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Dark Energy Confirmed
bill_mcgonigle writes "By correlating the results of the Sloan Digital Sky Survey and the Wilkinson Microwave Anisotropy Probe, astronomers have confirmed the existence of dark energy.
While gravity attracts, dark energy repels, so by comparing the positions of millions of galaxies and their red-shifts with the temperature map of the early universe, evidence was found for dark energy on the scale of 100 million light years.
"Dark energy, whatever it is, is something that is not attracted by gravity" said David Spergel, a Princeton University cosmologist and a member of the WMAP science team.
"We are finding that most of the stuff in our universe is abnormal in that it is gravitationally repulsive rather than gravitationally attractive," said Albert Stebbins of the Fermi National Accelerator Laboratory. The universe is expanding at an accelerating rate, a switch that happened about 6.3 billion years ago, before which the expansion was decelerating."
The earth stops some of them passing through, and thus the ones from above us push us down. All the standard laws of physics still work on the local level, and nobody has to get a migrane trying to wrap their heads around weird concepts.
This is much simpler than "dark energy"... the farther you are from the source (or field) of gravitons (?? I have no idea where they come from), the less the "gravitational constant" appears to be.
--Mike--
The universe is expanding at an accelerating rate, a switch that happened about 6.3 billion years ago, before which the expansion was decelerating.
Must be that gosh-darn Global Warming...
Paging Mr. Gore, Mr. Albert S. Gore...
Damn, now I'm thinking of Karen... talk about repulsive being normal.
As far as I can tell, all that was confirmed was an unexplainable acceleration in the expansion of the universe.
So I just need to get me some of that dark matter, that radiates dark enery/anti gravity field, and then I can build myself my flying car. Cool
"Taligent is still pure vapor. Maybe they'll be the last who jumps up on Openstep... "
...said Albert Stebbins of the Fermi National Accelerator Laboratory.
;-)
Why do all the really clever people in the world have to be named Albert?
(Spudley Strikes Again!)
When I first studied cosmology, I wanted the theories to work out so our universe would be a series of Big Bangs that would go on infinitely. This would mean we were all part of a never ending series of events that can lead to sentient life. Now that Dark Matter is gaining acceptence, it changes things.
If the Big Bang was a one time event, and the Universe will expand forever then the question is how did this first and only Big Bang happen. What forces were at work prior to the Big Bang?
While this knowledge won't have a meterial effect on me, as I age, it's nice to know things of such a grand scale especially if the knowledge is confirmed to be true.
I hope physicists continue to make progress on Dark Matter and that Slashdot keeps posting such articles. Although I would prefer it to be on the main page.
this is interesting and yet...
now everytime i see a cosmology thread i sit and count the seconds till it erupts into an atheist vs theist debate.
Since we've only been able to play with very small amounts of antimatter we've never been able to see it's affects with regard to gravity. Maybe there's a whole lot more antimatter in the universe than we thought, and since it's the "opposite" of normal matter, maybe it has a different affect on space time, like producing anti-gravity. Of course my quack theory doesn't explain how everything doesn't come in contact and blow up, but I just barely have a HS diploma, and weird shit like this gives me a headache.
Or, antimatter is really matter, and matter is really antimatter, and we're the antimatter living in a mostly matter universe. OMG, don't touch me!
Perhaps there is some force attacting the dark matter together that doesn't affect 'normal' matter. Then the repulsive force we observe is just the dark matter displacing the other matter. Much the same way a boat seems to defy gravity by not sinking. The water (or dark matter) is in the way.
I'm sure he has known about Dark Energy for quite a while, Luke.
" You must be lost - I think the Rush Limbaugh/Ann Coulter fan club meets over on the Free Republic. In the meantime I advise you to take a basic science course."
The science is on their side. There is no evidence of global warming beyond non-human-affected climate trends.
Kyoto is all bad politics, and 0% science. Even the crank science were valid, Kyoto is bad as it allows countries to increase the supposed global-warming gases. Wasn't the goal to be to decreate them?
I misread this at first, I thought it was some sort of reference to the Slashdot motto "news for nerds, stuff that matters". My mistake.
Don't blame Durga. I voted for Centauri.
good luck getting through to our pal Al. He is busy re-inventing the Internet.
"Why do all the really clever people in the world have to be named Albert? ;-)"
Except that that b00b who went around saying that he invented the Internet.
... I'd say that I'm the MASTER OF DARK ENERGY! Buaahaha
"Derp de derp."
Rather than assuming some bizarre physics of gravitons where they pull something they ram into, why not take a simpler approach and assume that they push things along, just like a baseball and the milk bottle at the faire?
You appear to be using an overly-simplistic model of what force-carrying particles are.
