Product Description

Rescued from obscurity, Feynman's Lost Lecture is a blessing for all Feynman followers. Most know Richard Feynman for the hilarious anecdotes and exploits in his best-selling books "Surely You're Joking, Mr. Feynman!" and "What Do You Care What Other People Think?" But not always obvious in those stories was his brilliance as a pure scientist--one of the century's greatest physicists. With this book and CD, we hear the voice of the great Feynman in all his ingenuity, insight, and acumen for argument. This breathtaking lecture--"The Motion of the Planets Around the Sun"--uses nothing more advanced than high-school geometry to explain why the planets orbit the sun elliptically rather than in perfect circles, and conclusively demonstrates the astonishing fact that has mystified and intrigued thinkers since Newton: Nature obeys mathematics.

David and Judith Goodstein give us a beautifully written short memoir of life with Feynman, provide meticulous commentary on the lecture itself, and relate the exciting story of their effort to chase down one of Feynman's most original and scintillating lectures. David and Judith Goodstein live in Pasadena, California.

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Product Details

• Amazon Sales Rank: #768305 in Books
• Published on: 1996-05
• Number of items: 1
• Binding: Hardcover
• 191 pages

Amazon.com
Richard Feynman, the rock star of theoretical physics, has left an image that belies his nerdy side. Not many bongo-playing surfer beatniks would have spent hours of their spare time proving Newton's law of elliptical planetary motion using only plane geometry. But Feynman's Lost Lecture: The Motion of Planets Around the Sun shows that the great man did just that. Originally delivered to an introductory physics class at Caltech in 1963, this 76-minute CD and book set contains everything the math-savvy listener needs to savor the pleasures of applied math. Caltech physicist David L. Goodstein and archivist Judith R. Goodstein found the notes and tape amid another professor's papers and set to work making sense of them; unfortunately, photographs of the blackboard drawings didn't survive. The book briefly covers their find and recovery work, then presents the proof as reconstructed--crucial reading if one is to follow the lecture. There's nothing easy about it, as Feynman acknowledges in the lecture:

I am going to give what I will call an elementary demonstration. "Elementary" means that very little is required to know ahead of time in order to understand it, except to have an infinite amount of intelligence.

He means, instead, that he is strictly using geometrical methods to reach his destination, which explains why it was so difficult to reconstruct without his diagrams. His charming Brooklyn accent and good humor show through in this lecture, even if the material is quite a bit drier than his fans might expect. Still, those interested in adding a new dimension to their understanding of this brilliant scientist--and those with a deep interest in Newtonian physics--will find The Motion of Planets Around the Sun a rare and unexpected treat. --Rob Lightner

From Publishers Weekly
Isaac Newton, in his Principia Mathematica (1687), proved Johannes Kepler's law explaining why planets travel in elliptical orbits around the Sun. In 1964, theoretical physicist Richard Feynman, the bestselling author and Nobel Prize winner, set forth his own proof of Kepler's law, using only plane geometry. Feynman's difficult proof, presented in an introductory lecture to Caltech undergraduates, never made it into the classic multivolume Feynman Lectures on Physics, published between 1963 and 1965, but California Institute of Technology archivist Judith Goodstein unearthed the transcript of Feynman's 1964 lecture, published here along with explanatory commentary and historical background, plus 25 photographs and 150 diagrams. Caltech physics professor David Goodstein, Feynman's friend and colleague until the latter's death in 1988, provides a warm reminiscence and does a good job of explaining how quantum physics and relativity supplanted Newtonian science.
Copyright 1996 Reed Business Information, Inc.

From Library Journal
Not only colleagues but friends of noted physicist Richard Feynman, David and Judith Goodstein, a professor of physics and a registrar/archivist, respectively, are well qualified to present this material. Their book consists of four chapters. The first and largest is a brief history of the establishment of the Copernican cosmology, which Feynman gave as a lecture to the freshman class at Caltech. Feynman then revisits the work of Isaac Newton and the watershed proof of the Scientific Revolution that separated the ancient world from the modern. There is also chapter a with some wonderful reminiscences of Feynman. While Feynman's presentation requires only an understanding of high school geometry, some persistence will be required to grasp what he is saying. Recommended for academic and public libraries emphasizing the history of science. (CD-ROM not seen..
-?James Olson, Northeastern Illinois Univ. Lib., Chicago
Copyright 1996 Reed Business Information, Inc.

