It’s been established that Howard’s Masters is from MIT. But have they mentioned where Sheldon, Raj and Leonard (and Bernadette for that matter) got their doctorates?
I assume Bernadette’s PhD came from the university they all work at (do they name Cal Tech in the show? I can’t remember)
Bernadette doesn’t work at Caltech, and I assume she didn’t go there since they never interacted with her as a student. So she probably got her doctorate at UCLA.
Leonard got his PhD from Princeton. I’m not sure about the others.
We know Raj attended the University of Cambridge, but it is unknown if he got his doctorate there.
I believe that it has been mentioned that Raj studied in Cambridge (England), although that might have been his undergraduate degree. Otherwise, I do not recall it being clearly said, but by default one might assume they got their doctorates at Caltech, where they still work. This would not be unusual. Caltech likes to think its students, as well as its faculty, are the best at every level.
Howard’s MIT Master’s is a bit of an in joke, I think. Caltech definitely feels a strong rivalry with MIT, and there is a (semi-humorous) tendency to disparage MIT and regard it not quite up to Caltech’s standards. (Caltech, being a lot smaller, can plausibly claim to be more selective.) When MIT goes one way one way, Caltech tends to go the other: for instance, when MIT became a leading enter for artificial intelligence research, which spilled over into cognitive psychology, and poured a lot of money into these areas, Caltech largely ignored both AI when it seemed to be the hot new way of studying the mind, and did not have a psychology program at all, but instead built up its strength in neuroscience. Howard is being teased not just because he only has a Master’s rather than a doctorate (and in Engineering rather than a real science), but also because that Master’s is from MIT. Anywhere else, MIT would be considered just about the most prestigious possible place in the world to have got your engineering degree from, but not at Caltech.
There are plenty of other places in the Los Angeles area where it could have been. I think you must be right that she did not go to Caltech, where the boys (and presumably Amy too) are based, but it need not be UCLA (which is rather far away, on the other side of town). USC is a possibility, or the Claremont Colleges (which are just a quick hop up the freeway from Pasadena). It is also not all that far to UC Riverside and UC Irvine.
Except, to my cursory googling, USC and Claremont don’t offer doctorates in microbiology. UCLA does.
How much interaction would physics researchers (they aren’t even professors) have with a microbiology grad student? :dubious:
With that rack? 
Caltech also doesn’t offer a doctorate in microbiology.
I think Sheldon got his Ph.D. via home schooling.
They might. Caltech is a small community.
However, Bernadette didn’t even begin her PH.D. work until some time after she started dating Howard. I don’t recall any reference to her being any sort of student at that time (presumably she was already a college graduate). I think it is pretty clear she did not do her doctorate at Calech. I do not recall ever seeing her lab, although she was dating Howard the whole time.
Yes, it’s explicitly called Caltech, and they even namecheck the Beavers in at least one episode.
When they are in the car on their first date, Howard says to Bernadette “so, Penny tells me you are a graduate student in microbiology.” She talked about lab work a number of times before the episode in which she announced that she’d received her doctorate.
Leonard and Sheldon probably didn’t get their PhDs at CalTech. It’s not uncommon for an academic’s first postdoc to be at the same school as their PhD, nor for a postdoc and a permanent position to be at the same school, but it is uncommon for a school to hire one of their own graduates in a permanent position. It’s sometimes called “academic incest”: You instead want to draw people from other schools, to keep the ideas circulating and fresh.
In some early episodes Sheldon claimed to have two Ph.D.s. He got the first at 16, but I don’t remember any specifics about the second.
I don’t think any of them (except Howard) are in a permanent position. They seem to do no teaching, or virtually none, either undergraduate classes or mentoring PhD. students. If they were faculty they would surely be doing some of both, certainly the latter, on a fairly regular basis. They would also be spending alot of their time worrying about getting grants. As I have argued before, it is most plausible that they (Sheldon, Leonard, Raj, and probably Amy too) are postdocs.* In that case, it is consistent with what you say that they could have done their doctorates at Caltech. Also, although I do not doubt that what you say is the general rule, I suspect that Caltech is the sort of place that might make exceptions to it.
However, I am prepared to take Wesley Clark’s word for it that it has been stated at some point that Leonard got his doctorate at Princeton.
*This i s not quite consistent with the episode where they are competing with each other, and with Kripke, for tenure. That would imply that they are junior faculty, assistant professors. However, I doubt that it is possible to give an entirely consistent account of everything in the show (Amy’s “neuroscience” research that involves smoking monkeys seems pretty dubious, for one example.) The writers just get stuff wrong sometimes. If they had been competing not for “tenure” but for a “tenure track position” (i.e., to become junior faculty) that episode would make a lot more sense in several ways.
Are you sure about the first date thing? I seem to recall that she announced that she was going back to school to get her doctorate at some point when she and Hoard were quite well in to their relationship (although I do not recall exactly which show that happened in). I agree that there was a period while they were dating during which she doing her Ph.D. research, and she sometimes talked about it, but I did not think she was already doing it when they first met. For one thing, she was certainly a waitress at The Cheesecake Factory for quite a while, and it is not at all normal for a Ph.D. researcher in the sciences to have a second non-academic job (unless, perhaps, you are just “writing up” after all the actual research is completed and your funding has expired). A Ph.D. researcher is supposed to be committed full time to academics.
First one was a Ph.D. Second one was an Sc.D.
I am sure. It’s Season 3, Episode 5, "The Creepy Candy Coating Corollary. "
Howard: “So, Penny tells me you’re working as a waitress at the Cheesecake Factory to put yourself through graduate school.”
Bernadette: “Yea.”
Howard: “That’s great. What are you studying?”
Bernadette: “Microbiology.”
(Just pulled up the episode and ff’d to the conversation)