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Is TIME actually real? Is MOTION actually real?

  1. Dec 23, 2008 #1
    This seems like a strange question, but I don't know how to actually get out of it. If you don't actually THINK about this, you might just have a typical, incorrect kneejerk reaction. So it seems.

    First do Time...

    If you remember what you did yesterday, or last year, or 5 seconds ago -- when do you remember it? Now. You can ONLY remember the past right NOW. Tell me how to get out of that.

    If you worry about what you're going to do tomorrow, or you plan your vacation next month, when are you thinking about the future? Now. You can only think about the future right NOW.

    If you say, "I'm going to drop this ball, and it will actually fall." And then you do this 100 times or 1 million times and it always happens, any scientist will say that you are performing a repeatable scientific experiment. Really? When do you think about dropping the ball? Now. When are you dropping the ball? Now. When do you remember that you had dropped the ball? Now. When do you say, "I dropped this ball 50 times and it always fell"? You say this NOW. You can't get out of this!

    I don't think you can EVER get out of the FACT that you are always existing in the NOW, and everything else is just a thought process -- a strictly human function -- existing nowhere other than in the squishy neurons in your brain, which is trapped in the infinite NOW, and therefore any Before Now or After Now is just a human function, not anything that is actually a part of Reality. In Reality, there is ONLY EVER NOW, and there are these other things in your brain that have ridiculously tiny, ridiculously inaccurate slices of stuff, called memories or thoughts or projections or something, not really what is happening right now, here, in Reality.

    Now do Motion...

    If you throw a ball straight up in the air at 5 miles per hour, how fast does it hit your hand when it comes back down? Right, 5 mph. OK, now tell me, when it reached the top, what speed was it going? 0 mph? OK, now tell me, how long did it stay at that speed? How long was it traveling at a speed of 4 mph? 3? 3.000001? The answer usually given is an "infinitesimally" small period of time. Isn't that just a cop-out? Isn't that a scientists way of saying, "I dunno."

    So yes I took Calculus oh so many years ago. And we talked about "as the time change approaches zero" or whatever. This is a cop-out! So are cool mathematical formulas and charts and curves.

    What actually happens in Reality, in the real world, not on a piece of paper in some math formula, and not in your limited human brain matter? Tell me! How long does the ball stay at a speed of 0.00? I mean, in Reality! Not in some theoretical formula. Really. How long?

    Scientists seem to just give up and say, "Well, it is at an infinite number of speeds for infinitesimally small time periods." Right. Why don't you say God created the earth 5,000 years ago. That is about the same level of scientific thought! Does the answer actually make sense? Does it actually correspond to Reality? Or are those just some words that seem to "work" but don't actually make sense. (Exactly -- the Zero thing or the Bible thing, you can't tell!)

    So the question is, Is Time real? Or does it ONLY exist in the human mind? (and maybe the minds of a couple other earth-bound critters). How could YOU know, aren't you trapped in a mind, which is actually forever in the infinite now?? If time doesn't really exist, then motion doesn't really exist either! What is going on?

    Oh, and if you don't like the implications of this, then that is just another flaw of the human mind, a logical fallacy, called Appeal to Consequences. So if you say, "I can see my fingers moving" -- again, that is the brain matter, stuck in the NOW, being adjusted in some way so what is HERE, NOW always appears to be different. Is it? In Reality?
    Last edited: Dec 23, 2008
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  3. Dec 23, 2008 #2


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    I take it your the kind of guy who likes to live in the present. :biggrin:

    Time is a measurement system used to put events into a logical order.

    Even if we only exist in the present, events still do not happen all at once. An event in the past is not just in our mind as you seem to be asserting. One event could cause a present event, thus it must have actually happened. Time is a way to quantifying these logical sequences of events.
    Last edited: Dec 23, 2008
  4. Dec 23, 2008 #3

    Math Is Hard

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    Note: Moved from General Physics to Philosophy.
  5. Dec 23, 2008 #4
    "Even if we only exist in the present" -- when, exactly, are you NOT in the present? Therefore how do you know, exactly, that something else is not in the present?

    "An event in the past is not just in our mind" -- how do you know? Do you see the result of the event? When do you see it? Now. Do you remember the event? When do you remember it? Now.

