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Time

  1. Jan 30, 2005 #1
    Knowing that time is just an aid for humans to understand progression, let us consider time to be progression here-just forward, backward, and idle movement.

    I just hit the letter "A" on my keyboard. It has already happened and is now in the past, yet i still vividly recall hitting the letter "A," what i was thinking as i typed it. Therefore, if i can think backwards in time is it not plausible to assume i could think forward in time?

    Zwei: How can i recall that i typed the letter "A" if it is no longer the instant in time where my finger was depressed upon the "A" key? I suppose i wrote onto my mind a memory, if this is the case my conclusion interests me: we live at a constant pace of writing memories into our minds so we have never lived in the present because by the time we could cognitively understand our experiences, they would already be written to our minds yet long gone a place in time.

    Drei: Is it not a fair assumption to make that the present does not exist; but instead our minds have the ability to go back in time and slightly into the future as is the case with pre-cognition. The present is a switching point between the future and the past, like a vertex. But a vertex is nothing but a compilation of two lines (future, past).
     
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  3. Jan 30, 2005 #2

    Les Sleeth

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    Yes, but there is a difference in quality. You can think backward in time knowing it actually happened. But if you think forward in time, you have to speculate about what might happen unless you want to assert the future is determined and that you can see it.


    That is correct, our perception of external events occurs after they happen since 1) info from an event takes time to reach our senses, and 2) our senses require time to convey information to consciousness.


    No, that is not a fair assumption. The present exists, but there is the "present" everywhere something exists. Let's say an event like a supernova takes place across the universe. When it occurs, it happens in the present. The light from that event takes 30,000 years to reach Earth. When it strikes my retina, I experience what happened in my present. The reception of information that originated from a past event doesn't change the fact that the light exists in the present when it reaches my eyes, or that what set that light in motion towards me happened in the present.

    Everything is in the present, and there is nothing but the present.
     
  4. Jan 31, 2005 #3
    My point exactly. But our minds are so slow that humans cant function on data perceived from the present in the present, thus we are confined to making decisions from the past. But if we cant think in the present, and the past doesnt exist, where is everyone.

    How to assign the present a value? .0000000001 seconds? There can never be proof that the present exists. You could not do anything, or make something that could measure the present. There is only speculation about what could happen, and memory of what has, but what "is" is an oxymoron. How could you disprove the possibility that every human being is living 50 minutes in the past and that there is that much of a substantial rift between the present and our ability to perceive it.?
     
  5. Jan 31, 2005 #4

    Les Sleeth

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    I think you are right, but I don't see the significance of it. So far, humans seem to do just fine being an instant behind the "external" present they are trying to deal with while tucked "inside" the brain. If the delay has no practical consesquences, why should we be concerned about it?

    Actually, I think it's pretty amazing the body works so well in this respect. We get information fast and accurately enough to work quite competently with the environment. I was just thinking about sports, where timing is crucial, and there you can see how some people really master the relationship between the external situation and their body movements.
     
  6. Jan 31, 2005 #5
    well if lizards have better reactions than do humans, they are living the future because they realize it is upon them faster than humans. As such, perhaps some advanced alien beings could outdo humans and lizards, how would you even communicate with such beings? :bugeye:

    My point is that whereas i used to not believe in time, now im sure it doesnt exist. Firstly it is an arbitray notion. Now, secondly, it is also different for differnet capacities of various brains. I state again, how could you know that any human action is not significantly off par from being a second old-60 seconds 60 hours-a decade?If no one can think in the present than how could you hope to measure celestial movements.
     
  7. Jan 31, 2005 #6

    Les Sleeth

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    I don't know if you are kidding or not, but I'll assume you are not. It seems to me you are confusing time with when some being receives information about an event that occurs. If that supernova I mentioned happens, and some alien lives on a planet closer to it than you, then he receives the light from that event before you. He experiences the reception of the information stemming from the supernova before you, but he is not in time ahead of you; you just find out about it later. And neither of you have anything to do with when the event itself actually happened.

    You are correct that a lizard capable of receiving info better than us through its senses could react before us, but again, that has absolutely nothing to do with the moment some event happens. That is not a "time" issue, it is a speed of processing issue.


