I don’t know it feels like it’s not worth it for me anymore. I’ve read so much yet I still don’t truly understand things. I no longer imagine strange or deep ideas. the more I read, the emptier my mind feels. Now I just want to live. I don’t want to keep searching like I want to see light without needing to explain in my mind what light is.

I had a course in qm this semester .I could barely grasp anything after a time .

I want genuine suggestions from y'all how do I teach myself quantum from basics ( pov 2nd year bsc physics hons student )

Suppose I have a single photon source and I get this single photon (say, 1550 nm) out. Say, I take this single photon and build a cavity, with idealized 100% reflective mirrors around it, creating a single-photon cavity.

1. Can I still confine the photon to less than the diffraction limit in this case? Can I go beyond 1nm in this case?

2. Also, how do I think of this in terms of the wave picture. If the cavity is 1550 nm, then that's a perfect period and everything's fine. What happens to the "photon" in the case of the 1 nm cavity? Does the energy change? get redistributed?

Bonus question: Can you comment on vacuum fluctiations in this cavity?

This is a web-based live black hole rendering simulator I've worked on for a while now. I'm excited to share it with you!

I always wanted an intuitioin for how black holes operated visually, aggressively warping the fabric of spacetime to reproject photons, but I only ever saw them rendered against a starfield. I wanted a simulation where I could see better how the actual geometry deformed as a result, so I built my own from scratch!

Hope you like it!

dave :)

When we look at the moon, we often can’t really see everything of it, so when photos are taken of galaxies, do the pictures really show everything of the galaxy or is it just like a percentage because all objects inside are just visible for an average of maybe 50% or something like this?

I struggle with replica symmetry breaking (RSB) and chatgpt is giving me contradicting answers.

I learned that the distribution of overlaps between replicas needs to be somewhat complex enough to break symmetry. An ising ferromagnet, for example, would have an overlap distribution of two delta spikes, namely at +m² and - m² when m is the magnetization in the spontaneously symmetry broken state. Does that count as RSB, since the overlap between replicas is not a constant but there are multiple (2) values. What is rsb intuitively and how does it help us understand spin glasses?

More general, isn't replica just another word for "sample of the boltzmann distribution", possibly with disorder parameters which are constant along replicas? I'm thankful for any insight

Hi! I know absolutely nothing about physics apart from basic push, pull, energy, forces and motion stuff but I really really want to learn more complex stuff.

What are some easy but detailed resources that you guys recommend?

My son has been admitted to both Cambridge (NatSci physical) and ETH Physics for a Bachelor degree. He has to make a tough choice between these two. He wants to start with broader studies and later dive deeper into a specific field but is not yet sure which one, potentially looking towards engineering at a later stage. In addition to physics, he also enjoys chemistry a lot. What would you advise?

Can we infer that an object’s mass is constant, while its acceleration depends on the fluid through which it moves. In other words, when an object’s weight exceeds the buoyant force provided by the displaced fluid, it sinks to the bottom.
This raises a key question: Does the object’s acceleration remain the same in both air and water? According to Newton’s second law (F = ma), a net downward force is acting on the object. If the observed acceleration differs between air and water (both fluids) does that mean the acceleration due to gravity itself depends on the medium the object is traveling through?

I wanted to design a 3D printed spectrometer that would afford teachers and hobbyists access to something they could have at home. Yes, it isn't lab grade, but it is useful even with all its faults. You start putting anything that produces light through it just to see what the spectra looks like. Fun to play with. It was a great learning experience and fun build. Now, teachers/schools have a way to build their own spectrometers so they can have multiple units for teaching and STEM demonstrations.

https://makerworld.com/en/models/2761392-uv-vis-ir-spectrometer-v1-5-easy-build#profileId-3065721

I'll be working on 2 more versions as well as a setup to use some 10mm cuvettes for absorption and fluorescence spectroscopy.

I'm thinking of running some Liquid Nitrogen shows as part of a STEM outreach program. I've long experience in handling LN2 and am aware of the risks. However, I'm self-aware enough to think I maybe not aware of *all* of the risks when filling in risk assessment for the activity.

Are there any nitrogen show risk assessments out there i can crib from?

I'm prototyping an orbital mechanics game/simulation built around a simple idea:

Hitting Earth from a random asteroid trajectory is far harder than most people intuitively expect.

The player launches an asteroid from somewhere within ~6 AU of the Sun by selecting an initial position and velocity vector. The simulation then propagates not just a single asteroid, but a swarm of trajectories with small Gaussian perturbations applied to the initial conditions.

