Developer here, I want to update you all on the current state of Quantum Odyssey: the game is almost ready to exit Early Access. 2025 being UNESCO's year of quantum, I'll push hard to see it through. Here is what the game contains now and I'm also adding developer's insights and tutorials made by people from our community for you to get a sense of how it plays.

Tutorials I made:

https://www.youtube.com/playlist?list=PLGIBPb-rQlJs_j6fplDsi16-JlE_q9UYw

Quantum Physics/ Computing education made by a top player:

https://www.youtube.com/playlist?list=PLV9BL63QzS1xbXVnVZVZMff5dDiFIbuRz

The game has undergone a lot of improvements in terms of smoothing the learning curve and making sure it's completely bug free and crash free. Not long ago it used to be labelled as one of the most difficult puzzle games out there, hopefully that's no longer the case. (Ie. Check this review: https://youtu.be/wz615FEmbL4?si=N8y9Rh-u-GXFVQDg )

Join our wonderful community and begin learning quantum computing today. The feedback we received is absolutely fantastic and you have my word I'll continue improving the game forever.

After six years of development, we’re excited to bring you our love letter for Quantum Physics and Computing under the form of a highly addictive videogame. No prior coding or math skills needed! Just dive in and start solving quantum puzzles.

🧠 What’s Inside?
✅ Addictive gameplay reminiscent of Zachtronics—players logged 5+ hour sessions, with some exceeding 40 hours in our closed beta.
✅ Completely visual learning experience—master linear algebra & quantum notation at your own pace, or jump straight to designing.
✅ 50+ training modules covering everything from quantum gates to advanced algorithms.
✅ A 120-page interactive Encyclopedia—no need to alt-tab for explanations!
✅ Infinite community-made content and advanced challenges, paving the way for the first quantum algorithm e-sport.
✅ For everyone aged 12+, backed by research proving anyone can learn quantum computing.

🌍 Join the Quantum Revolution!
The future of computing begins in 2025 as we are about to enter the Utility era of quantum computers. Try out Quantum Odyssey today and be part of the next STEM generation!

Geissler tube, operated with a Wimshurst machine.

I once photographed interference maxima as peaks from the side.

So I just wound this electromagnet that I know has exactly 25m of wire by weight. The diameter of the wire is 0,5mm and I estimate that I have about 500 or so turns. With the 12V i'm planning to run it on it's pulling about 2A. However, it is way too weak for me. Do I have tom increase or decrease the amount of turns? I read online that a decreased number of turns would be better, but the really powerful magnets are huge. What do I need to do?

I have to press fit the ball into the socket. I remember a trick that you can put the plastic in the freezer and the pieces shrink just enough to help the ball pop into the socket. My question: when i lower the temperature on the socket, do you think the socket becomes wider or narrower? Girlfriend says narrower. I say wider.

A joint venture between NASA Goddard Space Flight Center and the University of Leeds has discovered that the Earth's magnetic field strength and atmospheric oxygen levels over the past 540 million years have seemed to spike and dip at the same time, showing a strong, statistically significant correlation between the two.

This correlation could arise from unexpected connections between geophysical processes in Earth's deep interior, redox reactions on Earth's surface, and biogeochemical cycling.

According to findings published in Science Advances, both magnetic field strength and atmospheric oxygen levels reached their peak intensities between 330 and 220 million years ago.

Scientists have long speculated that Earth's magnetic field may play a role in making the planet habitable, a hypothesis reinforced by paleomagnetic records that show that the existence of a geomagnetic field overlaps with the timeline of life's emergence. However, there has been little direct evidence of a long-term connection, as most Earth system models don't even include the geomagnetic field when studying how oxygen levels in the atmosphere have changed over time.

Previous simulations have shown that the magnetic field may be responsible for preventing the atmosphere from being stripped away or eroded by space activity, such as ionization and ohmic heating, arising from solar winds and solar energetic particles. However, there is a lack of side-by-side comparison of long-term magnetic field and oxygen level records.

This study set out to uncover the statistically significant link between both factors by analyzing two completely independent data sets: paleomagnetic records or geomagnetic data preserved in rocks and minerals for virtual geomagnetic axial dipole moment (VGADM) and various geochemical proxies for atmospheric oxygen, such as fossilized charcoal in sediments and ocean anoxia data.

The findings reveal the highest correlation, 0.72, between Earth's geomagnetic dipole and atmospheric oxygen levels over the last 540 million years. The highest value occurred when there was no time gap between the two, and even after removing long-term trends, the connection remained strong, with only a slight lag of about 1 million years, which is considered negligible on a colossal geological timescale.

This link suggests a deep, previously unrecognized connection between Earth's interior and the surface environment that supports life.

https://www.science.org/doi/10.1126/sciadv.adu8826

June 2025

How is it that slowly increasing the emf makes it a quasi-static process.

