Is it possible to self study deep physics?

[Liger20]

Hey, I am currently planning on majoring in chemistry, but I am obsessed with physics as well. The school I plan on going to only offers physics as a minor degree, and I can think of many more practical things that I would want to do with chemistry than physics. Still, I like physics more, just learning about physics for the sake of it. The question I’m asking is not one related to what to major in, but rather, if it’s possible to learn deep physics with a chemistry degree. One of my major goals in life is to someday learn the physics and mathematics involved in relativity, quantum mechanics, and maybe even string theory. I have no grandiose visions of being a theoretical physicist or anything (although that would be really cool), I just simply have a strong desire to understand. I don’t care about jobs or money when it comes to this subject, I just love physics. I am willing to study relentlessly, it’s just hard for me to figure out where to start. I am currently in a pre-calculus class, and I have a little bit of background in trig. I realize that I have a very long way to go with the math. I’m not sure that a chemistry degree is equipped with the math needed to understand the above mentioned items, but like I said, this isn’t about degrees or money. Is it possible to self study these things with the right tools? Nothing can keep me from learning and studying this wonderful subject. Could someone knowledgeable in this subject please give me some positive feedback on where I should go from here?
Thanks!

 

[Borek]

If you go chemistry route, try to specialize in quantum chemistry. That'll force you to learn more math than any other chemistry course, and math is the most important prerequisite for studying physics.

 

[Brian_C]

There is a lot of overlap between physics and chemistry. Physical chemistry, quantum chemistry, and solid state chemistry all involve a ton of physics. Quantum chemists probably know more quantum mechanics than your average physicist.

 

[lisab]

Hi Liger20 - I started as a Chemistry major, switched to Physics after taking P-chem.

The other posters are right - you'll have enough general knowledge to understand the basics but you'll want to supplement your math education.

Quantum and thermodynamics translate well from Chemistry to Physics (thermo is called Statistical Mechanics), but if you want to get the full flavor of Physics you'll need to take Electricity and Magetism, too. For that you'll need vector calculus (https://www.amazon.com/dp/0393969975/?tag=pfamazon01-20is a good introduction).

And of course Physics Forums will be a big help!

 

[Liger20]

Hmmm, well maybe I could major in chemistry for now, and minor in mathematics? Then I could take physics classes for all my electives and then major in physics later on? Would that be too much?

 

[physics girl phd]

Hmmm, well maybe I could major in chemistry for now, and minor in mathematics? Then I could take physics classes for all my electives and then major in physics later on? Would that be too much?

I did something pretty similar... I majored in physics and had strong minors in both math and chem. I originally would have double-majored in physics and chemistry (I actually started out majoring in chemistry), except I had some unavoidable lab conflicts about the time of physical chemistry and wanted to take extra math.

Note: if you plan graduate study, there are lots of interdisciplinary graduate programs out there (in physical chemistry or chemical physics -- or materials science, nanotech, etc.).

 

[MissSilvy]

Of course it's possible. I have a friend who is exactly in your situation (except our school offers a physics major, but he decided for various reasons to pursue just chem). It all depends on how disciplined you are and what your expectations on self-studying the subject are. I won't lie; if you think it's going to be all rainbows and sunshine and 'fun stuff', you might be in for an unpleasant surprise. Physics is a lot of problems, some less fun than others, and a lot of the foundational materials (like mechanics and a few other basic area) are boring when you first see them. As long as you are willing to accept and work through this, you'll be perfectly fine.

I'm not an expert on methodology and, only being a beginning physics student myself, I think I'll leave the practical questions of 'how' and 'what can I do?' to other forum members. :) Hope I helped a bit.

 

[calvinuk]

Of course it's possible. I have a friend who is exactly in your situation (except our school offers a physics major, but he decided for various reasons to pursue just chem). It all depends on how disciplined you are and what your expectations on self-studying the subject are. I won't lie; if you think it's going to be all rainbows and sunshine and 'fun stuff', you might be in for an unpleasant surprise. Physics is a lot of problems, some less fun than others, and a lot of the foundational materials (like mechanics and a few other basic area) are boring when you first see them. As long as you are willing to accept and work through this, you'll be perfectly fine.