    "thus it must have actually happened" -- but you only know this because of what you THINK you are perceiving, right NOW. Always Now. Only Now. There is no way out, there is nothing you know, ever, except what is, right HERE, right NOW.
  6. Dec 23, 2008 #5
    Of course from your reference frame, you are in the present :)
    An event from the past is also left as clues in other objects... like when you look at your hand on a wild party and find a wedding ring....
    And yes, welcome to the ummh.. now
    By the way the universe began in 1970. Anyone who says they are over 38 is lying about their age.
  7. Dec 23, 2008 #6

    Ivan Seeking

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    We NEVER observe anything in the present. We can only see that which occured in the past.
  8. Dec 24, 2008 #7
    Very true. Speed of light limit.
  9. Dec 24, 2008 #8


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    As to time (and space!), you're noticing the fact that observers only have 'direct' access to the here and now. There is a subtle problem that the notions of 'here' and 'now' are rather imprecisely defined, but this hasn't led to any scientific problems that I know of.

    I should point out that even if you go all the way to extreme solipsism where everything is just our minds imagination, the notion of time is still needed to describe what we're imagining.

    I hate using the word 'real' in these contexts, because it's notorious for being ill-defined. We cannot discuss a concept unless all agree on the concept being discussed!

    Your views on motion read more like someone not understanding their mathematics classes than someone doing philosophy.
  10. Dec 24, 2008 #9
    You do make a point...thing is that time exists, as G01 said, as a measurement system...the measured "distance" between one frame and another. The concept in its depth is much more arbitrary...so we don't really know. Time could really just be an illusion, much like many other concepts.
  11. Dec 24, 2008 #10
    I agree that "real" is an undefined word. Time and motion are function of consciousness, ie they are classical concepts. They are as "real" as anything else you consider real. If time is not real then space is not either, that's what Einstein believed and that's what i believe too. Take a photon for example - if it was emitted 5 billion years ago from Alpha Centauri and reached the Earth now, what time passed from its frame of reference? And what distance did it travel?
    Have a look at Bell's theorem and what it says about space and distance - Nature is non-local(i.e. there is no spatial separateness of objects in nature and we are all one wholeness). As Einstein said on the optical illusion of separateness:

    "A human being is a part of the whole called by us "the universe," a part limited in time and space. He experiences himself, his thoughts and feelings, as something separate from the rest - a kind of optical illusion of consciousness. This delusion is a kind of prison for us,restricting us to our personal desires and affection for a few persons nearest to us. Our task must be to free ourselves from this prison by widening the circle of understanding and compassion to embrace all living creatures and the whole of nature in its beauty."

    Even String Theory in all of it's 5 versions point to Space and Time being not fundamental:

    "This is a hint that perhaps spacetime geometry is not something fundamental in string theory, but something that emerges in the theory at large distance scales or weak coupling. This is an idea with enormous philosophical implications.".


    This says that all 5 versions point to the Holographic Principle, that the Universe is probably a giant hologram. It is my belief that the source of this hologram will be found to be consciousness.

    I'd say that the only thing we can dub "real" is consciousness(i don't mean consciousness as in the theory that electrical impulses in the brain are generating the notion of reality - I mean consciousness as that which is fundamental, transcendental and "foreign" to the human body and which allows elementary particles to be aware of themselves and see themselves). When you accept that consciousness is real and separate from the body, then the concepts of time, space and motion are not fundamental but a consequence of consciousness. As Einstein loved to say -

    "Reality is an illusion, albeit a persistent one"

    Couple that with the 1st law of thermodynamics and the zero-point energy universe and the picture will start to get clearer.

    I agree with Roger Penrose that the future Theory of Everything will have to account for consciousness. If not, it will be a theory of almost everything. I believe at the end of our quest for answers we will be finding - us.

    You don't have to be a solipsist to be inline with the findings of modern physics - IMO our collective consciousness is much more than that of a certain individual and I find solipsism somewhat frightening and ugly.
    Last edited: Dec 24, 2008
  12. Dec 24, 2008 #11


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    I agree. In this conversation I think the words "actually real" are more of a problem then "time" and "motion". This is a useless discussion until the OP defines "actually real".
  13. Dec 24, 2008 #12
    Good question!

    If a person "hears voices in their head" they are said to be delusional. They are said to be "mentally ill". They are said to be perceiving things that are not "actually real". And I think most of us "sane" people agree to all this.

