My undergrad quantum mechanics class had 12 people. My professor described the first mid term with my favorite quote tothis day. "If it's solvable it's trivial".
Me: *Physics student taking Differential Equations class* Professor: “Now there is a whole chapter here on solving differential equations by variation of boundaries, but the only people who EVER use this are physicists, so we’re skipping the whole chapter.” Me: ................................ great. 😩
Yeah, in one of my first few classes of thermo and stat mech, my professors was giving background on founders, and was like, "yeah...you'll find that they all seem to kill themselves...*awkward laugh* but I wouldn't worry too much about it". I should've. Stat mech definitely killed me. One of the hardest classes.
For me it was Modern physics just because our professor was from Harvard and he had the highest expectation. we started with 20 students and by finals, there were only 5 students left and only 3 passed.
No offense but your professor sucks. He's a professor so he should've atleast tried to help everyone. What's the point of being a professor if you can't even teach the majority of your students.
@@abhabh6896 It is, but it kinda makes history completely unamusing. Just the other day my friend texted me something like "Dude! Did you know that medieval french court tried and executed a pig for murder? That's crazy!". To which I could only reply "Yeah, what about it? I've seen this court record in full, it makes total sense, if you think about the concept of justice at the time".
@@miobiuscrimson2828 There will always be something you do not know about and well you always have the future to be amused by and the present aswell. I for one find medieval history really interesting but you always have my field , the dark abyss of theoretical physics.
I also found statistical mechanics and thermodynamics challenging, but only for the first time when I learned it (Level 3XXX). It became easier when I learned it at the second time (Level 4XXX). There is actually a famous quotation by Arnold Sommerfeld mentioned by my professor at Level 3XXX:"Thermodynamics is a funny subject. The first time you go through it, you don't understand it at all. The second time you go through it, you think you understand it, except for one or two small points. The third time you go through it, you know you don't understand it, but by that time you are so used to it, so it doesn't bother you any more." And that's true, at least for the first and second times.
Yeah, It's weird to go into a class where the expectation is that you'll get practice solving some problems, but you won't really understand what you are doing by the end of the semester. I took several classes like that, and it drove me nuts desperately trying to understand the material. For thermodyamics, the textbook and instructor weren't much help either.
Honestly, Solid State Physics killed me. Though, that semester, I got the flu twice, and missed 4 of the 16 weeks, so that whole semester was terrible. I agree that Classical Mechanics was hard. It's like, everything you did before was just a nice sample, then you dug deep into the core of what you were approximating. It's like when you have to take Assembler programming in a Computer Science degree. You thought you knew what was going on, and you thought you knew how to code, but then realized that someone did all the heavy lifting for you.
One of the hardest class I had was Advanced Quantum Mechanics. The contents of the class was very interesting and I managed to understand the math and concepts behind it. What made it hard was that the tests and exam covered things completely different from what was discussed in class and assignments.
Intro to astrophysics was a crazy hard class. There was no lecture and the exercises went through so many topics (celestial mechanics, schwarzschild spacetime, quantum ideal gases, nuclear fusion, expansion of the universe, CMB) at record speed. I'm not a physics student, and I also didn't take nearly enough math classes for this.
Quantum mechanics in my undergrad literally felt as hard as a major life tragedy. I tried hard to gain a deep intuition of QM the entire semester and it still feels blotchy.
I remember back in the good ol’ days... our Q.M. Class took 4 hours a night for homework. It started out with about 45 students and ended with the four of us. (Someone asked if my first edition Shankar was my Bible since I was always carrying it and studying from it.) My E&M class wasn’t “easy”, but the material really “clicked” for me (Reitz, Christie & Milford-did anyone else notice how many problems were converted from Gaussian units?) Yndrian’s “Quantum Chromodynamics had just been published and the prof’s didn’t understand the Standard Model any better than we did. The former QM prof had finally developed some respect for us “fantastic four”. Sadly one lady had to leave school because of visa problems. The highlight of the year was a symposium road trip where we met Dr. Carl Sagan. Thanks for your video and the revival of memories of the good ol’ days.
