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A mysterious, repulsive force

  1. Feb 21, 2004 #1
    http://www.msnbc.msn.com/id/4327735/

    "We still have almost no clue what it is," said study leader Adam Riess of the Space Telescope Science Institute (STScI) in Baltimore.

    Gravity is losing some unknown battle, cosmologists admit. They theorize that about 70 percent of the universe is made up of dark energy, while most of the rest is another mysterious thing called dark matter and only a small fraction is real matter like stars, planets and living entities.

    .....when Edwin Hubble discovered the expansion of the universe in the 1920s, Einstein called his cosmological constant his greatest blunder.

    =====

    are we moving too fast, jumpin to conclusions?

    am I an astronaut on the way to Mars, or only
    hallucinating in a dentist's chair......

    has 'reality' been debunked again?


    ------
    seems the article fell into a 'Black Hole'?....another msnbc glitch?----added xcerts below
     
    Last edited by a moderator: Feb 21, 2004
  2. jcsd
  3. Feb 21, 2004 #2

    Ivan Seeking

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    I wouldn't say that, but dark energy does appear to be real.

    ----Prof. Lawrence M. Krauss


    ----- Werner Karl Heisenberg and (approximately), Albert Einstein.
     
    Last edited: Feb 21, 2004
  4. Feb 21, 2004 #3

    Evo

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    One of my favorites:

    "The great tragedy of Science - the slaying of a beautiful hypothesis by an ugly fact."
    Thomas H. Huxley (1825 - 1895)
     
  5. Feb 21, 2004 #4
    here's a little more from the 'lost link' above.....

    Dark energy was conjured to explain a phenomenal discovery in 1998: Nearly all galaxies in the universe are receding from each other at an ever-faster pace.

    With the more recent finding that the expansion is accelerating, Einstein's idea was revived.
    The new findings support Einstein's cosmological constant, which modern cosmologists say implies that dark energy should not characteristically change over time. If that's right, the universe will continue to expand at an accelerating forever.
    The new results suggest that even if Einstein and modern dark energy theory are both wrong, dark energy will not destroy the universe for at least 30 billion years, Riess and his colleagues say.
    "Right now we're about twice as confident than before that Einstein's cosmological constant is real, or at least dark energy does not appear to be changing fast enough, if at all, to cause an end to the universe anytime soon," Riess said.

    Recent Hubble Space Telescope images of distant exploding stars add further confirmation to the permanence of a mysterious, repulsive force called dark energy that appears to dominate the universe.
    While scientists are not ready to close the case, they said today that dark energy, which is thought to permeate the cosmos and work in opposition to gravity, does appear to be a constant presence as predicted.
    The results bolster a theory that the universe won't end soon. But they leave researchers no more informed about the actual nature of dark energy.

    Albert Einstein was the first to consider something similar, which he called a cosmological constant. He said even the emptiest space would have some of this strange stuff in it.

    The universe is presently 13.7 billion years old.
    ====
    ((doesn't this depend on your time zone?-))

    anyway,
    Black holes, Dark Matter, Dark Energy.....wish they'd ask a poet to name this 'stuff'!!

    (if Black Holes are filled with light---why aren't they called 'light Holes' ?)
     
  6. Feb 23, 2004 #5
    Because They're black. They don't reflect any light, they absorb it, compact it, and make it into a tiny little singularity. No light sent out.

    White holes are predicted by a few theories, that they are the other end of a black hole, or that they happen in a 3 Dimensional brane when it collides with another roughly equal sized brane.

    They infinitely shoot light, matter, everything, away from them, until they evaporate.

    Of course, we don't know if they're real or not.
     
  7. Feb 23, 2004 #6

    Phobos

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    A good question...it's all so new. But the definition of "dark energy" remains vague...kind of an anti-gravity force that acts at cosmological (intergalactic) distances. Astronomers still have a long way to go before pinning it down.
     
