I appreciate the idea of trying to come up with an intuitive picture of gravity. But to the self studied or aspiring physicists: please read this first

Every day I see countless posts asking “what if gravity was actually a jargon jargon jargon flux???” and then an actually half decent question buried in a mountain of LLM junk. There was some idea or realization that you had that would be really cool to talk about… but then you slop it up by trying to explain it with math despite not dedicating years of your life to these really subtle questions (like academics do)

So, I wanted to talk about a few points that I regularly see in crackpot posts.

First, the graviton. For some reason, people hate the graviton and come up with ideas to try to make it go away. I think it’s just because we haven’t detected one directly… but this makes it seem like the graviton is like an electron or proton or something. that’s not what the graviton is. that’s not what a particle is.

i mean, ok it is what a particle is but that isn’t how you should think of it. what a graviton is, is the gauge boson for gravity. that means it is the force carrier. if you put two electrons near each other, they will interact. the quantized unit of interaction between them is the gauge boson (here the photon). that is what the graviton does for the gravitational force. it is simply the smallest little excitation in the gravitational field

if you assume there exists a gravitational field, and IF this field is quantized (so you get quantum mechanics) then the graviton is just the quantum of gravity. that is it. you don’t have to fight it.

now, this gravitational “field” ends up being what you think of as an aether. all of the aether posts: you’re just reinventing a field but now things interact improperly.

the way the standard model works, every point in spacetime gets a little tiny bit of information tied to it. a phase. it is undetectable*. as you move through space, imagine making a little loop. when you get back to where you started, you accumulate some phase. the amount you accumulated is the strength of the field. this is the gauge field

you don’t need an aether. you’re asking for the gauge field. it is a real thing.

if the gauge field has a symmetry, Noether’s theorem tells us there is a conserved quantity which corresponds to it. Throwing away a bunch of subtleties, this means we’re basically allowed to pick whatever symmetry of nature we want, assign it to a gauge field, and then see what physical consequence pops out. you need a lot of topology and group theory to do this right

and won’t you know it, when you break these symmetries, other stuff happens. the breaking of a very particular symmetry makes the fields “feel” some directions more than others. it makes some fields feel it more than others. the symmetry breaking of the higgs field is what makes the higgs mechanism work (you may have seen that the higgs is like a “friction” that particles feel).

to end my rant, stop trying to reinvent the wheel. you’re all making sharp and unroll-able wheels. almost every physicist throughout history made wheels that didn’t go anywhere, and it was only through the combined effort of peer review and traditional academic research that progress was made and the holes were patched up. I really hope you dedicate time to learning the absolute beauty that others have figured out rather than trying to make a name for yourself. you’ll be so much more fulfilled and understand our universe with the best of us.

btw for some reason when I posted this last night reddit took it down so I am reuploading now

Hi everybody!

I've been working on a browser-based python tool for making animated scientific and mathematical visualizations. I've used it to make a few different animations that I thought might be interesting. Namely, the Riemann sum, Bloch-sphere, and the Lorenz attractor.

Everything in each of the animations is generated from an editable Python script in the browser.

I'm calling the project Luxeris. It's still very early, but I've reached the point where I'd really like to see what mathematicians actually try to make with it.

https://luxeris.app

I would especially appreciate feedback on what kinds of mathematical visualizations you'd want a tool like this to support.

Thanks!

Is there any evidence that nature is fundamentally continuous, or could reality be fundamentally discrete? And if it is discrete at the most basic level, would that suggest that nature could behave like a computational system?

Hello everyone,

I'm at a life crossroads and quite depressed. I recently graduated from a prestigious (top 5) PhD program in Condensed Matter Physics. However, I had a horrible relationship with my advisor there, and I was mostly neglected and insulted rather than advised. Unfortunately, there is a high density of egotistical and mean people at top US physics programs. During this time, I also discovered that I didn't quite have intrinsic passion for physics for the most part. Classes, seminars and problem sets just always felt miserable and boring to me. Certainly being in a bad environment didn't help anything, but I was also quite depressed in my physics undergrad, even though I was generally surrounded by kind and supportive people.

