In this Dec. 28, 1934 photo, Albert Einstein delivers a lecture at the meeting of the American Association for the Advancement of Science in the auditorium of the Carnegie Institue of Technology Little Theater at Pittsburgh. (AP)

In November 1915, 36-year-old Albert Einstein presented his general theory of relativity to the Prussian Academy. This wasn’t the “E=mc2” document — that equation was part of the special theory of relativity that had made Einstein famous a decade earlier.

This new theory was built on the earlier work, expanding it and revolutionizing the concept of gravity, explaining how gravity arises from the curvature of space and time and including such startling observations as how gravity bends light.

The 100th anniversary of this watershed publication is being marked by several new books on Einstein, his life and his science. “The Road to Relativity” by Hanoch Gutfreund and Jürgen Renn reproduces the 45 handwritten — and hand-corrected — pages of Einstein’s general theory, accompanied by extensive annotations on the science, its historical context and the implications for the future. The volume also includes a glossary of scientists and philosophers relevant to Einstein’s work and some entertainingly lively illustrations — such as one of Einstein pouring coffee on a moving train to demonstrate that motion is relative — by Laurent Taudin.

Relativity: The Special and the General Theory” is Princeton University’s commemorative edition of a book Einstein published two years after his general theory came out — his own version of a popular explanation for non-physicists. It begins, “In your schooldays most of you who read this book made acquaintance with the noble building of Euclid’s geometry, and you remember — perhaps with more respect than love — the magnificent structure, on the lofty staircase of which you were chased about for uncounted hours by conscientious teachers.” It gets progressively harder to understand after that, but you’ve got to give a genius credit for reaching out.

(Which gives us an opportunity to repeat a version of one of the great Einstein quotes: “When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That’s relativity.”)

(Amazon.com)

Science historian Jimena Canales takes a long look at Einstein’s 1922 debate with Henri Bergson, one of the preeminent philosophers of the era, over the nature of time. In “The Physicist and the Philosopher,” Canales recounts how Bergson challenged Einstein’s theories, arguing that time is not a fourth dimension definable by scientists but a “vital impulse,” the source of creativity. It was an incendiary topic at the time, and it shaped a split between science and humanities that persisted for decades — though Einstein was generally seen as the winner and Bergson is all but forgotten.

And Steven Gimbel presents the physicist in the context of contemporary political and social events in “Einstein: His Space and Times.” Not only brilliant but also edgy and opinionated, Einstein was a complex man: a pacifist who renounced his citizenship at age 16 to protest German militarism before World War I, a Jew who left his homeland after the rise of the Nazis, a divorced man who went on to marry his first cousin and have numerous affairs, a physicist who regretted science’s role in creating the nuclear age. He died of an aneurysm at age 76: “Moments earlier, he uttered a single sentence aloud in his native tongue.

Einstein’s dying words were heard by one person, a night nurse who spoke no German. In death as in life, Albert Einstein left us a mystery.”