The classical model of force involves "fields" - continuous distributions of force about their sources (e.g. an electric field that varies as the inverse square of distance from an object with charge, or a gravitational field that varies as the inverse square of distance from an object with mass).
When quantum mechanics came along, it was realized that these fields weren't continuous in all senses - disturbances in the field could only come in discrete packets. These are the force-carrying particles.
A graviton doesn't "ram into" anything. It's a moving ripple in the gravitational field of an object. The net effect of all gravitons (real and virtual) about an object with mass is to produce an attractive force on other massive objects nearby.
Similarly, a photon is a moving ripple in the electromagnetic field, with the net effect of all of the virtual photons in the vicinity of a charged object being to attract or repel other charged objects in the area.
The properties of gravitons are less certain, because it's hard to build a quantized version of Einsteinian gravity, but this is the general idea behind force-carrying particles (in force-carrying contexts, they can be thought of as the minimum (quantized) disturbance of a classical-looking field of force).
Now, we all know that the distance between me and the Earth will decrease over time, due to gravity. Here near the surface of the Earth, we think that the Earth stands still, and I fall toward it. I might, on the other hand, say that the Earth rises up to smack me.
In physics, we split the difference, and say that the center of gravity--the weighted average of the respective positions of the Earth and myself--doesn't move, and the Earth and I both move. I'm just stating the principle that there is no preffered inertial frame of reference.
What has this to do with your post? The "reaction" to the gravity "reaching out and grabbing" is the "puller" moving toward the "pullee."
Yes, I'm still a junky. Are you still a bitch?
...stuff like this goes and happens! I mean, GODDAMMIT I was just starting to get out the Universe worked but then....WHO ORDERED THAT!
I've enjoyed reading about physics and cosmology since I was in high school, but just didn't have the math to actually pursue it. Now I'm glad I didn't...the more the physicists and astronomers investigate, the more they realize they haven't a clue what's going on!
Maybe I'll go back to sleep and everything will be alright again...
Your suggestion amounts to either "there is no such thing as pull forces, objects can only push" or "the only forces that exist are those transferred by physical contact, ie things bumping into one another".
Lets assume (incorrectly) that your suggestion is true. What are some of the consequenses of this assumption? First, let the source be distributed at the center of the solar system. Then, according to your suggestion, the earth should move away from the sun (since the earth needs a center seeking force to continue orbiting the sun, which cannot exist if your suggestion is true). The source must then be outside of orbit of the earth (and obviously all the planets).
Where could it go outside of the solar system? It would have to be distrubuted in a circle around the solar system so that it could push in on the earth at all points of orbit. This brings up many difficulties. If the source is distributed symmetrically around the solar system, why does it push more on one side of the earth than the other? Your argument I would guess is that one side of the earth is farther from the source of the particles than the other (since the other is facing the opposite side of the source). However, according to newton's laws, the particles would lose no momentum on their way to earth unless a force is acting on them, thus the force on both sides of the earth are exactly balanced. Another problem is what happens to the particles that are coming in from both sides when they meet? We would expect some net buildup of particles (in this case, it would be at the sun). This in turn would mean the sun is becoming more massive all the time when in fact it is actually losing mass.
Now that know planets exist around other stars in our galaxy, we have to find a way for these planets to stay in orbit. Cleary we need a source of particles around each of these stars as well. In fact, since there is no reason to think any one star is more special than any other, we need a source around every star in the galaxy. Furthermore, since all the stars in our galaxy orbit our galaxy, we need a source in a circle outside of our galaxy. But wait, how do all these sources affect earth's orbit. Surely we cannot expect all the forces from the particles to magically balance out at earth. It is safe to assume, the force on the earth would no longer be in the correct direction to orbit the sun.
I have mentioned nothing about galxies orbiting in clusters (which they do). However, it is clear that you would have to make some pretty heavy modifications to your theory and add a ton of exceptions. Your theory would be about as far as you can get from an Okham's razor explanation.
There are numerous other problems to your theory (so many in fact that I don't have time to cover even a small percentage). However, I will highlight the most important aspect. Your theory makes numerous predictions that directly contradict experimental and observational results.
Please leave the theorizing to physicists and astronomers. You are not the next Einstein. Einstein may have been "just" a patent clerk, but he was a patent clerk fresh off degrees in physics and mathematics. If you continue to say things like this, you will quickly and justifiably labeled as a crackpot.
Gravity is the LACK of OPPOSING force, caused by a local absorption of this so-called "dark energy" by a local mass. In effect, gravity is a "shadow" produced by the blocking of the dark energy's repulsion from one direction. The net effect of which is to accelerate one body towards another, as each "feels" the "shadow" - the reduced opposition - from the direction of the other.
