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      CommentAuthorkrista
    • CommentTimeJul 28th 2009
     (6466.1)
    I had to draw little diagrams on paper to wrap my head around why this might make sense:

    Time may be slowing down, which makes it seem as though it's speeding up

    Besides being an interesting read, it threw up subjective vs objective reality problems in my mind, and I wanted to ask all of you Clever Sciency Boffin types: even if this theory were accurate, is there anyway for us to prove it when our time-measuring instruments are being affected by the very thing we're trying to measure?

    I also love the 'insect in amber' imagery of this statement:
    "Then everything will be frozen, like a snapshot of one instant, forever,” Prof Senovilla told New Scientist magazine. “Our planet will be long gone by then.”
    • CommentAuthornleavitt
    • CommentTimeJul 28th 2009
     (6466.2)
    Maybe the actual 11-dimensional math makes sense, but their plain language xplanation doesn't. Speed is distance/time. It doesn't make any sense for time to have a speed, because time defines speed. To me, if you are going to treat time as another dimension, it isn't going to freeze "eventually", it's frozen now, we just happen to be viewing the position of all matter in three variable at each point on the time axis in sequence.
    • CommentAuthorFan
    • CommentTimeJul 28th 2009 edited
     (6466.3)
    > is there anyway for us to prove it when our time-measuring instruments are being affected by the very thing we're trying to measure

    I don't know but look at http://www.telegraph.co.uk/science/large-hadron-collider/3319218/Time-is-running-out---literally-says-scientist.html for another description: it mention very large (cosmology) and very small (the collider).

    A lot of theories (e.g. "shortest distance between two points is a straight line") are approximately correct, and correct enough on a normal everyday scale (when we're observing things which are not too big and not too small, not too hot and not too cold, not too fast, not too heavy) but the minuscule inaccuracy in the theory becomes more and more apparent as the scale is more extreme ... at which you point someone suggests a more sophisticated theory (e.g. "huge gravitational fields cause space to curve") which can eventually be tested by observing those extremes.

    In this case "our time-measuring instrument" seems to be the whole universe, and it's *because* the universe is being affected by something (doesn't in fact appear to be the way that current theory predicts it ought to be) that people are suggesting modified theories.

    The way it goes is:

    1) Observe some facts
    2) Invent a theory
    3) See whether the theory predicts the observed facts:
    a) If not, contradicted by fact so change the theory
    b) Or, if so, then imagine what other, as-yet-unobserved phenomena would be predicted by this theory and then create a new experiment to try to make (or not) these observations
  1.  (6466.4)
    I've never known much in the way of deep physics that does make sense in plain language. This is interesting though. I kind of reminds me of someone trying to convince people that the sun doesn't revolve around the earth, but it's the other way around. Even 100 years ago this theory would have seemed like madness.
    • CommentAuthorFan
    • CommentTimeJul 28th 2009 edited
     (6466.5)
    I've never heard of this particular theory before, but, let's see anyway if I can explain it /argue in favour of it.

    There's an "expanding universe" observation, which says that the universe appears to be getting bigger.

    They use techniques like http://en.wikipedia.org/wiki/Cosmic_distance_ladder to say how far away something is from us, and http://en.wikipedia.org/wiki/Red_shift to see how fast it's travelling away from us: so they know the distance and speed of everything.

    They discover that the universe isn't just expanding, it's accelerating: http://en.wikipedia.org/wiki/Accelerating_universe

    To say "it's accelerating" is another way of saying "things that are further away are travelling more quickly". Imagine dropping a sequence of cannon-balls off a sky-scraper: the ones which are further away, i.e. which you dropped earlier, and which are the older ones, are travelling more quickly than the recently-dropped ones: because/therefore they are accelerating.