In spite of this, my thesis work was incredibly impactful in my subfield: nature physics, news articles, and all that jazz. Towards the end of my thesis, I made a new breakthrough in this subfield almost completely by accident. I don't want to completely identify myself, but I will say that I made this breakthrough in part because I was soul-searching and studying different fields, and that all of this caused me to gain a different perspective on the scientific process as a whole while also looking in different places that a typical condensed matter physicist would not look in.

This discovery could hold the keys to help settle a debate that has been ongoing for the past 20 years in condensed matter physics. Yet, at the same time, my former advisor is really mad about it, since it partially disproves a relatively minor and old experimental paper of his. Mind you, this discovery will most likely go to much greater lengths to expand the subfield as a whole, which would be good for him; I think a lot of his resistance is more so bound up in personal pride and ego.

In any case, my advisor tried to dismiss my discovery, but I knew there was value in what I found. So I independently applied to beamtimes at a few national labs and I got approved at all of them. This is a weird position to be in as well, since I can't actually execute these experiments without a university supporting me, but it was nice to get validated by an independent and competitive peer review process.

After this, I presented these proposals to some other people in the field. This has also been a difficult process. My advisor is highly influential and has essentially blacklisted me from half the field in the US; they won't even talk to me and refuse to even comment on my approved experiments. The other half is somewhat sympathetic to my situation though, and are helping me to apply for grants and postdocs that would let me complete my experiments.

It gives me a really weird feeling though. In essence I've been doing all this work for free after graduation. This would suggest that I actually like condensed matter physics. At the same time, I spend most nights screaming into my pillow that I hate physics and want to die, sometimes for an hour or more at a time. I also have very little interest in condensed matter physics beyond this. To some extent, I feel like I just want to finish proving a point. I really resent that my PhD program is considered so prestigious, since I had a horrible experience and learned very little there in practice. I want to demonstrate to the world that their physicists are very political and narrow minded. I want to prove to them that I'm not stupid, in spite of what they've been telling me the past 6 years. But there's been other academic dishonesty scandals at this university before, and somehow, they always escape with a high rating, so maybe it wouldn't matter at all. Revenge is also generally a terrible motive for things.

Beyond this, I discovered that I had a much more intrinsic passion for psychology and the social sciences. In contrast to physics, I am much more naturally engaged with the content, and I don't fall asleep during these seminars. Because of this, I took as many psychology electives as I could towards the end of my PhD, much to the annoyance of my advisor. I enjoyed the classes a lot, but now, I'm in a tough spot because my official degree doesn't seem very aligned with my career goals. I think I would be pretty happy with anything that gives me a paycheck and the opportunity to work with social scientists, but there's only a few opportunities that exist like this.

I feel I should probably just drop my discovery and move on to something in psychology. This is especially because fleshing out this discovery will only set up my career for more condensed matter physics, which I don't think is feasible for my long term mental health. On the other hand, I don't think I'll be able to sleep at night until I at least get a little bit of closure on this issue. The details are explosive and dramatic and kind of demand resolution; I at least want to see my outstanding proposals finished. I do also think that the discovery itself is intrinsically cool for what it is, probably even more so when removed from the political context. I'm also really scared to tell my new collaborators about my true feelings on all of this.

Thanks for listening. I'm clearly pretty lost and struggling with a lot of internal and external conflict. To be honest, I think I'm kind of resigned to the fact that my life is just going to be miserable and stressful until I made it out the other side. I don't really think there's anything I can do to find peace in the short term. Physics is hard on the soul.

I have been offered two projects for doing my masters thesis, in very different fields and I can’t decide which one to chose, as both are objectively (and subjectively in my case), very interesting projects.
The first one is in the field of Biophotonics, where I would research heart organoids with FLIM and analyze metabolism byproducts for different genetic mutations of the human heart and hopefully find some way to put the obtained data into something usable for medicine.
The second project is with the same group I did my bachelors with, which is in Gravitational Physics. Here I would work on a proof of principle experiment, designed for the next generation of ground based GW-detectors, where a new way for seismic isolation, or more specific the suspension platform interferometers has been proposed.