I'm not an expert on methodology and, only being a beginning physics student myself, I think I'll leave the practical questions of 'how' and 'what can I do?' to other forum members. :) Hope I helped a bit.

How can you find mechanics boring!?

 

[lubuntu]

Kinematics is pretty dry dude.

 

[quantumdude]

Haha, even my first graduate advisor described classical mechancs as "boring as $hit"!

 

[calvinuk]

Kinematics is pretty dry dude.

I love 2D and 3D kinematics, granted it's not the most taxing conceptually, but it's rewarding to solve.

 

[quantumdude]

Quantum chemists probably know more quantum mechanics than your average physicist.

I wouldn't bet the ranch on it. I took a graduate course in quantum chemistry. We started out in familiar territory (postulates of QM, Schrodinger equation, perturbation theory...) but very quickly got into approximation methods that don't even resemble the QM that you see in a physics course (SCF and LCAO methods, just to name two). That's because quantum chemists are most interested in a class of problems that is not solvable: molecular spectroscopy. Given that it's not even possible to get exact solutions for a helium atom, it comes as no surprise that elaborate approximation schemes are needed to get decent approximations to, say, a benzene ring.

I enjoyed the course because I learned how to solve problems that most physicists ignore, but deep quantum mechanics it ain't.

 

[quantumdude]

Hey, I am currently planning on majoring in chemistry, but I am obsessed with physics as well.

Talk to Ben. He got his undergrad degree in chemistry and switched over to physics for grad school.

 

[physics girl phd]

Kinematics is pretty dry dude.

I'll agree here too... who knows how I ever became a physics major with kinematics being the first thing I encountered! I'm much more an EM/optics/materials kinda-gal.

 

[quantumdude]

What's that your cat's reading, Sakurai?

 

[Brian_C]

I wouldn't bet the ranch on it. I took a graduate course in quantum chemistry. We started out in familiar territory (postulates of QM, Schrodinger equation, perturbation theory...) but very quickly got into approximation methods that don't even resemble the QM that you see in a physics course (SCF and LCAO methods, just to name two). That's because quantum chemists are most interested in a class of problems that is not solvable: molecular spectroscopy. Given that it's not even possible to get exact solutions for a helium atom, it comes as no surprise that elaborate approximation schemes are needed to get decent approximations to, say, a benzene ring.

That's my point. Quantum chemists are well versed in the approximation methods needed to describe real world systems. You aren't going to learn any of that stuff in Sakurai.

I enjoyed the course because I learned how to solve problems that most physicists ignore, but deep quantum mechanics it ain't.

This is exactly the type of attitude that drove me away from physics. You can study quantum field theory and Feynman path integrals until you're blue in the face, but you won't be any closer to understanding even the most simple systems, i.e. atoms or molecules. Somewhere along the line, academic physicists developed the attitude that learning "deep" concepts is more important than doing anything practically useful with their knowledge. Is it any wonder that so many of the best students choose engineering over physics?

 

[quantumdude]

That's my point. Quantum chemists are well versed in the approximation methods needed to describe real world systems.

Quantum chemists are well versed in the approximation methods needed to understand molecules. They ignore a much larger class of problems than physicists do (namely solids, nuclei, particles, and quantum optics). They focus on a much, much narrower set of "real world systems" than physicists do. That being the case, I can't see any way to support your claim that quantum chemists understand QM better than an average physicist.

You aren't going to learn any of that stuff in Sakurai.

Not the approximation methods that are specific to molecules, no. But you will learn perturbation theory which is the most important approximation method for physicists. You will also learn the variational principle.

On the flipside of the coin you aren't going to learn any of the approximations that nuclear physicists find useful in a quantum chemistry book.

This is exactly the type of attitude that drove me away from physics. You can study quantum field theory and Feynman path integrals until you're blue in the face, but you won't be any closer to understanding even the most simple systems, i.e. atoms or molecules. Somewhere along the line, academic physicists developed the attitude that learning "deep" concepts is more important than doing anything practically useful with their knowledge.

I don't know where you got that impression but it's wrong. I studied nuclear and particle physics as a grad student. Particles and nuclei are definitely "real world systems".

Is it any wonder that so many of the best students choose engineering over physics?

Is that based on some study, or is it just your personal opinion?

