Test 2, 19 Novewmber 2014 <br>
Astronomy 123</br>
<p>
World Views of the
Universe (Chapters 26), 
History of the Universe (Chapters 26 and 
27), Observations and the Fate of the Universe (Chapters 24-26) 
<p><hr><p>
Old tests:
<p>
<a href="http://pages.uoregon.edu/~imamura/123cs/exams/astr123_x1.pdf">Test 1</a>, 
<a href="http://pages.uoregon.edu/~imamura/123cs/exams/astr123_x2_fall2011.pdf">Test 2</a><p>
<ul>
<li>Black Holes and Gravity:
<ul>
<li>There is a supermassive black hole at the center of the Milky Way galaxy. 
What is a black hole? What are the properties of nonrotating black holes
(Schwarzschild black holes)?
What is Cosmic Censorship? What is Hawking radiation?
<li>Sketch the structure of a black hole.
What are the parts of a nonrotating black hole
(Schwarzschild Black Hole): the Event Horizon, 
the singularity, the Schwarzschile radius?
<li>Contrast space and time outside the Event Horizon to inside the Event
Horizon of a Schwarzshild black hole. 
<li>Why do objects cluster in the Universe?
Can we
reconcile the observed structure of the Universe with the CMBR? Explain your
answer.
<li>How does the observed structure of the Universe help to determine how much
exotic dark matter compared to normal matter must exist in the Universe?
</ul>
<p><hr><p>
Models for the Universe
<ul>
<li>How can we distinguish open, closed, and flat universes? Describe the tests
and the results of the tests described in class. Describe the behavior of 
parallel lines, triangles in the different Friedman models. What astronomical
objects have been used to perform these tests?
<li>What topological tests can we apply to determine the type of universe 
it is in which we live? What do we mean by topological test?
<li>What other class of test has been used to determine the type of universe 
it is which we live? Describe these tests.
<li>Describe the observation which gave the first credible evidence that
the expansion rate of the Universe is increasing with time. What important
result follows from the increasing expansion rate of the Universe?
</ul>
<p>
History of the Universe
<p>
<ul>
<li>How old is the Universe? How can we estimate the age of the Universe? 
How old are the oldest
stars in the galaxy? (What objects are we referring to?
Is there a problem with this age for the oldest stars?
<li>Sketch Hubble <i>Law</i> for nearby galaxies. Indicate how the
Hubble <i>Law</i> changes for universes which are speeding up, slowing 
down, closed universes, open universes.
</ul><p>
<ul>
<li>Describe the Horizon Problem. Include the observations upon which the 
problem" is based, include why the observation leads to the "problem." 
<li>Describe the Flatness Problem. Include the observations upon which the 
problem" is based, include why the observation leads to the "problem." 
<li>Describe the Anti-Matter/Matter Asymmetry Problem. 
Include the observations upon which the 
problem" is based, include why the observation leads to the "problem." 
<li>Describe the Cosmological Constant Problem. 
Include the observations upon which the 
problem" is based, include why the observation leads to the "problem." 
</ul>
<p><hr><p>
Dark Energy and Anti-Matter: What is anti-matter? How do the properties of 
the anti-matter electron, the position, differ from the matter electron? 
<p><hr><p>
History of the Universe<p>
<ul>
<li>Describe and outline the general history for the evolution of the Universe.
<ul>
<li>List the phases in the evolution of the Universe
<li>Give the time at which the phases set in
<li>Give the basic events which occur during the phases
<li>What (events) mark the transitions between the phases
</ul>
<li>What are the four known forces of the current Universe? Have there always
been only four distinct forces (four distinct ways in which things
interact) in the Universe? If not, how has the situation evolved?
<li>What forces play dominant roles in
the evolution of the Universe? How does the changing number of forces 
as the Universe evolves lead to <i>inflation</i>?  
<li>What is meant by the terms GUT and Planck era?
<li>Describe <i>Inflation</i>. Describe how inflation is related to GUTs. How
can we understand inflation through analogy with ordinary phase transitions
such as occur for water as it goes from liquid to solid (ice), liquid to gas
(evaportation), solid to gas (sublimation) as the temperature is changed. Be
sure to include the importance of <i>supercooling</i>.