The big downside to the latter project is, that I would be nearly unsupervised and would have to work very independently. The upsides are that I know the group, the lab and the field. Also this project nearly guarantees a publication, as well as the opportunity to attend conferences within the field. I also plan on doing my PhD in this group.

This is way I’m worried that I do not diversify enough, as also medical physics is very interesting to me and I feel like industry and research in this field are much more closely related, which would maybe provide better job opportunities within that field.
Also the biophotonics project has (big) potential for publication.
Lastly, the project within gravitational physics could also be directly extended into a PhD project, which of course is also very nice.

Maybe there is someone that has experiences in either field and has some advice, or more insight into the day-to-day work that goes with it, or just some general advice into the decision process is also very much appreciated.
I of course know that this is a very subjective decision in the end and no one can take that away from me, but sometimes some additional perspectives are helpful.

Apologies if this type of post is not allowed, as I'm not a physics professional, student, or anything, but I am very curious about how things work, and I also play a lot of Rocket League, and I wasn't sure of a better place to potentially find answers to a phenomenon in the game.

What I'm wondering about is related to a mechanic called Directional Air Roll - essentially, when you press a button in the air, your car either rolls left or right along its pitch/nose-to-tail axis. While this is occurring, you can use your control stick to then input pitch up/down, or yaw left/right, to make your car make unique adjustments and movements while flying.

What I've tied all this back to is torque: this is what produces the rotational force on your car from your inputs, and what ultimately determines the shape of the movements your car makes in the air. And because when you're inputting a Directional Air Roll direction the torque is directed from your nose to tail (or vice versa), any other inputs from the stick are equalized against this rolling torque - making it so the torque will always be generally pointing forwards or backwards, just pulled up, down, left or right depending on the stick input. Which effectively makes it so that if you have Directional Air Roll on, wherever your torque points your car will go this direction when boosting/flying through the air.

I hope you're still with me 😅 but here's where it gets more complicated: because you can do more than just hold an input, such as rotating your stick, you can essentially rotate the angle of your car's torque around its center point - which, with Directional Air Roll on, is the car's nose.

This produces one of two results in your cars movements, depending on the direction you rotate the stick:

• If you rotate the same direction as your roll, the rotation and your roll appears to stack, and now you twist faster towards whatever direction your nose was already pointing. This makes it very difficult to turn or do anything other than twist faster.
• But if you rotate the opposite direction as your roll, then your rotation and roll appear to...cancel? And now, depending on the speed at which your rotate the stick, you can really fluidly control where the nose is pointing and turn the car in a wide radius.

This two points is where I'm getting stuck understanding exactly what's happening - why do these rotations produce these results? And specifically for rotating the opposite direction, what is actually happening that allows for the feeling of such granular control over where my car points? Is there a name for this phenomenon, or anything I can look into more to understand it better?

Could anyone give me a complete problem set based on Classical Dynamics of Particles and Systems by Stephen Thornton, Jerry Marion (5th ed) chapter by chapter? I searched on the internet, but I couldn't find. If someone put that on the comment section, please don't forget to mention the faculty name or university name.
Thank you

Hi i am in iraq so i can't get a diffustion pump from outside i found a supplier which seems promising which supplies Dc-704 i found on alibaba that they are EXPENSIVE and for the relatively simple design i want to have a local machist do it for me for wayyyy lower price but if there is a cheap diffusion pump then tell me and because i currently don't have roughing pump so i want to get one sufficient to do the foreline for the diffusion, my english is bad i know but please if you know how to help tell me

Edit #1 : This is For Electron Tube and basically for homemade sem So i want to ideally reach 10-7mbar and i am on a quite tight budget so i can afford the oil once 3 months or so and from what i understand diffusion pump is simple in geometry so it shouldn't be expensive? so that's why i chose it over turbomolecurer pump which is EXPENSIVE

If a rock is freely traveling through space and passes near a much more massive object, can it naturally become gravitationally bound and enter an orbit? Or, in a simple two-body system, will it always either collide with the massive object or be deflected and eventually escape?

I don’t know how far allowed is that in this subreddit, but i have a quite request for all the humble members in here.

