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Physics. Please read all of the rules before posting. No HW, no career questions in top post.

The aim of /r/Physics is to build a subreddit frequented by physicists, scientists, and those with a passion for physics. Posts should be pertinent and generate a discussion about physics.

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Encouraged submissions

Open-ended discussions
  • Debates and discussions on all topics related to physics are welcome. Please make an effort to engage the community rather than simply state your views and expect others to validate them.

  • Shorter questions which are more straightforward to answer will get a better response in /r/AskPhysics.

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Encouraged in weekly threads

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  • Alternatively, try Physics Forums instead.

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  • New findings are always reported by multiple publications, and the fact that a specific link has not been submitted does not mean that this topic is not already being discussed on /r/Physics. Feel free to provide links to additional sources in the comment section instead.

Weekly schedule

All threads are posted at 9am EDT (1pm UTC).

Day Post
Mon What are you working on?
Tue Physics Questions
Thu Careers/Education Questions
Fri Resource Recommendations

How to use LaTeX?

First, you will need to install one of the recommended add-ons. To include an equation typeset in LaTeX in your post, put the LaTeX code between [; and ;].

[;i\hbar \frac{\partial}{\partial t} \Psi = \hat H\Psi;]


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Textbooks & Resources - Weekly Discussion Thread - September 22, 2023

This is a thread dedicated to collating and collecting all of the great recommendations for textbooks, online lecture series, documentaries and other resources that are frequently made/requested on /r/Physics.

If you're in need of something to supplement your understanding, please feel welcome to ask in the comments.

Similarly, if you know of some amazing resource you would like to share, you're welcome to post it in the comments.

13:00 UTC


Sensor as substitute for accelerometer in seismic activity detection application

I am trying to search on other sensors for accelerograph but the thing is that I can only seem to find that it only uses accelerometer. Are there any sensors that is beyond capable of accelerometer in seismic detection application?

I came upon fiber optic but the thing is that fiber optic cable is that it is installed underground to detect seismic activities. I am thinking of sensors that can be deployed or be installed in just surface level like a normal accelerograph does.

00:20 UTC


Thin Films Simulation, Using Monte Carlo

Heys guys,

Has anyone made a project about thin film simulation using monte carlo method. Or any other thing related to thin films.


15:51 UTC


Careers/Education Questions - Weekly Discussion Thread - September 21, 2023

This is a dedicated thread for you to seek and provide advice concerning education and careers in physics.

If you need to make an important decision regarding your future, or want to know what your options are, please feel welcome to post a comment below.

A few years ago we held a graduate student panel, where many recently accepted grad students answered questions about the application process. That thread is here, and has a lot of great information in it.

Helpful subreddits: /r/PhysicsStudents, /r/GradSchool, /r/AskAcademia, /r/Jobs, /r/CareerGuidance

13:00 UTC


Students: Is your university's math professors significantly nicer/cooler than your physics professors?

This is overwhelmingly the case at my school. Not to bash the physics profs. They are all very smart and talented. But the vibe of my physics department is very much "Doing physics is serious business". All my math classes (at least once you get past calc 4 and start taking higher math) are just like "math is fun!". All the math profs are super kind and open and feel like my friends, even if I don't actually know them very well (I'm a physics major). Which I can unfortunately say has almost never been the case in my physics classes.

This came up in a chat with my physics friends recently and I just had to ask if it was the same experience for others.

17:17 UTC


Is fusion energy actually feasible or economically viable?

16:22 UTC


Let's discuss Computer Algebra Systems

I rarely delve into Computer Algebra Systems (CAS), but when I do, I want it to be reliable. I've often turned to Mathematica in the past, but I find its user interface to be pretty unintuitive. My encounters with MATLAB during my undergrad days didn't leave me with fond memories either.

Today, I stumbled upon Julia's "Symbolics" library. What caught my attention immediately was its open-source nature and the ease with which I could script and utilize it from the shell. However, I couldn't help but notice, purely by intuition, that it appeared to be on the slower side.

Now, I'm curious to know: What's your go-to program for handling CAS tasks?

17:59 UTC


Physics Questions - Weekly Discussion Thread - September 19, 2023

This thread is a dedicated thread for you to ask and answer questions about concepts in physics.

Homework problems or specific calculations may be removed by the moderators. We ask that you post these in /r/AskPhysics or /r/HomeworkHelp instead.

If you find your question isn't answered here, or cannot wait for the next thread, please also try /r/AskScience and /r/AskPhysics.

13:00 UTC


What is your research area and why should people consider entering that field?

I don’t think I’m alone as a student that hasn’t decided on a specific field of research, so I thought it would be interesting to hear from those in research about their field of study and why someone should consider entering it.

Additionally, what’s one thing that fascinates you about your field, and what’s the biggest unsolved problem that your field of study faces?

12:57 UTC


What are you working on? - Weekly Discussion Thread - September 18, 2023

Hello /r/Physics.

It's everyone's favorite day of the week, again. Time to share (or rant about) how your research/work/studying is going and what you're working on this week.

1 Comment
13:00 UTC


Fireball Above Iceland

07:52 UTC


What produces a constant 9.7-9.8kHz noise at -85dB?

I downloaded an app that has a bunch of physics related items in it (magnetometer, compass, etc.). One of the items is a spectrogram/spectrum analyzer. Ever since I've had it, I've virtually always had a constant low decibel (~-85dB) 9.8 kHz tone. It's almost always strongest at home. However, I've picked it up more faintly even out in the middle of nature near my home.

I've popped it on a couple of times at work, however, I have not seen that tone while at work.

I have seen it fluctuate between nearly 10kHz and closer to 9.2kHz, but never ocillating around, always a constant tone. I've also noticed that sometimes it has a "pulse", as seen very faintly in the attached image. Screen shot was taken while phone was laying on my computer desk, not moving.

I'm very curious as to what could possibly be causing this, even out in an area without any housing nearby. Google searches have come up empty.

Thanks in advance for any light you may be able to shed on this!

22:41 UTC


IBM's 7 qbit computer

Has anyone used it to actually calculate something because I\m having a problem at actually creating useful circuits without creating an error. What have you used it for?

Also it seems I can make circuits that give different results for the same calculation. So what's up with that, is it just an optimisation algo finder?

18:36 UTC


Building a replica of Faraday's motor

14:50 UTC

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