For Class Advanced Lab, Powerpoint on Dark Energy

1. Dark Energy by Jennifer Nalley March 2007

2. *About 70% of the calculated mass in the Universe can not be accounted for. *It has become apparent that something other than the matter and energy we know is responsible for the greater portion of the Universal contents. *Something else is out there, and it appears as though it is doing much more than simply filling up space. On to some history........

10. DARK ENERGY Current Beliefs and Theories Dark energy is responsible for about 70% of the density of the universe. It is gravitationally repulsive, fighting against the gravity of the mass in the universe (that should be causing the universe expansion to slow).It is believed to be the reason the universe expansion is accelerating. It does not cluster in galaxies like other matter. It appears to be spread smoothly. It, like dark matter seems to be unaffected by radiation. It has a uniform density- about 10 E-26 Kilograms per cubic meter. It reduces the rate at which other galaxies interact, merge, bang, overall gravitationally interact.

11. EINSTEIN! RIGHT AGAIN? Einstein's cosmological constant may have not been such a blunder after all Quoting SNLS- Super Nova Legacy Survey “ What is now being observed shows that this dark energy behaves like the discarded constant....to a precision of 10% Ph ysicist Leonard Susskind discusses the dark matter mystery at the American Association for the Advancement of Science meeting in Washington, D.C. Dan Falk MY BIGGEST BLUNDER!!! WAIT ONE MINIUTE!

12. Resources Scientific American- February 2007 “ The Universe's Invisible Hand ” by Christopher J. Conselice (SNLS) Super Nova Legacy Survey Argelander Institut f Ü r Astronomie The Cosmological Constant Problem May 12, 2000 by Steven Weinberg Physics World Magazine May 2004 University of Copenhagen's Dark Cosmology Center at the Niels Bohr Institute. (Info from web page).

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