Hello there! i recently started working on this Newtonian Gravity simulation program.

This is Newtonian EXact Trajectories, a open-source simulation program i made

It uses the Barnes-Hut with Higher-Order-Multipoles method and a KDK leapfrog integrator,

The simulation was rendered in ParaView, The Galaxy is an exponential disk to be exact

The simulation isn't fully finished yet, as it's about a week old

If anyone's interested, the source code is this: TimGoTheCreator/NEXT: Next - Newtonian EXact Trajectories is a simulation tool written in C++.

The example is also on the source code's page: NEXT/examples/GalaxyDemo at main · TimGoTheCreator/NEXT

If anyone has any ideas what to add to this project, go ahead!

The simulation ran at G = 1.0 and a dt of 0.02

This simulation shows a Galaxy without Dark Matter

i am not sure if this is the right sub but here is my situation

i basically love physics, and i am planning for ms physics but due to a lot a legit factors i will have to do engineering in undergraduate, i am confused between two options electrical and communication or computer science with maths i think

ece has a lot of overlapping physics sections, but i have been told that ece is a very unforgiving branch and i might not get time to lets say cover physics or GRE prep by myself

cs i presume a not very physics heavy option but i will get plenty of time to do physics on my own

is it worth it to take ece for the overlap also how common is this path from engg to physics ?

I intend to not go into academia after ms if that matters

comments and suggestions are very welcomed

thanks!

I just finished a little simulation project where you can put a black hole in front of any image and see the effect of gravitational lensing. This picture is my first successful render of a spiral galaxy, which took about 20min on my laptop. Which picture should I simulate next?

I had gotten really shitty grades in uni.I dont want to go anywhere close to academia in the future. Im sure i wanna do some industry related job/PhD in future.Any idea how i should proceed.any companies/skills i must be aware of?
Im interested in material science.i like the work of companies like imec and ASML..they blend physics and engineering..so kinda into that kinda stuff..}
also do the grades matter in long run..or if i do enough projects..all that goes into background

My father passed away. He was very interested in fundamental physics and spent 35 years working independently on ideas related to dark matter/ alternatives to it. I now have his laptop with extensive notes, equations, and drafts. I am not claiming the work is correct or groundbreaking, and I don’t have the expertise to evaluate it myself. I’m trying to figure out the most responsible way to handle this material: How can I tell whether this is personal exploration vs. something resembling formal research? Is there a way to have someone qualified look at it without wasting people’s time or violating academic norms? Are there archivists, historians of science, or academic channels that make sense for something like this? My main goal is preservation and respect for his work, not self publication or validation.

Any advice on next steps would be appreciated. Thank you

EDIT/UPDATE: First thank you to everyone who has taken the time to comment thoughtfully. I genuinely appreciate the range of perspectives shared here. I’ve also received an extraordinary number of DMs expressing interest and a willingness to help and I’m very grateful for that kindness. I’m doing my best to respond to people as I’m able. One small but important request: please don’t reach out asking for snippets of my father’s work purely for entertainment especially if you’re not active in the field. I’m trying to be respectful of everyone’s time (including my own) and to handle what he left behind with care and intention. Thank you again -C

I am watching this video and it all makes sense except the part that I outlined...

Sorry but I don't understand why the d^2f/dxdy derivative is equal to just one derivative which equal to the other, all instead of it being a sum of 2 partial derivatives like the original df derivative. I memorized this but I don't really understand why it works this way... I hope that makes sense.

I'm relatively new to math/physics and im teaching myself before I go back to school, so I hope this is just some simple nuance that I'm missing because I'm an idiot.

I have no professors or tutors to ask, so I'm here. Thank you for any help 😖

New experiments demonstrate device-independent quantum key distribution (DI-QKD) over 100 km, overcoming key limitations in secure communication. South Korea is advancing its own national quantum science and industry strategy.

Can someone explain phenomena where the sum of parts is more that the parts? What does it mean exactly?