I’m majoring and physics as well and this is my first year of undergrad and I’m having a hard time with classical mechanics as well and damn I love you for making me feel like everyone else struggles with it too 😭🤝
Honestly, I found university physics far more difficult than anything that followed (except maybe advanced E&M - we used Jackson for half the course but that was more than enough to break my spirit). I had a very bad habit of trying to really understand the material and re-deriving everything on my own - unfortunately, this was a very time-consuming process and it often was not what I was tested on. Though I must admit, that mentality served me well when I moved into upper-division courses.
I have the same habit....Like I was reading a book about economic and I stop reading (for now) when the book talk about game theory because I dot nothing about game theory.....the same with classic mechanic, I stop studying to learn variational calculus
Geometry of general relitivity was pretty tough. (Though it was taught as a mathematics course) The prerequisite courses are differential geometry, algebra & differential equations. Recomended to be taken with differentiable manifolds.
Sounds more like a first year graduate level class to me. It's pretty rare to find a mathematical treatment of general relativity in undergraduate physics programs. Then again, you said it was a mathematics course, so I can definitely see it.
I love your videos. I'm graduating with a physics BS this semester too. Best feeling is when you don't really know what you're doing in a 4000 level course but by now you've got that sweet sweet skill to guess a method to solve any problem.
I really think that thermo/stat mech is something that you have to see multiple times to be able to appreciate. I’ve probably covered thermo in depth in 4-5 courses in my undergrad and stat mech in 2 classes (one more in grad school yay!)
my current top 3 are: 1. plasma physics (deriving all the wavefunctions for differect scenarios, and using the momentum, continuity and heat equation. And on top of that; Landau damping) 2. Classical mechanics (should imo be taken later on after the fundamental maths courses) 3. Quantum mechanics (many new concepts, didnt have proper training in differential equations beforehand and SPIN :-P )
Classical Mechanics *is* a fundamental maths course! Well, that’s part-joke: calculus and differential equations are of great help in dealing with it. But (the way the taught me) a whole bunch of maths was derived at the course itself, because it is not generally taught in maths courses.
I really identified with your experience when you said you wished you’d developed your mathematical rigor beforehand. I came into university as a physics major but switched over to majoring in pure math and minoring in physics. Upon taking upper level and more rigorous math courses, I realized that a lot of what I struggled with early on, could be attributed to not knowing the math yet.
Jilal Jahangir it’s a great book to have near as a quick reference, but not a good book to learn from whatsoever. It skips many steps in derivations (most of which are completely non trivial), and usually does not explain why the author is doing things the way he’s doing it. But unfortunately it’s still the most complete book out there. Zangwill comes close (and even has some topics Jackson doesn’t cover at all), but it’s not there yet (maybe next edition?).
Let me first preface this with the following: I got my BS in physics in 2005, so it’s been a long time since my undergrad years. Watching this video had me nodding in agreement, and laughing out loud. There was no RU-vid at the time I was studying physics. I always felt like I was hitting my intellectual limit, if you will, EVERYDAY. There was never a day that went by where I didn’t feel feel inadequate as I was trying navigate through the 30 page solutions for my problem set of six questions 🤦🏻♀️ Needless to say, my best class was actually classical mechanics 😂 My worst? Electricity and Magnetism 😵💫 The one I was not prepared for was my nuclear and particle physics class…and quantum mechanics…both flew over my head, if im going to be honest. I can do the math, but I had no clue what it actually represented. I started getting back into physics recently after the concept of consciousness starting piquing my interesting…which then led to quantum physics…then quantum field theory…and now I had to review everything 🤦🏻♀️ It woke the sleeping giant in me and now I just need to see it through. I appreciate your videos because they’ve given some great tips on good reference books and textbooks to get to help with my sudden resurgence into physics again. Thank you! 😆
I agree. Thermal/Stat-Mech was really demanding. I took it from Dan Schroeder (the guy who wrote the book), it was super interesting and deep but REALLY hard to wrap your head around at times.
