you have any comprehension of what this whole brouhaha is all about. I suggest you think about it a little.

    Have fun -- Dick
  13. Jul 19, 2004 #12
    Reality can be described as the relationship between entities and process. The relationship between these two concepts can best be defined as opposing directions of time.

    The timeline for the entity goes from beginning to end, while the process goes the other direction, toward the next generation, away from, shedding the old. Think of a factory. The product goes from initiation to completion, but the future of the production process is in the direction of what is yet to be built. Life is the same way. The individual goes from birth to death, but the species is going toward the next generation, shedding the old like dead skin cells. Obviously this relationship works on all scales, as our body is processing those cells that constitute it. (Thoughts are the entities to the process of our mind.)

    Einstein said, "Time is what you measure with a clock." He also made the point that everything is relative, so from the relative perspective of the hands of the clock, everything else is going counterclockwise.

    Time is a measure of motion. Specifically that of the particular point of reference relative to its context. As context doesn't therefore include that particular point, it isn't an absolute, but is relative to that point, so is effectively moving in the opposite direction of that point. (Temperature is in fact another measure of motion; That of a general level of activity against a predetermined scale. As such, economic statistics constitute a temperature reading of the economy.)

    So while our subjective view of time is linear, as we follow the path through our context, objectively it is a process in the context of what is. Past and future do not physically exist because the energy to manifest them is what is the present. Just as a temperature of absolute zero would constitute motionless space, it would also lack any distinction of past and future activity.

    The reason this seems logical, but contradicts many common assumptions is because of the intellectual presumption that reality is a manifestation of the abstract, while in fact it is the abstract that is an approximation of reality. This confusion is because our point of reference are our own minds, to which abstraction is our understanding of reality.
  14. Jul 19, 2004 #13
    God, please go back to the hole you came out of!!! This is the most asinine response I can conceive of! Intellectual drivel!!

    Have fun -- Dick
  15. Jul 19, 2004 #14
    Expansion and the Time Dimension

    Expansion and the Time Dimension

    We see no evidence that the transition of the universe outward from the Big Bang is a transition in any spatial dimension. Observation indicates that there is no preferred spatial direction and that all distant objects appear to be moving away from us at a rate proportional to their distance, except for demonstrated local attraction. If the transition outward from the Big Bang was in any spatial direction observation of distant objects would indicate a difference in red shift in that direction.

    The evidence for the Big Bang, an expanding universe and the lack of influence on the spatial dimensions leaves us with the conclusion that the expansion outward from the Big Bang is occurring in an independent dimension.

    By observing a dimension that is independent from the spatial dimensions it is possible to extend our knowledge about the nature of dimensions.

    The spatial dimensions have only one degree of freedom of action. It is possible to move or transition in only one direction at a time, and any force applied from a direction different then the line of transition results in a change of direction equal to vector sums. Transition and the vector sums of transition are limited to the speed of light.

    There is a complete freedom of direction in the spatial dimensions. Any action of transition may be rotated through out any angle and to any desired degree of resolution.

    If the E dimension is an independent dimension then:

    The transition in the E dimension is totally independent of actions in the spatial dimensions.

    Total independence allows transitions in two or more directions at the same time.

    The transitions in independent dimensions do not vector sum to limit the maximum transition to the speed of light.

    There is no evidence that the maximum transition rate in each independent dimension is other than the speed of light.

    Just as in the spatial dimensions the E dimension has no preference of absolute direction. There is freedom of action through out any angle and to any degree of resolution. The universe is able to expand outward in all directions.

    It would appear that actions in the E dimension behave the same as actions in the spatial dimensions

    From the above observations it looks like there maybe dimensional constructs that have total independence from each other and within these independent dimensions there are limited independent dimensions.

    The question now is the E dimension the time dimension?
  16. Jul 19, 2004 #15
    You have made an interesting set of analogies. When you post some content, I will take a look at it.
  17. Jul 20, 2004 #16
    Define the term "understanding".


    "To grasp the nature, significance, or meaning of ".
  18. Jul 20, 2004 #17
    i think what DoctorDick is alluding to obliquely is reality is only relative if we choose to define it as such. we can define reality as absolute with the exact same degree of accuracy with no faults to the system. it's really just a mathmatical and mindset adjustment.
  19. Jul 20, 2004 #18
    Dr. D.
    Your bio mentions that you are retired. It has been my observation that the early stages of Alzhiemers are marked by easily provoked outbursts of temper. I hope you are just closeminded by nature.