    But, there actually is something going on in their head, right? THAT -- whatever it is -- actually does exists. THAT is really real. It could be some random firing of some neurons or whatever, but there is something that is "real" that is causing this condition in this person.

    But this thing that is real (misfiring neurons, in a human mind) causes that same human mind to "believe" that something is occurring in reality, that is actually not occurring in reality. This is the definition of Delusional -- a belief in something that isn't real.

    So the mental concepts of Time and Motion are the same thing.

    A "properly functioning" or "healthy" or "sane" human mind is always and without exception doing all of its perceiving or processing or remembering or thinking or planning or projecting -- all mental activities, right Here, right Now. But within that same brain is a "belief" that there is a "past" and a "future". But that brain is operating right HERE. And it is operating right NOW. And it always is.

    So the mental activity in a brain in the Here and Now causes a belief in that same brain in a Past and a Future, neither of which is Here nor is it Now. Well actually that isn't even true! The memories or mental activities are also right Here and right Now, where else could they be? So those "thoughts" or mental activities or beliefs ARE real, but that still doesn't mean that they correspond to reality, any more than the voices that a "mentally ill" person hears actually correspond to reality. What's the difference?

    So why are those mental concepts of Time and Motion, that do not correspond to Reality, "believed" to be true and are believed to be more "real" than some different concepts occurring in the brain of a person whose brain is causing them to believe they are hearing voices? They are both the same thing, concepts in the mind, that may or may not correspond to Reality.

    "But look, it's obvious, I can see motion, and I am not mentally ill, therefore motion must be real."

    Don't you see the trap you are in! You are trapped in a brain, that is filled with a mountain of memories and thoughts and projections and perceptions, and from this flows "beliefs", and you (that exact same brain) believe them. Where did the notion, "I'm going to move my hand now to prove that motion exists" come from? That same mind! Where did the memory of where you hand was, and the perception of where you hand currently is, come from? That same mind! Where is the belief that your hand will be somewhere else in the "future" -- that same mind! You are trapped in a mind, and that stuff, those beliefs, occurring in that mind do NOT necessarily correspond to reality. "But I know they do!" Same mind. "But I can ask other people and they say they know Time exists!" Still stuck in your mind. And presumably those other creatures out there you apparently perceive with that same mind you are always trapped in, are in an identical trap, with the same beliefs, all of which don't necessarily correspond to Reality.
    Last edited: Dec 24, 2008
  14. Dec 24, 2008 #13


    Staff: Mentor

    So then, is your definition of "actually real" something like "a thing is actually real if a sane person believes it is actually real"? If not, could you please try to be more explicit?

    If it is too difficult at this time to formulate a definition then try focusing your thoughts using one of the following:
    1) make a list of things and categorize them as "actually real" or "not actually real", then look for commonalities
    2) think of a test procedure that you could use to determine the "actually real"-ness of someting
    Last edited: Dec 24, 2008
  15. Dec 24, 2008 #14
    First tell me how you are no longer trapped inside of a human brain.

    You use words such as.......

    Formulate = in your brain.
    Definition = in that same brain.
    Focusing = in that brain.
    Thoughts = in that brain.
    Using = in that brain.
    Make a list = in that brain.
    Look = in that brain.
    Think = in that brain.
    "YOU" = in that brain.
    Determine = in that brain.

    How does a mentally ill person "know" something is "real"? Because it is in their brain.

    How do you Formulate or Define or Focus, etc, etc, etc? In your brain.

    Where is that whole concept of "you". In that same brain.

    Where did your notion that a test can prove reality come from? That same brain.
  16. Dec 24, 2008 #15
    Instead of defining "real" perhaps it will help to consider no matter what you or I or anyone thinks is real,
    it will hold no more significance when attributed to Now than when attributed to the past or future.

