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Universe May Be Running Out of Time
Posted by
Zonk
on Fri Dec 21, 2007 02:35 PM
from the ticking-clock dept.
from the ticking-clock dept.
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."
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last post! (Score:5, Funny)
Ha, you only think this is offtopic!
Pretty vague description of the problem... (Score:5, Funny)
Doctor: I'm afraid he's running out of time.
Ms. Cartman: Why, what's wrong with him?
Doctor: It's his time. It's running out.
Ms. Cartman: What can we do?
Doctor: Well, I suppose we can try a time transplant. I'll have to call a specialist.
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Re:last post! (Score:5, Funny)
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Time ... (Score:5, Funny)
CC.
Re:Time ... (Score:4, Funny)
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actually we're in a time loop already (Score:3, Informative)
ManBearPig! (Score:4, Funny)
Re:ManBearPig! (Score:4, Funny)
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EXCELSIOR!! (Score:3, Funny)
Re:EXCELSIOR!! (Score:4, Insightful)
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."
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Of course it could do anything (Score:5, Interesting)
Of course it could also flip us all upside down and turn everything a light salmon color!
Note to self: Patent method for garnering scientific celebrity. Come up with outlandish theory, then claim that LHC will move it to the mainstream.
Re: (Score:3, Funny)
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event horizon (Score:4, Funny)
kinda freakin' me out here people, if time slows down too much, it'll be 2:45 Friday afternoon forever!
3d Realms call to action (Score:5, Funny)
Time for Dr. Dan Streetmentioner's... (Score:4, Funny)
Time better not stop yet! (Score:5, Funny)
Great! Just Great!
My daughter is due early May 2008... not sure what would be worse.. my wife stuck forever pregnant, baby (diapers), or her as a teenager!
A big stretch (Score:3, Interesting)
Then again I only took one entry level university class on the whole thing so I don't think that qualifies me. I just like to think of apposing theories
Expansion, and then contraction (Score:4, Interesting)
On the other side of the balance are the black holes, which suck in energy and condense it into a singularity, which has mass. More light falls into the hole, the more massive the hole gets, the more space it sucks in, the more it shrinks the universe. At our current point in the cycle there are more stars than there are black holes, so the universe expands at an accelerating rate. As stars burn out and become black holes the expansion will slow and eventually reverse as all the radiation eventually finds its way back into a black hole. Black holes coalesce and the larger ones can explode, creating material for star formation, thus continuing the cycle. See? No mysterious dark energy is needed; only basic physics.
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Run out of time? (Score:5, Funny)
Obligatory Babylon 5 quote (Score:3, Funny)
Anyone else notice? (Score:5, Funny)
Re: (Score:3, Funny)
Failure of Context (Score:5, Interesting)
If time slows down, we slow down with it, and we don't notice because everything looks normal. This is precisely the gedankenexperiment of the moving train. If you can't handle the relativity, read some science fiction that uses it, such as Tau Zero (the ship can't stop accelerating and ends up crossing the entire universe and watching the big crunch and next big bang) or the Heechee stories (where the guy leaves the rest of his crew trapped around a black hole, and they're recovered decades later, havening spent weeks waiting).
To have an absolutely 0 tau would require a completely flat universe. As long as any matter and/or energy (dark or light) exists, this is impossible. The rate may approach 0 but cannot achieve it. Thus, there will always be duration, and we will experience it just as we do now.
Time could be speeding up and slowing down right now, like a lead foot motorist stuck in a traffic jam. We'd never notice because we're stuck in it, no matter what its rate is, like a passenger in said vehicle that can't see outside (minus the inertial effects, because we're talking the universe here, not a locally observable phenomenon).
The same argument applies to "the universe is expanding". We couldn't detect that either, because we're embedded in space time. We'd expand too. All we can see is the supposed effects of previous expansion, that of Hubble red shift. Try the dots-on-the-balloon experiment. The dots get farther apart. But the distance between them as measured by the size of a dot remains constant.
It's the same argument because time and space are integrated as space-time. It's essentially the inability to get outside a frame of reference known as "universe".
Whenever I see one of these goofy assertion articles, I hope for a summary of the math. These goofy results must be arrived at due to an error in assumption. Such an error, if considered to be a valid point, may be just the error that prevents us from integrating gravity with the other forces, and so illuminating and fixing that error could be a major step in theoretical physics.
Speed of light slowing down? (Score:4, Interesting)
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Dodgy, dodgy, dodgy ... (Score:4, Informative)
I'm also slightly disturbed by the fact that you copied your post paragraph verbatim from http://www.khouse.org/articles/1995/58/ [khouse.org], a web site that has as its mission statement, "To create, develop, and distribute materials to stimulate, encourage, and facilitate serious study of the Bible as the inerrant Word of God." Probably not the best source for a discussion of theoretical physics, methinks
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Let's all concentrate... (Score:3, Funny)
Wake-up Call (Score:5, Funny)
Perhaps something corn-based.
