Download static universe - St John Brebeuf

Origins of the Universe
http://www.pbs.org/wgbh/nova/universe/historysans.html
Types of Universe Models
1. Static Universe
2. Expanding (Inflation Theory) Universe
3. Oscillating Universe
Static Universe
http://en.wikipedia.org/wiki/Static_universe
A static universe, also referred to as a "stationary" or "Einstein" universe, is a
model in which space is neither expanding nor contracting. Albert Einstein proposed
such a model as his preferred cosmology in 1917[citation needed]. He added a positive
cosmological constant to his equations of general relativity to counteract the attractive
effects of gravity on ordinary matter, which would otherwise cause the universe to either
collapse or expand forever.
This motivation evaporated after the discovery by Edwin Hubble that the
universe is in fact not static, but expanding; in particular, Hubble discovered a
relationship between redshift and distance, which forms the basis for the modern
expansion paradigm. According to Gamow this led Einstein to declare this cosmological
model, and especially the introduction of the cosmological constant, his "biggest
blunder".[1]
Even after Hubble's observations, Fritz Zwicky proposed that a static universe
could still be viable if there was an alternative explanation of redshift due to a
mechanism that would cause light to lose energy as it traveled through space, a concept
that would come to be known as "tired light". However, subsequent cosmological
observations have shown that this model is not a viable alternative either, leading nearly
all astrophysicists to conclude that the static universe is not the correct model of our
universe.
The Big Bang Theory
•Until 100 years ago, scientists believed nothing ever changed in outer space.
The Big Bang Theory = everything in the universe came from a single starting point,
approximately 13.7 billion years ago.
Although there are other theories about the beginning of the universe, much scientific
evidence supports the Big Bang theory.
1. Evidence For The Big Bang Theory
1)Expanding Universe.
a) Using powerful telescopes, astronomers like
Edwin Hubble discovered many new celestial
bodies, and observed that everything in the
universe was moving further apart.
b) The universe expands like baking bread;
galaxies and other celestial objects are like
raisins in the dough, moving apart as the bread
bakes.
Horton Hears a Who:
Part 1
http://www.youtube.com/watch?v=B0qZ4V53EV4
Part 2 http://www.youtube.com/watch?v=3BsiN8SxUMM&feature=mfu_in_order&list=UL
c) Once astronomers realized everything was moving away from everything else,
they realized the universe might have originated from a single point.
2) Objects in the Universe are Red-Shifting
a)Light, like all forms of electromagnetic radiation, travels in waves. Objects in space give
off many different forms of radiation.
b)Like the sound of an ambulance siren changes as it passes you, light from stars exhibits
red-shift, indicating speed and direction of motion.
As the ambulance approaches,
the sound waves from its siren are
compressed towards the observer.
The intervals between waves
diminish, which translates into an
increase in frequency or pitch.
As the ambulance recedes, the
sound waves are stretched relative to
the observer, causing the siren's
pitch to decrease. By the change in
pitch of the siren, you can determine
if the ambulance is coming nearer or
speeding away.
If you could measure the rate
of change of pitch, you could also
estimate the ambulance's speed.
c) A spectroscope analyzes the unique spectrum of a star, which astronomers can
analyze to discover the direction and amount the light has shifted.
A red shift means the wavelength is
getting longer, and the star is moving
away from us.
Blue shift is the opposite; the star is
getting closer.
i) ROYGBIV. The red end of the visible spectrum is lower energy, while the blue end of the
spectrum is higher energy.
ii) Objects that approach us create higher energy waves, and therefore are seen in a blue
colour. Objects going away from us create lower energy waves, and are seen as red in colour.
a) Redshifting is the effect an object has that is moving away from us.
b) Blueshifting is the effect that an object has that is moving toward us.
c) Hubble discovered that all the stars were redshifting: moving away from us.
d) They also use it to talk about gravitational redshifting, as well as cosmological
redshifting, the idea that all objects in the universe is moving outward from a
single origin.
iii) This brings about the theory of the Big Bang- the theory that all matter in the universe is
moving outward, away from each other.
Scientists now apply the concept of the Doppler Effect for measuring all the other bands of the
electromagnetic spectrum- radio, microwave, infrared, ultraviolet, X-ray, and gamma rays.
https://www.youtube.com/watch?v=34sEX6VM9sU
Cosmic Background Radiation= the
energy left over from the Big Bang.
http://apod.nasa.gov/apod/ap050925.html
1.5 billion pixel image of the Andromeda Galaxy:
http://hubblesite.org/newscenter/archive/releases/2015/02/image/a/warn/
WMAP Resolves the Universe
This radiation was mapped by the COBE and WMAP explorations.
