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Universe May Be Running Out of Time

RenHoek writes "With heat death, the big crunch and quite a few other nasty ways in which the universe could see its demise, we can now add "running out of time" to the list. A team of scientists came up with a new theory that would solve the problem of the elusive dark energy that seems to be accelerating the expansion of the universe. They figure that the universe is not speeding up but we are, in relation to the outer regions of space, slowing down. Tests with the upcoming Large Hadron Collider will give more insight if we're going to end up frozen in time."

8 of 343 comments (clear)

  1. er...define 'constant'... by Quadraginta · · Score: 5, Insightful

    The problem with TFA is that it makes little logical sense. In what possible sense can time be "slowing down?" "Slowing down" is a statement that something is changing less per unit time. If you like, that dx/dt is negative.

    But how can you measure the "rate" at which time itself is changing? If "change in time" (dt) is going to go in the numerator, what will go in the denominator? Can't be dt, of course. So how do you define the "rate" at which time changes? I can't think of anything. It's like asking the price of money. "Price" means "how much you get per unit money." You can't ask how much money you get per unit money. (Note to nitpickers: the price of currency, e.g. the price of dollars in drachma, is not a valid counterexample.)

    I'm sure the physics makes sense, but the language in this news article does not. If anyone knows what the actual science is, I at least would be grateful for a better explanation than this news article provides. Anyone?

    1. Re:er...define 'constant'... by Anonymous Coward · · Score: 5, Insightful

      I can see where you're confused. Actually the price of money *is* a good analogy. How much does a dollar cost? Depends on what you compare it to. Could be x yen or y pounds. Experiments demonstrate that the speed of light is a constant, and since speed = distance/time, time and space must warp accordingly. So what goes in the numerator? Basically, your calculus ratio should be something like dt(here)/dt(there) where 'here' and 'there' are different points in space and/or different inertial frames. Hope this helps.

    2. Re:er...define 'constant'... by AstrumPreliator · · Score: 3, Insightful

      Part of the problem is we don't have the language, technically speaking, to describe such a phenomenon. Our species has always viewed time as a fixed quantity and our language definitely reflects this. That said I'll offer two possible ways of thinking about it. The second will probably be the more accurate...

      First, imagine time can be described in term of space, that is perhaps 1 second = 1 meter. Now as you move through just the time axis you take a measurement with a piece of string, say to about 0.5m, then you keep going down the time axis for a bit and you take another measurement with another piece of string to 0.5m again. Then you compare the string lengths, the second would be shorter if this theory were correct.

      Okay, that first one doesn't make a whole lot of sense so let's move on! Consider Spacetime as a 4-dimensional manifold. Now consider the metric on this space, at least the time portion of it, as tending to zero as t->infinity. That is the distance between points shrinks on the t-axis*.

      That may not be the best of explanations but hopefully that helps a bit. My second example is very colloquial, I'm not a physicist so this is just how I can picture it =P.

      *For an example of a Non-Euclidean Metric check out The Riemann Sphere.

  2. Re:Read the last line of the article first by Thought1 · · Score: 2, Insightful

    Physics always has been the domain of sci-fi authors. How do you think we got most of our current theories? (:

  3. Re:Can we stop it? by Psmylie · · Score: 3, Insightful

    Just don't be so worried about all these universe or world-ending disasters that you absentmindedly step out into traffic and get hit by a bus. Like any vague fear of the future, the tricky part is to live long enough for it to matter :)

    --

    psmylie's dictionary: Godzillion (noun) Any number large enough to destroy Tokyo

  4. Re:EXCELSIOR!! by pluther · · Score: 3, Insightful

    Hey! Someday he will save the world from immanent destruction and even you will say "Thank you Al Gore! You're super awesome!"

    Nah, that's the funny part of it. He can only actually get recognition if he fails.

    If the environmentalists are successful, then nothing will happen.

    It's like the Y2K bug: All those people working to ensure that nothing happens. So when in Y2K, nothing happened, the general response was "huh, guess there never was a problem after all."

    --
    If the masses can keep you down, you're not the Ubermensch.
  5. Re:Read the last line of the article first by Bill,+Shooter+of+Bul · · Score: 2, Insightful

    Not exactly. There a a billion theories exactly like this one but different, but exactly the same. They are all waiting on the Hadron collider to provide proof of higher order dimensions and thus not disprove their theories that depend upon higher dimensions. It will not prove which one is correct.

    If you don't believe me subscribe to new scientist for a while. Every issue a new multi dimensional theory that could help to explain some feature of the universe but can only be proved/disproved at energies that we can't reach.

    This is in essence what I'm saying. We are too far removed from being able to test these theories, that they are not likely to be correct. String theory is over 30 years old and we still haven't been able to prove or disprove it. Think about that, people have spent their entire careers working on a theory that many not be proved or disproved in their lifetimes. I think we were spoiled by the rate of rapid advance in the 20th century.

    I never said physics was not science, but more like science fiction where you don't really have to prove anything just suggest something is plausible.

    --
    Well.. maybe. Or Maybe not. But Definitely not sort of.
  6. Re:Speed of light slowing down? by MorpheousMarty · · Score: 2, Insightful

    Could you provide some links? Alan Montgomery doesn't show up in Wiki doesn't show anything and Google gets too many professors.