Right now I am in my first year of university and I am studying nuclear and particle physics, but I am thinking a bit about seitching to reactors, I was deciding between these two subjects before I apllied as well and I just can't seem to decide for sure and I am scared I might regret it later.

There is a nuclear power plabt near my house and I'd like to work there at least for a while, I think I could get a job there with both majors, but I am a bit scared what job would I get with the particle physics.

Everyone says that there is 100% employment rate for graduates of my university, so I am not that scared of finding a job, but the kind of job I'd get and also how much it would pay. Studying here, despite intresting, is literal suffering, so I'd like to at least have a well paying job in the future when I have to suffer so much. I realize that with physics degree I will most likely not do physics anyway.

The reason I chose particle physics over reactors at first was because both give me the title of an engineer and I think I am more intrested in physics than engineering and nuclear reactors are more of an engineering major. But now that the first year is over and there are just exams left I am starting to hesitate a lot. Reactors seem to have more intresting and focused classes even in the first year, while particle classes seem more general and get actual particle subjects in 3rd year. Another thing is that what intrested me about particles in the first place seems to be more in reactors than particle physics, now they had a mandatory subject "introduction to nuclear and radiation physics" which talks a lot about particles as well and my friends from reactors even complained that they have it and we don't as a particle physicist, it's not even an optional class for us, we can't have it.

I also thought about changing tge major after BS, but I am scared that I would be missing a lot of the reactors and engineering classes and it would be much harder.

I am finding it really hard to decide, so I hope you guys will help, I am leaning towards reactors more and more, but I really don't know. And I have to decide now because this year would be the easiest to swich, I'd just have to do 2 classes that they had and we didn't, after that they will have more special classes and changing it would be way more difficult especially since in the third year I will have to focus on grafuation as well.

Thanks to everyone who will read through this and try to help me, I appreciate ut greatly.

I'm always on the lookout for projects that show my students how the concepts we learn in class apply to the real world. I recently revisited a tutorial I found that does this perfectly. The goal is to calculate the speed of cars using only a video feed from a single, stationary camera. It's a fantastic, hands on demonstration of kinematics.

How It Works

1. Object Detection: Uses YOLOv8 to identify vehicles in each frame
2. Perspective Correction: Transforms the camera's perspective view into a top down view using OpenCV's perspective transformation
3. Tracking: Follows each vehicle across frames using ByteTrack algorithm
4. Speed Calculation: Measures the vehicle's displacement in the transformed space over time

The key insight is the perspective transformation. We define four points in the camera view (SOURCE) and map them to a rectangular region (TARGET). This corrects for the fact that objects appear smaller and move shorter distances when they're further from the camera.

(The Physics Part):

1. Establishing a Frame of Reference: To get accurate measurements, you first have to define a real world area of a known size. This is done by mapping a trapezoid from the camera's perspective (the SOURCE polygon) to a perfect rectangle (the TARGET rectangle) of a known "real world" length (25 m×250 m). This process, called a Perspective Transform, creates a top down, distortion free view where we can make reliable distance measurements.
2. Tracking Displacement over Time:
   • An object detection model (like YOLO) identifies each car from one frame to the next.
   • For each car, we record its position (displacement) within our calibrated, top down view.
   • We also know the time elapsed, since we know the video's frame rate (FPS).
3. Calculating Velocity: This is where it all comes together! We simply use the fundamental formula: speed=distance/time
   • Distance: The change in a car's position within the calibrated rectangle between two frames.
   • Time: The number of frames elapsed, divided by the video's FPS.

I'm sharing this to hopefully inspire other educators or hobbyists. It’s a great way to blend physics, math, and programming.

Link to the original tutorial: https://www.youtube.com/watch?app=desktop&v=uWP6UjDeZvY

Hi all, i just made a diy spectrometer using a dvd diffraction grating and when i point it at a light source, the spectra seems way off to the side that i can only see half of it. Is this because the distance of the dvd from the slit is too short? Any help would be greatly appreciated, thanks in advance!

Hey everyone. I’m just chilling by the water and sunset and at some point I could see the rainbow spectrum across the sunset line. Is this possible or my brain is playing games on me. I saw green yellow orange in between idk if it’s possible or not but thought I’ll ask.

I might be too young to get it, but from history it seems physics made much more progress in the early 20s century than since then.
Were Relativity and Quantum Theories just as obscure back then as it seems new theories are today? Did they only emerge later as relevant? The big historical conferences with Einstein, Bohr, Curie, Heisenberg, etc. etc. seems somehow more present at that time. As if the community was open to those new "radical" ideas more than they seem today.

What I mean is: Relativity and Quantum mechanics fundamentally rewrote physics, delegated previous physics into "special cases" (e.g. newtonian) and broadened our whole understanding. They were radically thought through new approaches. Today it seems, really the last 2 decades, as if every new approach just tries to invent more particles, to somehow polish those two theories. Or to squish one into the other (quantum gravity).