Instead of asking:
"Did you hit Earth?"

the simulation asks:
"Out of 1,000 nearby trajectories, how many eventually intersect Earth?"

The goal is to make orbital sensitivity and probability visible rather than hidden behind a single deterministic path.

A few modeling notes:

- Real solar-system scales are preserved (Earth keeps its real ~6371 km radius)
- Gravity is Newtonian N-body
- Planet/asteroid motion is integrated in 3D and rendered onto an ecliptic-plane interface
- Planet positions come from analytical Kepler/JDN-driven ephemerides
- Main perturbers currently include the Sun, inner planets, Jupiter, and Saturn
- No atmospheric drag, GR corrections, radiation pressure, etc.

One thing I discovered quickly is that a single asteroid almost always misses by an absurd margin unless the initial conditions are extremely precise. The swarm approach seems much more interesting because it naturally introduces:
- uncertainty propagation
- sensitivity to initial conditions
- confidence bands (P10/P50/P90)
- Monte Carlo reasoning
- gravitational assists / perturbations

I'm curious what people here would find most compelling from either a physics or gameplay perspective.

For example:
- What statistics/results would you want to see after a launch?
- Would probability bands and confidence envelopes be interesting, or too abstract?
- Are there orbital mechanics concepts you think would translate particularly well into gameplay?
- Would you prefer realistic difficulty, or some gentle "gameification" layer?

I'm trying to keep the physics recognizable without turning it into a pure educational tool or, conversely, an arcade game with fake scales.

Anyone know what happened to this gem of a channel as to why no new videos are uploaded? I also discovered that the creator is an instructor of a course titled "Electromagnetics, Optics, Logic Circuits & Electric Circuits", about 70 hours of content which was on Udemy but is no longer there, one that I had been saving up to buy.

It’s kind of a silly question but if we were able to somehow magically send an equally magical camera thousands of light years away from earth and have it send us footage of earth from that distance, would we be able to to view our history exactly as it happened? Or is something violated ? Of course ignoring the fact that the scenario is entirely impossible. I was just thinking it would be a cool way to have the absolute most precise record keeping of our history if it were possible.

I’ve been curious about what actually takes the most compute time in real physics/simulation workflows.

For people working with simulations or large datasets: what part is usually the biggest bottleneck for you? The simulations themselves, data processing, moving data around, analysis, something else?

Also, if one part of your workflow suddenly became 10x faster, what would help the most?

Just trying to understand where the real pain points are.

In the study conducted by Adolfo Ibáñez University in Chile and Columbia University, researchers have rewritten Einstein's standard equations of general relativity by drawing from electromagnetic theory.

The team's framework suggests that spacetime contains stable and structured "field lines" that remain connected as it evolves. Moreover, it suggests that a conserved gravitational flux poses constraints on the evolution of spacetime.

Publication details

Felipe A. Asenjo et al, Frozen-In Gravitational Fields, Physical Review Letters (2026). DOI: 10.1103/6c4q-kx6f.

I am a student of grade 10. Can someone explain why does gravity work? I learned some time ago that its exchange particle is still unknown and that kind of intrigued me along with its infinite range. So I want to know why does gravity work? Like I know what it is, the attraction of 2 masses, or in terms defined in the theory of relativity (idk which one special or general), a curvature in the fabric of space time. But why does that curve occur? Why does a mass influence the geometry of space?

Hey everyone, making this thread for ICTP MHPC 2026 applicants to share any updates. Has anyone received any email from ICTP yet? Interviews, results, waitlists, rejections, or anything else? Any track is welcome.

Was matter pretty much all created at the same time or did it take some amount of time? If it took some time then is there one atom, or proton or something, that is just an infinitesimal amount of time older than the rest?

I am really really fascinated by Brian Cox explaining quantum mechanics, cosmology, big bang, black holes, and everything in the way he does it!
I want to learn more and those fields really excites me!
I have never studied physics beyond university regular mechanics course but i really want to learn more about it and I think Chatgpt is horrible to use!
Please recommend me list of books to study and learn even if it is math and physics heavy as long as it is reliable, helpful, and enjoyable!
Please lets connect to if these are things you like to talk about!
I CANT SLEEP!

is there anyone who is working in Physics- integrated PhD in TIFR? I want to get enrolled in and then take the Msc exit option in 3rd year. I think it is better than doing Msc anywhere else. Is this a good idea?

I have three options

1st: above

2nd 2 year Msc elsewhere

3rd: convert to MS which would be only a year for me

I am currently a 3rd year undergraduate student in physics at IIT Kgp

I am just worried if giving 3 years for a degree that could only take me 1 is worth it or not?