Big Bang and Black Holes: Topic Outline

What is important about the Big Bang And Black Holes topic?
I'd say it goes something like this...

1) "In the beginning..."

1.1) Singularity of infinitely small volume (and thus infinitely high temperature and pressure
1.2) This exploded/expanded - that event is the Big Bang itself

2) How do we know?

2.1) Hubble's Law - universe is expanding
2.1.1) Illustrated by Redshift [Light wavelength changes thanks to a stretching of the medium - space)
2.1.2) Extrapolate this backwards, and the universe would have been infinitely small at one point.

2.2) Cosmic background radiation
2.2.1) Remnants of the Big Bang explosion
2.2.2) Residual temperature in the universe of a few degrees Kelvin

2.2.3) Small temperature variations in this radiation - matter clumps; this clumping eventually aggregated itself into galaxies

3) What happened after the Big Bang?

3.1) Freeze-out of the "fundamental forces" - strong force, electromagnetic force, weak force, gravity [They used to be of equal strength, now they aren't - I just listed them in strongest-to-weakest order]

3.2) Inflationary Period
3.2.1) Especially rapid period of expansion in early universe (< 1 sec after BB)
3.2.2) Without it, the early universe would have had to have been relatively larg ein order to have reached the current size

3.2) Energy to Matter
3.2.1) E = M * C^2 : energy can be converted to matter...energy takes up less space than matter
3.2.2) Balance of matter annihilating antimatter, eventually regular matter won out
3.2.2.1) We don't know why regular matter won out

3.2.3) Big Bang Nucleosynthesis
3.2.3.1) Roughly 3min after BB. Occurred at temperature of 10^9 Kelvin
3.2.3.1) Particles coalesced into atoms
3.2.3.2) BBN only would have lasted long enough to form light elements.
Universe is made up of predominately light elements, this lending support to this important part of the Big Bang model
Various isotopes of hydrogen, helium, lithium and beryllium were formed

3.3) Later, stars and galaxies develop

4) The Cosmological Principle: important concept
4.1) Isotropic: Large-scale structure looks the same in all directions
4.2) Homogenous: General physical properties of the universe are the same everywhere in it
Thus, the universe has no edge and no center

5) What are galaxies?

5.1) The Formation of Galaxies
5.1.1) Galaxies formed about 1 billion years after big bang
5.1.2) Hierarchical merging [smaller-scale version of this process likely forms solar systems]

5.2) Different galaxy shapes

5.2.1) Spiral - a disk with spiral arms. Our own Milky Way is one. Relatively small nuclear bulge. Relatively large amounts of young stars and star formation.
5.2.2) Elliptical - Dominated by spheroid. Relatively old
5.2.3) Irregular and Peculiar - Those terms mean what you think they mean. :)

5.3) Galaxy relations: Galaxy clusters, superclusters

5.3.1) Galaxies do gather into clusters

5.3.2) Supercluster Types
5.3.2.1) Rich - >1000 galaxies, giant central galaxy
5.3.2.2) Poor - 10 to 1000 galaxies, more spirals
5.3.2.3) Isolated galaxies - even more likely to be spirals

5.3.2) Galaxies in superclusters not gravitationally bound to each other

6) What are black holes?
A superdense object, to the point where its gravity is so strong that not even electromagnetic radiation [light] can escape

6.1) Fuller explanation of black holes is provided by Einstein's theories of relativity

6.1.1) Spacetime - space and time are connected (they are *relative* to each other)
6.1.2) Gravity is dependent on spacetime
6.1.3) Special relativity predicts/explains unusual behavior that occurs with abnormal values of space, time, and/or gravity

6.2) Now, if no electromagnetic radiation, visible light or otherwise, emerges from a black hole, how do we study them?
6.2.1) Their effect on visible bodies near them: For ionstance, a black hole may suck in gas from nearby stars

6.3) Black holes are the Las Vegases of the universe - what happens [goes into] in a black hole stays in a black hole.
6.3.1) This is how black holes build mass
6.3.2) Difference: Actions in Las Vegas may also cause alimony, child support or prison time to increase

7) Dark Matter and Dark Energy: The Monkey Wrench in the Cosmological Works
We don't know what it is; hence the name 'dark'.
Nonbaryonic ("Baryons" are a type of particle with protons and neutrons being the most notable examples of them)

7.1) Composes most of the universe


7.2) Dark matter:
7.3) Dark energy: even more "weird" than dark matter

-More to come-