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NASA: Evidence Favors Infinitely Expanding Universe
Chris Gondek writes "The Sydney Morning Herald has a story here about how NASA is expected to announce this week that it has proved the existence of "dark energy," a cosmic force that counteracts gravity and will keep the universe expanding forever. The announcement will effectively demolish the theory that life will be wiped out in a "big crunch" when the universe collapses, and should end decades of academic dispute. Scientists ranging from Stephen Hawking, the Cambridge University physicist, to Albert Einstein, have argued that the universe eventually will stop expanding and then implode under the force of gravity, destroying all life. The Chicago Sun Times has also got some info."
but my money is on Hawking and Einstein, and not only because they had a handle on the metric system.
Dammit. Now I'm going to be able to feel my atoms growing farther apart all week.
This is the way the world ends
This is the way the world ends
This is the way the world ends
Not with a bang but a whimper.
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
doubt it. we still have ppl disputing that the earth is round.
So the universe won't be wiped out by a big crunch.
What a relief. I was worried.
The universe will be wiped out by the heat death of the universe instead.
(Or am I incorrect in my understanding?)
The price of freedom is eternal litigation.
So all that money that I spent on "Big Crunch" insurance is going to waste?
-Valiss
Whoa....if it's in the Chicago Sun Times then it must be true!
So instead of the Big Crunch, we get Heat Death. The universe is slowly cooling, and will eventually cool to absolute zero (killing all life), or so the theory goes.
I don't think that there is any reputable theory that doesn't have a "killing all life" at some point in the very distant future.
Pretty much what I was going to say. There's only x amount of energy, and if the universe is constanly expanding... OOPS! From one of the articles:
"Although NASA's discovery means the universe will go on forever, the same is not true for human life. As the universe expands, all of its energy will be used up."
You crazy man? You piss off supahfly!
Although NASA's discovery means the universe will go on forever, the same is not true for human life. As the universe expands, all the energy needed to keep the stars and galaxies alight will be used up. What will remain is a universe full of black holes, which after trillions of years will explode to leave nothing but dark energy
As always take this with a grain of salt.
This is the typical "blackbox" approach in science:
You have a blackbox with inputs and outputs, and you theorize what is in the blackbox based on your inputs, and what the outputs are. Sure you can come up with math/thoery that works everytime when trying to predict what the blackbox DOES. But this doesn't mean you really know what the blackbox IS (or whats inside rather).
Losely throwing out a word such as "dark energy", pretty much spells "we really have no fucking clue why to me".
sure there is something forcing our universe to expand againts the will of gravity. But it's OK to admit we don't know what it is.
Heh.. I might as well call that sludge in my sink "dark matter", and the unpleasant odour a result of "dark energy".
--noodle
Well, there goes the whole Omega Point thing. I guess there'll be no subjective eternity of omniciense and omnipotence for the likes of us. Oh, well.
This announcement has been informally known for a few weeks in the physics community. A famous cosmologist (Edward "Rocky" Kolb, FNAL) told us that it was delayed the official announcement after the Columbia tragedy.
"There is no teacher but the enemy."-Mazer Rackham
If there was a big crunch, then another expansion, maybe there would be the possibility for life again. Instead, there will be a cold death... and, it seems, eventually it will be a lot like nothing at all.
What will remain is a universe full of black holes, which after trillions of years will explode to leave nothing but dark energy.
This is true... unless there is another mechanism that transforms some of the dark energy back to normal matter. This could result in a classic steady state model.
Well, I'm no astophysicist, but won't this new theory disprove all previous theories about the Bing Bang as well, and everything we thing of the Universe thus far. If this susbstance will keep the Universe expanding forever, how was it ever possible to have a Big Bang in the first place? It would be inconcievable to think anything created the Universe in the Big Bang theory, because it could never happen, thus our Universe does not go in cycles (expand then contract - repeat).
So, How did the universe get created. Does this mean that there was actually a "beginning of time" as far as we can tell? What was that point? What existed before then? Since matter can't be created nor destroyed, where did it come from? (though that is a question beyond most planes of though, IMO)
I don't believe this story, and I think more research is needed here.
