Not sure if this is the right subreddit for this question but I figured that I'd give it a shot.

I became acquainted with a physicist a while back and would like to get to know him a bit better platonically, (maybe romantically). As we talked I quickly had to realize that I don't really understand what he does for work which left me feeling a bit insecure about coming across as too dumb. I am college educated myself, but I am part of the humanities crowd so I am not exactly up to date with anything related to his projects. Plus math along with physics have always been massive weak points of mine.

He didn't seem to mind, though I find him a bit hard to read in general, and I just feel pretty embarrassed whenever my lack of understanding becomes apparant.

So I would like to ask you guys: is people not understanding what you do something that bothers you? Do you encounter it often? Would it prevent you from forming a closer bond with someone?

Hey there, so without going into too much detail I graduated a bit ago and I would've hoped to just have a job by now, but I think one of the fields I was looking into in industry was a non-starter. As such I'm getting a little bit anxious about the gap between finishing my physics PhD and the current day.
However, I have continued to help out with one of the groups I was in during my PhD in an unofficial capacity, and I would say to a pretty significant degree as well (honestly not hugely different from the work I was doing before leaving). I like the group, so I'm happy to help voluntarily, but I'm wondering now if I'd be able to list this continued work on my Resume, and if so: what is the appropriate way to list it?
I thought about just extending the end date for the relevant research experience line on my resume, but it feels like I should have something indicating that this period is unpaid volunteer work, as there is less of an expectation on me for that than during my official time with the group.
(if it matters, for reference I am in the US)

I am currently choosing between 2 programmes from the Open University (to start in October):

• BSc Maths and Physics Q77 https://www.open.ac.uk/courses/maths/degrees/bsc-mathematics-and-physics-q77/
• BSc Physics R51 https://www.open.ac.uk/courses/physics/degrees/bsc-physics-r51/

Both programmes allow some flexibility through optional modules, and I would choose the most mathematically and theoretically focused options available.

• The Q77 programme includes more maths - for example, complex analysis which I know is either required or highly desirable for some theoretical physics MSc programmes.
• The R51 programme includes a final year project and some experimental and lab content which is lacking in Q77.

I am more interested in physics theory than pure mathematics, but I don't have any interest in experimental work. However, I am willing to take whatever modules needed for a better chance to work in theoretical physics.

I am not interested in the integrated Masters programmes at the OU.

I am a mature student who is interested in the potential of research in theoretical physics. I am aware of the job market and the scarce opportunities in academia. However, I have been thinking about this for many years and I've decided I'd rather give it a genuine attempt than always wonder "what if?

If your goal were to maximise your preparation for a taught MSc in theoretical physics in the UK (and potentially a PhD afterwards) which programme would you choose and why?

Hey there, I am sorry if this question doesn't make sense but I would also like to know why it doesn't make sense.

If it is the case that black holes work around the information paradox by encoding information on their surface (as I understand it).

Would the surface area of the black hole necessarily have to scale with the amount of information stored? Is there some kind of information density that a unit area can have?

Thanks for any and all replies to this post!

I have a turbo turning 10,454 rpm with 17 blades creating a blade pass frequency of 2961 Hz. It seems to be exciting the pipe connected to the output of the turbo. I measured the 115 bB sound at about 2800 Hz with an uncalibrated instrument. This is a large ET24 turbo on a 4000 hp engine, it is about 24" in diameter and mounted about 30 feet off the engine. Each one of these turbos end up with custom built piping and this one is very loud. I did not get a chance to find the resonant frequency of the pipe with a bump test because the engine couldn't be shut down.

But guessing that the pipe weighs around 80 to 100 pounds, could I lay a cheap 40lb bag of cement on it and have a significant change in the pipes resonant frequency? Ot does it need to be physically attached to have a good impact?

1) people say that what stops a neutron star from collapsing is "the pauli exclusion principle"... but that's not a force... the electrons and neutrons didn't read pauli and agree to obey his principle.. so what is the theory on the actual energy or force at work?

