Download Physics 161, Astrophysics and Cosmology Fall 2011

Physics 161 page 1/5
Physics 161, Astrophysics and Cosmology
Fall 2011
- Course Description Instructor: Dr. Derrick Kiley
Office: AOB 177; Office Phone 209 228-3077
E-mail Address: [email protected].
Course Webpage: http://faculty.ucmerced.edu/dkiley/physics161fall2011.html.
Class meets: 10:30 - 11:45, Mondays and Wednesdays in CB 267.
Discussion Sessions (optional): Fridays 10:30 - 11:30 in CB 264.
Office hours: Mondays, and Wednesdays 9:20 - 10:20 in AOB 177.
Textbook:
Required: Particle Astrophysics, Second Edition (Oxford Master Series in Physics) by
Donald Perkins.
Recommended: Astrophysics in a Nutshell, (In a Nutshell (Princeton)) by Dan Maoz.
Additional materials will be provided by the instructor.
Topics and Outlook:
It is the goal of physics in general (and cosmology, specifically) to try to explain where
the Universe came from and how it evolves. As we will see, this will not be an easy task, in
general. The attempt to describe the Universe will lead us into new and exciting areas of
physics, including Einstein’s General Theory of Relativity, as well as the laws of quantum
mechanics. The work done in achieving the goal will be well-worth it, however. We’ll
begin our journey by making some observations about the Universe. We will find that these
observations lead to some very interesting puzzles which will require some new ideas to
address. It will, in fact, be our goal to solve these puzzles.
The basic building blocks of the Universe are particles interacting via the exchange of
bosons. We will throughly investigate the fundamental interactions of the particles, learning
how to draw Feynman diagrams depicting these interactions. We will spend a considerable
amount of time learning different aspects of particle physics (most specifically, those aspects
that are useful for astrophysics and cosmology), including their relativistic description, symmetries, and the Standard Model of Particle Physics. Once we have set the stage with the
actors, we can proceed to the play, investigating the origin and subsequent evolution of the
Universe. We will see that the Universe is expanding (and, in fact, even accelerating in
its expansion!), suggesting that it originated from a tiny region. This simple picture of a
hot Big Bang turns out to have a number of problems associated with it. In our attempt to
address these problems, we will discuss how this primordial region expanded faster than light
(inflated), stretching out tiny quantum fluctuations to grow into the initial seeds of galaxies
and clusters of galaxies. After discussing the large-scale structure of the Universe, we turn
our attention toward far smaller objects, and finish our discussions with the astrophysical
processes occurring in stars and galaxies. We will see the evidence that the vast majority
of constituents of our Universe are invisible to us, taking the form of dark energy and dark
matter. We will also discuss the lifecycle of stars, from their initial formation inside a nebula
to their death, perhaps as a black hole. If time permits, we can discuss other topics of
student interest, such as new ideas in cosmology based on extra-dimensional theories, etc.
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- Tentative Syllabus All Dates Approximate!
Topic
Date
Sections in Text
Quarks and Leptons and Their Interactions
Monday August 29
1.1 – 1.7
Quarks and Leptons and Their Interactions
Wednesday August 31
1.8 – 1.12
Labor Day - NO SCHOOL!
Monday September 5
Relativistic Transformations
Wednesday September 7
2.1 – 2.6
and the Equivalence Principle
Relativistic Transformations
Monday September 12
2.7 – 2.12
and the Equivalence Principle
Conservation Rules, Symmetries,
Wednesday September 14
3.1 – 3.7
and the Standard Model of Particle Physics
Conservation Rules, Symmetries,
Monday September 19
3.8 – 3.10
and the Standard Model of Particle Physics
Conservation Rules, Symmetries,
Wednesday September 21
3.11 – 3.17
and the Standard Model of Particle Physics
Extensions of the Standard Model
Monday September 26
4.1 – 4.3
Extensions of the Standard Model
Wednesday September 28
4.4 – 4.6
The Expanding Universe
Monday October 3
5.1 – 5.3
The Expanding Universe
Wednesday October 5
5.4 – 5.7
The Expanding Universe
Monday October 10
5.8 – 5.11
The Expanding Universe
Wednesday October 12
5.12 – 5.14
Nucleosynthesis and Baryogenisis
Monday October 17
6.1 – 6.3
Nucleosynthesis and Baryogenisis
Wednesday October 19
6.4 – 6.6
Dark Matter and Dark Energy Components
Monday October 24
7.1 – 7.6
Dark Matter and Dark Energy Components
Wednesday October 26
7.7 – 7.13
Dark Matter and Dark Energy Components
Monday October 31
7.14 – 7.17
Development of Structure in the Early Universe Wednesday November 2
8.1 – 8.5
Development of Structure in the Early Universe
Monday November 7
8.6 – 8.12
Development of Structure in the Early Universe Wednesday November 10
8.13 – 8.17
Cosmic Particles
Monday November 14
9.1 – 9.5
Cosmic Particles
Wednesday November 16
9.6 – 9.11
Cosmic Particles
Monday November 21
9.12 – 9.14
Cosmic Particles
Wednesday November 23
9.15 – 9.18
Cosmic Particles
Monday November 28
9.19 – 9.22
Particle Physics in Stars and Galaxies
Wednesday November 30
10.1 – 10.5
Particle Physics in Stars and Galaxies
Monday December 5
10.6 – 10.10
Particle Physics in Stars and Galaxies
Wednesday December 7
10.11 – 10.13
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Grading:
The grading will be based on 12 homework sets (70% total), and the final
project/presentation (30%).