    Time doesn't exist (IMO). Time is a concept we invented to measure the rate of change in the universe. But you are confusing how fast you receive information about that change with the rate of change itself.

    Regarding how far "off par" (i.e. after) our perception is from the actual event, why are you worrying about that? We already know that it is close enough for us to do everything from our jobs and athletics to calculating what was necessary for a trip to the moon and back. So I still can't see anything to be very concerned about there.
     
  8. Jan 31, 2005 #7
    if time doesnt exist how does one assign a rate of change in the universe? my point of the lizard and the human, they both live at the same instant but one is more conscious than the other of their spacetime-or has a more accurate feel for it. not sure how attuned to spacetime a lizard is, but my point is clear.

    in everyday life nothing is categorized by actual facts of time. time is nonexistant, people report news and make assumptions or observations all on the basis of how they perceived it in their time; i.e. the it takes them to process information. nothing we use to measure progression is accurate
     
  9. Jan 31, 2005 #8
    I would point out that in our universe there are only ones...one at a time, where time is the nothing ones are composed of. Time exist, but only by conceptual means.
     
  10. Feb 1, 2005 #9

    Les Sleeth

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    I meant that time, IMO, doesn't exist as a "thing," or entity or as a dimension as some believe. Like energy, I see it as a measurement of change except the way we measure that change is by monitoring regular cycles. Here's how I'd interpret it if asked (I know you didn't).

    Every instant all the universe undergoes change. It travels, it vibrates, and even space expands. The direction of all that change overall is from order toward disorder. Because of the entropic nature of change, most of us see time as how much "time" something is going to exist as we know it (like ourselves :eek: ); but rather than saying how much time, it might be more accurate to say how many changes something will undergo compared to something else which changes less entropically.

    To monitor the rate of change, we rely on situations that are cyclic and relatively constant (in relation to more rapidly deteriorating situations). Earth traveling around the sun is one reliable cycle we use, but an atom's oscillatory cycle is even more constant (a cesium atom-powered clock has an error of about one second in one million years.).

    So when I say time doesn't exist, I mean it isn't distinct from the physcialness of the universe; it is a change aspect of the universe. It is important to physics because calculations about any situation of the universe necessarily must involve change factors, factors which can be affected by what's going on in any particular frame of reference.


    True.


    But I am back to being unable to see the significance of that, mainly for one reason. Being a pragmatic sort of person, to me if something works, then why be concerned about it? In my every day life, I cannot tell if other attentive humans are receiving information faster or slower. Whatever the differences are, they seem too minute to be able to detect them. I admit it is sort of interesting to realize everyone may be becoming aware of reality at slightly different moments. Maybe that's what you've been trying to say.
     
  11. Feb 1, 2005 #10
    Les Sleeth wrote:

    I agree with this. Time as a dimension is just an abstraction, a result of observation and recording regular cycles, if I understand you correctly. (This corresponds to my concept 'recorded time'.)

    But you also have a real, phenomenal aspect of time -- as oldunion wrote:

    Without this kind of experiences it wouldn't be possible to notice any changes, so they are essential to the concept of time.

    But the special theory of relativity introduced a confusion here with its concept of spacetime; because, if space is real, then time also must have a real aspect as a dimension. But spacetime is a static concept with no definite present, and, because of that, it may seem necessary to regard the real experience of the present as an illusion. So here is a real dilemma - not only for oldunion - (which I have tried to start a discussion of in the thread "time as a self-reflective process" - as I think there is a solution).
     
  12. Feb 1, 2005 #11
    why?

    if space exists i relate it to water spilling; if you dump water it travels horizontally across a plane -but the plane was already there for it to travel across. If space is expanding, what is it expanding over/what is it transgressing? If your answer is nothing, then how could i ever agree with you that there is nothing beyond space. Do i walk from the edge of space into this nothing land, like i walk from the usa to mexico in two steps?

    without memory, time would stop for us because we would not be able to determine the rate of change or if there even was a change.
     