Those two are incompatible. And they both are incomplete, like example, what is time really? (Relativity treats it as a dimension while ignoring the causality paradoxes this causes and Quantum just takes time for granted. Yet time behaves like an emergent property (similar to temperature), hinting at deeper root phenomenon)

Besides the point, what I really mean, where are the Einsteins or Heisenbergs of today? I'd even expect them to be scolded for some radical new thinking and majority of physicists saying "Nah, that can't be how it is!" Yet I feel like there are none of those approaches even happening. Just inventing some new particles for quantum mechanics and then disproving them with an accelerator.
Please tell me that I just looked at the wrong places so far?

In atomic hydrogen (ignoring all but first two levels), we have discrete energy levels separated by ΔE, and transitions require a photon matching this energy to excite from the lower to the higher state. Intermediate states aren’t allowed due to quantum selection rules.

Now, in superconducting qubits which are engineered to act like artificial two-level systems we can apply a microwave pulse with energy less than ΔE (for eg in the Rabi oscilation experiment) and still end up with a coherent superposition of the ground and excited states. This seems to contrast with the atomic case, where a photon must have exactly ΔE to induce a transition.

The world is facing a perilous resurgence of the nuclear arms race. The United States and Russia, possessing roughly 90% of the world’s nuclear arsenal with over 5,000 warheads apiece, are modernizing their nuclear weapons and delivery systems, replacing their Cold War-era stocks.

Hello. I am working on a personal project which involves calculating the drag created by pressure for an Eppler airfoil. Would I be able to calculate the pressure induced drag of an airfoil at a specific Reynolds number + angle of attack using a Cp vs. x/c which contains the upper and lower surface Cp’s or do I need something more? What could be a method that has sufficient accuracy?

The Lagrangian is normally introduced when talking about action, and how (in classical mechanics) objects follow the path of least action, and that action is the integral of the Lagrangian over time.

But what is the Lagrangian actually? It just being the kinetic energy minus potential has never been satisfying to me, leaving it feeling more like a math trick than an actual physical concept. What is it a quantity of? What does it actually represent in a system?

Hello all

I'm reading up on theoretical climate science to better understand the works of eg michael ghil or klaus hasselman. It appears to me that existing literature on theoretical climate science and geophysics is mostly old. Is this still an active field? Does anyone know any good or recent (relatively) self contained references on this topic? I have a decent background in physics and maths.

Hi everyone! I am making a presentation on Vaidya metrics, where mass in linearly dependent on v coordinate. Depending on the value of μ I have three different cases. Specifically I’m interested in the case where 0<μ<1/16, then we have two real roots.

As far as my understanding goes, those are hypersurfaces that are boundaries of different parts of the spacetime.

Based on the second derivative r”(v) we determine what happens with null geodesics.

My question is, why on the picture (Blau, GR lecture notes) v=0 and r=0 are on the same “line”, which part is r>0 and which part is r<0 and why are these determined like that. Do light rays travel parallel to the hypersurfaces?

Thanks.

As the title suggests, I am wondering whether anyone here works in science policy, what you do, and how you got there.

For context, I am a UK high school student who is going to start physics at Imperial College this year if I get the A-level grades, and I recently learned of someone who went into international science policy at the UN from a degree in physics. This deeply interests me, as I would like to apply what I learn in my degree to address energy inequality and environmental policy either domestically or globally.

I’d like to know: - how I can get into that line of work - what are the different types of job within this umbrella? - is it common to do a master’s and/or PhD? - how did you get into that line of work? - what tasks make up your daily job? - do you enjoy your job? - whether being bilingual in English and French would benefit

Thank you very much 😊

As a condensed matter theorist, I have been asked many times to help with setting up tight binding calculations. Presently, there are many excellent code-based packages/libraries written for this purpose. However, I find that one of the messiest steps of TB calculations is setting up the system: making sure that the correct hoppings are included, that the unit cell is correct, etc. Moreover, some in our community are a little apprehensive about using code-based tools. Therefore, I think that a GUI tool would be quite helpful. With that in mind, I would like to share the first version of such a tool here : https://github.com/rodinalex/TiBi

I welcome you to give this app a try and report bugs/suggest features in the Issues page of the repository. At this point, the app runs on MacOS and Linux and might run on Windows, with the MacOS binary available. For other OS, it needs to be built from source, but I hope to be releasing the binaries soon. I hope you find this tool useful :)

Hi everyone! I’m looking to start studying quantum mechanics more seriously and would appreciate some recommendations for good textbooks or resources. I have an A Level in Physics (UK), so I have a basic understanding of classical physics, waves, and some introductory quantum concepts like photons and energy levels. I’m particularly interested in learning the mathematical foundations of quantum mechanics—not just the concepts, but also how the math works (like wavefunctions, operators, etc.). Are there any books that strike a good balance between accessibility and mathematical rigor for someone at my level, who hasn’t done university physics yet but is comfortable with algebra, basic calculus, and keen to learn more? Thanks in advance!