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So you want to learn physics (2021)

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Re: So you want to learn physics (2021)

#111

Post by blueblimp »

BenFranklin100 wrote: post #68
ak_111 wrote: post #40

Earlier quoted context omitted.

That is some dedication, well done. Interesting to know more about your career and where this lead to if you continued down the physics path.

I went on to earn a doctorate in biophysics and then began a career developing instrumentation for biomedical research. While I no longer work directly in the field of physics, the physical intuition and reasoning abilities honed by a physics education has allowed me to successfully lead teams consisting of electrical and mechanical engineers, while serving as the liaison to biologists and doctors. I regard a physics…

> I regard a physics education as a modern-day ‘liberal arts’ technical degree.

Some anecdotal evidence for this:

https://www.dwarkeshpatel.com/p/dario-amodei#details

> Dario Amodei: We have generally found that if we hire someone who is a Physics PhD or something, that they can learn ML and contribute just very quickly in most cases.

Re: So you want to learn physics (2021)

#112

Post by tnecniv »

simonh wrote: post #99
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Idiot who transferred from physics to computer science after year 1 here, so please make allowances. But all of those phenomena are emergent. Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody c…

You could say that about a lot of topics. Heck you could say that chemistry is just an emergent phenomenon of physics.

The benefit of taking such a class or reading such a textbook is that these things have been studied extensively, we have good models for them, and it is useful to know because people are still doing fundamental research on it to this day or working on phenomena that are closely related.

Re: So you want to learn physics (2021)

#113

Post by tnecniv »

meristem wrote: post #81
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Do you have text/other sources suggestions for this? I agree with you, would like to learn more.

I don’t know much about continuum mechanics (unless you count stat mech but I wouldn’t), however Goldstein has a few chapters on the topic that might serve as an introduction

Re: So you want to learn physics (2021)

#114

Post by tnecniv »

BeetleB wrote: post #108
shanusmagnus wrote: post #85

Earlier quoted context omitted.

Like another commenter, I'm curious what drove you to this. Seems like clearly A Good Idea I Could Have Benefited From, but my attitude was always: I finished the class, whatever I need to learn through application, life will point me toward. Yet I wish I had done something similar to what you did. What gave you the impetus?

> I finished the class, whatever I need to learn through application, life will point me toward. In math/physics, it often won't. Solving lots of problems serves two particular purposes: To really solidify the concepts in your mind so you won't forget, and ensuring you learn the techniques and not just the knowledge. For the former, you may find yourself in the position where you find yourself way over your head, and…

Plus, at various times, I’ve had to revisit things I learned years ago and ended up understanding it much better because I could connect it to a swath of things I hadn’t learned the first time I saw the material.

Math and its applications are a contact sport. You don’t truly appreciate it until you try to use it yourself.

Re: So you want to learn physics (2021)

#115

Post by tnecniv »

ecshafer wrote: post #61
ChuckMcM wrote: post #35

Earlier quoted context omitted.

Totally 100% with this. When younger I thought I could read the material and say "Oh, okay that makes sense I understand this." Only to fail miserably when on a test or somewhere I had to apply what I "knew" and realizing I didn't actually know it. I lean strongly toward autodidacticism and learned that if I could solve problems with the technique then I knew it.

My calculus 1 professor gave the advice that the best way to study is to do every problem in the book, then go and get another book and do every problem in that book, and keep doing that until you look at a problem and know exactly every step to do immediately.

There’s certainly fields of math where I’ve seen a twist on the advice. Differential geometry, for example, is a big field with a lot of notation. Different textbooks end up using very different notations and covering non-overlapping sections of the field. Therefore, the advice I got was to not just do the problems, but translate the definitions and theorems into a unified notation that you feel is natural.

Re: So you want to learn physics (2021)

#116

Post by wanderingmind »

meristem wrote: post #81
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Do you have text/other sources suggestions for this? I agree with you, would like to learn more.

The best book I came across is this https://www.amazon.com/Continuum-Mechanics-Foundations-Appli... It has a slightly solid mechanics bent, but the fundamentals are the same for fluids and solids (conservation laws, tensor formulation)

Re: So you want to learn physics (2021)

#118

Post by ayakang31415 »

amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

The undergraduate Physics program is, in my opinion, heavily influenced by the working physicists in the field. Lots of physicist who work in fundamental physics is either particle physicists or work with models that are in particles. Those are the ones who teach physics in undergrad.

Re: So you want to learn physics (2021)

#119

Post by dhosek »

simonh wrote: post #99
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Idiot who transferred from physics to computer science after year 1 here, so please make allowances. But all of those phenomena are emergent. Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody c…

Reminds me of a student sketch from my days in nerd school, parodying Star Trek. A student dressed as one of the physics professors demonstrated that FTL travel was impossible, causing the Enterprise’s warp drives to stop functioning. It was fixed when Scotty said, “Wait, I’m an engineer: I don’t need to understand physics!”

Re: So you want to learn physics (2021)

#120

Post by consilient »

simonh wrote: post #99
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Idiot who transferred from physics to computer science after year 1 here, so please make allowances. But all of those phenomena are emergent. Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody c…

> Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering.

1. The boundaries between disciplines are where they are in part by historical accident, and in part because that's what the people working in them find useful - there is no actual fact of the matter.

2. We don't actually know the underlying microprocesses of anything. Effective theories are all we have, and there's no fundamental difference between an effective theory for the vacuum (if it is a vacuum) and one for, say, the bulk of a semiconductor.

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