Physics 3220 Course Syllabus

Spring 2005

Essential Information

Introduction

Physics 3220, Quantum Mechanics I, is a Junior level course in quantum physics. We will cover the basic postulates of quantum theory, the one-particle Schroedinger equation in one, two, and three dimensions, orbital angular momentum, and spin. We will use both the wave mechanics description invented by Schroedinger and the more general operator approach discovered by Heisenberg. (The second semester of this sequence covers approximation methods, scattering, and many-particle systems.) The course is taught with three lectures per week. There are weekly problem sets and office hours. We will have an in-class midterm and a final exam.

Students in Physics 3220 should already have taken General Physics 1, 2, and 3, or similar courses at the Freshmen/Sophomore level, and a course in linear algebra and differential equations such as APPM 2360. We will assume that you have already had an introduction to wave mechanics at the level of General Physics 3. A Junior level course in mechanics (PHYS 3210) would be helpful but is not essential.

Scope

Quantum mechanics was originally developed to describe the behavior of electrons in atoms. The electronic physics of atoms, molecules, and solids is still today the largest area of application, but as far as we know quantum mechanics applies to everything. Quantum mechanics is more analogous to Newton's laws than to a specific theory such as Maxwell's in that it is a general framework rather than a description of a particular physical system. It can be thought of as the generalization of Newton's laws that must be used whenever the wave-like properties of matter are important. There are plenty of things that are not understood in physics, but as far as we know no system behaves in a way that is outside the scope of quantum mechanics. Even the most highly speculative theories of physics at ultra high energies (such as string theory) are forms quantum mechanics.

Quantum mechanics is one of the most practical areas of physics. Until the advent of computers it was hard to apply quantum mechanics to most realistic systems, but today it is commonplace to calculate quantum properties of atoms, molecules, and solids. Chemist use quantum mechanics on a daily basis to predict properties of molecules, including bond energies, vibrational modes, charge distributions, and excited state properties. The interaction of light with matter plays a role in many areas where quantum physics is essential. Examples in biology include photosynthesis and vision, in astronomy the properties of stars are understood through spectroscopy, and engineers working with lasers, photodetectors, and semiconductor devices used quantum mechanics regularly.

In academic labs, many aspects of quantum physics are under active development. Current topics include Bose-Einstein condensation of atomic vapors, superconductivity, quantum cryptography, the quantum Hall effect, quantum computing, quantum magnetism, and macroscopic quantum coherence. Increasing emphasis on nanotechnology research has brought many applied scientists into the quantum domain.

Since the very first papers of Schroedinger, quantum mechanics has raised difficult interpretational and philosophical problems. Although some progress has been made, there are still issues that are far from settled, especially those related to the interface between the quantum description and classical reality.

Grading

Your course grade is determined by a combination of your performance on exams and problem sets. Notice that 60% of the grade is from the problem sets and only 20% from the final. This is to encourage steady participation.

Exams

Exams are scheduled as above. The midterm is in-class and will be worth 400 points. The final will also be worth 400 points. The final exam time is scheduled by the registrar and cannot be changed. Solutions to the exams will be posted on the web site.

Texts

The text we will use is "Quantum Mechanics," by Alastair Rae. Always read sections of the text before we cover them in class. If you do, you’ll get much more out of the lectures. We will cover almost all of Chapters 1-6. If you want a reference book on quantum mechanics written at a slightly higher level than Rae, I recommend "Principles of Quantum Mechanics" by R. Shankar. For the philosophical issues raised by quantum mechanics I'd suggest Rae's popular book "Quantum Physics, Illusion or Reality?" I will draw a little of the lecture material from both Shankar and Rae's popular book, but I will not assume you own either of these. The contents of this course are fairly standard and there are many other texts that cover the material, including Gaziorowicz, Messiah, Griffiths, Cohen-Tannoudji , Liboff, and Schiff. You might find it useful to have one of these (or Shankar) for another point of view. If you need help with linear algebra or differential equations I suggest "Mathematical Methods in the Physical Sciences," by Mary Boas.

Homework

There will be 12 weekly problem sets, worth 100 points each. This is the most important part of the course. Most students benefit from working problems in a group and you are encouraged to do this. However, it is very important to solve and understand every problem yourself. Use help from others only when you get stuck. Limit yourself to verbal help; do not take any written information from others and do not make written notes when you talk to others. This will ensure that you think things through independently after you get help. If you are doing well on homework and poorly on exams, you are probably getting too much help.

No late homeworks will be accepted. If something happens that makes it impossible for you to complete a homework, we will excuse you from that assignment. Be sure that you go back and work the problems as soon as you can.

Graduate Students Bryan Killett and Jason Gray will be grading your homeworks on alternate weeks, based on solutions and grading guides that I provide. Solutions to the homeworks will be posted on the web site.

Web Site

The web site for Physics 3220 is here. It provides information on all course activities. You must check the web site regularly.

Office Hours

The schedule of office hours will be announced later. In general, Professor Price's office hours are for physics questions, and the graduate student office hours are for questions about homework grading.

How to succeed in this course

1. Read the text section before lecture. If you read it first, it’ll sink in faster during lecture.
2. Take notes on your reading and write down questions you have so you can ask them in class.
3. Come to class and stay involved. Come to office hours with questions.
4. Start the homework early. Give yourself the time to work and understand. No one is smart enough to do the homework in the last hour before class, and no one is smart enough to learn the material without working problems.
5. Work together. You need to do your own thinking, but talking to others is a great way to get unstuck.
6. Don't skip anything. Every stone in the wall rests on another, and the whole thing won't stay up if there are any missing.
7. Don’t get behind. It’s very hard to catch up.

Disabilities

If you qualify for accommodations because of a disability, please submit a letter to the instructor from Disability Services in a timely manner so that your needs may be addressed.  Disability Services determines accommodations based on documented disabilities.  Contact: 303-492-8671, Willard 322, or click here.

Religious Observances

Campus policy regarding religious observances requires that faculty make every effort to reasonably and fairly deal with all students who, because of religious obligations, have conflicts with scheduled exams, assignments or required attendance.  In this class, please send an e-mail to the instructor in the first week of classes if you anticipate a conflict. See campus policy here.

Classroom Behavior

Students and faculty each have responsibility for maintaining an appropriate learning environment. Students who fail to adhere to behavioral standards may be subject to discipline. Faculty have the professional responsibility to treat students with understanding, dignity and respect, to guide classroom discussion and to set reasonable limits on the manner in which students express opinions. See policies here and here.

Honor Code

All students of the University of Colorado at Boulder are responsible for knowing and adhering to the academic integrity policy of this institution. Violations of this policy may include: cheating, plagiarism, aid of academic dishonesty, fabrication, lying, bribery, and threatening behavior.  All incidents of academic misconduct shall be reported to the Honor Code Council (send e-mail; 303-725-2273). Students who are found to be in violation of the academic integrity policy will be subject to both academic sanctions from the faculty member and non-academic sanctions (including but not limited to university probation, suspension, or expulsion). Additional information onthe Honor Code can be found here and here.