<li>Describe the <i>mysteries</i> of the Universe 
<i>Inflation</i> solves and explain how <i>Inflation</i> solves them.
<p>
<li>How old is the Universe? How do we arrive at this age estimate? 
How old are the oldest
stars in the Milky Way galaxy? 
Is there a problem with this age for the oldest stars?
<li>Sketch the scale factor, R(t), for a universe with a constant expansion 
rate. Sketch R(t) for a closed universe, an open universe, and a flat universe.
Explain why the age estimated for the universe under the assumption that the 
expansion rate is unchanging is an overestimate for the age of the universe
if the actual expansion rate for the universe is getting smaller (that is, for
a "slowing" universe).
<li>What is the correct order for the radiation era, the matter era, and the
dark energy era? When and why did the transitions from era to era occur?
(What is meant by radiation era, matter era, and dark energy era?)
<li>Describe how the Universe evolved starting from the Planck Era (what is
meant by the Planck Era) to the GUTs to the Quark Era to Nuclear
(Nucleosynthesis) Era and to the formation of the CMBR. 
<li> Big Bang Nucleosynthesis. When were the chemical elements
present in the Universe formed? Why were they not formed earlier (what is
the deuterium bottleneck?)
What chemical elements were produced in the Big Bang? 
Why weren't elements like carbon, nitrogen, and oxygen produced in the
Big Bang? What is the significance of the
detection of deuterium? 
<li>What is meant by symmetry breaking? What were the various 
symmetry breakings which occurred in the evolution of the Universe? 
<li>What are quarks, gluons, leptons, and neutrinos? What are the
<i>fundamental</i> particles? Whyd did the quark era end? 
What are the baryons? When did baryons 
come into existence? What is baryogenesis?
When did pair production of baryons end? Why did pair production of 
baryons end?
<li>What is Recombination? When did it occur? What are the consequences of 
recombination? What does it have to
do with the CMBR?
<ul>
<li>Describe the connection between observations of the temperature fluctuations
in the CMBR and the observed structures in the Universe, and then describe how 
these observations lead to constraints on dark matter.
<li>What is meant by pair production? What is meant by 
annihilation? Physicaly, what is the meaning of
E = mc<sup>2</sup>? How do these notions lead to conundrum of the 
the Matter/Anti-Matter
Asymmetry? 
<li>What are <i>virtual pairs</i>?
What is the Heisenberg Uncertainty Principle? How does the notion 
of the Heisenberg 
Uncertainty Principle lead to virtual pairs. 
<li>Cosmological Constant. How do virtual pairs lead to 
a possible explantion for the Cosmological Constant? How does a matter 
particle differ from its anti-matter twin? We say that the Cosmological 
Constant corresponds to negative pressure. Explain this comment.
What is the cosmological constant problem?
</ul></ul>
<p><hr><p>
The Ulimate Fate for the Universe: Methods Used to Determine the Fate
<p>
<ul>
<li>What observations are made to determine the expansion rate of the Universe?
Based on observations, roughly how old is the Universe? Explain how this
estimate depends on the particular model for the Universe (we assume to 
be correct). (Show how scale factor R(t)
plots demonstrate these effects.)
<li>Examination of the behavior of the Hubble Law at large z. How is the 
<i>Hubble Law</i> at large z determined? Which standard candle is used in 
this exercise? What is the fate of the Universe implied by these results?
Sketch the Hubble relation and its behavior for large redshift z. How did
we infer that dark energy dominates the evolution of the Universe at the 
present time based on these observations? 
<li>Comparison of the models of the Universe to the CMBR. How did WMAP use
the small fluctuations in the CMBR to determine the dark matter content of
the Universe? What is the dopole anisotropy? (by the way, what WMAP stand
for?) What does the CMBR say about the
efficacy of inflation as a model for the early expansion of the Universe?
Describe the basic results of the analysis of the CMBR data obtained by WMAP.
</ul>
<li>What is current best model for the Universe? What is the Universe composed
of for the best model? Cite the evidence that leads to our current best model
for the Universe? 
</ul>
<p>
<p><hr><p>
<p><hr><p>