1. Notes 30.4 The Big Bang Theory
Std 2g: How the red-shift provide evidence for the “big bang” model that suggests that the universe has been expanding for billion years
Objective 1: Explain how Hubble’s discoveries lead to an understanding that the universe is expanding
Objective 2: Summarize the big bang theory

2. Cosmology - the study of the origin, structure and future of the universe
Scientists study the light given off by an entire galaxy
They create the spectrum for the galaxy which gives us info about our universe

3. Hubble’s Observations
Hubble found that the spectra of most galaxies shifted toward the red end of the spectra
Except a few closest to Earth

4. The Expanding Universe
Moving away from Earth
The faster the galaxy, the faster they are moving
The Red Shift = the universe is expanding (getting bigger and bigger)

5. Objective 1: Explain how Hubble’s discoveries lead to an understanding that the universe is expanding
What is the study of the origin of the universe?
Cosmology
What is did Hubble discover about the color of galaxies?
They shifted toward the red end of the spectra
What does a red shift in galaxies mean for the universe?
It is expanding

6. The Big Bang Emerges
The Big Bang theory – the theory that all matter and energy in the universe was compressed into an extremely small volume that 13 to 15 billion years ago exploded and began to expanding in all directions

7. Evidence for the Big Bang Theory
Red shift of distant galaxies – shows universe is expanding
Cosmic Microwave Background Radiation (1965) low levels of energy evenly distributed throughout the universe were discovered; considered a remnant of the big bang
Ripples in space – indicate the first stages in the formation of the universe’s 1st galaxy

8. Cosmic Microwave Background Radiation (CMBR)
It formed shortly after the big bang
Now, the energy of the background radiation is 3⁰C above absolute zero ( ⁰C), which is the coldest temp possible
(Background of this slide show is a picture of CMBR)

9. Ripples in Space
Map of temperature differences reveals interesting information
Ripples are irregularities in the CMBR caused by small fluctuations in matter distribution
Ripples hold the clues to how the early universe evolved
Video-Super clusters of galaxies

10. Dark Matter
Dark Matter- 23% of the universe is made up of matter that does not give off light
4% of universe is made of the elements we know to exist

11. Dark Energy
Dark Energy- most of the universe is composed of something we don’t know anything about (73%)
Acts as a force that opposes gravity
dark energy in pushing galaxies apart

12. Objective 2: Summarize the Big Bang theory
What are the 3 pieces of evidence for the Big Bang Theory?
Red shift, CMBR and ripples in space
What do scientist think the ripples will reveal?
How the early universe evolved
What do scientist think is pushing the galaxies apart?
Dark energy