Physics 10: Gravity and Relativity (Fall 2009)

I am very excited to be teaching a Physics 10 on the topic of Gravity and Relativity in Fall 2009! If you've ever wondered, for example, why clocks run slower near a black hole, this course is for you. Einstein's theory of general relativity---which is a theory of gravity consistent with the mind-blowing properties of space and time inroduced by special relativity---is one of the most important ideas in 20th-century physics, but because of its mathematical complexity is usually reserved for graduate students. In this course, by thinking hard about the concepts and restricting ourselves to mathematically (but not conceptually) simple situations, you will come to understand the ideas without a lot of math. Even more so, you will be expected to really think hard about the concepts rather than memorize results. It will be an intellectual adventure!

Lectures: TR 10:30-11:50am in 55 Roessler

Instructor: Prof. David Wittman, 754-5354, dmwittman@ucdavis.edu. Feel free to contact me if you'd like more information.

Office Hours: TBD, Physics 529

Textbook: Gravity from the Ground Up: An Introductory Guide to Gravity and General Relativity, by Bernard Shutz (ISBN-10: 0521455065; ISBN-13: 978-0521455060). This book makes difficult concepts accessible, but does not dumb them down. There will be sections where practically every page has a new and mind-blowing concept, and you must really think as you go. Like this course, the book is for those who really want to put in the work required to understand difficult concepts.

Prerequisites: None. High school physics will help somewhat, but it is by no means essential. You should also be comfortable with basic algebra.

More specifics on topics covered: We will build our understanding in much (but not exactly) the same order that pioneering scientists such as Galileo, Newton, and Einstein built theirs. We will start with Galileo's notion of relativity (yes, he had one three centuries before Einstein). Then we follow in Newton's footsteps as we come to understand how the same force that makes an apple fall also makes the Moon go around the Earth. Related to Newton's conception of gravity is the equivalence principle. We will develop this principle a bit more than Newton did, and show that simply following this principle would lead us to predict most of the amazing effects (such as clocks running slower near black holes) that are associated with general relativity.

Next, we jump two centuries forward as we learn about special relativity. SR contains some counterintuitive notions about space and time, but they are straightforward consequences of the fact that the speed of light is constant and the same for all observers, and SR's predictions have been experimentally verified in exhaustive detail. The counterintuitive effects are really noticable only for objects traveling near the speed of light (which is why we have no intuition about them) but conceptually they are very important so we will work very hard to understand them thoroughly.

Finally we come to the crowning achievement: understanding how gravity fits in with the ideas of special relativity. Newton's gravity simply doesn't fit, so we must develop a new theory of gravity that is consistent with SR. That theory is called general relativity, and by the end of the course and after a lot of hard work, you will really understand it!