I'm currently undergraduate student in third semester and the courses I hated the most until now were experimental physics: classical mechanics, electrodynamics and optics. It's mostly because in the lecture you only get told some special cases and the formulas you are supposed to use in these cases but don't learn why the things are how they are. It's always like: "It's like that, deal with it!" The worst of theses was optics because there were just too many different conventions used for everything. A really annoying example would be Bragg-scattering which sometimes used half the scattering-angle for the Bragg-angle, sometimes the scattering-angle was just the Bragg-angle and once it was pi plus the scattering-angle, and everytime it was totally unclear which convention was used. The exercises were so arbitrary that the only real way to get good marks was knowing the results beforehand and then reverse-engineer what you need to do. Still I was made to think that as an experimental phycisist you need to know the answer before you tackle the problem and then try to make sense of it, which is just not really my beer.
I definitely struggled with QM II in which we covered chapter 5 to the end of Griffith's. The homeworks were super challenging and so were the exams. I also struggeld with EM while it seems a lot of people didn't. Classical mechanics tends to be a very difficult class even for people who started off as physics majors since it's the first "real" physics class that you take.
Correct on classical. That was one of the hardest classes I ever took, everyone thought it was hard, even people good at it. That was literally the moment I saw how smart physicist professors could be. My professor didn't use any notes at all and could answer absolutely any question at all in the book without thinking, or cracking the book. In some of the classes, he would just ask us what we wanted to know. It literally made you(your convention :)) feel stupid. But looking back It wasn't really hard because a lot of things you could visualize, whereas other classes took a lot more effort to visualize problems. However, the main thing I learned was the amount of rigor needed to do other classes.
Lol, procrastinating on my atomic physics take home final by watching video about why atomic physics is hard. Sigh... Excuse me while I go calculate some rubidium. So much goddamn rubidium.
Thermodynamics was challenging, but mainly because we had a massive programming project worth a third of the final grade, and I was just learning basic programming in another class. Having the flu a week before the final didn't help either.
For me it was Computer Organization. Basically how the hardware organizes data flow. Even tho im studying cs I find physics extremely interesting although I don’t want to study it myself. Subscribed.
I guess, thinking about it, my three were all third year: Atomic and solid state physics, astrophysics, and optical physics. I found them particularly challenging because neither my study methods nor mathematics hadn't developed well enough (also missed half a sem due to unfortunate circumstances). I wrote out a 3 page latex doc trying to understand first order perturbation for atomic physics. Took it to my lecturer, and he said, "yeah, all you need is this last bit."
Statistical Mechanics was definitely one of the hardest. I also took Atomic Physics, as an elective, and yeah it was hard. Mad props to you for taking it at the same time you took QM, that's some serious flexing right there. I was doubling in Physics and Chemistry, so I got to take 2 semesters of PChem, which is a lot like Statisical Physics (but with labs).
"I had no idea what I was doing, but I knew how to do it." I'VE NEVER HEARD CRAZY DIFFICULT PHYSICS CLASSES EXPLAINED BETTER, I LAUGHED SO HARD I STARTED WHEEZING AND COUGHING, THANK YOU FOR THIS! 😂 (I laugh because, as a physics and astronomy major, I have felt this EXACTLY. 😂)
Classical mechanics 1&2 were my favorite classes in undergrad. I loved learning the math and principles behind complex problems I could see in the real world. Hardest was taking thermo and solid state at the same time
The math is a bug problem for me, especially when the profs are so up and down. I had my worst prof on advanced calc but my best one in complex variables for example. The only one left is PDEs for me now so I'm hoping I can do better in the physics side. I have thermal and quantum next year plus class mech 2 and statistical as a choice in the final year. I also have electricity and magnetism. Here's hoping I can get into the groove of things as things are so fast paced in my university, you can't catch a breath. I also might have research next fall as well since I couldn't find it in the summer. Wish me luck
Taking classical mechanics right now and I could not agree with your description more. I thought I was so good at classical physics because I knew all the equations and when to use them. Once I got to this class I realized you actually need to derive what you're doing and if you mess up in one place everything beyond it is wrong. Just going to have to forget everything I know and start from the ground up🤷🏼♂️
For my undergrad experience, it was Electromagnetics, Quantum Mechanics, and Mathematical Physics (Math Phys was a 500 level graduate course concerned with real-world applications and solutions of Physics concepts, such as coordinate transformations, Fourier series, Legendre and Bessel functions, quantum mechanics, etc, and also using numerical methods and computers to solve problems that could not be analytically solved.)
