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Space Science

Fermilab Reports Dark Energy Not Needed 416

An anonymous reader writes "A Fermilab press release reports that the expansion of the universe may be explainable without the need for dark energy or a cosmological constant. Apparently, ripples from inflation in the early universe may account for the observed expansion rate of the universe."
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Fermilab Reports Dark Energy Not Needed

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  • by brilinux ( 255400 ) on Thursday March 24, 2005 @08:22PM (#12041408) Journal
    Nothing for you to see here. Please move along.

    Well, apparently the dark matter is still important on Slashdot.

  • by mr100percent ( 57156 ) * on Thursday March 24, 2005 @08:22PM (#12041409) Homepage Journal
    But what about the Horizon problem?

    From an earlier /.-linked article 13 things that do not make sense [newscientist.com]:

    The horizon problem

    OUR universe appears to be unfathomably uniform. Look across space from one edge of the visible universe to the other, and you'll see that the microwave background radiation filling the cosmos is at the same temperature everywhere. That may not seem surprising until you consider that the two edges are nearly 28 billion light years apart and our universe is only 14 billion years old.

    Nothing can travel faster than the speed of light, so there is no way heat radiation could have travelled between the two horizons to even out the hot and cold spots created in the big bang and leave the thermal equilibrium we see now.

    This "horizon problem" is a big headache for cosmologists, so big that they have come up with some pretty wild solutions. "Inflation", for example.

    You can solve the horizon problem by having the universe expand ultra-fast for a time, just after the big bang, blowing up by a factor of 1050 in 10-33 seconds. But is that just wishful thinking? "Inflation would be an explanation if it occurred," says University of Cambridge astronomer Martin Rees. The trouble is that no one knows what could have made that happen.

    So, in effect, inflation solves one mystery only to invoke another. A variation in the speed of light could also solve the horizon problem - but this too is impotent in the face of the question "why?" In scientific terms, the uniform temperature of the background radiation remains an anomaly.

    "A variation in the speed of light could solve the problem, but this too is impotent in the face of the question 'why?'"

    Also, in the same article, Dark Energy is discussed:
    9 Dark energy

    IT IS one of the most famous, and most embarrassing, problems in physics. In 1998, astronomers discovered that the universe is expanding at ever faster speeds. It's an effect still searching for a cause - until then, everyone thought the universe's expansion was slowing down after the big bang. "Theorists are still floundering around, looking for a sensible explanation," says cosmologist Katherine Freese of the University of Michigan, Ann Arbor. "We're all hoping that upcoming observations of supernovae, of clusters of galaxies and so on will give us more clues."

    One suggestion is that some property of empty space is responsible - cosmologists call it dark energy. But all attempts to pin it down have fallen woefully short. It's also possible that Einstein's theory of general relativity may need to be tweaked when applied to the very largest scales of the universe. "The field is still wide open," Freese says.

    • by Anonymous Coward
      If the universe is 14 billion years old, and the edges are nearly 28 billion light years apart, what's the problem? It expands at relativistic speeds 14 billion years one way, 14 billion years the other. 14*2 = 28. So unless they're stating this wrong, shouldn't that be the way that it works?
      • I think it's because for it to be that big, all matter and energy in the universe would have to have exceeded the speed of light to be where it is today or at least be moving at the speed of light away from the epicenter. Also, it doesn't account for the time needed for the universe's background radiation to become uniform (even out over time)
        • > ...moving at the speed of light away from the
          > epicenter.

          There is no epicenter.
        • by WaterBreath ( 812358 ) on Friday March 25, 2005 @01:13AM (#12043345)
          A few things:

          According to "accepted" theories of expansion, there is no epicenter. All space is expanding equally in all directions. So wherever you are standing, everything will appear to expand outward away from you.

