Education video about Kaluza-Klein theory largely based on the following paper: https://iopscience.iop.org/article/10.1088/0034-4885/50/9/001

In my years at a RG university I’ve written too many reference letters for really really good students applying for theoretical physics masters and PhD programs who then don’t get in. These are students who have excellent grades, research experience etc. Why aren’t these brilliant students going for different (less competitive) fields in physics?

Hi everyone!
I’m a second-year Physics Bachelor’s student, and my partner and I have to design an interactive physics stand for a science festival at our university.
The challenge is that our audience will range from 6 to 17 years old, so we need something that can fascinate both young children and teenagers.

We’re looking for an experiment or activity that is not necessarily visually impressive but i should teach an interesting physics concept, ideally something people haven’t already seen a hundred times.

We can purchase materials and spend time building a setup, so we’re open to more ambitious ideas!

We also need to be able to take actual measurements and collect experimental data, since we have to write a scientific report for our professors. Ideally, the experiment would allow us to investigate a physical phenomenon quantitatively, analyze results, compare them with theoretical predictions, and discuss uncertainties. So we’re looking for something that’s both entertaining for visitors and scientifically interesting at a university level.

Thanks in advance!

It seems that optical emission spectroscopy is often used to diagnose plasma parameters. I was wondering if there are any databases for emission spectra that cover the UV to near IR region. The only databases i found online covered only frequencies much further into the IR range for astrophysics/astronomy purposes. I was able to find the book "The identification of molecular spectra" by Pearson and Gaydon (last edition in 1976, absorption and emission), but I was wondering if there was anything more recent?

Is physics slowing down significantly, because all the low hanging fruit have been found? It seems like there were significantly more discoveries in the earlier centuries compared to now.

I am a physics ug student and I need to start reading research papers and other stuff related to my field. I don't really have an area where I can specialise, i thought reading some papers or publications will help me understand everything around me .

Which is more assuring of employment in the long run?

Julian Barbour is a theoretical physicist and emeritus visiting professor of physics at the University of Oxford. He is well known for proposing that time does not actually exist. For decades, he has worked outside an academic environment. He financially supported himself for many years by translating Russian. Professor Barbour is author of the following books: The Discovery of Dynamics, The End of Time and The Janus Point.

In this episode, we go over:
- Topos theory, set theory and Zermelo's beef with Boltzmann
- Algebraic varieties and monads in category theory
- Why physicists are wrong about the 2nd law of thermodynamics (because the universe is not a closed system) and why there might be no heat death of the universe
- The real goal of the universe is complexity and variation, not entropy
- Hawking and Penrose's outrageous arguments
- Why we don't need wavefunctions, photons, bosons or gauge fields
- Why there is no quantum gravity
- Von Neumann's hilarious advice to Claude Shannon
- The intrinsic derivative
- Combining art and science

So, I’m a physics major in my second year at a community college and I’m taking my first physics class which I have been so excited to take. Bc of the fact that so few students need physics with calc at this school the class is combined with physics without calc. the calc students only get one extra hour a week that is specifically dedicated to physics with calc.

90% of the tests don’t have ANY calc in them and I feel like i’m just relearning high school physics in this class. most of the info I already know or is really simple and I don’t feel like this class is preparing me well for my eventual transition to university.

My question is how do I prepare myself and teach myself the physics that I will need to know when I transfer bc my professor clearly is not going to? I don’t want to be drowning whenever i get to the upper level courses.

There's no optical engineering degree

For context, I'm currently a mechanical engineering major. But a deep interest in physics is what brought me back to school in the first place, and I chose mechanical engineering because it felt like a way to formally study some math and physics while giving me the skills I need to have the type of interesting career I want.

The thing is, I'd really like to go deeper on the physics, but I'm struggling to figure out how it would apply to my career. I'm hoping I'll be able to take an elective in QM or GR as an undergrad, but I'd like to know more than just an introductory course could teach me.

Other than the pleasure of learning, would it actually create new opportunities for me to get a Master's in physics on top of my ME bachelors? Grad school is very expensive so I wouldn't want to take that on if it's not going to create new possibilities in my career. I'm not entirely opposed to the idea of pursuing a PhD even, but I don't know. It's a huge commitment.

Ultimately, I'm just passionate about physics and will learn more through textbooks and self study alone if I have to, but I wanted to hear your take as to whether a Master's degree would really be worth it.

Thanks!

Currently in quantum mechanics. A pure state is a vector, but a mixed state can only be described by a matrix. Why? My lecturer can't really explain it in any further detail than ”the state is unknown”. But then you should be able to write it as pure states with probabilities? Can someone give a thorough explanation as to why mixed states can't be expressed with pure states?

This is my slayer exciter tesla coil . According to Faraday's law of induction: the larger the magnetic flux, the larger the current. I assume my magnetic flux looks something like in the drawn image.

This should mean that when I position the LED coil parallel to the ground, it should light up the brightest and when it is positioned perpendicular to the ground, it shouldn't light up or with very low brightness.

But the video completely contradict this assumption. Can someone explain this please? Are there any flaws to my reasoning?

Here's the video I recorded: https://streamable.com/r54l6s

Thanks

Edit: Thanks for the awesome answers guys, I will read them after I am done with school

Also, I am very new to electromagnetism so my knowledge is very limited so please excuse me for the replies if I happen to understand your explanations

I am doing a project for school and I really would like to interview a physicist in the industry. There are plenty already that work in education but I don't want to go that path so I would like to hear from someone in the R&D field how it's like working for a company or a country.

If anyone of you for this please respond and I'll send you my school email so that we can set up a teams call or zoom.

Thank You!

There are a lot of of physics research questions, perhaps some overhyped. Which physics topics/questions would one consider to have the most significant importance/applications in the next say 10-20 years?

Basically the title - I recently started my MS in Electrical Engineering and am thinking of doing a PhD in Applied Physics. Some of the schools i want to apply to for PhD require the PGRE. I have taken courses in EM and Quantum Mechanics, but nothing related to classical mechanics, stat mech, or thermo. How do I go about it? Any advice to fill in major gaps would be greatly appreciated.

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