An Introduction to Mechanics (SIE) About the Author Robert J. Kolenkow is professionally a physicist and an author of several books. In addition to his book An Introduction to Mechanics (SIE), he has also co-authored another book titled Physical Geography Today: A Portrait of a Planet. He is known for his simple writing style and in-depth knowledge of technical subjects. In the past, he has been a professor of Physics, and graduated from MIT university in 1955. Daniel Kleppner also is a professional physicist and a specialist of atomic physics. He received the Davisson Germer Prize in surface and atomic physics in 1986, and the National Medal of Science in 2006.