You know, I'm not even a physics student (Going to go into business) and I'm here watching you talk about things I'll never study. I just like how you make the videos.
Stellar Astronomy, Quantum, and Cosmology. I haven't taken Thermo/Stat Mec yet but I've had to study special topics of both in 3 of my astronomy classes so, hopefully I'll have an upper hand. We'll see...
I'm not sure how its taught at other schools, but chemical engineering thermodynamics is exactly like he described in this video, and is taken after pchem. They are really different.
Started as a biology major too and currently having classical mechanics. I really, really love this course (I didn’t fully understand the calculus of variations part but still). I think a good teacher is mandatory in that kind of course (without a good teacher I can defo tell it would’ve been a nightmare). Here in Quebec, we do physics 1 and 2 as well as cal 1 and 2 in college before we even go to university (we start uni with classical), and physics 2 was my worst class. I have ptsd from it to the point that I’m extremely scared about electromagnetism next semester.
I took Classical Mechanics straight out of Uni. Physics II, and hadn’t had differential equations yet. The professor was hilariously vague and unhelpful, but it made the homework assignments genuinely rewarding to complete (when we actually managed to complete them). Its made Engineering Dynamics a cakewalk though!
Well, I'm currently in my second semester of physics (first year) and I'm sadly struggling with linear algebra. I'm fine with the physics courses, but it is with the mathematics courses that the professors take way too much time proving all the theorems (with no apparent relation at all to any physics field)
Linear algebra can get super abstract. But honestly, if you can really internalize things like what exactly the relationship between eigenvalues and eigenvectors are, what the significance of a 0 determinant is, completeness, and different vector spaces, you'll get a lot more out of your first course in quantum mechanics. It gives you the tools to look at the schrodinger equation as an eigenvalue problem instead of a second order partial differential equation. Linear algebra is such a powerful tool once you get used to it.
When you get to odes and then pdes. You can skip entire lectures because all they do is talk about applications or theorems or even proofs. Then tests and assignments are so easy and straight forward lol
The biggest issue with a lot of the units I struggled with was that we didn't have just a classical mechanics unit, or just a quantum mechanics unit. Instead they were mixed with other, equally difficult topics, so when it came exam time you needed to be on top of your game for multiple different fields for a single unit. A couple examples of these units are Physics 2A, which was Quantum mechanics (covered the stuff you'd expect, solving and normalising wave functions of single particle systems in various different potentials) and EM waves (EM was went up to pretty complicated electrodynamics, didn't just stick with electro and magnetostatics). Another really tough one for me was called Physics 2B which had solid state physics, special relativity and intro to general relativity and classical mechanics all in the one unit. Each topic on it's own was not too bad, but having to know all of them really well for the exam was tough. The hardest unit I did though was simply called modern optics. I did this in my first semester second year, and it was the first time the unit was running. After the semester was over the university changed it to an honours level unit without changing almost any of the content. For reference, there were 16 people that enrolled in the unit, by the time the exam rolled around, only 8 people showed up, and of that only 3 of us passed. It covered everything from diffraction and interference to holography, non-linear optics and advanced imaging theory (Nano- and Bio-Photonics). On top of all of this we also had to do 6 labs, and write reports for each of them (compared to the usual 3-4 in other units) and do a 3,000 word review paper on a modern optics technique, including at least 20 citations from peer reviewed papers. It was brutal. I scraped through that with a 55% from memory.
