Download Formation of the Universe

Formation of the Universe
What is the universe?
Universe­ everything that exists, all matter and
energy everywhere
Why is it there and where did it come from?
scientists can never answer this!
How did it form?­ There is a theory for this...
BIG BANG THEORY
The Big Bang Theory is the most widely accepted scientific theory for the
origin of the universe.
The Big Bang Theory states that:
The universe began about 14 billion
years ago as an extremely hot, dense
and compact state (singularity) that
underwent an extremely violent
expansion.
The universe is still expanding today
What does "singularity" mean?
The singularity didn't appear in space; rather, space began inside
of the singularity. Prior to the singularity, nothing existed, not
space, time, matter, or energy ­ nothing. So where and in what
did the singularity appear if not in space? We don't know. We
don't know where it came from, why it's here, or even where it is.
All we really know is that we are inside of it and at one time it
didn't exist and neither did we.
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What is beyond the expansion?
Nothing is beyond the expansion­ space curves and if
you go the edge you will end up back at the start!
How do we know that this theory is true?
Evidence for the Big Bang Theory
There are two main pieces of evidence for the Big Bang Theory:
1. Movement of Galaxies
­ Galaxies are giant star/matter clusters
­ In 1929 Edwin Hubble discovered that the galaxies that are farthest
from us are moving the fastest away from us
­ This suggests that the universe originated from a single point
Diagram ­ runners in a race as an analogy to explain galaxy movement
­ if all runners start the race at the same point, then the faster runner
would always be ahead of the slower runner. If runners started at
different points (ie. a slower runner having a head start) then a slower
runner could be ahead of a faster one
­ like the runners, if the galaxies started at one point then the fastest
moving galaxies should be the farthest from us which is what we see
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2. Cosmic Microwave Background Radiation
­ In 1965 two scientists named Penzias and Wilson
discovered a Cosmic Microwave Background
radiation (CMB) which is everywhere in the
observable universe
­ This radiation is thought to be the remnant of
radiation from the Big Bang therefore providing
evidence that it occurred
The Big Bang Theory Timeline
Use page 509 in Sciencepower to help you complete the following chart
Temperature Substance Formed Time 10­43 seconds 1032 oC
____
10­4 seconds
cooling cooling Protons and neutrons
Helium cooling Helium STOPS 3000 oC
____
1 billion years
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