The Big Bang

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The Big Bang

• The beginning of our universe as we know it

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A few questions to ponder

• What is the universe?
• What is the Big Bang Theory?
• What is a theory?
• How did it begin?
• Who came up with this idea?

Video Introduction http//www.youtube.com/watch?v
hSZqhqR5XKM
http//startswithabang.com/wp-content/uploads/2008
/05/bigbang.jpg
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What is the universe?

• Dictionary
• the totality of known or supposed objects and
  phenomena throughout space the cosmos
• a world or sphere in which something exists or
  prevails

(Colliding galaxies) http//www.thekeyboard.org.uk
/Antennae20galaxies.jpg
In other words? Everything we as humans know
exists
Background Photo Hubble Telescope picture of the
farthest known reaches of the universe http//heas
arc.gsfc.nasa.gov/docs/cosmic/gifs/cdfs_xray.jpg
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Known Universe

• When scientists talk about the size of the
  universe, they are talking about what we are able
  to observe. Based on their calculations, the
  visible universe is about 46.5 billion light
  years in any direction.

Jelly Bean Universe
http//chandra.harvard.edu/blog/files/images/jelly
.jpg
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What is this, Big Bang?

• The beginning of our expanding universe, which is
  still expanding. The Big Bang is an explanation
  for how and why our universe is expanding.

http//www.wildwildweather.com/forecastblog/wp-con
tent/uploads/2009/03/big_bang_wmap.jpg
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Universe Expanding

• The Big Bang occurred about 13.7 billion years
  ago, when the universe was very small, dense, and
  hot
• Since then, it has been cooling and expanding

http//www.scienzagiovane.unibo.it/darkmatter/imag
es/expanding-small.jpg
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The space we inhabit is itself expanding. There
was no center to this explosion it happened
everywhere. The density and pressure were the
same everywhere, so there was no pressure
difference to drive a conventional explosion.
Scientific American Misconceptions about the Big
Bang http//www.astro.princeton.edu/aes/AST105/Re
adings/misconceptionsBigBang.pdf
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But its just a theory

• A scientific theory is not something that is just
  plucked out of thin air. It is something that has
  been accepted by the scientific community as the
  best possible explanation for a phenomenon, after
  careful reasoning.

Toothpastefordinner.com
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Where did this idea come from?

• The origin of the Big Bang theory can be credited
  to Edwin Hubble, who made the observation that
  the universe is always expanding. He observed
  that a galaxys velocity is proportional to its
  distance. Galaxies that are twice as far from us
  move twice as fast, and that the universe is
  expanding in every direction.

http//www.wwu.edu/depts/skywise/cosmo/hubble.jpg
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Making our own Big Bang with balloons!
http//www.dark-cosmology.dk/tamarad/images/ballo
ons.jpg
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