    An equivalent way of saying that is that things which are nearer/newer are travelling more slowly. If newer and newer things travel more and more slowly, that's at least similar, isn't it, to saying that time is slowing down? Why are things accelerating (which we observe)? Maybe things aren't accelerating: maybe instead everything is travelling at the same speed, but newer things cover less distance in the same time, not because they're slower but because time itself is slower.
    • CommentAuthor/
    • CommentTimeJul 29th 2009
     (6466.6)
    Time is an imaginary idea. And that's why imagination affects it.
    • CommentAuthorKosmopolit
    • CommentTimeJul 29th 2009
     (6466.7)
    I wonder if this would explain the anomalously high rotational speed of some galaxies which is one of the main bits of evidence for the existence of dark matter?
  2.  (6466.8)
    Well, if this theory can provide a unique prediction that new observations could then seek to verify, it might be ground-breaking. If not, it's nothing more than a curious supposition.

    EDIT: @nleavitt
    You're right in your objection, but I think that's just poor wording on behalf of the article (what a surprise). What they probably mean to say is that this guy is theorising that the speed of light is changing, which makes more sense, since it's the constant which governs how time and space interact. If the speed of light approached 0, then time wouldn't advance.
    • CommentAuthorGlacialis
    • CommentTimeJul 29th 2009
     (6466.9)
    Plain text string theory and 11-dimension math (assuming M-theory, etc):

    http://www.superstringtheory.com/

    Great site. Has advanced (geared toward scientists) and basic (plain text) explanations.
    •  
      CommentAuthorSaturday
    • CommentTimeJul 29th 2009
     (6466.10)
    "If time has been slowing down, and clocks are now running more slowly than they did long ago, it would appear from our perspective as if things have been speeding up. Looking back over billions of years, galaxies would seem to be travelling away from each other faster and faster at various intervals since the Big Bang."
    This sounds pretty poorly constructed.

    It is in fact physically possible to See the effect of energy and speed through time dilation via the loss of timers on satellites when compared to clocks here on the ground, but thats where some of the flaws in the article present themselves. All perceptions of time come from a frame of reference. If the universe's rate of time was slowing down, in what frame of reference is it to?

    As all things tend towards entropy it is arguable that as speed of objects in the universe decreases we are in fact losing time, but it can never drop below the minimum, every particle will always have the zero point energy (a particle can never come to rest), so by that logic everything is approaching the same rate of time which will eventually become uniform between every particle in the universe.

    Maybe.
    I'm a little drunk.
    •  
      CommentAuthorPPJJ
    • CommentTimeJul 29th 2009
     (6466.11)
    I'm a little drunk.

    Good on ya!

    Here is something I found on the brain's perception of time, which is something that probably needs to be taken into account as well.

    http://timestranscript.canadaeast.com/opinion/article/727019
    •  
      CommentAuthorkrista
    • CommentTimeJul 29th 2009
     (6466.12)
    I understand the really basic concept as to why you might suggest this is what's happening: when you observe something that appears to 'speed up', it may in fact be that you are 'slowing down' in relation to it.

    Well, if this theory can provide a unique prediction that new observations could then seek to verify...


    See, that's what I was wondering about. I can't for the life of me imagine how this theory could be tested if the instruments used to test it are affected by the theory itself. It's the frame of reference thing @Saturday mentioned. Unless we can identify more supposedly 'objective' constants that also appear to be 'speeding up' ... Or perhaps this will alter our ideas about the subjectivity of time perception.
    Maybe I'm just being a big Subjectivist thicko.

    Thanks to everyone for the links, as well. I'm going to go have a big ol' nerd-out now.
    • CommentAuthorpurvision
    • CommentTimeJul 29th 2009
     (6466.13)
    I like the theory, to an extent. I've always been suspicious of the whole dark-energy/matter theory.

    My thought is that, as the universe expands essentially at the speed of light, more space is created in a given year than the year before, because the diameter of the universe is larger each year. So, if we got to a point where more space was being created than there was time to create it in, time would slow down.

    And dark-energy simply vanishes in a puff of logic.

