Echoes of the Big Bang • If there is repulsive stuff in the universe than the current rate of expansion could be larger than it was years ago because this dark energy has made space push apart • Lambda – over a big enough distance it pushes stuff apart o thought up by Einstein to compensate for the idea of static universe o Over great distances the forces the universe to expand • Several billion years after the big bang the universe’s expansion began to slow down, but then went through a “jerk” and started accelerating • The universe will expand forever – unless the currently repulsive energy becomes attractive in the future • The Universe can closed (finite), but it will still expand forever – unless it starts decelerating in the future • Age of the Universe = 14 billion years o consistent with globular cluster ages • OmegaM – OmegaLambda = -0.4 • OmegaLambda = .7 –implicates a long rang repulsive effect (cosmic antigravity) o vacuum has a non-zero repulsive energy (dark energy)
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 04/04/2008 for the course ASTRO C 10 taught by Professor Filippenko during the Fall '08 term at University of California, Berkeley.