          Because of that, things farther away from you will be receeding from you faster, because every extra bit of space between you and them means an extra bit of expansion, and so an extra bit of recession speed. As the theory goes, superluminal recession speeds are possible because the distant objects are not actually moving relative to the stationary frame of space in their vivinity. Space itself is changing shape, and the "motion" we see is just a side-effect.

          Supposedly, there is a certain distance, which can be measured starting at any given point, beyond which every everything is receeding from the reference point faster than light, and so will never be visible from that point. This is called the Hubble distance. Related is the Hubble constant, which is a measurement of change in velocity of expansion per unit distance from the reference point. (Not the odd way to measure acceleration. Normal acceleration is m/s/s, or m/s^2, but this is m/s/m, or just 1/s, which is 1Hz. Weird, eh?) The Hubble constant is under contention, I think, and the value of the Hubble distance depends on the value of the constant.

          Anyway, this stuff is kind of where the idea of Star Trek's "warp drive" comes from (at least in the more recent series). If it were possible to create some sort of device that could cause the space in front of a ship to contract and the space behind to expand proportionally, the ship could move without moving through space. It would be space itself changing shape around the ship that causes it to "move". And hence the speed at which you could move would be limited only by the speed at which you could channel energy into the expansion and contraction of space. Of course, this might just happen to be limited by the speed of light as well, so maybe superluminal speed still wouldn't be possible!

          But if these guys' new idea is right, then none of that matters. =)
          • The problem with the theory wasn't so much you couldn't move faster than the speed of light (apparently this was a valid way to "cheat" according to the calculations). It was that the amount of energy required to maintain such a bubble would be powerful enough to instantly destroy any event causing this phenomenon in the first place (aka a warp drive). It was akin to being inside a extremely unstable black hole.
          • There is no epicenter like there is in an earthquake, but you can define any position at rest in the frame of the background radiation itself to be as good of an "epicenter" as any other for purposes of this discussion. The Earth doesn't meet this standard, because it's moving at a speed of 365 km/sec relative to the CMBR (hence the Doppler shift), but it probably doesn't matter.

            Here is a good FAQ entry regarding the difference [ucla.edu] between the observable universe and the entire universe.
      • Comment removed (Score:4, Interesting)

        by account_deleted ( 4530225 ) on Thursday March 24, 2005 @09:43PM (#12042020)
        Comment removed based on user account deletion
      • If the universe is 14 billion years old, and the edges are nearly 28 billion light years apart

        It's not.

        Our perceptable universe is 28 billion light-years apart. We have no way of knowing how much larger the universe is, because no information from beyond our information-cone can get to us.

        (Graph space and time on an X-Y axis. Pick a point on Y, time, and draw two 45-degree lines down the page. As time progesses, the distance that we can get light from increases, because light has a finite speed. Tha
    • by PureFiction ( 10256 ) on Thursday March 24, 2005 @08:34PM (#12041512)
      If you read the article you would see they address this issue. The key is to realize that the horizon extends beyond what we can see (our cosmic horizon):
      • It is widely believed that during the inflationary expansion early in the history of the universe, very tiny ripples in spacetime were generated, as predicted by Einstein's theory of General Relativity. These ripples were stretched by the expansion of the universe and extend today far beyond our cosmic horizon, that is over a region much bigger than the observable universe, a distance of about 15 billion light years. In their current paper, the authors propose that it is the evolution of these cosmic ripples that increases the observed expansion of the universe and accounts for its acceleration.


      • "We realized that you simply need to add this new key ingredient, the ripples of spacetime generated during the epoch of inflation, to Einstein's General Relativity to explain why the universe is accelerating today," Riotto says. "It seems that the solution to the puzzle of acceleration involves the universe beyond our cosmic horizon. No mysterious dark energy is required."
    • I was going to moderate your comment "interesting", but then I realized all of this is just hypothesis so it doesn't really belong outside the original study group.

      two edges are nearly 28 billion light years apart and our universe is only 14 billion years old.