    But the idea of all being frozen in spacial amber at the end of time just doesn't seem to ring true. This might be the one case where Zeno's Paradox is actually descriptive.
  3.  (6466.14)
    @krista
    Whilst what you say is true on one level, I'm sure we'll never actually directly measure a change in the speed of light for the reason you give, there's always the possibility that modelling the history of the universe in this manner may predict some unique behaviour (that current leading theories don't predict or can't explain adequately) that could then be searched for with normal instruments in a normal manner. Like seeing the shadow of a person who you can't see and calculating their height from its length and the angle of the sun, except way more complex and less obvious XD
    • CommentAuthorFan
    • CommentTimeJul 30th 2009
     (6466.15)
    Yes, you might ask th same question about space: "if space is curved by gravity how could we measure that, given that it would curve our rulers and measuring instruments?" That theory was proven by observing gravitational lensing.
  4.  (6466.16)
    There's really no way we could test this within our lifetimes, friends. Judging by the article, if this is occuring, it is occuring so slowly that we would not be able to measure it, really, until several generations down the road with our current scientific ability. However, in time, if people actually work with this, we could develope some way to measure it and then know more for certain.

    Also, on the subject of theories: In the scientific community, something cannot be labled a theory until it has suffiecient proof to support it. Until it has sufficient support, it is labled a hypothesis or a study. If they are calling this a theory in the scientific community, chances are it has more support than we know about it from that small wall of text.

    But, honestly? I definitely can't wrap my mind around this in the least bit. How an expanding universe could possibly slow the movement of time is completely beyond me.
    • CommentAuthorFan
    • CommentTimeJul 30th 2009
     (6466.17)
    > There's really no way we could test this within our lifetimes, friends

    Because the speed of light is finite, we look into the past. For example, if a star is 100 light-years away, then it takes 100 years for light to travel from that star to here, and so when we see that light we're looking at a 100-year-old image of the star (we're seeing the star as it existed 100 years ago).

    Similarly with other parts of the universe: when we look at the parts which are far away, we're seeing them as they existed a long time ago.

    So, at any moment we can see both recent (near) things and ancient (distant) things: and that might be enough to see how things (e.g. the rate of flow of time, perhaps) is changing.
  5.  (6466.18)
    I reckon that's true enough. But how could one look into the past, at a star that's so many light years away, and say "Hmmmm.... time is moving slower now then it was then"? I don't know how we can accurately measure the passage of time here and there, or now and then. Especially since the instruments we would use to measure this would be affected by the time change here, and it would take far too long to send an instrument there even if we could possibly recieve feedback in a speedy manner from a probe any amount of light years away.

    I'd like to see a more detailed write up of this theory, I think.
    • CommentAuthorVerissimus
    • CommentTimeJul 30th 2009
     (6466.19)
    First it was 23-dimensional strings, then scary dark energy, and now time grinds to a halt...Sounds a bit like the theories I used to have just before they put me away in the asylum...

    Physics seems so far removed from the understanding of simple people like me that I might as well go back to bringing sacrifice to the Celestial Gods...
  6.  (6466.20)
    @entropyemma
    But how could one look into the past, at a star that's so many light years away, and say "Hmmmm.... time is moving slower now then it was then"?

    We can't directly, but that's not stopped us before. A good example is the inflationary theory, which as far as I'm aware is still the leading expansion theory. We couldn't look back and directly observe the period of intense inflation that the model proposed, but we could carry the model forward in time, and see that it predicted very specific patterns in the Cosmic Microwave Background. We launched a satellite to make the observations (I think it was the WMAP, although I'm not certain) and found almost exactly the predicted patterns. Until new theories or new results contradict the model, it's our best guess.

    So we'd seek to prove or disprove this theory the way all science happens... observing, extrapolating, coming up with theories, modelling the theories, testing reality against the models. It all depends on what I mentioned before, if this theory can provide a unique prediction that new observations could then seek to verify.