Nov. 25 – 2B03 25/11/2011 10:28:00 AM
Material after mid term weighted a little more heavily.
Merger of Bullet cluster
Galactic cannabilism (eating of small galaxies by big galaxies) - classic
example happening in the milky way.
Lot of mass in the dark matter halo.
Milky way ripping away dwarfs
Bullet Cluster - 2 clusters colliding.
As they collide, we can separate parts of the galaxy
Collionless vs, collioning
Structure in the Universe
Even though black holes relatively small, it can affect the whole
galaxy around it.
Are there things bigger than galaxy clusters?
o Reason she stops at galaxy clusters – the largest
gravitationally BOUND systems. Stable system.
o There are structures on larger scales but are not
Superclusters, Walls, and Voids.
Position plot of stars in the nearby universe. Distribution is not
perfectly uniform. Clearly some overdensities and places where no
galaxies at all.
Galaxies clump into big scales
Walls – where there is a lot of galaxies
Voids – devoid of galaxies
As you move away of origin, you can only see the brigher ones.
o On small scales, big fluctuations – wall or void
o On bigger scales, looks uniform though.
Brief History of our Universe
CBT – baby pic of universe. o Fluctuations already in place.
o SOmething happened right after Big Bang that set up