  13. Feb 1, 2005 #12

    Les Sleeth

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    Hmmmm. I'm not so sure about mixing time and experience that way. If time is a measure of the rate of change in the universe, then as a measurement method it obviously was invented by we humans and therefore must have a mental counterpart. However, what time is measuring (rate of change) is independent of our experience too; that is, the universe will keep on changing whether there is anyone present to experience/measure it or not. So I'd want to make a clear distinction between phenomenal change and the experience of change. Oldunion's memory of keystrokes, for instance, is a consciousness trait, not a change trait. And the key movement itself was a change thing and not a consciousness thing.

    I’d interpret at least some people’s confusion about time as due to a sort of solipsistic projection onto phenomenal reality. The universe is changing in a disintegrative way (overall), and there is nothing more to it than that. Quite ordinary. But for us, as an experience, change takes on "meaning" because change brings the gradual disappearance of our own existence. So the experience of time gets projected onto the universe because people see time as "something" with meaning. Some project their memory of the past or their ability to imagine the future onto reality as well, and dream they can travel in “time.” They might be able to do mental time travel but it doesn’t make any sense in the physical universe, which just plods along.


    Using the “rate of change” model of time, spacetime is also quite ordinary (even if relativistic effects aren't so ordinary). What is changing, or where we apply the time concept, is to the physical conditions of the universe. They require space within which to exist, and therefore to change. Time would not exist for purely empty and static space (if there were such a thing) because no change would take place. So spacetime is a way to describe the whole of any location (frame of reference) which must include the fact of change. It turns out that factors like movement and acceleration can affect measurement and change in a frame of reference; the twins paradox, for example, demonstrates that acceleration slows down the rate of change for the traveling twin. One can't describe a location (3D space) properly without also describing the change conditions (time) because it affects measurement. So spacetime is simply the holistic term for that inseparable relationship.
     
  14. Feb 1, 2005 #13
    oldunion (you made a slight mistake when posting the quotation, I wrote it, not Les Sleeth), I was referring to space as an aspect of spacetime. As this is a continuum, with time inseparable from it, time is as much a geometrical dimension as is the three dimensions of space. But I personally believe that this static concept of time is an abstraction, albeit a useful one. Of course, without memory time would stop for us, as you say.
     
  15. Feb 1, 2005 #14
    my mistake boherlin.

    i dont think i agree that space keeps expanding physically, nor do i agree that space is finite. i believe there are places where "you" could go that there is nothing physical, not your body and not an atom. A place where you would become imagination. nothing else makes sense to me.
     
  16. Feb 2, 2005 #15
    Les, I wrote:

    and you responded:

    I think we are using two different concepts of time here. I used the concept as it emerges on p. 3 in my proposed "alternative ontology" ( http://home.swipnet.se/bo_herlin/pdf/time_4pA4.pdf ) (I call it "active time" in the diagrams), and that is definitely different from your concept which I think correspond to my "recorded time", which is a result of the kind of measurements you describe, and a relevant concept in physics. Considering this, I think your objection is quite appropriate.
    If one accept both concepts of time as meaningful, it is also possible to "interpret at least some people's confusion about time" as a confusion of these concepts.

    There is, however, one aspect of my concept "active time" which I think you may find hard to accept, and that is that it concerns both time as a phenomenon directly experienced by ourselves and as an aspect of every entity in the universe, objectively perceived. But, because of the way the model is "constructed", I think the identification is appropriate.
    Of course, you must at first be open to the possibility that the model may say something of our existence. As a model of a two-dimensional world it is definitely possible, because it is, for instance, relatively easy to visualize how to make an animation of it in a computer. If I were a skilled animator I could have done it, now the diagram 5 on p. 1 in my pdf has to do the work - or your visual imagination when reading the "poem" on p. 3.

    BTW, when I'm writing this nobody has responded to my post "A still existing 'past' as a possibility" in the thread https://www.physicsforums.com/showthread.php?t=61890 . Maybe I have been to self assertive, and the label is provocative, but note that "past" is written within quotation marks. So I think a quite reasonable discussion would be possible. Tell me if you find me difficult for some reason. Any response would be highly appreciated, as I am new to this forum.
     
    Last edited: Feb 3, 2005
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