Dark energy overtaking gravity

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Dark energy overtaking gravity

  • Expansion of the universe began accelerating 5 or 6 billion years ago. I'm wondering if this was when the repulsive force of dark energy overtook the mutual gravitational attraction of galaxies (when the universe got large enough). I'm wondering if the repulsive force of dark energy INCREASES with distance, where gravity DECREASES with distance.



    [edited by: Jim Hartsell at 09:13 PM (GMT -6) on Aug 09, 2010]

    "Time is nature's way of keeping everything from happening at once." - Woody Allen

  • Are you suggesting the the mathematical "inverse square law" is violated by dark energy?  Or that the gravitational "constant" is not necessarily a constant value?

    ---Poppa Chris---

    "Second star to the right - Then straight on until morning!" - Peter Pan

    Celestron CPC1100GPS (XLT) - 279mm aperature, 2800mm Focal length. (f10) Celestron Ultima LX (70deg AFOV) Eyepieces 32mm thru 5mm, Canon EOS Rebel T2i DSLR, Orion Star Shoot Planetary Imager IV, Celestron Skymaster 15x70 binoculars

  • How about an inverse of the inverse square law for the negative pressure of dark energy? This would support my thought, where the repulsive force increases with distance.



    [edited by: Jim Hartsell at 07:23 PM (GMT -6) on Aug 10, 2010]

    "Time is nature's way of keeping everything from happening at once." - Woody Allen

  • Jim Hartsell

    How about an inverse of the inverse square law for the negative pressure of dark energy? This would support my thought, where the repulsive force increases with distance.

    Interesting thought but not real logical, the inverse of the inverse is the original  - therfore you would square the unit of force for every unit of distance.  Forces would become so incomprehensibly huge in such a very short distance that the universe could not exist at all. 

    ---Poppa Chris---

    "Second star to the right - Then straight on until morning!" - Peter Pan

    Celestron CPC1100GPS (XLT) - 279mm aperature, 2800mm Focal length. (f10) Celestron Ultima LX (70deg AFOV) Eyepieces 32mm thru 5mm, Canon EOS Rebel T2i DSLR, Orion Star Shoot Planetary Imager IV, Celestron Skymaster 15x70 binoculars

  • I should have said REVERSE Inverse Square Law, if you can imagine what that would be. It may not involve the Inverse Square Law at all. It could be a relativistic thing. If I could explain it in the detail you want, I'd be writing a feature article in Astronomy magazine. But yes, it would violate the Inverse Square Law.

    Do you believe the universe is expanding? That the expansion began accelerating after a period of time?

    "Time is nature's way of keeping everything from happening at once." - Woody Allen

  • Jim Hartsell

    Expansion of the universe began accelerating 5 or 6 billion years ago. I'm wondering if this was when the repulsive force of dark energy overtook the mutual gravitational attraction of galaxies (when the universe got large enough). I'm wondering if the repulsive force of dark energy INCREASES with distance, where gravity DECREASES with distance.

    Jim, 

    That is exactly what some cosmologists believe.  The repulsive force of dark energy grows in strength as cosmological expansion increases.

    http://www.universetoday.com/11933/has-dark-energy-always-been-constant/

    Dave Mitsky

     

    Chance favors the prepared mind.

    Fere libenter homines id quod volunt credunt.

    A man is a small thing, and the night is very large and full of wonders.

  • Dave,

    Thanks for your reply and the link. For the overtaking part, I just found the 2007 link

    http://www.redorbit.com/news/science/1085903/mysterious_dark_energy_winning_cosmic_tug_of_war/index.html,

    which says

    "But in the last 5 billion years, dark energy - a sort of "negative gravity" or "repulsive" force - has overcome gravity and is driving galaxies apart at an ever-increasing rate."

    This again implies that the repulsive force of dark matter does indeed increase with distance.

    I'm three years too late, so I quess they won't be calling it "The Hartsell Effect".



    [edited by: Jim Hartsell at 08:56 PM (GMT -6) on Aug 17, 2010]

    "Time is nature's way of keeping everything from happening at once." - Woody Allen