/r/PhysicsStudents

A place for physics students of any level to discuss the intricate profoundness of the universe.

This subreddit is aimed towards undergraduate and graduate students pursuing a PhD in physics. It is not as serious as r/physics (although papers and articles are encouraged!) and not strictly for physics help like r/askphysics. Just a community of physics students wanting to share info, asking for physics help or looking for advice!

**Related Subreddits:**

/r/Phys (papers and blogs only)

/r/PhysicsStudents

0

- I would appreciate it if you could recommend any free videos about nucleon decay that you think I should watch.
- I am interested in learning about both theory and experiments.

2 Comments

2023/12/08

05:44 UTC

05:44 UTC

9

I'm trying not to fail my final as it's worth a lot which will determine if I pass the class or not there. My issue is because i can't understand in depth the concept which leads me to getting bad grades and I wish to know what I'm I suppose to do in order to understand the concept in depth in order to not fail specifically because it's hard for me to understand what to do when there's only letter and no number in the question.

3 Comments

2023/12/08

05:25 UTC

05:25 UTC

0

And what’s the best explanation of this? Including the last part where the ball crash the little wall.

2 Comments

2023/12/08

04:42 UTC

04:42 UTC

1

3 Comments

2023/12/08

04:15 UTC

04:15 UTC

1

2 Comments

2023/12/08

04:09 UTC

04:09 UTC

0

I am having a hard time grasping Spherical harmonics. Does anyone have a good reference the think might help.

I have currently read Jackson and Griffith

1 Comment

2023/12/08

03:31 UTC

03:31 UTC

1

1 Comment

2023/12/08

02:53 UTC

02:53 UTC

1

I´m trying to do a symulation about the Arago-Poisson spot. I know that I can approach this problem using Fresnel-Kirchhoff equations for diffraction. However I have no idea how to use those to model a spherical object. Does someone knows where I can find information about this?

0 Comments

2023/12/08

01:07 UTC

01:07 UTC

0

1 Comment

2023/12/07

23:57 UTC

23:57 UTC

11

I'll be enrolling in college next year and I have to choose whether I want to study "normal" physics or astronomy. While I absolutely adore the astrophysics we've had in school so far (prob my favorite subject alongside electromagnetism), from what I've heard and seen, astronomy has *a lot* of coding--something that I'm not that big a fan of.

I realize I'll probably have to learn to code for just ordinary physics somewhere down the line as well, but I definitely do not want to do it as a primary function of my job.

I also fear that if I study astronomy I'd just be unnecessarily specializing myself way too early on in my career compared to if I just studied physics. Potentially making it so that I won't come across fields that I might like even more.

But anyway, to people who study astronomy, is it correct that astronomy has a lot of coding and what is it like compared to plain ol' ordinary physics?

5 Comments

2023/12/07

23:27 UTC

23:27 UTC

1

I’m curious how many of us here are autistic? Or think they might be? I got diagnosed as an adult. Never thought I was honestly. Just shy and weird. A lot of the big names in our field were/are high functioning autistic.

0 Comments

2023/12/07

21:31 UTC

21:31 UTC

8

For context on why I say "learn" in the title, I took my Universities. LA and differential equations course, which covers both topics. However, LA sections were cut out to add differential equations topics. So, I'm worried I was not introduced to all the necessary LA topics. Below are the LA topics in the order that we covered them:

- Chapter 4: Systems of Equations and Matrices
- Introduction to Systems and Matrices
- Gaussian Elimination
- Row-Echelon Form and Rank
- The inverse of a Square Matrix
- Determinants by Cofactor Expansions

- Chapter 6: Linear Transformations
- Eigenvalues and Eigenvectors

- Chapter 7: Systems of Differential Equations
- Eigenvalue methods for Linear systems

*Note: the chapters containing the subpoints do not represent what we learned. What we actually learned are the subpoints, not everything that would be relevant to those broader topics. Additionally, this was a very method-based course: no theory was taught, only how to solve the problems.

So, are there any other topics that I should review, or would knowing everything listed here be satisfactory?

4 Comments

2023/12/07

20:42 UTC

20:42 UTC

2

How exactly does the ball affect the rod in this problem?

1 Comment

2023/12/07

17:39 UTC

17:39 UTC

7

So I graduated in May, and, rather than go straight to grad school, I turned down the offers and decided to take a year to invest in new skills and work on projects I never had time for. I’m now half-way through the investment year, and as I work on grad school applications I’ve ran into an issue I can’t seem to avoid—experiment vs theory. I love both; I absolutely adore the intricacies and challenges that they offer. I don’t know which to choose. I love group theories, differential forms, programming, data analysis, interpretation, and modeling, but I also love hands-on work, real-world applications, experimental design, and working with the real world. In my mind, splitting physics into these two sections has been overall detrimental, because science is specifically the unity of the two (observation and modeling). But that’s beyond the point.

My main issue is that I keep second-guessing myself as I apply for these different programs. I’ve recently been most interested in solid state physics, quantum materials, and biophysics, because they seem to be very interdisciplinary and combine a lot of experiment and theory. But then I’ll read about some professor’s work in, for example, quantum information theory or the AdS/CFT correspondence, and I feel like I might be focusing on the wrong fields. I feel like this line between theory and experiment, and all these gaps between fields, are being imposed on me, and I’m not sure how to take it. I guess it’s just not how my brain likes to work.

