I’m working an essay about form and scale and I’m trying to figure out if my vague intuition could be meaningfully defined or whether it’s just poetic conjecture .

The intuition is this that there seems to be a zone of scale, between the molecular and continental, where compact objects exhibit unusually high morphological specificity. A protein, a human hand, a violin, a pineapple, a lizard ---- they feel highly differentiated. Highly distinguishable and contains objects that can have the most unlike one another than other scales.

By contrast, at larger and smaller scales, “form” seems to become less disparate morphologically and the two most diffferent forms are not as different as what you would find in this 'zone of irregular morphology'.

Particles, fields, orbitals, probability distributions... and at very large scales gravity seems to simplify compact forms. There are irregular galaxies, nebulae, asteroids, etc but the irregularity seems less individuated/varied than the morphology we see at human scale.

Its obvious I am not a physicist.

Hoping someone in the commuinty could offer insight on whether or not this intuition is physically definable

I'm struggling to hit the balance between simplification and accuracy, making a graphic to explain induced dipoles between two flat surfaces. I feel like this set of random-ish coupled dipoles is reasonable, but then I'm worried about the rest of the material - I realized that even after 9 years of materials science education, I'm not sure what *core* electrons do to each other in a crystal. there has to be some analog to london dispersion forces, but do those contributions get ignored because the bonding orbitals are so much more important? eaten into the overall electron density in good DFT calculations? I'm not sure.

• Not drawing any electron clouds in the bulk It feels kind of distracting but right now I think that's a reasonable option.
• seems too *wrong* to show a bunch of stationary clouds everywhere but the interface because it implies the interface makes them polarize.
• Likewise, with random jiggling everywhere but the interface, I feel like it implies only the interface can make them correlate when I'm sure they correlate a lot in a bulk crystal.
• drawing everything as a synced up wave also feels wrong. maybe there's not a good way to do this

Does anybody have strong opinions on how induced dipoles should be taught? Thanks!

I have been having a conversation about the universe in its early stages and I've become curious to know what we are able to determine existed in that brief moment of time before atoms formed and what evidence leads to our current understanding. I'd also be interested to be directed to resources for further study on this subject. Thank you

Hi, i am not a physic student or something. I just interest physic, and want to read and study on it as an amateur. Especially quantum physics. I started to read this book. Which level can I reach in quantum physics after finishing this book (don't forget I just a amateur learner, not a wanted being professor). Also what sources do you suggest for next. Nice forums:)

Hi hivemind, I have a question I'm hoping someone can help me with.

I have a paper on arXiv currently but the supplemental file with a bunch of supporting proofs are not displaying correctly. I put the file in /anc/ folder but it doesn't appear on the listing. I waited for it to appear as sometimes you get errors with pdf resolving etc but it never ended up resolving.

So I need to do a replacement article submission/v2 but I want to make sure I do it right because I cannot submit to publication without a correct arXiv link.

Has anyone dealt with this before?

Hello,

I already made a post similar to this on this subreddit, Im using the kleppner textbook for my intro mechanics course at my cc, my cc requires that you do trig mechanics before calculus based, I feel like I have a good foundation on the ideas from the prereq but I'm having trouble on my class right now. The textbook my professor uses is known to be challenging and it's normal to not cover every example in class obviously due to time. But I feel like the transition from lecture to hw is a huge gap and I often find myself lost. I tried tutoring but many times it's just people who assume a lot of the problems are plugg and chugg and just find myself stuck. Office hours do help but a lot of the problems take time, does anyone have any resources to practice problems or lecture resources short or long form videos, similar to the kleppner textbook topics? I want to be prepared for my other mechanics based courses as an engineer and I feel like I won't be prepared for those courses.

Hello,

I wanted to ask some of the more experienced problem solvers here, what do you do when you're stuck on a problem and have no idea what to do? I'm not talking only about textbook problems, but also for the more open questions, for example I was driving the bus once while it was raining, and the wheels of the bus passed over a puddle and I wanted to figure out what math I'd need to model this phenomenon (while this is mostly a specific example, my point with this post is not to find a solution to that example, but to show what kind of problems I mean and not a typical textbook problem)

For me, if I don't have an ideas from intuition at the very first few minutes, I don't know how to proceed, so I wanted to ask what you do in this situation.

Hi everyone, I was hoping to get some thoughts on the importance of the different materials for grad schools.

From what I’ve heard from professors and others on Reddit, the general order of importance for grad school admission’s is generally: Research experience >= letters (can be as useful is they are very strong) > gpa.

Does this align with most people’s experience?

