(October 7, 2022 at 11:45 am)polymath257 Wrote: If you want to learn physics, start with math. Go at least through differential equations and linear algebra.

Then get a good engineering physics textbook and read it. After that, you can start on quantum mechanics and special relativity. Don't expect to do general relativity until you have had more math (at least multivariate calculus and some more advanced linear algebra involving tensors).

Being able to do physics requires 2 things:

1) Math, as polymath says.  If you can't do the math, you can't say you fully understand a physical concept.

2) An ability to go from the problem to the mathematics.  This is a synthesis of knowledge.  I do it by visualization, and by intuitively breaking down the problem into its fundamental pieces.  This is the more fun part (sorry, polymath)

(October 7, 2022 at 5:07 pm)HappySkeptic Wrote:

(October 7, 2022 at 11:45 am)polymath257 Wrote: If you want to learn physics, start with math. Go at least through differential equations and linear algebra.

Then get a good engineering physics textbook and read it. After that, you can start on quantum mechanics and special relativity. Don't expect to do general relativity until you have had more math (at least multivariate calculus and some more advanced linear algebra involving tensors).

Being able to do physics requires 2 things:

1) Math, as polymath says.  If you can't do the math, you can't say you fully understand a physical concept.

2) An ability to go from the problem to the mathematics.  This is a synthesis of knowledge.  I do it by visualization, and by intuitively breaking down the problem into its fundamental pieces.  This is the more fun part (sorry, polymath)

Different types of fun.

The universe may not be locally real, but it’s locally real enough.

Boru

(October 7, 2022 at 5:07 pm)HappySkeptic Wrote:

(October 7, 2022 at 11:45 am)polymath257 Wrote: If you want to learn physics, start with math. Go at least through differential equations and linear algebra.

Then get a good engineering physics textbook and read it. After that, you can start on quantum mechanics and special relativity. Don't expect to do general relativity until you have had more math (at least multivariate calculus and some more advanced linear algebra involving tensors).

Being able to do physics requires 2 things:

1) Math, as polymath says.  If you can't do the math, you can't say you fully understand a physical concept.

2) An ability to go from the problem to the mathematics.  This is a synthesis of knowledge.  I do it by visualization, and by intuitively breaking down the problem into its fundamental pieces.  This is the more fun part (sorry, polymath)

Physicists are like plumbers. If I need one, I can hire one.

Boru

(October 7, 2022 at 11:45 am)polymath257 Wrote: If you want to learn physics, start with math. Go at least through differential equations and linear algebra.

Then get a good engineering physics textbook and read it. After that, you can start on quantum mechanics and special relativity. Don't expect to do general relativity until you have had more math (at least multivariate calculus and some more advanced linear algebra involving tensors).

I started failing college at the time that I was taking differential equations and abstract algebra. I rather liked differential equations even though I didn't get far. My main handicap is never having memorized the trigonometric identities. I'd have to restart at Calc I, but my progress would likely be swift. I always found the concepts easy to absorb. In two years I will qualify for basically free college classes. I'm sure that I could handle 15 credits a quarter without any real difficulty. I'm close to the U and so travel time is minimized.

(October 7, 2022 at 6:33 pm)Angrboda Wrote:

(October 7, 2022 at 11:45 am)polymath257 Wrote: If you want to learn physics, start with math. Go at least through differential equations and linear algebra.

Then get a good engineering physics textbook and read it. After that, you can start on quantum mechanics and special relativity. Don't expect to do general relativity until you have had more math (at least multivariate calculus and some more advanced linear algebra involving tensors).

I started failing college at the time that I was taking differential equations and abstract algebra.  I rather liked differential equations even though I didn't get far.  My main handicap is never having memorized the trigonometric identities.  I'd have to restart at Calc I, but my progress would likely be swift.  I always found the concepts easy to absorb.  In two years I will qualify for basically free college classes.  I'm sure that I could handle 15 credits a quarter without any real difficulty.  I'm close to the U and so travel time is minimized.

The first diffeq course is usually not a proof class. Abstract algebra is, though. And figuring out proofs is almost always a hurdle. if you go far enough, the representation theory of groups is useful in symmetry aspects of physics and is a common way to find conserved quantities via Noether's theorem. In diffeq, make sure you have a class that does power series solutions and, if you can, covers a bit of partial differential equations.

I can recommend good physics books once you get past the calculus based engineering physics. Electromagnetism is another key topic.

(October 7, 2022 at 8:17 pm)polymath257 Wrote: Electromagnetism is another key topic.

A linear algebra class offered by the math department seems to be one of those classes few physics majors take. Not sure why. It's a great intro to proofs. My alma mater also offered a class that used Dennis Sentilles' book for a class that focused primarily on how to "do" proofs. I got a tiny bit of series solutions and Fourier Transforms at the very end of my DE class. I went to work in electromagnetic propagation topics right out of uni. I didn't get enough of what I needed at uni. Antenna radiation propagation and scattering is full of it. I got out of the antenna business 22 years ago, and don't remember much. I remember even less about quantum mechanics, which I never used.

(October 7, 2022 at 9:36 am)Angrboda Wrote: I've decided to start learning Hmong and Spanish.  Maybe it's time I acquired a decent grasp of physics as well.  No time like the present to learn something new.

Something tells me you would have no trouble at all. ❤️

(October 7, 2022 at 8:40 pm)Fireball Wrote: A linear algebra class offered by the math department seems to be one of those classes few physics majors take. Not sure why. It's a great intro to proofs. My alma mater also offered a class that used Dennis Sentilles' book for a class that focused primarily on how to "do" proofs. I got a tiny bit of series solutions and Fourier Transforms at the very end of my DE class. I went to work in electromagnetic propagation topics right out of uni. I didn't get enough of what I needed at uni. Antenna radiation propagation and scattering is full of it. I got out of the antenna business 22 years ago, and don't remember much. I remember even less about quantum mechanics, which I never used.

That's odd, as linear algebra figures prominently in Quantum Mechanics, and also in tensor calculus. One good book is, "Mathematical Methods in the Physical Sciences" by the late Professor Mary L. Boas. Her son, an academic mathematician, keeps an errata of his mother's book.