      In 1998, astronomers discovered that the universe is expanding at ever faster speeds. It's an effect still searching for a cause - until then, everyone thought the universe's expansion was slowing down after the big bang.

      A true scientific perspe

      • According to a recent scientific american article that was written to debunk common myths about the universe, given that the universe is expanding, the visible universe is actually larger than 14 billion ly radius. This is because light from a star that is *now* 30 billion ly away could have reached us by now because for part of its trip it was closer than 30 billion lys from us. This is, of course, assuming that light goes at a constant speed.

        The problem with all this highly theoretical physics is that no
    • But what about the Horizon problem?

      The work in this article assumes that inflation is right. People don't like inflation because they don't know how it happend, but something like it had to have happened in the early universe.
    • ...eddies in the space time continuum.
    • IT IS one of the most famous, and most embarrassing, problems in physics.

      Obviously a physicist didn't write this article. When something unexpected happens in the field of physics, physicists are not embarassed, there is rather much rejoicing among the people of science. The TOE [wikipedia.org] aside, we in the pursuit of pure research do not concern ourselves with the prerogative of questions or the solving of problems, rather we are in the business of finding new questions and new classes of questions to ask. This

    • by niktemadur ( 793971 ) on Thursday March 24, 2005 @09:44PM (#12042041)
      While it is a generally accepted law that nothing WITHIN space can travel faster than light, this law may not apply to SPACE ITSELF, which could inflate at superluminous speeds if the correct conditions are present.

      I know this sounds bizarre, and I'm no expert on the subject, but I'll try to give a simple example that even I can understand:

      Let's say space is like a balloon.
      Matter are the molecules within that balloon.
      The matter within may not move faster than light by its' own means.
      But the balloon may inflate faster than light, and the matter within goes along for the ride.
      At the end of inflation, the matter has kept its' same relative position in space.

      The correct condition for inflation to happen is known as supercooling. Here is an example that Alan Guth used to describe it: water that's below 32 degrees farenheit but retains its' liquid state. However, just gently tap the plastic mold and the water will abruptly crystalize into ice before your very eyes. Supercooled water.

      Another example would be a beer in the freezer that's liquid, but turns to ice from the top down when you open the lid. Supercooled beer.

      Accordingly, the universe would have to inflate at a certain speed (much faster than light) to re-attain its' appropriate state under specific conditions.

      According to Alan Guth, most of the universe's matter cancelled itself out instants after the Big Bang, due to matter-antimatter collitions. In a super-excited state, the universe found itself almost empty, and had to readjust by inflation and a spontaneous burst of creation of matter. In fact, Guth said that with 28 pounds of matter under the right conditions, a universe just as massive as ours could be created. This is why Guth said that our universe could be the ultimate "free lunch".
    • But what about the Horizon problem?

      Inflation solves the horizon problem. According to this latest calculation (see TFA), inflation also leaves some UBLW (unimaginably long wavlength) gravitational waves that account for the apparent acceleration of the general expansion, without the shamefully ad-hoc introduction of dark energy.

    • You can solve the horizon problem by having the universe expand ultra-fast for a time, just after the big bang, blowing up by a factor of 1050 in 10-33 seconds. But is that just wishful thinking? "Inflation would be an explanation if it occurred," says University of Cambridge astronomer Martin Rees. The trouble is that no one knows what could have made that happen.

      Unforch, either the exponent was forgotten, or got lost in an html glitch someplace, What I'm refering to is the 1050 figure used above, whic
  • So basically (Score:2, Insightful)

    They don't need somethings they invented to explain away what they didn't understand.
  • Difference? (Score:2, Interesting)

    Can someone tell me, what's the difference between Dark Matter and Dark Energy?
    • Re:Difference? (Score:5, Informative)

      by Pfhorrest ( 545131 ) on Thursday March 24, 2005 @08:37PM (#12041530) Homepage Journal
      The other responses to this thus far are completely off. Dark matter and dark energy are not (by any current theory at least) related anything like how normal matter and energy relate via e=mc^2.

