Big Bang Theory PowerPoint - rajhans95.files.wordpress.com · Grand Unification Epoch Electroweak...
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Big Bang Theory PowerPoint
Transcript of Big Bang Theory PowerPoint - rajhans95.files.wordpress.com · Grand Unification Epoch Electroweak...
Big Bang
Theory
PowerPoint
Grand Unification Epoch
Electroweak Epoch
Inflationary Epoch
Quark Epoch
Hadron Epoch
Hadron Epoch
Photon Epoch
Big Bang Nucleosynthesis
Recombination
The Primordial Era
Name: ______________ # ____ Period: 1 2 3 4 5 6
Left is late
Right on time
Big Bang Theory
Color Code by Time
• Grand Unification Epoch
• Inflationary Epoch
• Electroweak Epoch
• Quark Epoch
• Hadron Epoch
• Lepton Epoch
• Photon Epoch
Grand Unification Epoch
Electroweak Epoch
Inflationary Epoch
Quark Epoch
Hadron Epoch
Hadron Epoch
Photon Epoch
Big Bang Nucleosynthesis
Recombination
The Primordial Era
Name: ______________ # ____ Period: 1 2 3 4 5 6
Left is late
Right on time
Big Bang Theory
What is a Theory?
• A Theory is a system of rules and principles that can be applied to different circumstances. Usually there is evidence which suggests that a theory is true.
What is a Theory?
• A Natural Law is a theory that
has been refined, tested, and
confirmed.
• A Theory is only good until
additional evidence
• disproves it.
What is the Big Bang?
• The Big Bang Theory is the dominant scientific theory about the origin
of the universe.
What is the Big Bang?
• According to the Big Bang, the universe was created
sometime between 10 billion and 20 billion years ago from
a cosmic explosion that hurled matter in all
directions.
What is the Big Bang?
•Our best
understanding is
•13.7
•billion years old.
Who first proposed the Big
Bang?
• In 1927, the Belgian priest Georges Lemaître was the first to propose that the universe began with
the explosion of a primeval atom.
Georges Lemaître
Who first proposed the Big Bang?
• Lemaître’s proposal came after observing the red shift in distant
nebulas by astronomers.
Red Shift
•Red shift
• indicates objects
moving away from
•an observer.
Red Shift
• Wavelengths are longer,
• moved towards the red part of the spectrum
Red Shift
Blue Shift
•Blue shift
• indicates objects
moving towards
•an observer.
Blue Shift
• Blueshift
• Wavelengths are shorter,
• moved towards the blue part of the
spectrum
Blue Shift
• Blueshift
• Wavelengths are shorter,
• moved towards the blue part of the spectrum
Blue Shift
Evidence for the Big Bang
• In 1929,
• Edwin Hubble
• found experimental evidence
to help justify Lemaître's
theory and confirm the
redshifts.
Edwin Hubble
Evidence for the Big Bang
• He found that distant galaxies in every direction are going away from us with speeds proportional
to their distance.
Evidence for the Big Bang
• Galaxies are vast collections of stars.
Galaxies like the Milky Way have hundreds of
billions of stars.
Evidence for the Big Bang
• Some galaxies have
trillions of stars while
others have only a few
million stars.
Whirlpool Galaxy
What does this mean?
• This means that the
closer Galaxies are
moving away from us
slowly.
What does this mean?
• The farther Galaxies
are moving away faster
yet.
What does this mean?
• This means that the closer Galaxies are moving away from us slowly.
• The farther Galaxies are moving away faster yet.
Expanding Raisins
• Galaxies in the Universe are like raisin bread, the close ones only move a little when baked.
Expanding Raisins
• When the bread bakes, the
far raisins move the most.
•http://map.gsfc.nasa.gov/ContentMe
dia/990404b.gif
Hubble’s Law Tests of the Big Bang: Expansion •This simple ratio
between the distance
and the speed of
galaxies moving away
from each other, set forth in 1929,
This ratio Tests of the Big Bang: Expansion
•is now known as
Hubble’s law.
•It shows that the
universe is expanding.
Distance vs. Velocity
Hubble’s Law
Origin of the term Big Bang
•The term "Big Bang" was coined in 1949
by Fred Hoyle during a BBC radio program,
Foundations of the Big Bang Model
Foundations of the Big Bang Model
Foundations of the Big Bang Model
• The first key idea dates to 1916
when Einstein developed his
• General Theory of Relativity
which he proposed as a new
theory of gravity.
Foundations of the Big Bang Model
• His theory generalizes Isaac Newton's original theory of gravity, c. 1680, in that it is supposed to be valid for bodies in motion as well as bodies at rest. Newton's gravity is only valid for bodies at rest or moving very slowly compared to the speed of light (usually not too restrictive an assumption!).