Fundamental error (Score:4, Funny)
When you account for this 1:4 ratio, the extra dark energy drops out of the equations, and the universe does not collapse into an academic singularity, but into four nodes, two major and two minor! The academic community will not teach this because it is brainwashing.
(Actually, I just really want this story to have the Time Cube metatag.)
But there are more than four time zones (Score:3, Interesting)
Their calculations are off because they are educated to be evil, and fail to appreciate that each day is actually four days long!.
I tried to understand what the Time Cube page meant by four days in one, where it is simultaneously morning, noon, evening, and night. And then it hit me: he's talking about time zones. In the Time Cube world, each day has a 24-hour day for each of the four non-polar faces of the cube, with time zones spaced six hours apart. But there are a lot more than four time zones [wikipedia.org] on this planet.
preprint (Score:4)
A preprint of the paper is available from arxiv.org [arxiv.org].
The general idea seems to be this. We observe that distant galaxies have an anomalously low redshift relative to the expectations of the linear Hubble relation, and we interpret this as evidence that the expansion of the universe has been accelerating. General relativity allows you to interpret a redshift as a difference in the rate of passage of time, so then an anomalously low redshift correponds to an anomalously low rate of passage of time, for us, compared to the distant galaxies, which were in the ancient universe where time was passing more quickly.
A couple of things leave me scratching my head:
Infinite universe after all? (Score:3, Interesting)
An astronaut falling toward a black hole (assuming for the sake of argument that he does not get torn apart by tidal forces) perceives that it actually takes forever to fall into the black hole. Externally we would seem him slow down and then stop at the even horizon, but this "stop" is merely the curve receding into infinity, so that further increments are so small we cannot see them. But the astronaut's subjective time becomes infinite.
So if time is slowing down locally, I guess that means in a few billion years we'll all be living in a static (albeit smaller) universe that goes on forever.
Re:We'll have to rethink everything (Score:4, Informative)
http://en.wikipedia.org/wiki/Special_relativity [wikipedia.org]
"Although special relativity makes some quantities relative, such as time, that we would have imagined to be absolute based on everyday experience, it also makes absolute some others that were thought to be relative."
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er...define 'constant'... (Score:5, Insightful)
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?
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Re:er...define 'constant'... (Score:5, Insightful)
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RTFA, please (Score:3, Interesting)
Having actually read the linked article, it's funnier. What it seems to actually say is that the time of the whole universe runs slower now, than it ran some billion years ago. It's not "dt(here)/dt(there)", but "dt(now)/dt(back-then)". If that makes any sense.
Let's say we look at the light of a star, some 5 billion light years away. The important thing there i
Re:er...define 'constant'... (Score:5, Funny)
Try to visualize this using kettles. The easiest way to slow the progress of time is to watch a kettle while it boils. If that analogy doesn't work for you, you can get a similar effect by boiling an egg or visiting a proctologist.
In order to replicate the study, you start with a single kettle (today) and then progressively add more kettles until the universe is composed entirely of kettles boiling water (end time). Kettles all the way down, as it were.
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Re:er...define 'constant'... (Score:5, Informative)
This isn't a new concept. Someone's just come up with a new theory to support the concept. This may just be another way of viewing the oft proposed heat death of the universe due to entropy.
Stephen Hawkin amongst others has explained this before. In short, time as we know it didn't exist before the Big Bang. During the inflationary period of the Big Bang time was probably faster than we observe it today. Currently time has stablised somewhat but is probably slowing due to the expansion of the universe.
All this suggests that time may be intertwined with space and now we're back to Einstein's space time continuum. This is one of consequences of Einstein's general theory of relativity.
Me? I'm going to hide under a rock with a case of beer until this all blows over.
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Re:er...define 'constant'... (Score:4, Insightful)
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 [wikipedia.org]. Now consider the metric [wikipedia.org] 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. [wikipedia.org]
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Re: (Score:3, Informative)
Re: (Score:3, Informative)
Once you understand that "time" is itself a relative term, i.e. observer-dependent, it isn't terribly hard to take any one "dt" and put it into the numerator and some other "dT" and put it into the denominator. Obvious choices that pop up in GR textbooks all over the place might include co-moving (i.e. "proper") time vs "time as seen by an outside observer".
Note that even in simple vanilla special relativity people speak of "time slowing down" for fast-moving objects. What they mean is that a pion that is
Re:Running out of time (Score:5, Funny)
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Re:Can we stop it? (Score:4, Insightful)
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Re:Add to that (Score:5, Funny)
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Re:Read the last line of the article first (Score:5, Funny)
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Re: (Score:3, Insightful)
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 th
Re: (Score:3, Funny)
Re:So we are becomming a black hole? (Score:4, Funny)
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