      Dark Matter is a hypothetical unknown "stuff" with normal mass just like regular matter but which we cannot observe with light; it doesn't appear to be emitting or noticably obscuring any kind of radiation. But we see the movement of galaxies in such a way that they appear to be responding to the mass of something that we can't see. Hence "dark matter" - we can't see it, but it seems to be some sort of matter. Think of it like leaves blowing in the wind - we can't see the wind, but we see the motion is causes.

      Dark Energy is another hypothetical unknown "stuff" that seems to be adding, somehow, to the velocity of all objects in the universe. It is postulated because the universe appears to be accelerating in its expansion, which does not make sense given an empty, neutral vaccum and a bunch of matter in it. It should be slowing down or at best, expanding at a steady rate. Hence "dark energy" - we can't detect it, but some source of energy which is causing the expansion of the universe to accelerate.

      Hope this helps.
      • Hence "dark matter" - we can't see it, but it seems to be some sort of matter. Think of it like leaves blowing in the wind - we can't see the wind, but we see the motion is causes.

        maybe more surch dark matter is leaves ,and we can see wind ,but we can`t see leaves (can, but whence if not)
    • Re:Difference? (Score:2, Informative)

      by Aglassis ( 10161 )
      It has been observed that galaxies on the whole do not obey Kepler's Laws of Planetary Motion. In particular, stars along different positions moving outwards from the core have about the same measured period (to do a complete orbit of the core). Kepler's Third Law says that the square of the period of a star is directly proportional to the cube of the stars' semimajor axis. Stars further out should have a much longer period (like Pluto) than those close to the core. Dark matter is an invention that comp
  • by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Thursday March 24, 2005 @08:24PM (#12041426) Journal
    If there was nothing to push against, what would cause something to be held back and "ripple" as if there were some sort of repulsive force?

    Let's say we've reached the edge of the universe, what happens when we step beyond that boundary? What is out there that would possibly hold back further expansion of our universe?
    • by TrekkieGod ( 627867 ) on Thursday March 24, 2005 @08:50PM (#12041641) Homepage Journal
      If there was nothing to push against, what would cause something to be held back and "ripple" as if there were some sort of repulsive force?

      Not really related to the ripple they are talking about in the article, but "repulsive force" doesn't require something to push against. When students first learn of Newton's third law, "for every action, there's an opposite and equal reaction", teachers often give as an example that when you push against a wall, the wall pushes against you. That gives the idea to students that there must be something to push back against you (don't feel bad, some early rocket scientists thought the same thing). That is, however, not true. You don't need something to push against, you just need to exert a force in one direction, and there will be a a force in the opposite direction.

      Because of this misconception, it was originally thought that rockets wouldn't work in space, because the exhaust they put out wouldn't be able to push against the atmosphere. But hey, they do!

      Let's say we've reached the edge of the universe, what happens when we step beyond that boundary? What is out there that would possibly hold back further expansion of our universe?

      Gravity. There's an attractive force between every object with mass. When you jump, you move away from the center of the earth, but only for a short time. You accelerate up, but then you start decelerating. You reach a maximum height, then you start accelerating back down. During the big bang, the universe started expending. It was originally thought that there would be a "big crunch", and the universe would stop expanding, than start collapsing towards the center. Then we discovered the universe was not only not slowing down in it's expansion, but actually accelerating. That made no sense, so Dark Energy was used to explain it (a force like gravity, but pushing outwards). Under that scenario, the universe would end not through a big crunch, but would simply become dark as suns die and black holes evaporate. If we don't need Dark Energy, maybe the big crunch theory will come back.

      • by Anonymous Coward
        You still need something to push against in order to create those ripples. Unlike vector thrust which only requires a directed force, a ripple requires a reflection of an energy wave.