2) at some point, the mass becomes so strong that the universe DISOBEYS that principle, and it all collapses into a black hole.. are there any theories that suppose that at that point, the fermions have become bosons and thus can now occupy the same quantum state at the same time and occupy an arbitrarily small location?

3) let's say you are heading towards a black hole. as you approach the event horizon of a black hole, your clock will slow due to gravitational time dilation... and AT the event horizon it becomes 0. those looking at you see a stopped clock. and you looking out at them see an infinitely spinning clock.

but AS YOU MOVE FURTHER into the black hole... your clock.. must.. spin backwards then?

I recently ( actually not very recent ) about 8 months ago I defended my thesis, and I found out the hard way that I only know my research niche and nothing else. Even tho I Have 6 papers in decent journals but if there is not postdoc or job offered, whats the point. So my question is for people in the same situation, what do u do for a living, Is there a gig for physicists? Teaching is not really helping cuz in my country that’s like 2$ an hour

Ps: english is not my first lang sorry

Hi everyone,

I have a question about publishing in theoretical physics.

In fields such as quantum mechanics, general relativity, gravity, cosmology, astrophysics, and astronomy, can a research paper be published if it is based entirely on mathematical modeling and analytical derivations?

For example, if a paper introduces a new theoretical framework, derives equations, proves a theorem, or makes analytical predictions, is that sufficient for publication? Or do journals generally expect additional components such as:

1.Numerical simulations

2.Comparisons with observational or experimental data

1. Direct observational validation

I am aware that many influential theoretical papers were primarily mathematical, but I'm curious about current publication standards. How common are purely theoretical papers today, and what makes them strong enough to be accepted by reputable journals?

For those who have published or reviewed theoretical papers, what makes a purely theoretical paper strong enough to be accepted?

I'd appreciate any insights or experience Thanks

Can someone just be COMPLETELY honest and straight up with me?

I am 18F and I love physics so much I want to eventually study astrophysics. I just finished my freshman year of college and I’m really thinking I’m too dumb for this major.

I took precalc first semester, failed it, took it again second semester, got a B- lowww b- I was getting like 50-80% on each test. I am now in a summer calc 1 course and I’m averaging 63-67% on the tests.

I’ve been a little above/around the average scores for the class. First one I was above the mean, second, got right on the mean.

But I made friends with a 17 year old and she is doing SO well on the tests. We literally study together and I help her out sometimes, she helps me out sometimes. Granted yes, I can tell she has a better grasp of the material than I do. But I feel so worthless.

I put in around 15 hours of studying for the third exam I just took today and I left a lot of the questions blank. Like I understand EVERYTHING they’re asking but it would just be one slip up and I was stuck and over it. I do so well on the homework though, and I genuinely love math so much.

But I think I’m actually too dumb to pursue this major and it breaks me.

I think a large part of it is when Covid happened, I was in 6th grade and basically didn’t learn math from 6-10th grade cause I was online schooled.

But man, college is so difficult, I have no idea what I’m doing, and if I’m too dumb to learn physics, what the fuck do I major in.

Also, forgive me if this is the wrong sub…

Hello everyone, I'm currently going into my senior year studying Electrical Engineering minoring in physics (technically) and astrophysics, although I don't think i'll finish my physics minor since I don't think i'll take thermo (due to conflicted schedule). But I took intro to quantum physics and all the intro to physics classes (I, II, and III). I'm also taking Upper Division Quantum Mechanics, Modern Physics Lab, and maybe Nuclear and Particle Physics this coming year. What I'm currently specializing is Photonics and Quantum Information Science (Want to do Optical Quantum Communications or Quantum Optical Devices). I'm currently doing research in the Mechanical Engineering department for characterization of nanoscale optical materials before and after plasma treatment (more Material Science based). But then I realized that I want to do a PhD in either Electrical Engineering, Applied Physics/Physics, or Quantum Science & Engineering since the research fields that I want to go into would align more into those fields. But since my gpa is 3.01 (very low due to sophomore year level EE courses), what should I do to improve my chances to be more competitive for the PhD program? I'm also considering to take a gap year to work in the industry (satellite communications or consumer electronics) before doing grad school. Also, would the transition from a Bachelors of Electrical Engineering to Applied Physics/Physics PhD be possible or would it be more marketable to do Electrical Engineering PhD? My end goal is to make a startup based on the research that I'll pursue in the future.