"Time is long and life is short, so begin to live while you still can." -EV
You got it, though "wiped out" isn't really the term I'd use (more like "stretched out"). It lowers the heat death temperature so that it approaches absolute zero, since the space occupied would constantly expand. Also, it's a rather lonely future even before then, as galaxies grow so far apart that you eventually can't see anything but your own big front yard.
I wouldn't get too excited, though. There are virtually no "facts" in cosmology that haven't been overthrown multiple times. This one will be no different.
"A long time ago, in a galaxy that is much farther away now..."?
Check out the Omega Point Theory... in this book. It suggests a way to use the expansion of space to generate energy to run a computer that would contain everyone's' information. Seems plausible, until he mixes its up with religion and it turns metaphysical. This theory has been promoted by Tipler, the same guy who has written many physics text books. I don't but the theory, but it answers your question about an alternate theory...
"There is no teacher but the enemy."-Mazer Rackham
Some say the world will end in fire,
Some say in ice.
From what I've tasted of desire
I hold with those who favor fire.
But if it had to perish twice,
I think I know enough of hate
To say that for destruction ice
Is also great
And would suffice.
They try to get me to accept the big bang.. but the problem I see is if everything emanated from a point source, it should not have any rotational inertia, which will be required for the spin I observe.
Maybe our observable universe is the result of the explosive contraction of a black hole? Let me elaborate: A black hole forms, and begins to accrete matter. But the matter is not falling *directly* into the hole, no, it goes round and round on its way in, going ever faster as it falls inward, spinning the hole up. Consider under the rotational centrifugal forces, the singularity forms a ring. Eventually, this ring meets the event horizon. Now, as long as the ring is not spinning fast enough to meet the event horizon, the hole is stable, but once the centrifugal force of the singularity exceeds in the tiniest amount the gravitational force holding it together, it looks like it may detonate, much like a wheel would detonate if you spun it faster than the tensile strength of the steel it is made of exceeded.
This would form the local areas we see in the universe as galaxies and galaxy clusters... and as a result of the rotational inertia of the detonating black hole which formed them, they would rotate likewise, and eventually the cycle would repeat. Endlessly. Much like a pendulum - free of friction, constantly exchanges kinetic energy for potential energy.
I'll toss this idea up the pole... comments invited.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
We eventually get ripped apart(by enthropy) rather than being crushed by gravity!
There's a growing sense that even if The Future comes,
most of us won't be able to afford it.
-- Lemmy
Not with a bang but a whimper
;)
That said, an infinitely expanding (or "open") universe is just as likely to destroy all life as the "big crunch" at the end of a collapsing (or "closed") universe. The open universe eventually winds down as all the energy in the universe become homogenized by the 2nd law of thermodynamics in a fate that is often referred to as "heat death".
If anything, the symmetric fate of a closed universe is usually considered the more hopeful fate of the universe mirroring the more traditional cyclic cosmologies of many cultures. Not only does it allow for a sort of cosmic reincarnation but also provides insight into the origin of our own universe (plus some really interesting theories as to the nature of time).
As I see it, an open universe is going to fuel some interesting debates among proponents of the strong anthropic principle (unless they are also advocates of a mischevious "trickster" creator). At least we can take solace in the possibility that matter-energy lost from our universe is "reborn" through inflation events on the far side of black holes. Otherwise, its all seems to me to be an awfully big waste of space-time
The current Big Bang theory doesn't depend on any oscillatory process in the universe. It explains the universe since 10^-43s after the Bang. before that the String Theorists specullate about the universe, and that is it.
"There is no teacher but the enemy."-Mazer Rackham
> Whew! That's a relief!
Reminds me of the story of the student of cosmology who frantically waved his hand until the annoyed professor finally called on him.
"Professor, would you mind repeating what you just said about the end of the universe?"
"I said that according to recent estimates it would take place in about 200 billion years."
"Oh, thank God, you really had me worried there for a minute! I though you said million!
According to the best cosmological theory we have now:
The universe came into being. At first, there was but one force. As the universe grew larger and colder, aspects of that one force that were hidden became apparent - these are the forces we know of now: gravity, electroweak, strong nuclear.