Okaaaay... then why is it that the strength of the gravitational attraction between objects depends entirely on their mass, rather than on their shape or size?
The sun and moon block the same amount of the Earth's sky. I'm sure we're all familiar with that fact that during a solar elipse, the moon almost exactly blocks out the sun. If gravity is just caused by mass blocking dark energy from one direction, then why does the Sun attract the Earth far more strongly than the Moon does? They should both block just as much dark energy.
Actually, to be fair, particle theorists have been saying for quite a while that there should be a cosmological constant, (This is what Dark Energy essentially is). Unfortunately, particle physics currently has this constant many, many orders of magnitude too high. Really the major thing about Dark Energy is it is a reversal of the previously widely held contention in cosmology that the universe was decelerating, but this is not the first time that cosmology has been reversed like this however with the new precision of measurements like WMAP it might be the last time such a reversal occurs.
Feynman discusses, and refutes, a similar theory of gravity in The Character of Physical Law .
If I recall correctly it is in the chapter where he establishes why physical law must be expressed in terms of equations. Common sense ideas like the one you mentioned are tempting, but don't seem to fit the facts we know.
Slashdotter solves major physics conundrum
Of course, I don't know which would actually be the most interesting story; that this showed up here, or that the poor pathetic bastard actually appears to think he's on to something...
Well, maybe in another decade or two your physics will be caught up to at least the 19th century.
- A precise mathematical model for what's happening
- Succinct explanations for observed behaviors
- Predictions about future behaviors, different from the predictions given to us by quantum mechanics or general relativity,
- And what evidence could come up which would totally disprove your theory
... Until you do that, you're smoking crack. Once you do all this, then you've got a scientific hypothesis, and that'll be worth listening to.Until then, get thee away from me, crack-monkey!
Sorry, I meant mass _and distance_. The strength of gravitational attraction depends on both. Doesn't change my argument any, though.
Here's my theory about dark energy and the accelerating universe.
:-)
Imagine that space is really on a 4-dimensional sphere and the big bang happened at one point on this sphere. (Picture space as a globe and imagine the big bang happened at the north pole.) Everything rushed away from this point but was being slowed down by gravity. At some point, the matter passed the "equator" and is now attracting instead of repelling. In the future, we would have a big crunch on the opposite side of the sphere (the south pole) from where the big bang happened.
The article mentions that the expansion of the universe was decelerating until about 6.3 billion years ago, then it began to accelerate. That means the universe may end when it is only 12.6 billion years old. That's roughly the age of the universe, so we can all expect to die shortly.
IANAP of course, but I thought it was a fun idea
This sounds a lot more like a re-statement of the reason that people started theorizing that "dark energy" might exist. Confirmation? pfft.
Mr. Hawk "We dont know why this is happening."
Mr. Beard "Hmm,, maybe it's 'Dark Energy', that acts in reverse."
Mr. Hawk "Hey look, the same thing is happening over here.. I wonder why.."
Mr. Beard "This conclusively proves my earlier hypothesis!!"
-- 'The' Lord and Master Bitman On High, Master Of All
We are finding that most of the stuff in our universe is abnormal ....
Now wash your hands.
Back in the 70's William G. Tifft noticed that the red shift of light is quantized
(there are heaps of other pages if you do a search)
Based on this research, the red shift of light can't be based on velocity (as that would result in a smooth distribution of values, not discreet units). Therefore any assumptions about "dark" matter are based on an invalid assumption.
I have my own theories about this quantisation, but I haven't gotten around to writing a physics paper yet.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
Occam's Razor is a terrible way to logically reason something out. First of all, in science, one assumes an infinate number of factors which must be controlled for - secondly:
Occam says: "God did it."
Provide me with a simpler explanation that uses less entities?
I'm still waiting for my super-symmetrical beer.
Q.
Insert Signature Here
Q.
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* Mathematical Model - So-called "attraction" (force) is equal to the product of the two masses, the gravitational constant (G) and the inverse square of the distance between the masses. (Physics 101)
* Succinct explanations - You're joking, right? Apple falls, hits Newton on the head, blah blah blah...? (Physics 101/History 201) - though it's disputed whether or not the apple actually hit him.
* Predictions about future behaviors - What ARE you talking about? What does "behaviors" have to do with the source of the gravitational force? Behaviors are reserved to systems (including living beings, for the sake of argument). The force in question is a force, expressed as a vector. It has a magnitude and a direction. That's it. Any "behavior" would be an attribute of the system that the force is being considered within. These behaviors do not speak to the magnitude, direction, (or source, for that matter), of the gravitational force itself.
* What evidence could come up with [sic] - If I had evidence to disprove my theory, the scientific method would require me to withdraw it from consideration. Since I have no evidence to disprove it (for now), it's still my hypothesis.