Foundations of the Big Bang Model
• A key concept of General Relativity is that gravity is no longer described by a
gravitational "field" but rather it is supposed to be a distortion of space
and time itself. Physicist John Wheeler put it well when he said "Matter tells
space how to curve, and space tells matter how to move."
Foundations of the Big Bang Model
• Originally, the theory was able to account for peculiarities in the
orbit of Mercury and the bending of light by the Sun, both
unexplained in Isaac Newton's theory of gravity. In recent years, the theory has passed a series of
rigorous tests.
Foundations of the Big Bang Model
• After the introduction of General
Relativity a number of scientists,
including Einstein, tried to apply the
new gravitational dynamics to the
universe as a whole. At the time this
required an assumption about how the
matter in the universe was distributed.
Foundations of the Big Bang Model
• The simplest assumption to make is that if you viewed the contents of the universe with sufficiently poor vision, it would appear roughly the same everywhere and in every direction.
Foundations of the Big Bang Model
• That is, the matter in the
universe is homogeneous and
isotropic when averaged over
very large scales.
Foundations of the Big Bang Model
• This is called the
Cosmological Principle.
• This assumption is being tested continuously as we actually observe the distribution of galaxies on ever larger scales..
Foundations of the Big Bang Model
• The following picture shows
how uniform the distribution
of measured galaxies is over a
30° swath of the sky.
Foundations of the Big Bang Model
• In addition the
• cosmic microwave background radiation,
• which is the leftover heat from
• the Big Bang is called the CMB.
Foundations of the Big Bang Model
• CMB has a temperature which is highly uniform over the entire sky. This fact strongly supports the notion that the gas which emitted this radiation long ago was very uniformly distributed.
Foundations of the Big Bang Model
• General Relativity and Cosmological Principle
• These two ideas form the entire theoretical basis for Big Bang cosmology and lead to very specific predictions for observable properties of the universe.
Tests of Big Bang Cosmology
•Expansion
•The Light Elements
•The CMB
Confirmation of the Theory
• The Big Bang Theory received its strongest confirmation when the cosmic background radiation was discovered in 1964 by Arno
Penzias and Robert Wilson.
Confirmation of the Theory
• Arno Penzias and Robert Wilson, later
won the Nobel Prize for this discovery.
Penzias and Wilson
• Arno Penzias and Robert
Wilson in front of the Bell
Laboratories Radio Telescope.
• Click the picture to hear the sound.
Background Radiation
• Penzias and Wilson found radio signals in all areas of the sky.
• These radio signals have a hissing sound.
• The radio waves are at a temperature of 3 degrees above absolute zero.
Support for the Theory
• The big bang was initially suggested because it explains why distant galaxies are traveling away from us at great
speeds.
Support for the Theory
• The theory also predicts the existence of cosmic
background radiation (the glow left over from the
explosion itself).
Cosmic Background Radiation
• The Cosmic Background Radiation is microwave radiation found in all parts of the sky.
Cosmic Background Radiation
• The color
changes are due
to only
0.1 degrees of
temperature
difference.
What Does This Mean?
• If all the Galaxies are moving away from us, are we at the center of
the Universe?
What Does This Mean?
• No, if we could be on another galaxy we would
see the same thing, everything would be
moving away from that galaxy.
The Center?
• This means that all matter seen in the Universe was formed at the same time, at the same place, in the center of the Universe.
The Center?
• Everything can be
considered to be at the
center of the Universe,
according to your
perspective.
Reversing Time
• Astronomers have taken all the Galaxies and moved them backward in time to the point when they would have come from the same point.
Reversing Time
•This point is called a
singularity.
What was it like?
• Astrophysicists do not know the proper physics
to describe the beginning exactly, but
have some ideas.
What was it like?
• At one – ten millionth of a second, the
temperature of the Universe was very hot,
over
• 1 Trillion degrees.
WMAP has produced a new, more detailed picture of the infant universe. Colors indicate "warmer" (red) and "cooler" (blue) spots. The white bars show the "polarization" direction of
the oldest light. This new information helps to pinpoint when the first stars formed and provides new clues about events that transpired in the first trillionth of a second of the universe.
WMAP has produced a new, more detailed picture of the infant universe. Colors indicate "warmer" (red) and "cooler" (blue) spots. The white bars show the "polarization" direction of
the oldest light. This new information helps to pinpoint when the first stars formed and provides new clues about events that transpired in the first trillionth of a second of the universe.
Density of the Beginning
• The density was estimated to have been
more than 5 x 1013 grams per cubic
centimeter.
Density of the Beginning
• This matter was high-energy photons.
