In the 21st century, now that I'm retired from research and teaching, I'm trying to write for a more general audience in the two major areas of my interest - science and history. (Although I do read and enjoy some fiction, I mostly read non-fiction in science and in history, and that's what I write.) I have another popular-science book coming out soon (Rising Force: The Magic of Magnetic Levitation, Harvard, 2011), but my last two books have been in history.

My interest in history has been mostly in American history, and it has been influenced by another personal interest - genealogy and family history. I seem to be most interested in history when I have a personal connection to the protagonists. My wife Sherry Penney and I wrote a scholarly biography of my ancestor Martha Wright, who was active in the early women's rights and abolition movements: A Very Dangerous Woman: Martha Wright and Women's Rights, UMass Press, 2004.

My latest book in history is in the true-crime genre: Arsenic and Clam Chowder: Murder in Gilded Age New York, SUNY Press, 2010. Over 30 years ago, I was studying Livingston genealogy and ran across a black-sheep cousin who in 1896 was tried for murdering her mother. She was an unwed mother of four, the last born in prison as she awaited trial. I thought her story would make a great book, and now that I'm retired from physics, I finally had the time to research and write it.