Consider:
Trillions of years from now, the universe is much larger and colder. Aspects of the four forces we know of now become apparent, creating new forces.
Who is to say that in a google of years, there won't be some lifeform that will look back and say (translating to English) "We aren't sure what happened in the first trillion years, but after that, the 27 forces of nature we know of began to manefest themselves..."
Who is to say that there was not some lifeform living at the first 10e-32 second that was looking forward and saying (translating into English) "One day, seconds from now, all life as we know it will cease, and the universe will be far too cold to support life."
www.eFax.com are spammers
How the hell can they predict what the universe is going to do in trillions of years, but I can't get an accurate weather forcast for the next 24 hours??
Buy the President
The assumption is that the laws of physics are uniform throughout the universe, which I also assume to be true. However, I don't assume that gravity is an attractive force, but rather one that obeys common sense, and is repulsive in nature at the quantum level.
I believe that when a graviton interacts with a particle, it pushes it along... just like any other particle interaction... but I believe that the source of the gravitons is external... and that each interaction creates a shadow... thus there would be slightly more gravitons coming at be from above, than have managed to pass through the earth to hit me from below... thus creating an apparent (and real) local gravity field, with the deficit in the downward direction.
The experiments to prove this are going to be very sneaky... but one sure proof would be that a material that stops gravitons would be very heavy, instead of having a negative weight. Even if you managed to stop some of the gravitons... then effects would be on the opposite side of the device than expected. Thus if your anti-gravity plate is put underneath a weight, it would actually get heavier... and if you put it above the plate, then it would get lighter.
The truely interesting effects occur when you get black-hole level matter density. If I'm right... then they should probably "boil off" slowly as some of the matter gets pushed out of the hole over time.
--Mike--
For a long time I have found it irritating that they talk about hypotheses like the big bang "theory" with the pretence that they have even the slightest idea what is going on.
With this new evidence, they still have no clue what the universe is up to as a whole. The whole thing was just an exercise in speculation no more informed than the Bible. It still is. It will remain that way for a very long time.
Just accept it, you are a bunch of pretentious hairless mutant monkeys living on an insignificant speck of dirt, and the universe isn't interested in bothering to tell you what is going on, and you are never going to figure it out in your lifetime.
Kind of amusing actually....
My guess is that they are talking about the results from MAP. This is a satellite that was looking at the CMB. Unfortunately, this won't tell us one bit about dark energy. What it tells us about is the total matter-energy budget of the universe. But we've known that the universe is "flat" since COBE (the last satellite to look at the CMB).
The basic way at looking at cosmological parameters is this: CMB tells us about the geometry of the universe (Omega_total = Omega_matter + Omega_energy), clustering tells us about the matter content (Omega_matter), and supernovae tell us about the acceleration of the universe (Omega_matter - Omega_energy).
Only supernovae have given us direct evidence that the universe is accelerating.
It's kind of a funny term. Heat death is actually the complete conversion of all the free energy in a system (in this case, of all systems) into the corresponding entropy. It's the victory of the second law of thermodynamics. It's not that all the energy goes away, but that it becomes so evenly spread that no further work is possible - there are no more free energy gradients to traverse. So it's not the death of heat, it's a death in heat - literally a tepid cosmos. ;)
As I noted in another message, an infinitely expanding universe means that the temperature of the heat-dead cosmos will constantly drop as the volume increases. It will asymptotically approach absolute zero.
Some others have noted that there are theories where energy and/or matter are spontaneously created in empty space. These can coexist with the heat death fate if the new energy is also evenly spread, which it probably would be in such a uniformly boring heat-dead universe. Still no way to create a new free energy gradient.
I find this an interesting fate because it's also reflected in some religions and philosophies, where everything becomes one at the end of time.
NASA definitely will not announce that they had proven the existence of "dark energy"; all they can really announce is that data they collected suggests an infinitely expanding universe. (This would not, btw, require dark energy, though an accelerating universe might; all it would require would be for the total matter and energy in the universe to be below a certain threshold level.)
I don't really know a whole lot about "dark energy" at this point... a few mentions here and there have given me a murky idea of it as similar to Einstein's cosmological constant, but nothing really definitive. Some recent evidence does, I believe, suggest an accelerating expansion which could lend credence to the theory... but I believe there have been alternative hypotheses advanced as well.