• According to Einstein’s Theory, energy can convert to matter.
Matter in the Universe
• As energy converted to matter, antimatter was also
created.
• This antimatter and matter collided, giving back energy to the system.
Matter in the Universe
• As the Universe continued to expand,
the temperature cooled.
4 Seconds of Time
•After 4 seconds of time, the Universe had cooled
enough for electrons, protons, and neutrons to
form.
30 Minutes of Time
• By the time the Universe was 30 minutes old it had
cooled sufficiently that nuclear reactions had
combined to form elements.
30 Minutes of Time
•25 % helium
75 % hydrogen
30 Minutes of Time
•25 % helium
75 % hydrogen
300,000 years
• At 379,000 years
• from the Big Bang,
• the Universe had cooled enough for it to become
transparent and light could escape.
• Before this time, no light could escape.
300,000 years
• The temperature had
reached 3,000
degrees.
Dark Age
• As the Universe
continued to expand, the
glow of the Big Bang
had faded so it became
dark.
Dark Age
• Eventually, matter coalesced from nebulas of dust and gas to form
stars.
• These stars had no metals in them.
First Stars
• The first stars formed with the ratio of 75% hydrogen
and 25% helium.
• These were massive stars and were very unstable and
lived for a short time.
First Stars
• These were massive stars
and were very unstable and
lived for a short time, before
exploding in extreme
violence as a supernova
explosion.
First Stars
• These massive stars
exploded giving rise to
more massive elements,
such as oxygen, nitrogen,
iron, and uranium.
Element Abundance (% of
total Abundance
number of atoms) (% of total mass)
Hydrogen 91.2 71.0
Helium 8.7 27.1
Oxygen 0.078 0.97
Carbon 0.043 0.40
Nitrogen 0.0088 0.096
Silicon 0.0045 0.099
Magnesium 0.0038 0.076
Neon 0.0035 0.058
Iron 0.030 0.014
Sulfur 0.015 0.040
Birth of Black Holes
• As Galaxies formed, the
first massive stars
formed in the center of
the Galaxy where most
of the matter was found.
Birth of Black Holes
• When these massive
stars exploded they
formed Black Holes.
• We see evidence of
these Black Holes in the
first Galaxies.
Black Holes
•As matter
gets
sucked
into the
Black Hole,
energy
leaves as a
jet at the
poles.
Is all matter light, such as
hydrogen and helium?
• Our Solar System has a lot of
heavier elements, such as
iron and uranium. These
elements were not found in
the early Universe.
Is all matter light, such as
hydrogen and helium?
• It has been suggested that the matter for our solar
system is 3rd generation, meaning it has been a part of at least 2 other stars which
have exploded.
Star Dust
• Heavy elements can
only be made from
the explosion of
massive stars.
Star Dust
• Due to the fact that our bodies are made of
heavier elements, such as iron in our blood, we can say that humans are
made of Star Dust.
Accelerating Universe
• When we look into the
depths of space, we see a
myriad number of galaxies,
all moving away from us.
Accelerating Universe
• These galaxies are accelerating. This
means they are going faster and faster.
What Causes This Acceleration?
•Something must be
causing the Universe to
go faster.
What Causes This Acceleration?
• Dark Matter and Dark
Energy are suggested to
be causing this
acceleration.
The Visible Universe
• The dark energy is the
push that causes our
Universe to accelerate
outward.
The Visible Universe
• is only
•4% visible matter,
• dark matter about 30%, and
dark energy about 66%.
Will the Universe keep
expanding?
• Astronomers think with the amount of matter found in
the Universe, that the Universe will keep
accelerating and expanding forever outward.
What will happen to the
Universe?
• As the Universe continues to expand, the
stars and galaxies will become farther away
and more difficult to see.
What will happen to the
Universe?
• Eventually, all the stars and galaxies that we
currently see will slowly burn out leaving the
Universe dark and cold.
• The Hubble
Deep Field
picture
shows
thousands of
galaxies,
some at the
beginning of
their
formation.
• The
Hubble
Ultra Deep
Field
picture
shows
thousands
of
galaxies,
some at
the
beginning
of their
formation.
What is the End?
• This is the end of our powerpoint.
• The end of the universe will look like this……
Photon Epoch
Dark Ages
Stelliferous Era
Degenerate Era
BlackHole Era
The Dark Era
Photon Epoch
Dark Ages
Stelliferous Era
Degenerate Era
BlackHole Era
The Dark Era
Color Code by Time
• Grand Unification Epoch
• Inflationary Epoch
• Electroweak Epoch
• Quark Epoch
• Hadron Epoch
• Lepton Epoch
• Photon Epoch