Credit: WMAP Science Team, NASA
Explanation: Analyses of a new high-resolution map of microwave
light emitted only 380,000 years after the Big Bang appear to
define our universe more precisely than ever before. The eagerly
awaited results announced last year from the orbiting Wilkinson
Microwave Anisotropy Probe resolve several long-standing
disagreements in cosmology rooted in less precise data.
Specifically, present analyses of above WMAP all-sky image
indicate that the universe is 13.7 billion years old (accurate to 1
percent), composed of 73 percent dark energy, 23 percent cold
dark matter, and only 4 percent atoms, is currently expanding at
the rate of 71 km/sec/Mpc (accurate to 5 percent), underwent
episodes of rapid expansion called inflation, and will expand
forever. Astronomers will likely research the foundations and
implications of these results for years to come.
(http://apod.nasa.gov/apod/ap050925.html)
http://curious.astro.cornell.edu/question.php?number=468
Oscillating Universe
One of the implications of the big-bang theory is that the universe will one day end, or at
least any life in the universe will come to an end. If the universe is either open or flat, meaning
that it expands forever, it will survive for an infinite period of time. But eventually all the
material in all the generations of stars will be exhausted and the universe will grow cold and
dark. In a closed universe, in which the expansion eventually stops and a contraction follows,
the end is far from cold and dark—as the Big Crunch approaches, the universe grows hotter and
brighter until it implodes into a singularity and gets crushed out of existence.
But is that what would really happen? Some scientists speculate that the Big Crunch would
not signal the end. Perhaps another Big Bang would follow the Big Crunch, giving rise to a new
universe of possibilities. The idea that Bangs follow Crunches in a never-ending cycle is known as
an oscillating universe. Though no theory has been developed to explain how this could ever
happen, it has a certain philosophical appeal to people who like the idea of a universe without
end.
http://www.pbs.org/wnet/hawking/universes/html/osci.html
Fate of the Universe
http://www.universetoday.com/37105/fate-of-the-universe/
by John Carl Villanueva on August 10, 2009
What is the ultimate fate of our universe? A Big Crunch? A Big Freeze? A Big Rip? or a Big Bounce? Measurements
made by WMAP or the Wilkinson Microwave Anisotropy Probe favor a Big Freeze. But until a deeper understanding of dark energy is
established, the other three still cannot be totally ignored.
Ever since scientists proved the Big Bang to be the most plausible cosmological theory, and since it only
focused more on how it might have all began, their attention started to shift to how the Universe would end. Thus, all 4
theories mentioned above (Big Crunch, Big Freeze, etc.) are actually offshoots of the Big Bang.
The Big Crunch predicts that, after having expanded to its maximum size, the Universe will finally collapse
into itself to form the greatest black hole ever.
On the opposite side of the coin, the Big Freeze foretells of a universe that will continue to stretch forever,
distributing heat evenly in the process until none is left to be usable enough. Hence, it is also known as the Heat Death.
A more dramatic version of the Big Freeze is the Big Rip. In this scenario, the Universe’s rate of expansion
will increase substantially so that everything in it, down to the smallest atom, will be ripped apart.
In a cyclic or oscillatory model of the Universe, there will be no end … for matter and energy, that is. But for
us and the Universe that we know of, there will definitely be a conclusion. In an oscillatory model, the Big Bang and Big
Crunch form a pair known as the Big Bounce. Essentially, such a universe would simply expand and contract (or bounce)
forever.
For astronomers to determine what the ultimate fate of the Universe should be, they would need to know
certain information. Its density is supposedly one of the most telling.
You see, if its density is found to be less than the critical density, then only a Big Freeze or a Big Rip would
be possible. On the other hand, if it is greater than the said critical value, then a Big Crunch or Big Bounce would most
likely ensue.
The most accurate measurements on the cosmic microwave background radiation (CMBR), which is also the
most persuasive evidence of the Big Bang, shows a universe having a density virtually equal to the critical density. The
measurements also exhibit the characteristics of a flat universe. Right now, it looks like all gathered data indicate that a
Big Crunch or a Big Bounce is highly unlikely to occur.
To render finality to these findings however, scientists will need to know the exact behavior of dark energy. Is
its strength increasing? Is it diminishing? Is it constant? Only by answering these will they know the ultimate fate of the
Universe.
We’ve got a few articles that touch on the fate the universe here in Universe Today. Here are two of them:
No “Big Rip” in our Future: Chandra Provides Insights Into Dark Energy End of the Universe
NASA also has some more: The Life and Death of Stars
What is the Ultimate Fate of the Universe