        Let's take a very simple example of a wave in water. It has a wave front and the energy contained in the wave form continues in a straight line until deflected or it runs out of energy due to friction. The only way to get a ripple is to reflect the energy back upon itself (like hitting a solid barrier). But even then, some
      • When students first learn of Newton's third law, "for every action, there's an opposite and equal reaction", teachers often give as an example that when you push against a wall, the wall pushes against you. That gives the idea to students that there must be something to push back against you (don't feel bad, some early rocket scientists thought the same thing). That is, however, not true. You don't need something to push against, you just need to exert a force in one direction, and there will be a a force

        • by Almost-Retired ( 637760 ) on Friday March 25, 2005 @12:40AM (#12043083) Homepage
          Uhmm ... rockets work due to conservation of momentum, not because of some mysterious reaction force.

          Not a very good explanation. Rockets work in space because the exhaust gases are, in the process of being accelerated out the back of the engine, are pushing equally hard on the walls of the engine thats burning the fuel. Since thats cone shaped, wider at the rear, its the net circular square area of the back flange of the motor that the gasses push against, and its anchor to the rest of the rocket transfers that push to the rocket proper. And don't forget that a little like the e=mc2 of Einsteins famous equation, the net power, minus some losses here and there, is still e=mv2, so the holy chalice/grail of the rocket is the one that moves the gas at the highest velocity at the face of the nozzle, with some of the flame cone actually being a velocity to pressure translation so in the end, the gas velocity, being highest out near the tip of the flame, serves to increase the felt pressure pushing forward on the engine proper.

          The ion and plasma drives that use zenon gas, electrostaticly or thermally accelerated to a fraction of C speed, are many times more efficient in terms of the amount of push per pound of expendable than any chemically fired rocket can ever hope to be simply becasue of the 'fraction of C speed' is many times what a chemical fired gas generator can do.

          I've heard/read of estimates that a xenon gas rocket, fired by a nuclear light bulb heat source (circa 30,000 degrees C) making a plasma out of the gas, could go to Alpha Centari in just a few years, as it would accelerate at a steady .05G's to the halfway point, then turn around and decelerate at that same rate. THat of course means it would have to be launched into leo by some other means before lighting the torch. If not turned around and slowed down, it would go by Alpha Centari at truely relativistic speeds, near .99 C. I haven't personally ran the math, but the article I read 2 decades back sure did. ISTR the article said it would only take about 20 tons of gas. That was with estimates of about 5 tons for the whole nuclear light bulb reactor so the total vehicle weight wouldn't be near as heavy as a Saturn5 at launch. We played with such a reactor at Rocky Flats for a while, but the natives (thats us people folks) got restless. I don't know if there ever was a true 'accident' involving one of them because basicly if the 'light bulb' envelope fails, the reaction is self quenching. One of the safest reactors ever developed, but the word nuclear was its death knell.

          Sometimes I swear we are our own worst enemy.

          --
          Cheers, Gene
          "There are four boxes to be used in defense of liberty:
          soap, ballot, jury, and ammo. Please use in that order."
          -Ed Howdershelt (Author)
          99.34% setiathome rank, not too shabby for a WV hillbilly
  • "It requires only a proper accounting of the physical effects of the ripples beyond our cosmic horizon,"

    Ripples of what? Is there space beyond the cosmic horizon? Or by horizon they meant observable part of Universe?
    • by ari_j ( 90255 ) on Thursday March 24, 2005 @08:32PM (#12041496)
      Yes, there is space beyond the cosmic horizon. The horizon on Earth is just the farthest you can see because of the curvature of the planet's surface. The planet keeps going beyond the horizon - the horizon is a function of the observer. The same applies to the universe, although I am not knowledgeable enough to tell you if the cosmic horizon is the limit of what we can see because of the distance, because of a higher-dimensional curvature of the universe, or because of something else.
      • by Anonymous Coward
        although I am not knowledgeable enough to tell you if the cosmic horizon is the limit of what we can see because of the distance, because of a higher-dimensional curvature of the universe, or because of something else.