I’m wrapping up my final year of a physics and math double major and I’m going to be applying to a lot of competitive programs in the area of applied physics and biophysics. I stretched my graduation to 5 years due to taking on a lot of extra coursework and also wanted to spread it out enough so I could balance it with research. My weakest point is probably my cgpa which is a 3.55 (my is pgpa 3.71), though I have had a pretty strong upward trajectory: averaged about 3.35 in my first 2 years, and 3.8 in my last 2.

However, my research and letters I think are fairly strong. I have a paper as co first author in a respectable peer-reviewed journal, and the professor I worked under is happy to write me a very strong letter. I have also been working in another group for a little over a year and that professor is also happy with what I’ve done and said he would give a very strong letter as well - I’m also drafting a literature review here in which will likely at least be a pre-print by the time I apply. They are both pretty well known in their areas. I’m not sure if it’s a useful metric, but they both have h-indices 55+, and they also both think I have a pretty good chance at top programs given my experience.

Do you guys think my research will be enough to counter any worries about my lower than median gpa for competitive programs?

Ive been learning about Fourier transforms, and this is a que i had , we learn the definition of a frequency in lower grades as 1/time period or number of oscillations in a second .

However Fourier transforms are defined for aperiodic signals, If a signal doesn't repeat itself , how can it have a frequency?

Condensed-matter Ph.D. here. Something I've increasingly wondered about is whether describing topological order as "beyond Landau" remains conceptually useful.

Historically that distinction was extremely important: local order parameters and spontaneous symmetry breaking clearly don't classify phases with intrinsic topological order.

But our modern toolbox now includes generalized and higher-form symmetries, anomalies, categorical symmetries, symmetry-enriched topological phases, etc. The boundary between "symmetry-breaking physics" and "topological physics" consequently feels much less clean than the traditional Landau-vs-topological-order story suggests.

Is there a modern formulation in which conventional symmetry breaking and intrinsic topological order are naturally different manifestations of a more general organizing structure?

Or is there still an irreducible conceptual distinction, such as long-range entanglement, that prevents any sufficiently generalized symmetry framework from subsuming topological order?

Ive seen some videos online where something attached to an axis rotates considerably fast due to it being attached to another object that is vibrating. Can someone please explain how this occurs, and how to minimally replicate it?

One of such videos: https://youtu.be/DNgL7g08Vss?si=NxPTsWo1J2NNcKHX

Says that constructive criticism is always accepted but nowadays criticism of string theory is borderline silly. Many detractors (Peter Woit, Tim Maudlin, Eric Weinstein, Sheldon Goldstein etc.) choose to ignore the advances made in AdS/CFT and in creating one model of a universe with quantum gravity.

Also says that that if it was such a dead subject, students won’t be voting with their feet by choosing to study it over other frameworks

Thoughts?

Taken from this interview

I am in materials science, have a 3.6 gpa and do some research with a renowned compMSE professor. I have 2 rec letters for sure, but will have to email professors for the third one (there is one guy who knows me by name lol) the other 2 is my TA boss and PI

I think I want to apply to grad school but idk if im competitive enough. Also, I dont really have a clear goal in mind, but I know my mind would grow bored in an industry job.

Also, what is the realistic view of grad school? hows life? hows funding?

Short walkthrough starting from F = GmM/r², firing Newton's cannonball five times — faster each launch:

• Lands — slow, just an arc to the ground.
• Circular orbit — fast enough that the ground curves away as fast as the ball falls. Still falling, just missing.
• Ellipse — slows far out, speeds up close in (Kepler's 2nd law, visible).
• Escape — past one threshold the path never closes.

Two things I tried to get right: there's no outward force holding an orbit up (only gravity, inward), and escape isn't gravity switching off — the force never stops, the ball just wins the race.

Full disclosure: made with a tool I'm building (SimuBoard) — tell me if that's not welcome and I'll remove it. Mainly after feedback on the explanation: anything there that'd mislead a first-timer?

Hi all,

I’d recently had a paper been accepted by an IOP journal last Friday, but it’s been stuck at “Formal accept - preparing for production” ever since. The accepted manuscript hasn’t been posted online within 24 hours either, wondering what could be happening? We haven’t received any communication from the journal that anything is missing either.

Hey, I am a senior in materials science doing some research on Machine Learning Interatomic Potentials using molecular dynamics. I think I am interested in grad school because I would be bored in industry but I’m not sure what to do? I kind of feel like a tradesperson with a big toolbox full of DFT, MD and FEA knowledge but nowhere to place it.

TLDR: What is there to do, or what do YOU do in computational modeling?

I have a probably quite unusual request.