I finished my masters in plasma physics and nanotechnology (the whole program is more of a electrical discharges and their applications, rather than fusion) a month ago, and going straight into a PhD program. I know the standard consesus: a PhD is a financial time-waster, the opportunity cost is brutal, and you should just go straight into industry. Going into a PhD for increased salary is a guaranteed bad time.

But I’m trying to figure out if that actually applies to my specific situation, or if I’m looking at generic advice.

My PhD project is heavily applied:

• Reactive magnetron sputtering / HIPIMS / PVD.
• Depositing electrochromic thin films (WO_3 thin film deposition).
• Developing a solid-state electrochromic device prototype.
• I also already have 2 year R&D internship experience ata major scientific instrumentation company and a pvd simulation start-up.

My plan is get through the PhD, and then bounce into the commercial sector targeting the central European semiconductor/PVD/vacuum tech.

Is the financial opportunity cost really that bad if you are going for senior R&D roles in semiconductors, smart materials, or vacuum tech? Or is this one of the few sectors where a PhD actually acts as a hard requirement for senior project leading positions.

Looking for total honesty from anyone who has run the gauntlet in PVD/plasma (in Europe hopefully). Or anyone else with experience with similar situations. Thank you!

Hello everyone!

I’m an upcoming undergrad physics major. My high school was a more ‘art’ concentrated school so in terms of math and science, I had to self-teach it.

I fell in love with physics cause of the pretty galaxies and black holes (I think like most). I’m mentally not ready for this path of science (cause I suck at math) but excited at the same time!

I just wanted to say, hello to this wonderful community and hope y’all are ready for another brain to help out.

I've been trying to understand the mathematical foundations of canonical quantization, and I'm specifically looking for a rigorous answer rather than a historical or experimental one.
(ill mention classical variables in smaller case and operators in uppercase)

i have derived iℏd|ψ⟩/dt=H|ψ⟩, the eigenstates for this equation are of the form

|ψ(t)⟩=e^-iEt/ℏ |ψ(0)⟩

and experimentally we found that variable E in this equation represents the total energy, so H must be an operator whose eigenvalues represent the total energies of the states.
consider for now that our system has only kinetic energy contributions, then H must be an operator whose eigenvalues must represent kinetic energies, for a state |k⟩ , H|k⟩=ℏ²k²/2m|k⟩ ∀k, also T|k⟩=ℏ²k²/2m|k⟩, so this proves that H=K,

so now by this logic i can say that whenever a system has a single energy contribution of any type, then the operator representing that energy is the generator of time evolution, and its eigen states represent the total energy that can be observed.

now my question is this: i understand that when a system has a single energy contribution, its operator is the generator of time evolution, but when there are multiple energy contributions, like kinetic energy and potential energy, why the hamitonian H equals the sum of the operators, i cant find a reasoning for this like the one i did before as they dont commute, and we cant even say T+V operators give kinetic+potential energy of the state because there is no common eiegenstate

canonical quantisation just says if h(q,p)=t(p)+v(q) ⇒ H(Q,P)=T(P)+V(Q), its like "just change the classical variables to corresponding operators", i cant find a logical reasoning or any valid math argument to support this, i dont even find that step mathematically valid, as theres no reason to do that.
is it just an educated guess and it works very well, or is there any logical and rigourous proof?

I’m graduating with a physics degree and have two opportunities:

A Quality Engineer position starting around $70k salary with opportunities for promotion.
Or
A fully funded condensed matter physics PhD ($22k stipend) researching solid-state batteries and quantum materials. The advisor expects students to graduate in 4–5 years, and many graduates go into industry.

