Hiromi Suenaga Cody Tamura Period 1

 It affects the Universe’s expansion  Other than that it is a total mystery  Roughly 70 % of the universe is dark energy

 It could be a property of space  Albert Einstein was the first person to realize empty space is not really empty

 One of his Gravity Theories that uses a cosmological constant makes a prediction that “empty space” can possess its own energy

 As more space comes into existence, more dark energy would appear  This would accelerate the expansion of the Universe  No one really understands why the cosmological constant is there

 Another theory utilizes the quantum theory of matter  Empty space is comprised of “virtual” particles that form and disappear continuously  Unfortunately, physicists tried to calculate the energy empty space would have, but was the solution was 10^120 times too large

 Another theory is that dark energy could be a new kind of dynamical energy fluid or field  Another theory is that Einstein’s theory is incorrect  Dark energy would not only affect the expansion of the Universe, but would also affect normal matter in galaxies as well.

 Before the dark energy was first observed, there were two models of the fate of the Universe

 The Big Crunch theorizes that the Universe’s expansion would slow down until it finally begins to retract  Essentially, it would be the opposite of the Big Bang

 The Big Chill theorizes that the Universe would expand at a decelerating rate  Galaxies would drift extremely far apart from each other  All stars would die out and the Universe would be vast, cold, and dark

 With dark energy, the Universe’s expansion would accelerate until clusters of galaxies would tear apart  Galaxies would tear apart, until molecules and atoms would rip apart  It would be a more violent expansion than the Big Bang

 The Chandra X-ray Observatory has found evidence that the Big Rip is not in the Universe’s future  Observations have shown an increase in mass in galaxy clusters  An increase in mass or growth would be difficult with dark energy  Observations strengthen the idea that dark energy is the cosmological constant in Einstein’s theory

 OR8 OR8

 Atkinson, Nancy. "No “Big Rip” in Our Future: Chandra Provides Insights Into Dark Energy." Universe Today. 16 Dec Web. 17 Apr  "Dark Energy." Large Synoptic Survey Telescope. Web. 17 Apr  "Dark Energy, Dark Matter." NASA Science. Web. 17 Apr  "HubbleSite - Dark Energy - Fate of the Universe." HubbleSite - Out of the Ordinary...out of This World. Web. 17 Apr  Moskowitz, Clara. "What Is Dark Energy? | Space.com." Space, NASA Information & News | Outer Space Flight Videos & Pictures | Astronomy, Solar System Images | Space.com. Web. 17 Apr