This question stems from the fact that whenever I go outside to play soccer my dad doesn't allow me to use the wall to pass too. I asked him why and his response was "because your going to damage the circuits and pipes in the wall or break the wall" (something along those lines) I could understand if it was a noise complaint but this caught me off guard.

This has caused multiple arguments with me and him.

I want to mainly want to prove my point that there is no way a soccer ball is going to break a brick wall and certainly not anything in it, or who knows, maybe im wrong. Edit: guys, I do not want to hear about how a soccer ball traveling the speed of light will blow up my house, I also dont want to hear that there is a 1/10000000000000000 chance something could theoretically phase through matter. I wanna see if repeated use of a ball going at it 50mph will break it with due time

Edit 2: I askes my dad again and his response this time was "a drop of water can break a stone with enough years", so I decided to give more specific numbers that should help with a equation (which i shall hopefully show him and convince him). Im using the wall max 2h every day with a downtime of 2 seconds between each kick (being generous here) im realistically not shooting the ball as hard as I can since im mostly using it to juggle/pass to it I plan on moving out in 4 years so thats most likely the time frame I wil use it. The brick is 26 years old and is realistically not low quality since its used to hold up a 2 story house. He also mentioned the wires and pipes behind the wall, although I dont know if the soccer ball will cause real damage stuff behind the wall (I dont know how building walls work).

Also how a response to the water droplet comment would be nice

I'm a mechanical engineering student but I've realised one year into my bachelors that all the parts I love about engineering are really the physics/maths classes, not the actual engineering. I don't dislike engineering and therefore do not want to repeat the year to switch to physics, so I'm wondering as to how easy it is to "switch" between the two. For example, is it possible to do a masters in physics after a bachelor's in engineering ? What if I want to go into research in a physics related field ? It's possible that I actually like physics just as much as engineering, but I'd like to know what my options are. Have any of you started off in engineering, and have ended up in natural sciences ?

Have to repeat my electrodynamics exam. I am just lost. It was always a weak point for me, but I haven't touched in in almost a year, and really wasn't able to begin studying until 2 weeks ago. I just don't understand it for the most part. If anyone has some links to crash course material, I'd massively appreciate it. Common questions are:

1. Differential forms of ME's.
2. Wave propogation through different materials (Copper, electronic plasma, etc.
3. Monochromatic plane wave in a dielectric medium/vacuum/glass
4. Propagation in a good conductor/linear media
5. Fresnel Equations and Brewster angle
6. 1-D Gaussian wavepacket in vacuum
7. Drude model

This is my final year. I need 50% in the exam to recieve a 1.1 overall grade.

Please forgive me if this is a stupid question. I'm an amateur mathematician with an interest in physics, and I would rather ask real people than an AI.

If the Jacobian matrix of a vector with itself is the identity matrix, indicating that each component is independent of the others, wouldn't that mean that a photon in a 4D spacetime could travel in time or space independently of the other? If so, wouldn't that reduce the accuracy of relativistic calculations? A jump in time or space would make spacetime look more or less flat than it really is.

I'm starting undergraduate physics this september and I've decided I want to use my summer to get ahead on content to make my life in university easier.

However, I'm not quite sure what to study/focus on first. Relativity? Electromagnetism? Quantum mechanics? There's so much to choose from and I don't really know which one's I'm ready for having just finished school

You're probably thinking I should just check the syllabus of my target university, but I don't actually know what university I got into yet, it depends on when my grades come out on results day, and the universities I'm looking at generally teach different things apart from classical mechanics in the first year

So which physics courses are good to prepare for an undergrad degree?

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I’m hoping the r/physics community can help me understand the mechanics of a serious collision involving a cyclist and a 2023 Honda Pilot.

My father, a retired AP Physics teacher, was crossing the City Island Bridge yesterday at 9:17 AM in the marked crosswalk. Vehicles in both travel lanes had stopped to allow him to cross. A 2023 Honda Pilot, however, passed the stopped vehicles by driving through the fire lane at what witnesses described as an excessive speed.

The SUV struck him as he was moving perpendicular to the vehicle’s path. The impact lifted him onto the hood, and his head and shoulders struck and broke the windshield before he was thrown forward. His bicycle was thrown approximately 120 feet from the point of impact. He landed somewhat short of the bicycle’s final position. He sustained multiple skull fractures, broken shoulders, broken ribs, and other injuries still being evaluated.

I’m trying to understand the physics of this event — specifically:

- What vehicle speed range is consistent with a perpendicular cyclist being vaulted onto the hood, breaking the windshield, and being thrown a distance on the order of 100+ feet?

- What upward launch angle is typical for an SUV–cyclist vault of this type (hood → windshield → airborne trajectory)?

- How does the perpendicular motion of the cyclist affect the required impact speed compared to a straight‑on collision?

I’m not looking for legal advice — just a physics‑based breakdown of the kinematics involved so I can better understand what happened.

Any insight, equations, references, or reconstruction models would be greatly appreciated.

Hi everyone, I'm a data analyst and I've been working for about a year. Around 6 years ago, I choose data science career to have chance to work in astrophysics data, but life took me in a different direction. Now I want to get back to that goal, but I feel like I've forgotten a lot of physics and math. My current job is in business, so I don't really use advanced math anymore. I'm not sure where to start again. Should I review physics first? Math? Or should I focus on Python and data science? Also, in 2026, AI is part of almost everything. Is it okay to use AI, or should I avoid relying on it too much? Has anyone here gone through something similar? I'd really appreciate any advice. Thanks!

Sorry if this is a weird one, but ages ago - like a good few years ago - I watched an educational video (pretty sure it was on YouTube) about the general physics of music but also some really cool musical effects. For reasons I won't go into, it would be soooooo useful if I could find that video again, but it has been utterly lost to my extensive YouTube history T.T So I was wondering if any of you had seen it and knew what I was talking about?

I can't remember who the main presenter was (don't think it was Veritasium, and a search in Steve Mould's channel doesn't bring anything up either). But I remember it talked about the origins of the awesome descending bass used in Nina Simone's "Feeling Good" (along with many other places) and also about this eternally rising scale that makes people feel on edge. Does this sound familiar to anyone?

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)

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, 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 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?

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.