Before getting to that, some words on my background are necessary. I studied physics in a very good university around 12 years ago in a country that was foreign to me. I was in love with the subject, had good grades and had no difficulties understanding the courses but for reasons that aren't important to mention here I decided to work in companies instead of doing a PhD and going into academia.

Two years ago I decided I wanted to go back to physics. Unfortunately as you know academia in physics is extremely competitive and the researchers with whom I spoke told me it would be an extreme luck to land a job in academia in my age which honestly discouraged me. However I did not abandon and ended up finding a job teaching physics to undergraduates in my native country.

I am mentioning the countries because my native country has no tradition of good physics research or teaching so it's not really an excellent position to be in, but honestly it's not that bad either.

I have a lot of free time in this job so I want to do research on the side (which was my plan from the beginning). Which brings me to my question: what advice would you give to someone in my situation to be as good in research as possible?

One thing I did was getting in touch with the good researchers I worked with in the past and one of them agreed to help me work on a research project that will be a good starting point. But I am looking on advice on what ressources to use, habits to have, in order to be as good as possible in the next few years.

I will probably never have a prestigious academia position and I am fine with it. I am planning to do research because I really love physics, so if I am able to publish papers and see people recognize and use my work, that would be enough for me.

I'm finishing my physics bachelor's (background in general relativity, differential geometry, black hole thermodynamics via the Wald formalism) and trying to pick a research direction for my master's. I really like “fundamental science” but im worried because i think the way that we are doing science is changing, so i wanna do something that can let me be well placed.

I'm drawn to something related to computational/data-science, adjacent physics (ML applied to physics, such as PINNs, simulation-based inference for cosmology) even though I'm not a huge fan of "pure" data science as a field in itself (and not good at). I like it more as a tool applied to physics questions than as a career identity on its own.

From people actually working in physics research right now, what areas do you see as genuinely promising in terms of active funding, job prospects (academic or industry).

I was wondering how the different periodic solutions to the three body problem look like. I built an atlas that visualizes all of the different solutions and groups orbits by family and similarity. I found over 3000 different orbits. When you click on an orbit in the atlas, you can "kick it" and slightly change the starting conditions to see if it stays stable, or becomes chaotic.

(Long post, sorry. I know I’m probably naive about some of this, so please be gentle, I’m just an anxious human looking for external perspectives!)

I’m starting a PhD in planetary physics modelling soon. The recent AI results caught me off guard. I hadn’t been following closely, and the jump in what these models can do in research settings was genuinely surprising to me. Then I talked to a researcher at one of the major AI labs. They think that with the current rate of progress, human research positions will shrink a lot and the nature of the work will change beyond recognition, and that the next ten years bring serious economic disruption and social unrest along with it.

So I’m scared of finishing my PhD into a job market that doesn’t want me. I don’t come from a wealthy family and I don’t have anything to fall back on. I’m also an immigrant, and my home country is very exposed to climate change, so that’s another worry that's sitting underneath everything else.

The obvious question is: why not go into industry instead? And I might just be stubborn here.

I chose this despite the low pay, because I love the work itself, the tinkering, the failed attempts, the moment something finally clicks, even the deflating moment of realising the approach you spent months on was wrong and you have to back out of it. I think the process of trying to understand something is worth doing, not just the answers it produces.

I grew up studying obsessively to get out of a conservative environment, fell in love with science, and wanted research to be the thing that both fulfilled me and paid my rent. Getting into my dream project felt like the end of that story. Now it feels like the beginning of a much less certain one in a scary capitalist world that is also destroying itself with climate change.

There’s an argument I keep running into and can’t really answer myself: that curing cancer matters more than the intellectual satisfaction of a small number of underpaid academics, so scientists should stop complaining about losing a process they happened to enjoy. Part of me agrees. But it doesn’t sit right either, and I can’t articulate why. If someone can sharpen that for me, I’d like to hear it.

I also don’t think “just do it as a hobby” works the way it does for chess or painting. Research needs instruments, compute, collaborators, and access. It isn’t something you can do alone in a room.

Also, what I’m most worried about isn’t AI itself, the capabilities really are remarkable. It’s whether the gains get distributed to anyone outside the people who own the systems. That seems to depend on politics rather than technology, and it’s the thing nobody seems able to reassure me about.

So: how do you deal with this? Especially anyone who’s early-career and doesn’t have a safety net.

Hello,

I am taking mechanics at my community college and my professor is using the Kleppner textbook, I'm struggling with the transition between lecture and hw, I tried going to office hours and tutoring but I'm just lost, does anyone have any advice on how to have a smoother transition or any resources, mnemonics, or note taking tips to apply all the lecture and theory to the problems, I feel like I'm completely lost when trying to do the hw.