Physics 161, Astrophysics and Cosmology Fall 2011

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1 Physics 161 page 1/5 Physics 161, Astrophysics and Cosmology Fall Course Description - Instructor: Dr. Derrick Kiley Office: AOB 177; Office Phone Address: dkiley@ucmerced.edu. Course Webpage: 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,. 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. 1

2 Physics 161 page 2/5 - Tentative Syllabus - All Dates Approximate! Topic Date Sections in Text Quarks and Leptons and Their Interactions Monday August Quarks and Leptons and Their Interactions Wednesday August Labor Day - NO SCHOOL! Monday September 5 Relativistic Transformations Wednesday September and the Equivalence Principle Relativistic Transformations Monday September and the Equivalence Principle Conservation Rules, Symmetries, Wednesday September Conservation Rules, Symmetries, Monday September Conservation Rules, Symmetries, Wednesday September Extensions of the Standard Model Monday September Extensions of the Standard Model Wednesday September The Expanding Universe Monday October The Expanding Universe Wednesday October The Expanding Universe Monday October The Expanding Universe Wednesday October Nucleosynthesis and Baryogenisis Monday October Nucleosynthesis and Baryogenisis Wednesday October Dark Matter and Dark Energy Components Monday October Dark Matter and Dark Energy Components Wednesday October Dark Matter and Dark Energy Components Monday October Development of Structure in the Early Universe Wednesday November Development of Structure in the Early Universe Monday November Development of Structure in the Early Universe Wednesday November Cosmic Particles Monday November Cosmic Particles Wednesday November Cosmic Particles Monday November Cosmic Particles Wednesday November Cosmic Particles Monday November Particle Physics in Stars and Galaxies Wednesday November Particle Physics in Stars and Galaxies Monday December Particle Physics in Stars and Galaxies Wednesday December

3 Physics 161 page 3/5 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. 3

4 Physics 161 page 4/5 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 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. 4

5 Physics 161 page 5/5 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. 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. 5