  8. Feb 23, 2004 #7

    Phobos

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    Did you see the movie "Contact"? (scientist/astronaut laments not having a poet around to better describe the amazing sights)

    Anyway, those names are pretty good, IMO, given that this stuff is invisible & full of mystery. They certainly catch people's attention. Sometimes, the IAU (the folks who get to name all the asteroids, craters, stars, etc.) uses public input in their naming of stuff (I once submitted an entry for naming the craters on the asteroid Eros...not sure what the results of that contest were. )

    And why do we drive in a parkway and park in a driveway?
     
  9. Feb 23, 2004 #8
    Phobos:
    given that this stuff is invisible & full of mystery.
    -----
    trying to put all this together (as best my brane can do--which should be designated a "?-hole" (add a smily here for unknown-confusion), does it make any "sense" that there may be "beings" in any of this "darkness"?.....other 'dimensions' of possible 'existence'?
    Dark-matter 'entities'? or it's basicly 'gravity' .....i have some kind of 'primal-fear' of Black Holes....and the "dark energy" stuff doesn't help me sleep at night!.....direct me to a link for 'enlightment' !

    haven't seen "Contact"--seem to remember Armstrong got "One small step..." wrong.

    just curious-What was your crater's name suggestion?

    me/for Eros--Valentine Crater---Kisses---Milk Chocolate (for a "deep dark one"....
     
  10. Feb 25, 2004 #9

    Phobos

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    See? The names have whet your curiosity. :wink:
    As for your questions...well, I'll be interested to see future research results too. M-theory (string theory) has some interesting possibilities to it.

    Aw crud...memory fading...hmm...um...I think it was "Serenade" or "Serenading".
     
  11. Feb 26, 2004 #10
    It seems that 'spite of'
    'M-brane theory ((which is very close to meaning "in My-brain only theory"-or pretty darn 'imaginative-wild as UFOs'---Sign Post Up Ahead-- You're "breaking "The Speed Limit" Now!" kinda theories--))--(and i'm simply trying to 'clarify' the truely "strange" "Universe" we "live in" whether one is 'rational' or not! and i'm not sure how 'light-headed' i am-but 'things are really strange'))---

    And there seems to be an 'irrational' ,IMO, immediate 'rejection' of the idea that travelling vast distances (as we 'know them'),are 'insurmountable' due to the 'laws of Physics, so that the 'idea' of ET visits to Earth is incomprehensible to some (yet 'naively' surmountable by children-
    ie. maybe Santa's got 'twins'- and 'others' making full use of their imaginative faculities, and indeed 'rational' thinking that's 'out there' but wouldn't get you kicked out of the bed --being Science--for 'dreaming' up these wild theories. (( I'm lost in space ,right?....

    I must confess, in spite of using electricity everyday, reading about it, and talking to electricians
    (and a few are indeed my 'best friends'!), I still think it's just one of Santa's gifts-bottom line.

    (and I've been using the 'heat' produced by electric kilns since '75--even doing my own 'wireing'....yep, I rely on the 'theories' of my friends-always check first to see if there's been any 'new developements'--everything seems to be working ok--and then folks who work in ceramics ask me how i get these 'results'.....will take a long time to explain.)

    So i don't see have a problem with 'these problems' ,like the 'speed of light', or 'gravity' only working in one direction (or what ever)....I think human's and possibly 'machines' may solve all these problems in ways we cannot imagine at this time--
    man cannot fly....
    rather than 'breaking the speed of light', there may be simply a 'way around it'.....one guy at NASA came up with the 'hang-glider' and the rest is FUN!--even Leonardo de Vinci didn't get off the ground with his designs.

    If ET is here (big jump here of course) then obvioulsy we'll be able to ask him how it's done--but like me understanding electricity, maybe it won't make sense, but we can still go along for a ride.


    "just my imagination-running away with me"
    ====


    "Cracky--the Love Crater"

    yet another "crater's name suggestion"
     
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