        Because of light speed. Since nothing can travel faster than light, you can't receive a signal from anywhere in the Universe that is farther from you than the distance light could have travelled since the formation of the Universe (14 billion years approx.)
  • by ackthpt ( 218170 ) * on Thursday March 24, 2005 @08:27PM (#12041442) Homepage Journal
    Apparently, ripples from inflation in the early universe may account for the observed expansion rate of the universe."

    Hmm. Better check the exchange rates on Altairian Dollars, Flainian Pobble Beads and the Triganic Pu.

    Has anyone contacted Alan Greenspan about this?

  • Comment removed (Score:5, Informative)

    by account_deleted ( 4530225 ) on Thursday March 24, 2005 @08:27PM (#12041443)
    Comment removed based on user account deletion
  • by starling ( 26204 ) <strayling20@gmail.com> on Thursday March 24, 2005 @08:29PM (#12041467)
    Arthur : Oh, is he?

  • string theory Nova (Score:5, Interesting)

    by Fox_1 ( 128616 ) on Thursday March 24, 2005 @08:30PM (#12041474)
    Nova did a great piece [pbs.org] on the all of physics (a lot on the universe and big focus on Quantum Mechanics and String Theory). It's pretty good if you are trying to find commonplace explanations of some of the theories the article just mentions and doesn't explain.
    • That would be The Elegant Universe, by Brian Greene. It's actually based on a book that he wrote, which is EXTREMELY well-written. I highly recommend it if you're at all interested in this stuff.
    • Might be redundant, but you can watch the show online by clicking a link on that page. Quite decent quality.
      There is also a HDTV .torrent out there - 3.14 GB, much nicer quality.
    • FAR more interesting than The Elegant Universe is his subsequent book The Fabric of the Cosmos: Space, Time, and the Texture of Reality. I highly recommend this to anyone that was interested by his earlier work or the various discussions here.

      Most posts here seem to be quoting science from decades ago. The errors and misconceptions too numerous. It is clear that many have no idea how far we have come in understanding everything all the way back to and including time zero, including what even caused the
  • So it is like when Wile E. Coyote yanks the road up and down and the ripple gets bigger and bigger as it moves toward the Roadrunner? (and then bounces off a mountain side, comes back, and smashes Coyote.) Next you know they will find a giant U magnet at the edge of the universe.
  • WWDVS? (Score:5, Funny)

    by LokieLizzy ( 858962 ) on Thursday March 24, 2005 @08:34PM (#12041514)
    (What would Darth Vader say?)

    "Do not be so proud of this cosmological terror you have created. Its existence pales when compared to the power of the Dark Side."

  • I'm not an expert... (Score:5, Informative)

    by chazR ( 41002 ) on Thursday March 24, 2005 @08:34PM (#12041517) Homepage
    but Sean Carroll [blogspot.com] is. And he's not convinced.
  • Gravity leaks (Score:5, Interesting)

    by Tablizer ( 95088 ) on Thursday March 24, 2005 @08:35PM (#12041521) Journal
    I've read another hypothesis recently: that gravity slowly "leaks" into other dimensions so that over long distances it's attractive force diminishes, and that is why the universe is flying apart. The average distances between the galaxies has now reached a threashold where the leakage makes a big difference, giving the appearence of a relatively sudden expansion speedup.
    • Re:Gravity leaks (Score:4, Interesting)

      by XanC ( 644172 ) on Thursday March 24, 2005 @08:53PM (#12041676)
      Even if gravity were zero, the universe would then expand at a constant rate. But it appears to be accelerating, implying some kind of negative gravity.
    • Re:Gravity leaks (Score:4, Informative)

      by Stalyn ( 662 ) on Thursday March 24, 2005 @09:44PM (#12042036) Homepage Journal
      The hypothesis in question was explained here [space.com]

      Also here [uchicago.edu] for the braver souls.
  • "Apparently, ripples from inflation in the early universe may account for the observed expansion rate of the universe." "

    Does anyone still have one of those "WIN" buttons left? Perhaps if enough of us wear them, we can stop the catastrophic overexpansion of the universe.