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Customer Reviews

If you are a Feynman fan
This is a lot of fun -- if. If you are pretty good at mathematical games and have a love for all things Feynman. What makes it work is the CD with Feynman giving the lecture. He goes at the speed of light, but he is always amazing, even when you have no idea what he just said! I can't imagine what it was like for the young folks trying to make sense out of what was going on. But, I bet he inspired them for the rest of their careers. He still does that to people today. If you want a sample of the Feynman magic this is a tough place to start. But do find a way to start.

Feynman's proof of the law of ellipses
First we see that planets sweep out equal areas in equal times, following Newton's easy proof. Now to prove that planets move in ellipses. Cut the orbit into infinitesimal, equiangular pieces (as seen from the sun). Each little piece of the orbit corresponds to the velocity vector at that point. Draw a velocity diagram by moving all of these velocity vectors so that they have a common origin point. Obviously, as we move around the orbit, the velocity vector will make one revolution around the origin. In fact, it will trace out a circle, as we shall now prove. The orbit is cut into infinitesimal triangles with equal angles at the sun, so clearly these triangles are similar with a scaling factor r, i.e. an area scaling factor r^2. But time is the same as area, so time also varies as r^2. The change in velocity in one of these pieces is force*time=(1/r^2)*(r^2)=independent of r, so the dv steps in the velocity diagram are all of equal size, and because of the equiangular division they all make equal angles with each other (dv parallel to PS), so the velocity vector does indeed trace out a circle, and the equiangular division of the orbit as seen from the sun translates to an equiangular division of this circle as seen from its center. Of course, the center of the circle is not the origin of the velocity vectors; in particular, the velocity vector going through the center of the circle is the longest velocity vector, so it corresponds to the position on the orbit closest to the sun (as is obvious by the law of equal areas). If we turn the orbit diagram so that this position is straight to the right of the sun, then the longest arrow in the velocity diagram points straight up, since the velocity vector drawn in the orbit diagram will of course be parallel to the tangent to the orbit. When we have advanced a given angle beyond this starting point on the orbit (as seen from the sun), the corresponding velocity vector (i.e. the tangent to the orbit at this point) is found by advancing the same angle in the velocity diagram (as seen from the center of the circle) and connecting this boundary point with the origin of the velocity vectors, and conversely. So the velocity diagram contains complete information about the tangents of the orbit, so it contains complete information about the orbit up to scaling. So the problem becomes: for any velocity diagram, to recreate the orbit. To do this we turn the velocity diagram 90 degrees to the right. To recreate the orbit we must now find a curve that is always perpendicular to the velocity vectors. This can be done as follows. For any point p on the circumference of the velocity diagram circle, draw the line connecting it to the origin O of the velocity vectors and the line connecting it to the center C of the circle. Mark the point P where the perpendicular bisector of Op cuts Cp as a point on the orbit. Now we prove that the orbit generated in this way, as p moves around the circle, is an ellipse (we assume O to be inside the circle; if it was on the boundary the orbit would be a parabola, etc.). The perpendicular bisector cuts the triangle OPp into congruent halves (SAS), making OP=Pp, so CP+OP=CP+Pp=radius of the circle=independent of p, so P traces out an ellipse with foci C and O, and the perpendicular bisector is tangent to this ellipse (because all its other points are outside of the ellipse because they have greater sum of distances to the foci), as required. QED.

Lucid explanation of Feynman's proof of the law of ellipses
The book first walks you through the works of Copernicus, Galileo, Brahe and Kepler. Then it gives a brief account of Feynman's life and his work. Then, through numerous diagrams, the authors clearly explain Feynman's ingenious proof of the law of ellipses. Finally, the book presents Feynman's lecture "The Motion of Planets Around the Sun".

It is amazing how Feynman, starting on the lines of Newton, and then not being able to follow Newton's reasoning, devised a different but elegant proof of the law of ellipses.