The Big Bang Theory Wiki

Bertram "Bert" Kibbler, Ph.D. is a professor of geology at Caltech and a 2016 MacArthur Fellow.

Bert first appeared in "The Contractual Obligation Implementation" as a socially awkward character that Raj met just prior to a library date with Lucy. He asked to join their date, but Raj sent him away. While leaving he gives Lucy a fair warning about Raj. This character is unnamed in the plot, but the closing credits gave the name "Bert".

Bert also appears when he meets Amy while she was working in her own lab at Caltech, in "The Occupation Recalibration". Bert keeps bringing Amy interesting and beautiful rocks every day. It takes Howard and Raj to make Amy aware that he likes her. Bert then asks her to a rock show which she declines because she has a boyfriend. When Bert starts talking about how no one wants to do anything with him, Amy, in a fit of sympathy agrees to go. Unfortunately, Bert is taking it as a date. Rajesh Koothrappali and Howard offer to talk to him to let him down easy and they end up going with him to the rock show, nowhere near as enthusiastic as Bert as they're with him in the car.

In "The Dependence Transcendence", Bert hosts a Caltech party that only Amy and Penny attend. He feels that Amy is the coolest girl at work and that Sheldon is cool only because he is dating Amy. As the girls are leaving Penny tells a geology joke, and he says they have to leave because he is in love with both of them.

He reappeared in "The Fetal Kick Catalyst" as a guest at Shamy's brunch in their apartment. He mentions that a girl he was living with once moved out and took all his best rocks.

He reappeared in "The Geology Elevation" after winning a $500,000 MacArthur Fellowship grant from Caltech which makes Sheldon jealous. He admits that he has a thing for Amy, but once he won his grant he thinks that he could do better. He also thinks about nominating Howard for another one which, irritates Sheldon even more.

Bert reappeared in the episode "The Allowance Evaporation" where he is with Shamy on their date night due to his own date bailing on him. He also casually reveals his knowledge of Amy and Sheldon having coitus annually, much to her chagrin.

He reappeared in "The Separation Agitation", and it was revealed that he has a recent girlfriend named Rebecca, whom he met after winning the MacArthur Fellowship (and accompanying $500,000 prize). However, it appeared that Rebecca was dating Bert only for his grant money. After breaking up with her, Bert instantly regretted it and bought expensive stuff to successfully win her back.

In "The Geology Methodology", Bert asks Sheldon to collaborate with him on a Dark matter project involving neutrino signatures, an idea which Sheldon likes, but is embarrassed to tell others that he is working with a geologist. When Bert learns this he stops working with Sheldon and replaces him with Leonard.

He appeared in "The Solo Oscillation" where he replaced Howard in Howard and Raj's band "Footprints on the Moon" and Howard eventually rejoined.

In "The Bow Tie Asymmetry", Bert went to the Shamy wedding. Howard thought he cleaned up nice and Bert compared himself to a geode, which has to be broken open to see the beauty.

He reappeared again in "The Wedding Gift Wormhole", when Amy and Sheldon were on a scavenger hunt and needed some help figuring out what the wedding gift was; it turned out to be a quartz chakra wand.

In "The Meteorite Manifestation", Bert wants Raj's help cutting open a meteorite with a band saw. Leonard wants to do it with his laser, but Bert declines. Leonard gets angry that he is left out. He steals the meteorite, cuts it open and then gets infected with an virus that turns him in to a flesh eating zombie. He wakes up, starts to glow and then attacks Penny and wakes up again. Finally he apologizes to Bert and Raj.

In "The Inspiration Deprivation", Howard bought a scooter like he used to own, with he and Raj planning to relive their good old days. Bernadette was angry and didn't want him to get hurt. He therefore sold it to Bert who immediately had an accident. At the emergency room, he met a nurse that gave him her number.

In the series finale, Bert looked after Cinnamon for Raj. He intended to use Cinnamon to help get girls and said he would let Raj know if she were to die in his care post joking where he can find a dog that looks JUST like her.

The Occupation Recalibration 8

Bert and Amy.


  • Bert is known for being a "gentle giant", likely reference to his kind nature during the show.
  • He often made jokes concerning rocks and stones due to his specialty in Geology.
  • Like David Gibbs and Zack Johnson, Bert was taller than Sheldon.
  • Bert seemed to have an interest in Dungeons & Dragons as he owns items relating to the game in The Dependence Transcendence.
  • In the episode The Geology Methodology, a certificate on Bert's office wall indicated that he attended the University of Arizona.



The Big Bang Theory Episodes
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Tot
Season 1 0
Season 2 0
Season 3 0
Season 4 0
Season 5 0
Season 6 1
Season 7 1
Season 8 0
Season 9 0
Season 10 M 5
Season 11 3
Season 12 M 5


Young Sheldon Episodes
 1   2   3   4   5   6   7   8   9  10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Tot
Season 1 0
Season 2 0
Season 3 0
Season 4 0
Season 5 0
Season 6 0
Season 7 0
Appeared M = Mentioned Did not appear Not aired/Not available
V = Voiced C = Cameo F = Flashback I = Indirectly mentioned P = Pictured