Of course this is science. Research "The Scientific Method". In simple terms it flows as such - A) Observe. B) Create hypothesis. C) Test hypothesis. D) If test fails, discard or modify hypothesis and return to C). If test succeeds, either return to C) directly, or modify hypothesis and return to C).
BTW - I value my mind and my physical health far too much to destroy either with smoking (crack or otherwise).
I always thought that this was malarky, and now they're trying to shove it to us like its proof or something. Let's get this straight: until someone can harnest this 'dark energy' and prove to me it really exists, well, I'm not going to believe it. Instead I'm going to believe that gravity is a resultant factor of a lot of mass being in generally one place. Since I also theorize that matter is made of waves that are condensed into tangled balls of electromagnetic energy (sorry, no better definition for "energy traveling in a 3d waveform"), it's simple to believe that the size of atoms are not tiny balls of matter, but instead gigantic clouds of electromagnetic energy, probably reaching miles in diameter, with a super condensed core. It's hard to explain but by lots of these being in one region, its simple to see how gravity works, especially on objects with a velocity vector. But explaining that might take a little while.. But then again, IANAP, although I'de like to be one.. especially if i can prove this waveform partical existance theory.. making teleportation a very simple thing to knock out...
"Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
Yes, even if the absorption is proportional to the gravitational mass, then the shadow theory of gravity clearly predicts a decay of angular momentum of all orbits. The gravitational force would be skewed by the transit delay of the dark energy.
Michael J. Burns
Now we've been decelerating...then accelerating?
This is the thing that has been driving me absolutely crazy vis-a-vis the Big Bang theory, is that the practitioners seem to operate under the maxim:
"Keep adding terms until the data fits"
That's not the way science is supposed to work.
We've had a fair share of juggling of terms, including:
- "Big Crunch" - gravity will let the universe collapse again
- "Flat Universe" - universe will expand forever, but keep slowing down
- "Inflationary Universe" - universe expanded faster than the speed of light for a tiny moment (addressing the age and isotropy problems)
- Not sure what to call this... "Second wind universe" - universe slows its acceleration before dark energy becomes the reigning cause of repulsion
I sincerely doubt it will end there - the Missing Mass problem and the Age of the Universe problem will push the equations incrementally.The Hubble telescope observations are getting awfully close to the predicted age of the universe. I wonder what age-of-the-universe estimate this new theory will predict; something more than 13.7 billion years?
The missing mass in the form of dark matter is, by all accounts, supposed to be mass that attracts; the inflationary universe theory depends on it for flatness. This might be another move 'around' the problem.
The Big Bang theory fell from grace for me over a period of fifteen years. While I don't subscribe to the notions of Velan, I'm curious, yet ambivalent about Alfven's plasma cosmology, there are a number of viable cosmological theories that don't have age, mass or exotic physics problems. It seems we closed the book on alternatives too soon, and are constantly interpreting data so it fits with theory, instead of breaking the back of theory on data.
Proving mathematically that you can never hit a wall must be tempered with observations of a hole in the wall and drunk in front of said wall on his back at a frat party :)
Binary geeks can count to 1,023 on their fingers
Actually, Mike, such a mechanism was proposed by George Lewis LeSage in 1784. The theory keeps on getting shot down, then revitalised in periodic cycles. There are those who have derived Newton's equations from this sort of paradigm, and there are those who have indicated that if gravitons (assuming such a particle is involved) go at the speed of light, there might be problems with orbits.
I prefer to wait and see on the subject. I'm just waiting for the book Pushing Gravity: New Perspectives on Le Sage's Theory of Gravitation to arrive for yet more "light reading" :)
Side thought: I think I got my don't-close-the-door-on-them attitude to these various theories from being a good debugger. If reality is anything close to the way debugging operates, the same symptom can have multiple causes, but any instance really has one cause...
...and it's hardly ever what any of your initial guesses were, regardless of how sensible they seemed. ;)
Binary geeks can count to 1,023 on their fingers
A)succinct explanations for observed behaviors means that you find a behavior which *can't* be explained with the competing gravitational theory, and can be with yours.
B)Mathematical model, and why does your model depend on the mass of the observed bodies instead of a property of the repelling energy?
C)What evidence could come up with doesn't mean that you find the evidence, but that you imagine which evidence would prove your theory wrong (ever heard of Karl Popper?). You know, as in C) Test hypothesis. What is your test?
Btw, the fourh step in the algorithm of scientific method should be return to *A*, not *C*. Always go back to the facts, if you want science.
Forgive me if I was rude.
Singularity: a belief in the "God" idea with the "demiurge" relation inverted.