Homework
There will be 12 homework assignments, due by the end of class the following
Wednesdays, giving you one week to finish them. We will do our best to give plenty of
partial credit, so always attempt the problems, even if you don’t finish them. Because the
homework solutions will be posted immediately, no late homework will be accepted ! While
you are of course permitted (and even encouraged ) to work together, it is your responsibility
to complete, understand, and hand in your own assignment.
Final Project/Presentation: Thursday, December 15: 6:30 – 9:30. The final
will be based on a 5 - 10 page paper, as well as a ten-minute presentation (with an additional
five minutes for questions) on a topic chosen by the student and cleared by the instructor.
The topic can be anything having to do with astrophysics or cosmology, either material that
we did not have time to cover, or aspects of topics that we did cover described in greater
detail. Possible topics include (but are certainly not limited to) black holes, pulsars, stellar
lifetimes, neutrino oscillations, modified Newtonian gravity, modified gravitational theories,
extra dimensional theories, etc.
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Learning Objectives for Physics 161
Upon completion of Physics 161, you should understand :
• the difference between fermions and bosons, and that interactions between particles
arises from the exchange of a boson.
• the basic aspects of Einstein’s Special and General Theory of Relativity, including the
spacetime metric.
• the vital role that symmetries and conservation laws play in physics, in general.
• the basic constituents of the Standard Model of Particle Physics, as well as various
extensions to the model.
• that the Universe is expanding, and the FRW metric that describes that expansion.
• that the Cosmic Microwave Background radiation provides an “afterglow” of the Big
Bang, and the temperature inhomogeneities provided initial density perturbations
which led to structure formation in the Universe.
• the evidence for both dark matter and dark energy.
• the different problems associated with a hot Big Bang model, such as the horizon and
flatness problems.
• that the structure in the Universe arose from quantum fluctuations produced during
inflation.
• that neutrinos can change flavor.
• the basic astrophysical processes occurring in stars, such as electron degeneracy pressure, as well as processes involving black holes.
Learning Outcomes for Physics 161
Upon completion of Physics 161, you should be able to:
• draw various Feynman diagrams representing the interaction of particles.
• make a variety of relativistic calculations using four-vectors and basic tensors.
• demonstrate a basic understanding of Gauge transformations.
• calculate various parameters of the Universe, such as its age and size.
• calculate the basic dynamics of the evolution of the Universe based on the Friedmann
equations.
• show that Newtonian gravity cannot explain galactic rotation curves.
• show that the theoretical value for dark energy differs from the observational value by
a factor of ∼ 10120 .
• show how inflationary cosmology solves the various problems associated with the hot
Big Bang model.
• calculate various inflationary parameters, such as the power spectrum.
• calculate various astrophysical aspects of black holes.
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Academic integrity
Academic integrity is the foundation of an academic community and without it none
of the educational or research goals of the university can be achieved. All members of the
university community are responsible for its academic integrity. Existing policies forbid
cheating on examinations, plagiarism and other forms of academic dishonesty. The current
policies for UC Merced are described in the UC Merced Interim Academic Honesty Policy
and Adjudication Procedures available from Students First Center, Student Life, Residence
Life and College One. Information is available through the Student Judicial Affairs link on
the Student Life web page. http://studentlife.ucmerced.edu/.
Examples of academic dishonesty include:
• Receiving or providing unauthorized assistance on examinations.
• Using unauthorized materials during an examination.
• Plagiarism - using materials from sources without citations.
• Altering an exam and submitting it for re-grading.
• Fabricating data or references.
• Using false excuses to obtain extensions of time or to skip coursework.
The ultimate success of a code of academic conduct depends largely on the degree to which
the students fulfill their responsibilities towards academic integrity. These responsibilities
include:
• Be honest at all times.
• Act fairly toward others. For example, do not disrupt or seek an unfair advantage over
others by cheating, or by talking or allowing eyes to wander during exams.
• Take group as well as individual responsibility for honorable behavior. Collectively, as
well as individually, make every effort to prevent and avoid academic misconduct, and
report acts of misconduct which you witness.
• Do not submit the same work in more than one class. Unless otherwise specified by the
instructor, all work submitted to fulfill course requirements must be work done by the
student specifically for that course. This means that work submitted for one course
cannot be used to satisfy requirements of another course unless the student obtains
permission from the instructor.
• Unless permitted by the instructor, do not work with others on graded coursework,
including in class and take-home tests, papers, or homework assignments. When an
instructor specifically informs students that they may collaborate on work required
for a course, the extent of the collaboration must not exceed the limits set by the
instructor.
• Know what plagiarism is and take steps to avoid it. When using the words or ideas of
another, even if paraphrased in your own words, you must cite your source. Students
who are confused about whether a particular act constitutes plagiarism should consult
the instructor who gave the assignment.
• Know the rules – ignorance is no defense. Those who violate campus rules regarding
academic misconduct are subject to disciplinary sanctions, including suspension and
dismissal.
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