/r/Physics

The aim of /r/Physics is to build a subreddit frequented by physicists, scientists, and those with a passion for physics. Papers from physics journals (free or otherwise) are encouraged. Posts should be pertinent, meme-free, and generate a discussion about physics. Please report trolls and incorrect/misleading comments.

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.

IRC Channel: #physics on irc.snoonet.org
chat with us

# 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.

• Links to papers in physics journals (free or otherwise) are welcome. Pre-prints are accepted, but moderators reserve the right to delete any posts that break the rules regarding unscientific content.
##### Science journalism
• We invite links to all websites, but article and blog post submissions require proper sourcing from the literature or mainstream scientific journalism. The lack of quality sources is grounds for removal at moderator discretion.

• If you are posting a link to your own website, please familiarise yourself with the global rules on self-promotion.

# Discouraged or not allowed

### Homework problems

• Questions that are specific homework problems or calculations should be redirected to /r/AskPhysics or /r/HomeworkHelp. Neither asking nor assisting with homework is allowed here.

• Alternatively, try Physics Forums instead.

### Unscientific content

• /r/Physics is a place for the discussion of valid and testable science, not pet theories and speculation presented as fact. We aim to be a welcoming place for both academics and the general public, and as such posts with no basis in the current understanding of physics are not allowed as they might serve to misinform.

### Sensationalised titles

• The title of your submission should accurately reflect its contents. If in doubt, use the title of the original research.

### Low-effort image/video posts

• Off-topic images, videos, or otherwise "zero-content" submissions are not allowed. Consider posting to /r/PhysicsJokes, /r/PhysicsGifs, or /r/ScienceImages instead. If you make an image/video post, you should make a comment in the thread describing the relevant physics, linking relevant literature, any computational methods used, etc. This will serve to generate on-topic discussion, and separate your post from low-effort spam. For more information on rules related to these posts, please see this thread here.

### Duplicate posts

• Please make sure that a submission on the same topic has not been posted already.

• 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;]

/r/Physics

1

#### How does electroweak burning work?

I've known about the electroweak force for quite a bit of time, but I haven't really investigated it until I discovered this goofy-ah thing called electroweak burning that TURNS QUARKS INTO ANTILEPTONS! It also emits a massive amount of energy (9 quarks -> 3 antileptons + 300 GeV), and according to my (very crudely done) calculations, 1 gram of hydrogen contains the necessary amount of quarks that, using electroweak burning, is capable of releasing ~9,000,000,000,000,000 joules or ~2,000,000 tons of tnt worth of energy (the bomb dropped on Hiroshima was only 1,500 tons of tnt). This shouldn't be possible because that is ~100 times as efficient as using perfect mass-energy conversion.

Basically, how the hell does electroweak burning turn a quark into an antilepton, and why is it so efficient!?

2023/03/27
00:02 UTC

837

2023/03/26
17:52 UTC

884

2023/03/26
05:15 UTC

6

#### Textbooks & Resources - Weekly Discussion Thread - March 24, 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.

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

2023/03/24
13:00 UTC

904

2023/03/24
12:09 UTC

102

#### Which of these physics mysteries intrigues/perplexes you the most?

There remain several unanswered fundamental questions in physics. Due to field of study, professional obligations etc interest among them might vary for members of this sub. I wanted to see which of these mysteries confounds you the most and which one would you like solved the most - within your lifetime?

View Poll

2023/03/24
00:01 UTC

6

#### Careers/Education Questions - Weekly Discussion Thread - March 23, 2023

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

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.

2023/03/23
13:00 UTC

0

#### Simulation of uranium enrichment

So I have a pretty big assignment coming up about The Manhattan Project and nuclear bombs. In relation to that I need to make a "simple" simulation of a chain fission reaction in which I need to show what degree of enrichment of the uranium (U-235 or U-236, I'm assuming) is necessary to be able to construct a nuclear bomb in said simulation. And lastly, I need to explain how it could be made more realistic.

I have already received some code to work with, but I need to improve it. How would I go about doing that?

2023/03/23
12:25 UTC

625

#### Physicists (Especially Condensed Matter Physicists) Really Ought to Share More Raw Data and Scripts

The recent superconductor papers make it seem pretty obvious to me that the field needs greater transparency when it comes to publishing data. And it's probably not just condensed matter physics that can improve, it's probably most subfields. If you publish results based on some data, you should really do your best to publish the raw data and scripts that produced your results. For the recent superconductivity papers it really shouldn't be hard to share all of this data and analysis from start to finish.

I got my PhD in physics and now I'm in computational biology. Biology has got its own problems, but the fact that there are methods researchers in biology who specialize in data analysis means that there is a large push to get people to share data and methods online. Many journals now require a "data availability" statement about where/how the data will be available online, and genetics datasets are huge so most physicists don't have that excuse.

Here's a list of data repositories in physics and other fields where you can share your data: https://www.nature.com/sdata/policies/repositories

There's also Github for smaller datasets.

The goal of the methods section is to enable people reading your paper to reproduce your experiment or analysis. If they can't do that then you haven't done your job.

Sure, there are exceptions. Some datasets are going to be too large to reasonably share, but surely you could still share scripts and some processed data. I don't need to see every pixel imaged by your cameras, just the ones that are relevant to your results. Each subfield needs to come up with its own norms.

In recent years I have just created a Github page for each paper, post the data or links to the data, post the scripts, and post a readme that outlines how to generate the results of the data with the scripts. It's not that hard.

Someone on the other thread said something like, "Oh, I have gigabytes of data and an incomprehensible lab notebook, good luck sorting through all of that if I share it." But I feel like this is exactly the problem that data sharing is designed to prevent, and it's also basically scientific misconduct to not keep reasonable lab notebooks of your data.

When I was a physicist I did a bad job of this myself. I never shared data or scripts online. My PI would never have allowed it. I asked other research groups for the data they used to generate published images and they said no. Today, as an outsider, I think it's easier for me to point out the problems that existed back then, and it's possible for me to see where different fields can learn from each other now that I've been a part of both of them for so many years.

I really don't have any skin in the game anymore, except for the fact that I got into science because I thought it was more important than an exercise in story-telling and picture-making.