I am not a physicist, however, merely a freshman physics major. ;-) I know the NASA announcement isn't out yet so primary sources on this particular experiment are hard to come by, but can anyone suggest some background or current research on dark energy and the cosmological constant? My only real source so far has been Scientific American--that is to say, I've got no reliable sources. [grimace]
Much appreciated....
"Science is a way of trying not to fool yourself." -Richard Feynman
Hmm, yeah, well this is the first time someone has definitively claimed to have proven the answer to this issue. I don't really expect there to be any more back and forth on THIS one...
Damn, now we know the speed of gravity and the color of the universe, what's left? Let's shut down the patent office, man, science is done! Progress is so awesome - I think I'll just kick back in this technoparadise we've created until entropy consumes all things.
It Is the Nature of Information to Transgress Artificial Boundaries
Are you talking about how there is no global energy conservation due to time assymetry and Noether's theorem?
I find this an interesting fate because it's also reflected in some religions and philosophies, where everything becomes one at the end of time.
Don't most religions postulating "one" at the end of time actually have something closer to the big-bang / big-crunch? I mean the final conflagration in Heraclitus on up through the Stoics seems to have much more in common with the earlier view of cosmology. The big cruch returns everything to fire = logos that was had at the beginning of the universe. In this view the fire is raw energy and information.
I don't know of anything in traditional philosophies or religions that really corresponds to the heat death of the universe.
Is it called the "Bing Bang" or the "Big Band"?
Halton Arp, an award winning astronomer who used to be Edwin Hubble's assistant, has spent years documenting physically connected astronomical bodies with vastly different redshifts. That's simply impossible under the current theories. But they exist.
He's published several books on the subject including Seeing Red: Redshifts, Cosmology and Academic Science which presents considerable information that's been surpressed by astronomers whose theories have been threatened.
In Seeing Red, he also lays out an alternate, simplified theory, which is a _slight_ modification of the general theory of relativity that ends up predicting the real world observations without resorting to magic constants, curved space, "dark matter", and other kludges that the currently accepted theories need.
Here's some other info about it.
Evidence can be used to support anything. To prove it, though, is another thing entirely.
I think that Buddhist Nirvana sort of does; entities that become enlightened are never returned to the wheel of life, so there's a constant drain of energy "lost" by the world to nothingness. The peace of Nirvana always seemed something like a perfectly uniform universe to me. Eventually everyone on every plane is enlightened and everything is just sort of frozen (which is a way of looking at heat death, complete equilibrium being equivalent to no motion at all).
On the other hand Taoism would propose a universe that expands back into the original version of itself, since everything proceeds through an extreme, into and through its opposite, and back into itself. That's broad enough that you could fit either a big-bang-big-crunch, or a heat death where something about the uniform state causes the return of extreme nonuniformity (which is entirely possible, see below).
One of the things I find provocative about the heat death and "big egg" fates is that they're at some level indistinguishable. Once the universe is uniform, both time and space becomes meaningless, just as they do after a big crunch. So the Taoist view makes sense to me - the universe really does find its opposite (and a rebirth) at the extreme ends of time.
Oh well. I really have things I should be doing today besides discussing cosmology, if I'm to be able to afford to keep converting free energy myself. ;)
I sounds to me like all the facts are based on the red-shift seen in remote objects. Red-shift can also be caused by the decay of the speed of light. I don't know if it's true or anything, but at least it's interesting with regard to this matter - it's a theory that the speed of light in vacuum is not constant but is slowly decaying.
0x or or snor perron?!
We'd have to make some radical changes :) But at the time scales involved, I don't think a bit of engineering is going to be a problem. If any kind of life is still possible, at any speed, then a way will be found. (Remember that in a low-energy universe, slow and "fragile" processes are much more reliable than they are now. Waiting 10^9 years for a signal to pass from one neuron to another will not be a big problem.)
"This is the way the fucking world ends. Look at this fucking shit we're in man. Not with a bang, but with a whimper. And with a whimper, I'm fucking splitting, Jack."
Like a true slashdotter, I'll leave you to try to remember what it's from.
