Sad news: Stephen Hawking, quite possibly the greatest scientist of our time and the smartest person on Earth has passed away at age 76. He’s been a public figure and popularizer of science for decades, but there’s still a lot about him that most people didn’t know.

Field of Study

Hawking was a “scientist” to many, but what were his specific disciplines? He was a cosmologist, a theoretical physicist, a professor of mathematics at the University of Cambridge for 30 years, and a master at quantum theory, thermodynamics, and information theory, among others. His stature is likely due to the fact that he combined so many different fields to unlock truths about the universe.

The Big Bang and the Black Hole

Some of Hawking’s most famous and early work concerned the application of the theory of general relativity on black holes. What does that mean? It means he put out a paper that convincingly laid out an argument that the universe started like the collapse of a black hole, but backward, a.k.a. “the Big Bang.”
Also, Hawking developed a lot of what we now know about black holes, such as how they can only get bigger, not smaller.

Hefty and Dry Wit

Hawking was brilliant, of course, but he also had a hefty and dry wit. He appeared as himself on The Big Bang Theory, The Simpsons, and Futurama several times. Also, the title of his book, A Brief History of Time—a book that literally attempts to describe the science behind existence—is a very subtle but very good joke.

A Brief History of Time

Another fact about A Brief History of Time: Its time on the bestseller lists was hardly brief. It didn’t leave the U.K.’s Sunday Times bestseller list for five years. All told, it sold more than 10 million copies, which made it the most popular popular science book of all time.

The Disease

Hawking employed the use of a wheelchair for 50 years, and since the ‘80s, a voice synthesizer. That’s because at the age of 21, he was diagnosed with amyotrophic lateral sclerosis, ALS, or Lou Gehrig’s disease. At the time, doctors told him he wouldn’t live to see his 25th birthday. He certainly beat the odds, living to the robust old age of 76. Doctors attribute his longevity to extremely good medical care—a respirator and feeding tube, as well as the unique biology of his particular case of ALS.

IQ Score?

Just how smart was Hawking, exactly? He didn’t know, and he didn’t care. Hawking never had his IQ tested. “I have no idea,” he once said. “People who boast about their IQ are losers.”

Interview

Here is one of the last interviews with Stephen Hawking, by the legendary Neil deGrasse Tyson.