    Now does not exist in any more attainable or definable sense than the past or the future.
    All events, including those that are the synaptic events we call sensory perception, are chronologically prior to cognition or awareness. Even being aware that you are aware has this same chronology.
    So if time is to be expressed as something other than awareness, it is the order and rate of events of which you become aware. Time is then a condition of the physical events we call the universe, independent of anyone's awareness. The order and rate of such events are subjective and relative, both are conditions of awareness.
    Because all conscious recognition of events agree on the order and rate of events under specific conditions and agree that the order and rate differ by these conditions, time is the order and rate of events.
    As the firing of a synapse and all the EVENTS that comprise the awareness of a single event hold to the same conditions of order and rate of the event being observed, there is no NOW. There is only our reference to events of the past that we agree would have been NOW had we the ability to cease all events in the universe at that point and still be conscious to recognize it. But of course, the conscious awareness of that point requires the events of our brain to continue in the order and rate necessary to be aware.
    So the NOW that you assume is the point of awareness is always in the past.
    The quantity of time that the ball is neither moving up nor down is also a qualification of time that assumes there is a now. Just as there is no now, there is no "time" that the ball is not moving wrt you. If you threw the ball and I threw you at the same time, you would travel with the ball and claim it never moved. I think you would agree that such an observation does not prove the lack of motion of the ball indicates a continuous now just because you didn't observe any motion. Now consider any variation of this motion of you and the ball and you will see that other than your preference to say it stopped, there is no way to measure, prove or even consider it as stopping unless you stop time as well, and that as mentioned above aborts the whole idea.
  17. Dec 24, 2008 #16


    Staff: Mentor

    I completely agree that I am trapped in my own brain.

    So then is your definition of "actually real" that "nothing is actually real"? Or maybe "we cannot know what is actually real"?
    Last edited: Dec 24, 2008
  18. Dec 24, 2008 #17
    You asked -- How can I come up with a test and prove what Reality is?

    I asked -- Even if you came up with a way to test Reality, wouldn't the "you" doing the testing still be forever trapped in a human mind/brain thing? If so, then isn't that brain thing creating memories it calls the past? And more mental events it calls the future? Won't it be doing just this, Here, Now, when conducting the Reality tests it created to test Reality?

    It seems like this very bunch of thoughts could be seen as a meaningless mental exercise. But then again, it actually seems to be the most fundamental underlying assumption in ALL that we believe to be true, to be Reality, and if not understood, then perhaps we are all living a life of Delusion.

    HEY! I see you edited your question after I had already quoted it! So yes, your new question is THE question -- how can we, a limited human brain/mind thing -- ever actually know what is Reality??

    (I am trying to start a discussion here to see if I am out of my mind!! :) But I do actually have an answer that I have been studying...)

  19. Dec 24, 2008 #18


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    Sorry about that.

    Well, since your definition of "actually real" is that "we cannot know what is actually real" then, by definition we cannot know if time or motion are "actually real".

    That is certainly a safe definition, and it makes the conclusion perfectly clear and unambiguous. Of course, it renders the discussion rather uninteresting.
  20. Dec 24, 2008 #19
    There has got be a fundamental reality to this collective experience we call life. If nothing is real, what would account for the explicit order in this perceived "world"? I believe it is consciousness. Although totally unknown i'd say it is the essence of everything, everything in the known universe. I recommend "DMT - the spirit molecule" by Dr. Rick Strassman, where patients treated with DMT(also called the religious drug) reported OBE's(out of body experience). I had seen hundreds of similar accounts on the net, but at the time none of them seemed credible. Now my viewpoint has changed. In fact, i'd say that all fields of physics point into that direction - from QM, through Relativity to Cosmology with its mind-boggling metric expansion of space.
    Last edited: Dec 24, 2008
  21. Dec 24, 2008 #20
    If there is no time or motion then how are these thoughts created?
  22. Dec 24, 2008 #21

    Are you asking where the mental picture is created?
  23. Dec 24, 2008 #22
    I mean if there is neither time nor motion then there is nothing new and nothing can be created.
  24. Dec 25, 2008 #23
    Right, we're stuck in now. However, my conscious experience (which we call subjective reality), my now, suggests to me that I'm part of some contiguous something that encompasses all the objects of my experience. Our collective recorded experience (which we call objective reality, ie., what we deem actually real) suggests this also.

    Of course that encompassing something could be like The Matrix. But unless and until some Morpheus unplugs me and I take the red pill (or I'm, say, schizophrenic and I know that I'm schizophrenic, etc.), then I behave as if what seems to me to be reality actually is reality.

    Saying that we're stuck in now implies that the present has a different status or significance, that it refers to something different, than the past and future refer to. The ordinary usage of the word now associates it with our most recent past records and nearest future projections.

    No matter how one models objective reality, the word now refers to something different than the words past and future. Exactly what these different terms refer to depends on the model.

    Anyway, I agree with you that, regarding the ordinary language use of the word now, we can't get out of it -- at least not alive.