Everything that was once directly lived has receded into a representation. -debord
Well, I'm being pretty loose in my interpretations. I figure that's ok, though, because the one thing I definitely got from the University Buddhism classes I audited was that there's pretty much a variant for everyone.
;)
I have definitely seen end states described where everyone reaches Nirvana. I suspect this comes from the simple desire for a happy ending. It also more resembles endings in Christianity so that could be an influence too (but without the "hell" component, which is ongoing in most Buddhist conceptions anyway, whether you're a desire-ridden human or a hungry ghost). The alternative has infinite creation of new entities, but then you need a source for them, which kind of undoes the fact that it's an entirely reincarnation-based belief system (as with its roots in Hinduism).
It's all pretty metaphorical anyway; I also glossed over having multiple planes of existence in many or most Buddhist strains, of which this dying universe would only be one. But it beats watching TV.
A critique from a real Buddhist theologian would certainly be interesting.
Billions of years ago life crawled out of the primordial sludge.
.
Slowly over many millions of years it evolved, learned to walk upright and became intelligent enough to know that it was fucked . .
The race isn't always to the swift... but that's the way to bet!
The rate of expansion IS decreasing, the question is will that be enough to cause the crunsh or not because the rate of decrease (second derivitie of velocity) is decreasing as well.
That's the old (early 90's) model. Before the supernova data, we thought that the universe would be decelerating. However, now we're pretty sure that the universe is accelerating, not decelerating.
However, that doesn't mean that the universe won't decelerate later (or didn't decelerate earlier). There are still a lot of questions as to what the dark energy is and all of the accelerating/decelerating depends on what it is.
Google for quintessence. It's beyond my area of expertise.
Regardless of what the dark energy actually is, the universe is accelerating right now.
The human race will cease to exist in the year 2095 AD.
Sorry guys, but just don't waste your time with all this "universe big bang collapse" theory stuff, because in the end no one will be around to give a flying crap.
Hm, I'd say that's more Insightful than Funny - I mean, it is a rather serious metaphysical question if we really are facing a gloomy, dark, cold, lonely end to things, is there some way we can reverse entropy, maybe going beyond pure science and empiricism?
Anybody remember the Asimov short story, name escapes me, with the central computer that answered questions, and from time to time different generations would ask it "How can entropy be reversed?"; every time the answer was "There is as yet insignificant data to compute an answer." Eventually, mankind dies off and leaves this multidimensional hyperspatial uber-computer, which is left with one unanswered question, and it churns away, until the Universe reaches the end, heat death...and this computer finally gets the data, and the answer, and it booms out..."Let There Be Light".
Facts do not cease to exist because they are ignored. - Aldous Huxley
Several billion years ago someone got an e-mail message titled "INCREASE YOUR UNIVERSE SIZE!!!".
They hit reply and the rest is history.
Ergonomica Auctorita Illico!
Okay, great. The universe is expanding. But is it expanding quickly enough? By my calculations, the universe is not expanding quickly enough. The theoretical Heat Death of the expanding universe will not occur until long after the Starbucks Death of the universe.
That's right, the volume of Starbuckses is increasing at an accelerating rate. If this trend continues the entire universe will be filled with Starbuckses in 10^8 years, a tiny fraction of the time required for the Heat Death of the universe.
Peter
Downsize DC Today!
Although the crunch effectively puts a maximum lifetime on any specific life, there is that slim theoretical possibility that another universe would arise from the crunch. As it is, the universe grows and cools to a homogeneous soup, and that's it. We can't reuse the universe, we have to get a brand-new one.
Basically, we can think of the universe as expanding linearly with distance (hubble's law). Now, there's a very special characteristic of this type of expansion: nobody can tell if they're the center. If there were a center, it would have no effect.
Think about the raisin bread - how can a raisin tell where the center is? Remember, they don't know anything about "absolute rest" either.
Visit RTB. There's no question about it, the universe was created with life, no, human life in mind.
There will come a point when this /. thread no longer allows new replies. When that happens, if you still inclined to further enlighten me, my address is david@youdzone.com . (I assume yours is nurban@crib.corepower.com .)
I put the 'fun' in fundamentalism