    As to the Big Bang Theory;
    Three dimensions might define a volume of space, they are also a classic coordinate system, of which space does not come with. As the same space can be defined by any number of coordinate systems, then isn't space effectively infinitely dimensional? We all stand on the earth. That doesn't make it flat.

    As for geometry, it effectively begins with one, ie. the point. What would zero in geometry be? Empty space? While it might seem obvious that geometry defines space, it doesn't create it, I have on occasion got the impression that mathematicians think otherwise. Of course, throughout history people have thought of reality as a manifestation of the abstract, but as Stephen Wolfram, among others has been pointing out, the abstract is an approximation of reality. As our point of reference is the mind, which is an abstraction of reality, this confusion is understandable.

    Which leads me to Big Bang Theory. It occurred to me about fifteen years ago that if the expansion rate is inversely proportional to gravity, a cyclical process would explain this relationship very effectively. Not being a scientist, I don't have the intellect, time, connections or facilities to follow this very closely, but the reading that I have done suggests that it isn't a "slam dunk", though it is often portrayed as one.

    The original competing explanation was tired light theory, but I don't see how this would make any sense anyway. If light is encountering resistance, proceeding waves would encounter more than succeeding ones, so the effect would be a blueshift, wouldn't it? Wouldn't energized light make more sense? Sort of a rolling down hill effect, as amplitude decreases, some of this energy goes to expanding frequency, much like a cracking whip.

    Obviously I don't have enough of a grasp of optics, but we accept that gravity contracts space and this process is constantly radiating out the constituent energy, so why doesn't this radiation expand our measure of space? Matter contracts, energy expands?(These are also the two directions of time; Einsteins fourth dimension being gravitational collapse forming physical entities and definition. Expansion being the process that is continually forming new entities and definitions, absorbing the content of old ones. Hawking listed one of his directions of time as the expansion of the universe.)

    If space expands, but the universe does not, it would seem this energy would create a form of pressure that would potentially affect the gravitational process of galaxies, thus creating the additional speed of rotation currently assigned dark matter.

    Which leaves dark energy. Say we accept that light is actually the source of the cosmological constant. The further light travels across the universe, the more likely it is to pass through residual gravitational fields. We know that gravity creates a lensing effect that significantly magnifies this light to various different effects. What does it do to the light waves? Are they blueshifted? Would it be possible that this effect reduces the average redshift of the great majority of light waves from beyond a certain distance? Thus creating the impression that the rate of expansion is increasing.

    That the Cosmic Microwave Background Radiation is smooth at 2.7k could be a phase transition, at which this radiation starts to condense out as matter again.

    Maybe Black Holes are primarily the eye of a gravitational storm and the real activity is what we see, collapsing mass, radiating energy.

    Generally simple observations, but they seem logical to me, so I hope I haven't offended this august group too much.
  20. Jul 20, 2004 #19


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    If I understand DoctorDick correctly, then I think I begin to see the starting point of his perspective.

    Time is relative. OK, that makes sense. So a typical clock appears, as a practical expedient, to measure time. But it doesn't actually measure time, because time is relative to each object or particle. Just as location is. When we say that 2 objects are in the same place, we really only mean that they are approximately in the same place. Similarly, when we say use a clock, we are using something that provides an approximation. That makes sense to me too.

    So then, just as a tape measure does not actually measure the distance between 2 objects (since it addresses only 3 of 4 spacetime dimensions)... a clock does not actually measure time (since it addresses only 1 of 4 spacetime dimensions. That makes sense.

    And finally, I think DoctorDick is saying there is no such thing as a single time dimension shared by all objects anyway - any more than there is a single reference frame for spatial coordinates.

    Am I close?
  21. Jul 20, 2004 #20
    This is a difficult topic. Clocks do measure time, and such measurements are extremely useful, obviously. However, such measurements are useful within the context of motion through space.

    If we desire to move beyond Newtonian physics, then the concept of time must move beyond its use merely as a measure of motion through space.

    Time and space interact in space-time. Interaction of time with space is therefore the topic du jour, rather than simply the motion of space through time, which is what clocks measure.

    Consider two objects and a clock that they both observe. The clock provides a method for them to share an objective perception of time. However, in terms of the interaction of the space of object 1 with its time and the interaction of the space of object 2 with its time, the interaction of the space of the clock with its time is basically irrelevant to both.

    Clocks are useful for measuring motion of space through time. They are not nearly as useful for measuring the interaction of space with time.
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