The Big Bang Theory: Did Stephen Hawking Ever Guest Star On The Show?

Many celebrities and thought leaders made notable cameos during the run of "The Big Bang Theory." With this in mind, those new to the series might be wondering if legendary scientist Stephen Hawking ever appeared on the show. As it turns out, Stephen Hawking absolutely did guest star on "The Big Bang Theory" — and he actually appeared on the show seven times between in-person performances and voice-overs.

Before the legendary scientist and professor passed away in 2018 at the age of 76, Hawking made a handful of appearances on the popular CBS sitcom, starting with Season 5's "The Hawking Excitation." When Sheldon Cooper (Jim Parsons) learns that his friend and CalTech colleague, Howard Wolowitz (Simon Helberg), might get a chance to meet Hawking, he wants to join. Subsequently, Howard gets Sheldon to perform a bunch of tasks like polishing Howard's beloved belt buckles. When Sheldon finally gets to meet Hawking, he passes out when the professor points out an inaccuracy in Sheldon's work.

The following season, Hawking appeared in voiceover when it's revealed that he and Sheldon regularly play Words with Friends. The professor reappears in person in Season 7's "The Relationship Diremption" when Sheldon drunk-dials Hawking after a breakup, and then again in Season 8's "The Troll Manifestation," when it turns out Hawking is anonymously trolling Leonard Hofstadter (Johnny Galecki) and Sheldon's work. Hawking then did two "video-chat" appearances in Season 9 (for Sheldon's birthday in "The Celebration Experimentation") and Season 10 (in "The Geology Elevation" to counsel Sheldon). Finally, in the Season 11 premiere, Hawking provides one last voice-over to congratulate Sheldon on his engagement to Amy Farrah Fowler (Mayim Bialik).

After seven appearances on "The Big Bang Theory," Stephen Hawking definitely charmed the show's fans. In fact, fans chose him as their favorite guest star in a 2022 poll. Hawking ultimately scored 57% of the vote, followed by stars like James Earl Jones, Bill Nye, and the late Carrie Fisher. 

These are just a few of the major stars who stopped by "The Big Bang Theory" during its 12-season run, playing themselves in a variety of ridiculous situations. Joe Mangianello shows up in Season 12, alongside Kareem Abdul-Jabbar, William Shatner, and Wil Wheaton, all playing a game of Dungeons & Dragons together. Wheaton frequently appears on the series, positioned as a sort of nemesis for Sheldon. LeVar Burton also appears as himself in a few episodes, including ones where he joined Amy and Sheldon for their makeshift online show, "Fun with Flags." Sarah Michelle Gellar even showed up in the series finale as Raj Koothrappalli's (Kunal Nayyar) date to the Nobel Prize ceremony where Amy and Sheldon are being honored. 

Stephen Hawking was one of many famous figures to show up on "The Big Bang Theory." And following Hawking's passing in 2018, the sitcom found a way to honor his legacy — even if many fans never got to see it.

"The Big Bang Theory" actually filmed a scene in tribute to Stephen Hawking just a few months after the legendary scholar's passing in March 2018 — but it ended up as a deleted scene that was cut for time. In the Season 11 finale "The Bow Tie Asymmetry," Hawking sends Sheldon and Amy a wedding present ahead of the couple's nuptials — a pocket watch engraved with his congratulations.

In an interview with The Hollywood Reporter, after the episode aired, showrunner Steve Holland said that the scene was simply an effort to honor Hawking's legacy despite the fact that they couldn't include it. "When we heard of Hawking's passing, we wanted to do something to honor him, but we had already shot the next three episodes," Holland said. "It's hard for us to be super timely because we shoot ahead of our airdates so this seemed like a really nice opportunity." Obviously, the clip went live online pretty much immediately.

At the end of the clip, some on-screen text honors Hawking once more. "To one of the greatest minds in the universe and dear member of our family," it reads. "We will miss you deeply. With love, from everyone in The Big Bang Theory family."

"The Big Bang Theory" is available to stream on Max — including all of Hawking's guest appearances.