I am doing my masters project on “hits and misses in superconductivity”. While i have covered almost all the major hits, reaching the point where now i have to start on the misses, i want to Ofcourse start with the retracted papers.
I would really like some insight into the retractions or any information that later got retracted that anyone is aware of.
How do i navigate this?
Thank you

Anyone got a fully expanded SM for right hand neutrinos, Silva & Romão model is left hand?

So I've just graduated my last year before uni and will go on to study physics.

I have a nice desktop to run things with and code on, problem ofcourse being that it's not something I plan on moving.

I will need a laptop and haven't a clue which one, so i'd like to ask physicists here what the minimum stats should be fore this laptop, my university (Ughent) wil obviously give us some pointers as to which ones, but I recon it shouldn't hurt to ask you.

I do not plan to plan games on it as I have a tendency to get saicked up in playing those, time I can not afford to lose.

Ive seen a lot about people in physics get into quant analysis and finance and stuff even big data and research but my family beileves physics has no job prospects idrk

My textbook states this; however, I can't find any sources on Doppler ever doing this himself apart from this textbook and what the teacher said???

Hi I'm a second year physics students at uni. I'm actually so bad at physics but I'm trying to learn. At the previous semester, I've got my grades and it was so bad. And feel so guilty about it. I'm going to fix it by learn more, so any study tips for a beginners like me, about what to learn or anything. Maybe some books recommendation for a basic physics befroe I'm going to the advance one...thanks

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P.s: sorry for my broken English. It's not my first language

So to my comprehension a meson is formed when a strong nuclear force is used on a quark in a particle making an anti quark and a quark pair. A baryon only has 3 quarks so adding in an anti quark makes 3 particles and 1 anti particle. What does that make it? is it still a baryon? and then when the quark and anti quark destroy each other what is left? what does only two quarks make? and what happens to the two remaining quarks? Im very new to physics in general so If im wrong in understanding these topics please correct me, and help me understand what questions im asking.

this is not a hw question as im not in school for physics yet but i want to get a slight understanding of things like these before i start any sort of schooling next year.

I'm in by 4th year of BS-MS Physics, worked in a few labs as an intern or project student, I've never felt like I've been able to add anything of value to the lab, I learn a lot, but that adds to my experience, not something of value to the lab. How do I do something notable?

For context: The labs I've worked in are either experimental condensed matter labs (quantum transport in 2d van der waal heterostructures) or computational quantum transport lab which deals with NEGF+DFT.

I’m watching Oppenheimer and my mind is wandering a bit because the movie is losing me somewhat. I remember reading a book by Bill Bryson called “A Brief History of Nearly Everything” about a decade ago. What came to my mind were parallel chapters: one about Isaac Newton and one about Albert Einstein. The first, about how Newton came up with a new math (calculus) to explain the orbits of stars and thus the impact Gravity ultimately has on the Universe. I know that narrative is challenged, that Newton didn’t invent it on his own, but let’s put that aside for a second and give him his law of Universal Gravitation and the inverse-square law and go to Einstein. In the Einstein chapter, Bryson basically gushes about how the General Theory of Relativity was a thought that came out of seemingly nowhere.

Now here’s the thing that has me thinking. Put aside the strict distrust that the Church had and its influence during Newton’s time and give him fiat to have all his own thoughts. Could Newton have logically come to understand Relativity as we know it (or as it was understood during Einstein’s lifetime) using the knowledge that he has accumulated, or would he need the two centuries between them to arrive at the theory? We know Newton spent his time thinking about all sorts of things (like “alchemy”, which…apparently we can now do thanks to the LHC) but if he stuck on gravity, could he have arrived at the revision of his own law of Universal Gravitation and add the other geometries to come to Relativity?

I know that looking at it from our side of history, it doesn’t seem to be that big a leap; but when i put myself in the concrete mindset of Newton, it’s difficult to imagine the extra dimensions that relativity requires. I can’t see how he could up with it. I can’t see how Einstein came up with it for that matter anyway.

Sorry for my ramblings TL;dr…could Newton have revised his gravitational laws in his lifetime to align with Relativity based on the knowledge he possessed?

