Physicist Stephen Hawking Dead at 76: The Big Bang Theory Cast Pays Tribute

Stephen Hawking, the world-renowned physicist who authored A Brief History of Time, died on Wednesday morning after a decades-long battle with ALS. He was 76.

Hawking’s children, Lucy, Robert and Tim, announced their father’s passing in the following statement:

Hawking was first diagnosed with ALS in 1963, at the age of 21. He was only expected to live for another couple of years, but was ultimately discovered to have a rare form of the disease that progressed at a much slower rate. He was able to walk on his own for much of the 1960s with the help of crutches, but eventually required a mobilized wheelchair. When he lost the use of his voice, he began using a unique method of synthesized computer vocalizations that allowed him to remain vocal for the rest of his life.

A Brief History of Time was released in 1988, and went on to sell 10 million copies, making Hawking a public figure. His life was depicted in the 2014 biopic The Theory of Everything; Eddie Redmayne went on to win the Academy Award for Best Actor in a Leading Role. Redmayne released the following statement to our sister site Deadline:

Hawking guest-starred as himself on numerous TV shows, including Star Trek: The Next Generation and The Simpsons:

He later recurred on The Big Bang Theory, first appearing in the Season 5 episode “The Hawking Excitation.” Watch his first scene opposite Jim Parsons below:

Hawking would return to Big Bang for six more episodes, including the most recent season premiere last September. Cast members — as well as co-creator Bill Prady — shared the following tributes on social media:

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