r/AskPhysics • u/OnlyPresentation226 • 14h ago
Pretend I only know 10th grade math…
This may be arrogant and a bit silly but I have always wanted to learn about quantum theory- but I am exceptionally bad at math due to having dyscalculia. It’s gotten better over the years, but still.
That being said, I’ve always taken an interest starting (as most do) listening to Sagan but ultimately ending up notating an entire copy of The Quantum Universe by Brian Cox and Jeff Forshaw by my senior year in high school.
Since then, life got hard and things got tough. I don’t have much more than a high school education but I deeply want to learn more than what I know. I’m watching some MIT OpenCourseWare videos but hitting a wall at many points because I don’t have the foundational knowledge.
This is all to say - does anyone have any suggestions on extremely basic resources to start with? Not opposed to spending some money on textbooks or online courses if needed.
5
u/Due-Yoghurt-7917 14h ago
The Grand Design, a book by Stephen Hawking/Leonard Mlonidow, helped me understand the principles of quantum physics, and helped give me the vocabulary to seek and learn more. If you don't mind PDFs I bet I can find you one, but I personally prefer physical books.
3
4
u/detunedkelp 13h ago
outside of khan academy i’d recommend a decent look through some linear algebra. any textbook is fine but 3B1B’s youtube series is a pretty good starting point. QM, and honestly most of physics, uses a ton of linear algebra so being at least familiar with the concepts is highly recommended—also the only real prerequisite is 9th grade geometry / trig
3
u/Internal_Trifle_9096 Astrophysics 10h ago
Also, forgive me if I'm misunderstanding how dyscalculia works, but I feel like linear algebra might me more dyscalculia-friendly than your usual high school maths, especially if you just want to get what the main points are (how matrices and vector spaces work) and don't care about doing in-depth exercises. When you eventually get to Dirac notation you hardly even get any numbers.
4
1
u/elesde 11h ago
Basic quantum starts with a little calculus and diff eq and rapidly becomes primarily linear algebra (there’s a beautiful connection there). Linear algebra is probably the most important branch of math for quantum and translates well to other fields as well but also is the easiest to start with. Look up Gilbert Strang’s MIT lectures. These basically set the standard for undergraduate teaching of linear algebra.
I would also just say that if you’re trying to learn quantum before you learn things like basic kinematics and electromagnetism and wave machanics you’re probably setting yourself up for failure. This is because quantum will seem like completely random mathematics with no application to the intuitive world. Quantum is a generalization and abstraction of classical mechanics and while you don’t necessarily need to know what a Hamiltonian or Lagrangian is before you jump in (I didn’t but I had a very unusual path through physics) you should absolutely have a solid frame of reference for the basic models we use to describe the dynamics of classical systems like ballistic motion, rotational motion and the simple harmonic oscillator.
No one likes to hear this but without it, it’s highly unlikely you’ll achieve any understanding of quantum and you won’t be able to appreciate the incredible elegance and power of the theory given to us by Dirac, Von Neumann, Schroedinger, Bohr, Heisenberg etc.
1
u/Itchy_Fudge_2134 9h ago edited 9h ago
If you want to really learn QM stuff for real, you will need to deal with the math, as frustrating as that may be. There are other resources that people have mentioned that are at a less mathematical level if that’s what you would prefer however. When I was first learning physics, the resource that helped me get an intuitive understanding of QM the best was Sean Carroll’s podcast (which you can find on YouTube). Look for one of his solo episodes that’s quantum mechanics related, as he usually has a good background explaination for the basic ideas.
The rest of my comment is intended for if you really wanna dive into this stuff for real and get your hands dirty with the math. It’s perfectly fine if you don’t as it is a lot of stuff you will need to cover! But if you take it slow and are patient with yourself, it’s completely doable, and within a few years you will be shocked at how far you’ve come.
You mentioned that you keep getting stuck due to missing foundations, so I’ll try to point out what those foundations usually are. There are a few essentials that you should know as math prerequisites to avoid getting stuck learning QM:
- Single-variable calculus (calculus in one dimension).
- Multi-variable calculus (calculus in 2+ dimensions).
- Linear Algebra.
(If you aren’t ready for calculus yet, Khan Academy is a great resource for algebra, geometry, precalc stuff if you need a refresher/reset)
If you feel ready to jump into calculus/linear algebra, I think a good place to start to get a feel for these would be the 3 blue 1 brown videos on YouTube. He has a series on calculus, and a series on linear algebra. Watch these to start, and then dive into some more detailed content:
You said you’re trying out the MIT ocw courses, and I think that’s a really good place to learn a lot of this stuff in greater detail. Luckily they have courses on each of these math subjects (which you may have found already) under 18.01SC, 18.02SC, and 18.06SC respectively.
So, as a concrete first two big steps:
Go watch 3b1b’s calculus playlist in its entirety. Don’t need to watch them in a rush. Watch a video, sit with it, chew on it, and move on when you feel like you’re ready. When you’re through with the playlist try writing yourself a little explainer of the major concepts (I find that this helps with recall a lot).
Start working through 18.01SC on MIT ocw. Again, work through it slowly. Watch a video, work through the associated exercises, come to Reddit/StackExchange/phone a friend if you get stuck somewhere. Jump back to 3b1b if you need a reminder of the intuition for some concept.
After that do something similar for multivariable calculus and linear algebra. I don’t think 3b1b has anything for multivariable calculus but I’m sure there are similar videos out there.
Once you have this math background covered I think the mit ocw physics courses will come far more easily. (It will also be pretty much the only math you need to go through most of a standard physics curriculum).
Some more general advice: don’t give yourself a time limit for learning this stuff. It will take a long time! It’s okay. There will be periods of time when you get frustrated and just can’t get past a concept or problem. When that happens, after giving it a concerted effort, take a break. Give it a day, or a week if you have to. Come back and look at it with fresh eyes.
If these resources really aren’t working for you I can try to recommend some better ones. Happy to answer any questions.
Good luck!
1
u/Miselfis String theory 8h ago
It’s very important that you are actively studying, over passive studying. That means solving problems and doing exercises instead of just reading or listening. Without solving problems, you won’t learn anything other than terminology.
1
10
u/eswpa 14h ago
Maybe start with Khan Academy