I know it’s silly—“oh no help me I’m interested in too much stuff”—but it’s genuinely starting to stress me out, so I figured I’d ask for advice. Should I just suck it up and see what sticks once I’m actually in a program? Or does someone have a different take?

5 Comments

2023/12/07

02:13 UTC

02:13 UTC

2

0 Comments

2023/12/07

01:50 UTC

01:50 UTC

5

this is what I have tried so far, up top you can see the figure, that is all the information the problem provides, aside from the fact the system is in equilibrium, it says we must find angles alpha and beta, but i always get stuck at that point

3 Comments

2023/12/06

23:44 UTC

23:44 UTC

5

Hello all

Next semester, I am currently enrolled in intro EandM w/lab, intro thermo and optics w/lab, diff eq, and a physics elective which i know isn’t time intensive. Disregarding others sources of lost time (lol) that I haven’t mentioned, how time consuming would you say the first three courses are in conjunction with one another? I just recently switched into the physics major recently, from chemistry.

Thank you soldiers

6 Comments

2023/12/06

22:09 UTC

22:09 UTC

4

I'm involved in a project that demands some superficial understanding of calculus-based Physics. Since AoPS only covered up to single-variable Calculus (with a strong emphasis on methodology), I'd like to know if this is enough to understand the whole mathematics presented in those traditional calculus-based textbooks such as the one mentioned.

For those who don't know AoPS contents, their Calculus book mostly introduce concepts such as limits, continuity, derivatives, integrals, power series, plane curves and differential equations. It's also a short 300 pages book, so it's very different from the traditional single or multivariable Calculus textbooks.

4 Comments

2023/12/06

22:07 UTC

22:07 UTC

1

A cylindrical piece of a pine trunk has a mass of 66.7 kg. What is the radius of this trunk? Density is 0,54 g/cm3.

These are the only informations given. Am I stupid or im missing something. To find “l” i need “r” and to find “r” i need “l”. Im in paradox can anyone help me pls.

Somehow professor found l(length) but l is not given in question. But how?

3 Comments

2023/12/06

20:09 UTC

20:09 UTC

3

I already finished part (a) simply using integration by parts. Does anyone know how to do part (b) using Gauss's theorem?

2 Comments

2023/12/06

19:48 UTC

19:48 UTC

4

I just have so many little questions regarding applications and I just don't know who to ask questions like this. I'll list a few of my major questions below, but if anyone has any experience applying to grad school or being on admission staff I'd love to chat about it so please feel free to reach out!

To what extent should I elaborate on my "past academic work?" Is it just my research experience, should I talk about classes I have taken? How detailed should I be in explaining my research experience? Should I focus more on what equipment and software I have used or more on the skills (hard skills or soft skills or both?) I have acquired along the way?

What should I put when schools are asking me what other schools I am applying to? Should I leave it blank or would that hurt me in some way?

I have a lot of prominent "hobbies" you could say that play a big role in my life and my extracurricular activities, but should I include this in my CV. I've been a professionally working photographer for 6ish years now and I was very involved in student media all through college(magazine work, yearbook, ad agency, etc) and have even held leadership positions. Should I mention these even though they have nothing to do with my major?

I have plenty more questions for anyone willing to discuss. Any help is so very appreciated!!!

5 Comments

2023/12/06

19:33 UTC

19:33 UTC

3

This was a long question where we derived E(x.t) and B(x.t) and then Poynting Vector S(x,t). Then we have to get the Power Radiated per Solid Angle which has to come out equal to the equation in the second image. I got to the equation in the first image by using the accelleration field of Electric field but i dont know how to further simplify to get the final solution.

How to I get from this

The circle is a dot product and p is a a time-dependent dipole moment p(t) at retarded time p(t-|x|)

To this:

I dont get how it can be simplified to this ;-;

Also if somone could outline the steps for the next part where we have to integrate the power radiated over solid angle over all of space that would be great!!

4 Comments

2023/12/06

18:17 UTC

18:17 UTC

6

I graduated university this year with a degree in kinesiology. I now realize that I do not want a career in any kind of healthcare. I never took a physics class until my senior year, in which I took 2 intro classes. These physics classes challenged me in a way no other subject has, and while I found it difficult, I enjoyed actually being challenged for once. I now want to further study physics, but I don’t think I could go straight into a masters/phd with a kinesiology degree. Would it be silly to get a second bachelors degree in physics? Or would it be possible to get accepted to a graduate program with rigorous self-study?

1 Comment

2023/12/06

17:54 UTC

17:54 UTC

137

Just left my cosmology exam knowing I bombed it and everything else I already bombed. Feels shitty but I was lazy.

39 Comments

2023/12/06

16:15 UTC

16:15 UTC

13

thoughts on majoring in physics and minoring in computer science(software engineering) will it be super rough? Wanted to know how many are doing the same thing or completed this course work!

6 Comments

2023/12/06

13:43 UTC

13:43 UTC

1

2 Comments

2023/12/06

13:04 UTC

13:04 UTC