Department of Physics,
Physics 622----Quantum Physics I----Fall 2008
Instructor: Prof. Thomas Cohen (I prefer to be
addressed as Tom)
Office: 2104 (
Phone: 5-6117 (Office); 301-654-7702 (Home---call before 10:00 p.m.)
Office hours are immediately following class. I am also generally available in my office and happy to see students; just drop by--or, better yet, give me a call and then drop by.
In my opinion quantum mechanics is one of the most intellectually beautiful subjects in all of physics. It is a very rich subject in terms of both the phenomena it describes and in its formal structure. This course will focus on the formal structure of the theory. Applications of quantum mechanics will largely be the domain of Physics 623.
The general approach will be Dirac’s abstract vector space approach. There will be three main parts to the course: i) the logical and mathematical structure of the theory, ii) Quantum dynamics, and iii) Symmetries including anglular momentum.
The course assumes that you have had a strong undergraduate background in quantum mechanics. Ideally you are comfortable with the ideas underlying Dirac’s approach (bra and ket vectors and the like). If this is not the case you may consider reviewing Liboff’s Introductory Quantum Mechanics (ISBN 0-8953-8714-5), an undergraduate level book on quantum mechanics which covers this rather well.
The main text for the course is Sakurai's Modern Quantum Mechanics (ISBN 0-201-53929-2). The book is at a fairly high level and its problems are non-trivial. The course will cover topics in the first four chapters in Sakurai and will generally cover things following the order of the book. In my view the principal virtue of this book is its high intellectual level, the depth in which it treats things and some of its challenging problems. However, it does have some important drawbacks. One of these is its emphasis on depth over breadth---many interesting topics in quantum mechanics are not addressed. Another is that in places it is not written very clearly. As a way to deal with these deficiencies, I have listed Baym’s Lectures on Quantum Mechanics (0-805-30667-6) as a recommended text. It is very clearly written and deals with a broad spectrum of problems. If you choose to purchase Baym you will likely find a very useful source for alternative explanations for things which seem obscure in Sakurai.
Problem sets will be assigned regularly. Problem sets may require the use of numerical analysis that can be done in Mathematica or some other computer program. I strongly encourage students to consult each other on problem sets. Ideally you should attempt all of the problems by yourselves and if you get stuck you should then consult your peers. Homework will count approximately 20% of the final grade.
Not all problems will be graded---a representative sample will be. A set of solutions to the homework problems prepared by the TA will be posted on the course web cite for additional feedback. These solution sets may in part consistent of corrects solutions submitted by students in the course.
There will be a midterm exam and a final exam in this course. The exams will count for approximately 80% of the total course grade.
The exams are currently
planned as take-home. Take-home exams have two virtues: they reduce the time
pressure on students and allow them to perform at their best and they allow for
questions that are less trivial than can be done during a class period. They do
have a potential drawback, however. They are impossible to police efficiently
against cheating. Thus, we must rely on your integrity. I will ask you to
pledge to do the exams alone and to stick to this pledge. I should note that
the whole enterprise of science depends on the integrity of the researchers---
when I read a scientific paper I must assume that the researchers didn't cook
the books or I won't get anywhere.
Tentative Course Outline
---The formal structure of quantum mechanics
---Time evolution and quantum dynamics
---Symmetries and conservation laws