* This joke is for everyone who’s ever loved (or hated) the quantization of total angular momentum, J. The z-component of total angular momentum is denoted by Jz.
For a given j (the quantum number that characterizes the magnitude of total angular momentum as J=ℏ√j(j+1) ), Jz can have 2j+1 different values.
* In case you don’t really follow pop-culture, the joke refers to Jay-Z’s song “99 Problems,” which has the infamous chorus line: “I got 99 problems but a bi*ch ain’t one”.
The semester started last week. I am again teaching a junior/senior elective for majors and it looks like it might be a rough semester.
The course I am teaching follows a basic, required course in the major. I find the students are poorly prepared, more poorly than the class I had last semester. The students are quiet and look positively terrified. I know it takes a little while for people to warm up and start answering my in-class questions, so that will come with time. But I am being quite alarmed by all the things that they say they have never seen before, because, if that’s true, then I have to significantly rethink the class. Sure, I suppose they might be fibbing, but I do believe think most of them have simply never seen the material or, if they have, then it really didn’t stick at all and they genuinely don’t remember it.
Last week and this week, we are reviewing the material from the previous course, and it’s going very slowly. I may have to take more time simply to get them up to where they would actually need to be, which means cutting out some of the new stuff.
Also, the lack of facility with math always rears its ugly head, but at least that’s not particularly surprising. Any physical science field that requires a lot of physics has to be taught math really rigorously, and the math department does a very good job. The problem is that, owing to a recent
idiotic progressive change in the curriculum for our major, which is supposed to give the students more flexibility to freely choose easy courses outside of the major customize their program of study, some important formerly required math courses have now become electives (e.g. how can linear algebra and differential equations not be required just fuckin’ blows my mind) and now many students elect not to take them. Also, many of the required math courses are mismatched in timing with the relevant courses in the major.
Perhaps more importantly, on top of pure math, the next layer is often missing, and that is the layer where the students are taught physics while using the math tools. This is where they should simultaneously be taught how to build their intuition about the physics with the help of math (math is your friend, people!!!) and how to better understand the ability of math to capture the physical world. What we need are slower-paced calculus-based physics courses and less jam-packed syllabi in the lower-level courses for our major. The way physics for non-physicists courses are taught right now is woefully inefficient: there is too much material in each one of these courses, everything is only touched upon, and the kids retain absolutely nothing. It’s a complete waste of time. Considering that many students haven’t had physics as a standalone subject until college, maybe I shouldn’t lament but should be in awe that the kids have as much proficiency as they do.
People say that we discourage our physical science majors by throwing so much math and physics and chemistry at them when they join the university. That it’s boring and kills their natural creativity and that we should get them more chances to design right away and whatnot. First, if you are going to be a professional scientist or engineer, you need to know that stuff. There is no way around it. You cannot do/create/design anything new and have it work without being able to recognize whether or not it violates the basic laws of nature. So there is no doubt in my mind that a solid foundation in basic math, physics, and chemistry is the core of physical science education. I don’t know how we make it less boring and more appealing — I thought all of it was fascinating to begin with. There are freshman design courses sprouting all around the country, many with a humanistic component, where kids are taught to interface with the communities and solve actual existing problems. I think that is great and helps motivate a lot of kids, but we can’t forget that in order to be independent scientists and engineers we have to give them a lot of basic science tools — sure, it’s cool to make a product for someone in the community as a freshman, but don’t forget that there was an instructor there to catch the (often obvious) fallacies in the many iterations of the design. For most kids, we are not stifling their unique unadultarated genius with these basic courses; we are giving them the tools so they would be able to work independently to express their creative ideas once they have their diploma in hand.
But perhaps what would help more than anything is somehow magically undoing the years of programming in middle and high school that tell kids math is stupid and boring and useless, and that only hopeless nerds like science and engineering…
This is a cute movie on the famous double-slit experiment, featuring a caped and bespectacled superhero Dr Quantum. I show it in class to my undergrads as they first get exposed to quantum mechanics. Enjoy!