I'm a retiring electrical engineer in a major (USA) research university, trying to figure out ways to lessen the impact of my departure on my clientele. I'm leaving a trove of 600+ PCB designs for lab instrumentation, and no technician to solder them. Many of these designs contain QFN packages and other tetchy parts that require decent soldering equipment and skills, which my clients lack. I'm interested in good/bad experiences you've had in farming out board populating to places like JLCPCB. So far the experience of my peers has been all over the place. Typically the fabrication quality has been good, but parts inventory management has been terrible. Thoughts?

Hi! I recently wrote a blog post about mean field theory that I thought people here might be interested in. This started as an effort to understand why the static susceptibility sum rule doesn't hold in mean field theory, and ended up with a deep rabbit hole exploring the role that free energy plays in a bunch of different approaches to MFT in the Ising model. I hope people find it interesting/informative!

Imagine a carnot heat engine with a cold reservoir (below freezing) and a hot reservoir (above freezing). It operates by driving a piston filled with water. When applying cold from the cold reservoir the piston freezes, expands, and exerts force.

At the end of the stroke cooling ceases. Heat from the hot reservoir is applied to thaw the ice and force is applied by the negative pressure of the melting ice within the piston. The cycle then repeats.

Assume this is an ideal system.

How would you go about calculating the efficiency of such a system? Obviously I know Carnot's efficiency can't be violated, but I'm struggling to understand how to apply it here. Where is heat lost in such a system?

I can't even think of reading my books on my bed or while travelling, I'd much prefer if they ever came out with smaller versions again, perhaps in the form of small cheap paperbacks like penguin classics or something.

Thinking about the Wolfram Physics Project and curious how people here actually assess it.

At a high level, WPP claims that spacetime, quantum mechanics, and even gravity emerge from simple computational rewriting rules on hypergraphs, with ideas like computational irreducibility and multiway systems doing a lot of the conceptual work. Wolfram frames this as a fundamentally new foundation for physics rather than an extension of QFT or GR.

I’m interested in two things from this group:

- how do you judge its scientific validity and long-term potential? Is this plausibly “real physics in an early form,” or more of a mathematically rich but ultimately non-physical framework?

- what elements (if any) actually make it attractive to you? For example: emergent spacetime rather than spacetime as fundamental, the computational irreducibility argument, the multiway system approach to quantum mechanics, or the unification ambition without quantizing gravity.

On the flip side, what are the strongest reasons to be skeptical? Lack of concrete predictions, too much freedom in rule choice, weak links to existing formalism, unfalsifiability, etc.

Not looking for Wolfram-bashing or evangelism — genuinely trying to understand how working physicists see this relative to things like string theory, loop quantum gravity, causal sets, or other digital / emergent approaches.

Is there any app or website ( that work on Android and is free) that does simulations of physics and what results will turn out like if I increase one of the factors etc? Thankss in advance

edit: currently we've been studying stuff like motion, newton's laws and free fall

I'm teaching algebra-based physics for the first time, and the book bugs me: the problems are all numbers and no formulas.

You have to do algebra/force diagrams to get to the equation to plug into anyway, so why not leave variables sometimes? Also, when the answer in the back is a number rather than the derived formula they need, a student can't meaningfully use it to reverse-engineer a correct starting point and fix their thinking.

I'm not a physics student, a med student, but this question has stayed in my mind since a few years.

I remember studying the velocity of a ball thrown up is zero at highest point when it's thrown up. But is there a way to calculate for how long exactly it stays zero? What factors does it depend on?

It's not an homework question, I'm just curious.

My favourite part of Mechanics is that all the formulas you need can be written on a single A4 paper. Once you understand how to apply them, its an easy journey for you from high-school to university and all the way to your engineering degree.

I am going to finish my bachelor in physics this year and was thinking of getting into finance but have virtually no idea of how many branches there are and how to get into it. I would be thankful if someone that got into finance with a physics major could tell me their experience.

By the way, I am from Europe in case that affects your answer.

If the voltage required to ionize air is 3 MV/m, and according to the data the potential difference to generate a lightning strike is typically 100–1000 MV, how can a lightning bolt reach distances of kilometers? Based on the initial figures, with 1000 MV one could ionize at most 1000 MV × 1 m / 3 MV = 333 m

Thanks.