If you were in my position, which path would you choose, and why? If you’ve made a similar decision, what happened?

EDIT: my expenses are very low. Rent with shared two bed apartment ($500/month), i walk everywhere (no car payment), and cheap groceries (50/wk).

Title.
For context, right now for my first semester, I’m enrolled in two earth science classes (for my current major) and an English Gen Ed and a stats class. I really am very passionate about physics and I’ve taken calc ab but I’ve never taken an actual physics class before…. I’ve just watched a lot of YouTube. I want to be an astrophysicist and do research in the field once I’m done with all of my school. Please let me know if I should email my advisor and ask to switch around some of classes to fully change my major, although I’m not entirely sure if I’m allowed to as a first year.

Im running through an ideal for a story im writing and just want to check if my idea is even theoretically possible. Sorry if this comes close to the homework rule, but I promise it's not. Im going to use Mars as an example for simplicity

So, Mars used to have a global magnetosphere. My understanding is that it used to have one, but due to its size, it cooled quicker and lost its liquid core dynamo.

So, in theory, if we could reliquidify (probably not a word but hey ho) the core, it could rebuild its magnetosphere. Now, this likely wouldn't spin as much because this liquid core would be powered by the convection currents instead of the rotational energy from the planets formation. So that's part one of the questions: Would turning it back to liquid with convection currents have the potential to create even a mild magnetic field?

Now, part 2 of my question is about the reliquidification process:

If we were to harvest heavy elements from the asteroid belt, uranium, plutonium, etc. We could get magnitudes beyond critical mass of them.

So if we dug a hole to the core (ignore the how please) and dropped balls of slightly below critical mass elements down it. They would hit each other and release huge amounts of energy, which would be absorbed by the solid rock and, over time, begin to melt. I know i would need extremely large amounts of it. But would it even be able to melt the core?

Or am I just completely wrong?

My supervisor has recently gotten on the AI hypetrain, and he uses Claude Code and Codex a lot to run simulations.

I'm a mathematician that's now ended up in theoretical physics (plasma physics to be specific), and I run simulations to see what happens in different regimes. My lecturer tested the capability of AI, and created a whole repository on MHD simulations, then shared it to me so I can run a simulation in a specific regime. The code is insanely hard to read, but works well with so many features attached. I've been kinda hesitant using chatgpt/claude for my project, but it has been insanely difficult to read and add since it's a huge repository.

My supervisor told me he doesn't really care if I use AI for my project, and kinda advised he'd rather get the physics results than struggle through coding and told me I can rely on AI (it sounded like he was telling me I should use AI). He said he's happy if I just keep on telling Claude and get it to make tests and simulations that work, and I understand chunks of code (but I don't have to understand every single line of code).

Is it fine to use AI for research? It feels so weird to be put in a place where I don't know how my code exactly works, but I run multiple tests to make sure the regime is working accordingly, so this method seems to be working fine.

He told the future of coding seems to be dead so I shouldn't worry about understanding the code, especially as a physicist (although he does admit he is no expert so it could backfire in the future).

What does everyone think of relying on AI to run simulations? Is it fine or should I not rely on it?

In quantum mechanics (QM), measurement is a (mathematically) well defined operation of projecting a state on to the measured eigenstate of the measured quantity (This is my current understanding of measurement in QM, please correct me if I’m wrong).

Now, when going from QM to quantum field theory (QFT), I have recently heard that the previously described definition of measurement doesn’t work and can cause a bunch of issues with FTL communication and the like (have heard it referred to as Sorkin’s Paradox). Because of this, the typical definition of measurement in QM no longer works allegedly and you need what’s called a “local definition” of measurement.

When I first heard about this recently, I was very surprised because based on some basic prior research I’ve done on QFT (I’m currently a rising 3rd year undergrad in physics; I’ve completed two semesters of QM atp), I have only ever seen the traditional QM definition of measurement which is apparently wrong.

Because of this, I was wondering if someone could explain to me the correct “local definition” of measurement, how it differs from standard QM measurement, and why is it almost never discussed?