9/12/2018 1 Burkey- ESS QUIZ Thursday At the instant of the Big Bang, all the matter, energy, time, & space in the Universe was condensed into a single, tiny point. We call this Singularity. Doppler Effect Occurs when the source of sound waves moves towards or away Sound moving TOWARDS Sound waves compressed Higher frequency Shorter wavelength Sound moving AWAY Sound waves stretched out Lower frequency Longer wavelength
7
Embed
Warm up 8.29 › uploads › 1 › 2 › 6 › 9 › ...9/12/2018 2 “Doppler Effect” with Light –is called Red Shift Red Shift This change of light to longer wavelength Light
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
II. In an instant, the universe expanded very quickly
III. Then it settled down to a slower rate of expansion,
cooling all the time
IV. After a few minutes it had cooled enough for
protons to form
Big Bang Theory (continued)
V. Hydrogen and helium were the raw ingredients
that were available for making stars
VI. Heavier elements were made inside stars dying
and exploding.
VII. Then newer stars created, many of them like our
solar system with abundance of complex
elements.
Evidence for Big Bang
**ALL was observational
“the four pillars of the Big
Bang theory“ the evidence to
support the theory.
9/12/2018
4
Evidence #1
The Universe is expanding
As the distance between galaxy clusters is
increasing today, it can be inferred that everything
was closer together in the past. *Red shifting by
Huble’s Law and a dark night sky.
What color is the sky at night?
DARK at night (Olber’s Paradox)
IF the universe were infinite in size, eternally old, and if stars shine all the time, then…
everywhere we look at night, we SHOULD see a star…but we DON’T.
the sky should be as bright as the Sun’s surface all of the time…but it’s NOT
We are surrounded by a cosmic particle horizon beyond which we can’t see.
Solution to Olber’s Paradox:
1. Much of the light is red-shifted
to the extent that the energy is
undetectable in the visible
spectrum..
2. Universe is not eternal. Light from
the most distant galaxies hasn’t had
time to reach us.
Will talk about the 4 pillars tomorrow.
9/12/2018
5
Edwin Hubble•Observed that nearly all galaxies are moving away from us with red shifting.
Therefore….The universe is expanding.
Hubble’s Law – from this guy!
1929
But, if all the galaxies are
moving away from us,
doesn’t that make us the
center of the universe???
Raisin Bread explains it all…
Cosmological Principle
From every galaxy, at
every time, the universe
looks the same in all
directions. Every galaxy
seems to be at the center
of the universe.
9/12/2018
6
Evidence #2
Cosmic Background Radiation
The bright intense light from the Big Bang - 13.7
billion years ago, still bathes the cosmos.
Space has a 2.7 Kelvin uniform background radiation temperature
•Wilson & Penzias at 1st thought it was background or “static” •It is believed to be microwave radiation left over from the Big Bang because it is isotropic (everywhere)