    Is what we call objective reality actually real? Compared to what?

    We can model time as an index of reality. Like a movie, a set of pictures, of reality. Time is the movie, not the objects depicted in the various frames of the movie. A time refers to one frame of the movie. We can order the frames by laying out the film from start to finish, left to right, and numbering each frame with a successive integer, left to right, starting with 1.

    An interesting feature of our movie is that all the pictures are unique. They're all different, and these differences, no matter how small, are referred to as motion.

    I'm not sure I understand your problem with timing how long something is moving at a certain velocity. Infinitessimals and infinities don't have any physical referents in nature except wrt mathematics. Planck's constant would seem to set a lower limit for observable differences between any two pictures of any movie of reality. To get Planck scale resolution your film would have to be moving at very close to the speed of light past the aperture (or some solid state analog of that process). You'd need a lot of film, or a lot of memory, to get even a second's worth of action, and if you played the movie at a normal frame rate, then you'd be watching it for a really long time. :smile:

    I'm not sure what the fps limits are regarding high speed photography, but I would guess that you can probably actually see a pretty good approximation of exactly how long a tossed ball is motionless wrt the ground using current technology.

    To summarize regarding your questions about the actual reality of time and motion, the answer is yes, time and motion are actually real -- because of how we use the terms, time and motion and actually and real.
  25. Dec 25, 2008 #24

    Yes, and Yes.

    But it is actually even deeper than that. (People really don't think about these things? Strange!)

    What you are saying is, for our sense of sight, we are "seeing" light from stuff that has occurred sometime in the past -- the amount of time it took the light to reach us.

    But it goes much deeper than that! First that light has to hit your eyeball, which does its thing (whatever that is) and turns those photons into electrical signals. Those electrical signals travel down your Central Nervous System somehow, and then end up somewhere in your brain. In your brain there is then probably sort of shuffling around or processing done, and then there is some other thing that happens to cause "you" to finally "perceive" those brain functions, which resulted from those electrical signals, which resulted from the eyeball, which resulted from whatever was emitting those photons. Somehow. So even more "time" goes by from when the light hits part of you (the eyeball) until the time you say, "I see".

    And when you stub your big toe? Some amount of time goes by until those signals get all the way to the brain, same with taste, etc. The ear is probably really slow, with its big clumsy mechanical gizmos translating motion into electrical signals.

    So yes, from the standard vantage point it appears as if the human brain is always perceiving things that have happened in the past.

    But here is an interesting question... what if you cut the Nerve from the eye to the brain? Do you still "see"? If you cut the nerve from the ear to the brain... do you still "hear"? Hearing is occurring, isn't it? Well, the mechanics are happening, the electrical signals are being transmitted to a nerve, but then they end. So the brain doesn't get the signal, but the ear still hears. Do YOU hear? Aren't you an animal that has a bunch of parts, including ears? So, aren't YOU hearing? Even if your brain doesn't get the signal?? But if you say that "YOU" are a human and a human is an amalgam of parts, and the ear is hearing, then YOU are doing the hearing! If you don't agree with that then you must think "YOU" are some function of a brain. If you are a brain, then where in the brain? Which part? What if one part is missing, or damaged, or undeveloped? Are you non-human? A lesser human? What is a human?? What are "you"??

    So really what you are doing is constantly becoming aware of sensory input. I guess that is called Perception. And this whole long process of getting sensory input into the brain takes "time" -- you could say. But what part of the brain is actually AWARE of that sensory input? Isn't it just some other part of the brain? But then the rest of the brain does its thing, including putting a time-stamp on it, and saying to itself, "This occurred after that" or whatever, and creating a "memory" (whatever that is, more brain function) of that sensory data. All of which is many, Many, MANY steps removed from the actual thing that actually "occurred" -- the sensory perception, which by the way is many times removed from the actual THING. Say you "see" a rock. There is a massive amount of difference between that ACTUAL rock, the reality of the rock, and that stuff that is happening in the moosh that is your brain.

    People really don't think about this stuff all day? Weird! :)
    Last edited: Dec 25, 2008
  26. Dec 25, 2008 #25


    Staff: Mentor

    What does any of that have to do with the "actually real"-ness of time or motion?

    Btw, I noticed that you still have not defined "actually real", you have just made an epistemological statement that nobody can know whether or not something is "actually real".
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