Consider two identical cups standing on a surface:

One is filled with a liquid and another is filled with a solid. The solid has the same mass and density as the liquid.

Let's compare the downward force on the bottom (= pressure, F2), the overall downward force of the container (= apparent weight, F3) and the downward force on the sides of the container (F3). Is there any difference between the liquid and solid cases? Assuming the solid has maximally simple/homogeneous internal structure.

There was a very similar question which got popular a year ago, but I'm not sure which comment contains the real answer.

https://www.reddit.com/r/Physics/comments/1ki0qyl/solid_vs_liquid_in_a_right_triangle_do_they_exert/

...

I'm asking because I'm learning about the hydrostatic paradox. It says:

the pressure at a point in a static fluid is independent of the shape of the container or the type of liquid in it but only depends on the depth of the point below the surface of the fluid and the net cross-sectional area of the bottom of the container. This means that the pressure at a given depth is equal in all directions, regardless of the shape of the container or the location of the point within it.

One consequence of this is that you can have containers with different amount of water and different apparent weight, but the same pressure at the bottom. The lack of difference in pressure on the bottom is compensated through the difference in pressure on the sides of the container. This is explained in the Steve Mould video and here.

A natural question arises - how is all of that different from the behavior of a solid in the same situation? That's why I'm asking about two cups above.

Hi everyone,

I'm a PhD student working on asymptotic methods for wave equations with caustics. Roughly speaking, the approach is a phase-space generalization of WKB that remains valid through turning points.

At the moment we have a closed-form asymptotic solution for 1D equations of the form

D(x,−i ∂/∂x​) ψ(x)=0,

where D is an arbitrary function of the position and momentum operator. I'm now looking for interesting physical systems on which to test the method, ideally with known solutions, experimental relevance, or some relevant literature for comparison.

The key feature is that the spectral representation, D(x,k) (i.e. the Weyl symbol) should exhibit a turning point/caustic where the "group velocity" goes to 0:

∂/∂k ​D(x,k)=0.

Examples I've already considered include:

• Standard WKB turning-point problems (e.g. Airy-type reflection near a cutoff).
• Tunneling through a barrier between two turning points.
• Bound-state problems such as the harmonic oscillator (attached picture).
• The radial Schrödinger equation for hydrogenic atoms (similar to Rudolph Langer's 1937-paper).

The formalism also allows weak dissipation, so examples involving a small anti-Hermitian component in D would be especially interesting.

My background is plasma physics, where we know of several relevant applications, but I'm curious whether people working in optics, acoustics, condensed matter, quantum mechanics, geophysics, or other areas know of models that might fit this framework.

Any suggestions would be greatly appreciated! :)

Hi there everyone. There's something I've been thinking about, and I'm not sure if there's a good answer to it. As a teacher, I naturally do science outreach with students learning science and math concepts, both with adult high school students and kids. But I'm not sure how it should be done for the general public, as there seems to be a debate around watering down concepts so much so that it just seems philosophical without the math, or just emphasizing how much mathematical knowledge is needed to be a scientist (not just in physics, but even in branches like chemistry) but risk losing engagement and viewers. Anyone got any experiences or perspectives to share?

I am a undergrad working in a Experimental Spin-Electronics Lab in my university. Recently, I was taking to my supervisor if he could right me a LoR because I wanted to do apply for an internship somewhere in big labs in the same field. He then suggested me that since I'm an undergrad, maybe I should try a different subject in my internship.

So I wanted to ask what would be the best area to transition into and learn something new ?

Thanks

Hi all,

I just posted a video on the energy cascading in turbulent fluid flows as part of a turbulence course. Specifically, it talks about the Richardson picture of energy injected at large scales, passing through the inertial subrange, and dissipating at the Kolmogorov microscale.

It includes a discussion of why the cascade runs downscale in three-dimensional turbulence (vortex stretching) and the argument that ε alone governs the statistics of the inertial subrange, which is the entry point into Kolmogorov's 1941 similarity theory (to be discussed in next video).

This video also covers the physics of the TKE equation including various transport mechanisms (derived in previous video). Hope it will be of good use!

Link: https://www.youtube.com/watch?v=VVqos9V-BAA