 

[MissSilvy]

Because weight-on-a-spring-on-an-inclined-plane problems make me want to die, that's why :P

Is it any wonder that so many of the best students choose engineering over physics?

Most of the engineering student I've encountered are significantly more mentally-deficient than physics students. I have no idea where you get your sources. The reason I chose physics over engineering was because so many of the engineers had no idea how to think creatively beyond a few tired designs. They had NO idea what was going on, except that to calculate such and such, you stick fancy numbers into this formula and out comes some answer. How do you know that's the correct formula or that another one wouldn't be better? "The book/professor says so."

 

[calvinuk]

Because weight-on-a-spring-on-an-inclined-plane problems make me want to die, that's why :P

Ha this is probably why nobody wants to study Physics in the UK.

At A-level this is pretty much what we study in Physics and Further Maths.

 

[quantumdude]

OK, let's not start bashing people because of their majors. I have degrees in engineering and physics and I know from firsthand experience that both fields have their fair share of dummies.

 

[Borek]

I know from firsthand experience that both fields have their fair share of dummies.

Probably even more dummies between chemists. At least in my firsthand experience

 

[ronaldor9]

Probably even more dummies between chemists. At least in my firsthand experience

Hahahahah best thing I've herd all day!

 

[alxm]

Maybe I can be of assistance here, since it's the field I'm in.
First off, you've got quite a lot of options, at least in terms of department names! There's "Chemical physics", "Physical chemistry", "Theoretical chemistry", "Quantum chemistry" and most recently, "Biophysics".

This is all essentially the same stuff, and you wouldn't need to pick one before you get to the postgrad level. Either you get into the field through chemistry and take extra math and physics, or study physics and take extra chemistry.

I wouldn't say that your average Quantum Chemist understands QM better than your average physicist. Because, your average Quantum Chemist is your average physicist. Most people in Quantum Chemistry have a physics background. Not that it really matters - you'll likely have no problem finding ones with a chemistry background with better QM knowledge than others with a physics background.

That's because quantum chemists are most interested in a class of problems that is not solvable: molecular spectroscopy.

I wouldn't say that. Some work with that, and a lot of "Atomic and Molecular Physicists" work with QC methods in conjunction with experiment. But most quantum chemists work with method development, that is, improving the approximations. (and in that area, it does border on theoretical physics) Those who work with applied theory tend to be more interested in bonding, reaction mechanisms, and that kind of stuff. But it depends of course on your interests. You also have heavy-element QCists who work with relativistic theory. Spectroscopical stuff often requires time-dependent theory. Then there's DFT, which originated in Solid State Physics but is now the most popular method in QC.

Anyway, apart from QC you still have the vast interdisciplinary field of spectroscopy, the spanking-new field of femtochemistry (the theory of which is pretty intense, or was for me at the time), circular dichroism spectroscopy of biomolecules (which I've never quite checked out the details of), NMR spectroscopy (calculating the nuclear spin density matrix time evolution over various RF pulses). Then there's 'classical' physical chemistry like the adsorption of atoms/molecules onto substrates, statistical mechanics, and stuff like that, but also new stuff like physical modeling of large biomolecules.

So in short, it's a huge field, and there's lots of stuff to do for chemistry-loving physicists or physics-savvy chemists.

 

[George Jones]

One of my major goals in life is to someday learn the physics and mathematics involved in relativity, quantum mechanics, and maybe even string theory. I have no grandiose visions of being a theoretical physicist or anything (although that would be really cool), I just simply have a strong desire to understand.

This is possible, but it requires a consistent effort that, without the structure and deadlines of formal courses, is hard to maintain. Even with the best of intentions, picking up a job, spouse, kids, car payments, mortgage payments, etc. make life so harried and hectic that other stuff tends to get lost in the shuffle. For one father's perspective (probably worse for mothers), see

http://www.cnn.com/2009/LIVING/personal/03/09/p.dads.want.out.house/index.html.

But it is possible. In fact, I currently am working on a webpage of short comments about technical references for cosmology, relativity, quantum mechanics, elementary particles and quantum field theory, and string theory that have such scenarios in mind.

I have definite ideas for references for the above topics, but I would like some suggestions for background material. See,

https://www.physicsforums.com/showthread.php?p=2110651#post2110651.