Petition to feature Andrew's paraphrases of the 3 Laws of Thermodynamics on the cover page of every text book on Classical Thermodynamics to exist till date.
Andrew Dotson well Andrew i am a Biology major and we are taking some courses in mechanics the module is called "mechanics of a point " (if i explained it right because in Algeria we study only in French)
As Abdelmoula said, why don't you do some lower division mechanics problems. Then, to make the videos more interesting, you could describe the difference of those problems in lower division classes, vs. the big boy classes ("lagrangian and Hamiltonian formalism," your words in a comment to me a couple weeks ago)
Jerry Smitherson Okay so have me solve an easier problem, then show how you could write it in a more sophisticated way so that the transition to “big boy” mechanics is smoother ?
I actually liked thermodynamics, it was my favorite. The statistical mechanics portion was then attributed when I took biophysics and basically combined both and applied them to biological macromolecules
Calculation wise, Classical Mechanic 2, Statistical Mechanics and Quantum Mechanics 2 were brutal but as for difficult concepts to even wrap your head around, Non-Locality was a custerfuck. The words "behaviour space" and "cshs inequalities" still give me goosebumps.
One thing that you talked about that I couldn’t agree more with is the lack of mathematical knowledge. Nothing frustrates me more than a physics course where I am introduced to a math concept that I have never used and expected to pick up on it immediately. Sure, I can memorize solutions but it feels so dirty to use something I don’t have a clue about. I’m trying to plan my math courses in a way that will hopefully prepare me for upcoming physics courses.
I also took a course on series (summation on different series, power series, fourier series, fourier and laplace transform). Really useful on certain physics problems we face on applied physics.
I got an A in Electric Circuits 2 because most of the problems were about modelling mechanical systems into a form of transient RLC circuits in s domain and then solved using Laplace transform. I was good at using Laplace transform then. But I was actually weak at electricity concepts. And I could pass Automatic Control courses, thanks to Laplace transform. :)
My "mathematics for theoretical physics" prof tried to teach us group theory in 3 lectures then has 25% of the final on it going way beyond what we went through in class -.-
For me, it was the very first kinematics course I took as a freshman and the graduate GR course set I took as a senior in undergrad. Oh the PTSD I get from looking at the KK book...
Three most challenging in undergrad ... non-equilibrium thermodynamics (super maths heavy), electromagnetism (Jackson still haunts my dreams), non-linear physics (again, maths).
Astrophysics 2 (cosmology) was the hardest undergrad class I had. I got a B in that class. Subatomic physics is a runner-up, the math was pretty challenging for the level I was at.
1. Graduate Mathematical Physics (Riemmanian geometry, group theory, topology) 2. Quantum Mechanics 2 (Quantum 1 was a walk in the park compare to the second half) 3. General Relativity (I was super into GR but had major senioritis so this class was super hard but only cause I didn’t put the effort in lol)
For me the classes were two: Condensed matter theory - I never managed to wrap my head around phonon-electron/electron-hole pairing, later on Cooper Pairs and how they arise from manipulating creation and annihilation operators algebraically. Also some guy called Bogolyubov had the genius idea of coming up with a hyperbolic rotation (AKA pseudo-rotation) by an operator angle to diagonalize Hamiltonians. Ok. Measure Theory - Now that isn't a physics course per-say but I took it because I love math and I had taken the whole sequence of analysis, algebra and topology classes prior to it. It made me love math even more but for 99% of the class I felt like I was banging my head against a brick wall and mathematicians were pulling arguments out of their behinds (or also known as the uncontably infinite or the infinitesimal). As a physicist, it really made me reshape my thinking.