  • by sharkey ( 16670 ) on Thursday March 24, 2005 @08:46PM (#12041607)
    Then there's no need for Branigan's Law.
  • Seriously now (Score:2, Interesting)

    by Camel Pilot ( 78781 )
    The universe is expanding at an accelerating rate not because of some dark matter but because of the gravitational attraction of other universes in the local vicinity of our own. sheeshh why do folks want to believe we are special with our own little private universe.

    Just like at various times in history, humans believed that our tribe was the center of the universe, then the earth, then the sun, and now no one wants to think "outside the box" so to speak, and so they invent dark matter to account for obse
    • Interesting? (Score:3, Interesting)

      by MustardMan ( 52102 )
      Seriously, how did this get a mod as Interesting? He bitches about the arrogance of humans thinking we are the center of everything, then is INSANELY arrogant in stating his own theory as if it were an indisputable fact, while providing NO evidence to support it.

      The whole POINT of the term "dark energy" is to say "there's something funny here and we don't know what it is". I'd say that's one regulation shitload less arrogant than camel pilot's claim.

      By the way, I'm far from a cosmologist, but the poster
  • The mystery of why the universe is expanding more rapidly rather that slowing down is explained easily with the following theory:

    'Our' Universe actually resides within a red rubber ball that belongs to gigantic beings, and it is currently being inflated

    I simply fear they will begin playing dodgeball soon.
  • by Omniscientist ( 806841 ) <matt@ba d e cho.com> on Thursday March 24, 2005 @08:50PM (#12041650) Homepage
    "Whether Einstein was right when he first introduced the cosmological constant, or whether he was right when he later refuted the idea will soon be tested by a new round of precision cosmological observations," Kolb said.

    So either way, Einstein was right. Damn you Einstein!!!

  • by secolactico ( 519805 ) on Thursday March 24, 2005 @08:50PM (#12041651) Journal
    Fermilab Reports Dark Energy Not Needed

    Well, thank god! I was going crazy trying to find some.
  • Saw this article a few days ago and it talked about Alpha- raised all sorts of questions for me (being a non-enlightened individual) such as

    a) What are the implications if Alpha is 'decaying' with time?
    b) What are the implications if alpha is variable with graviational mass?
    c) If enough photons were gathered in one location, would they have a 'gravitational' effect... and would that affect any known 'constants'?

    Tantalizing and interesting, but I know I lack the education to understand all of the ramifications.
  • by LokieLizzy ( 858962 ) on Thursday March 24, 2005 @08:55PM (#12041691)
    I'm not a scientist.

    But I did stay at a Holiday Inn last night. And when the lights went out at midnight (power outage), I can assure you that there was more than a little energy going on in the room next door.

  • If there wasn't a Dark Force already...

    ...George Lucas would invent it!

  • sometimes, that these silly physicists just over-think everything?

  • by stox ( 131684 ) on Thursday March 24, 2005 @09:18PM (#12041837) Homepage
    Their budget has been slashed almost in half. After all, low quality bombs are far more important than high quality science. In fact, spending on basic research is dropping at an alarming rate through all the national laboratories. This does not bode well for our future.
    • Welcome to the era of government run by the conservative right. We can only hope that the supreme up-fucking that is privatization of social security will lead to a massive backlash and maybe we'll actually get some SANE people into office.
    • Their budget has been slashed almost in half. After all, low quality bombs are far more important than high quality science. In fact, spending on basic research is dropping at an alarming rate through all the national laboratories. This does not bode well for our future.

      This isn't quite true. DOE's funding for High Energy Physics Programs (basically, Fermilab and SLAC) is down 3.1%, or $22.5 million, from $736.4 million to $713.9 million. (I couldn't find out exactly how much Fermilab lost from those cuts
  • is always and everywhere a monetary phenomenon.
  • by sPaKr ( 116314 ) on Thursday March 24, 2005 @09:41PM (#12042011)
    The producers of Startrek Enterprise gave themselves concusions from repeated blows of their heads to their desks. One producer cried "Ripples in space time explain the universe, WHY COULDNT WE GET THESE GUYS AS WRITERS!'
    • by ari_j ( 90255 ) on Thursday March 24, 2005 @10:39PM (#12042393)
      How about

      COMES NOW the plaintiffs, who allege:

      1. Plaintiffs are producers of the TV show Star Trek: Enterprise.
      2. Defendants are the class of all scientists in the world.
      3. Defendants stole and used as their own a plot device from the Star Trek: Enterprise finale; namely the idea that ripples in space-time explain the universe.
      4. Because of defendants' act of plagiarism as described in paragraph 3, plaintiffs suffered gazillions of dollars of damages.

      WHEREFORE plaintiffs demand that the court give them gazillions of dollars from the scientists, and rename the universe "Space: The Final Frontier."
  • Shouldn't this read "Four scientists at Fermilab report..." rather than "Fermilab reports..."?

    Fermilab is a big organization. Saying that "Ferilab reports" implies that the whole organization reports this, and I'm absolutely positive that there are many people within Fermilab who would dispute these results/conjectures/hypotheses.

    Imagine someone reading something one of us says in a comment on /., and the NYT reporting that "Slashdot says that..."
  • by nimblebrain ( 683478 ) on Thursday March 24, 2005 @09:46PM (#12042049) Homepage Journal

    There's a decent amount of evidence that has been mounting over the past few years that a large component of redshift is in fact intrinsic, i.e. not attributed to the Doppler effect.

    In some ways, it seems related to the much-glossed-over "K Effect" of a few decades ago, where it was found that bright, bright blue stars seemed to be systematically redshifted.

    Researchers like M. B. Bell [eprints.org] are of the opinion that the intrinsic redshifts are superimposed on a Big Bang flow (reducing the actual velocity we should be measuring). Others, like Arp [britannica.com], believe that the Hubble Flow is an illusion, and that the universe is actually relatively static once you take away the intrinsic redshifts.

    David Russell's paper [lanl.gov] that just came out supports either view, and shows that other explanations (like Tully-Fisher Relationship errors or rotational velocities) are far too small to account for the large discrepancies.

    (Some more hubbub [physicsforums.com] on the topic.)

    In either case, intrinsic redshifts will take a lot of pressure off researchers to find 'dark energy', because the discrepancies of speed/distance are much reduced.

    Then, perhaps, we can stop looking for something that isn't there? :)

  • For anyone that can actually understand it click here [arxiv.org] (in pdf format)
  • I had not seen anyone raise this point, so I wanted to bring it up.

    With the vast amount of data at physicists fingertips, and many theories to test against this data set, how confident are physicists that the theories on which they base other theories are in fact true?

    How can we be sure that the data we receive from galaxies 10 billion light years away has not been diluted or compromised in a way we could not detect? If that happens, would not our theories then also be diluted or compromised and thus des
    • How can we be sure that the data we receive from galaxies 10 billion light years away has not been diluted or compromised in a way we could not detect?

      I don't know what you're thinking when you say "data ... diluted or compromised," but it's a lot more difficult than you may realize to come up with a scheme which has something funky happpening over long distances of space without us being able to detect side-effects.

  • preprint (Score:5, Informative)

    by bcrowell ( 177657 ) on Thursday March 24, 2005 @11:22PM (#12042659) Homepage
    The preprint is here [arxiv.org].

"What man has done, man can aspire to do." -- Jerry Pournelle, about space flight

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