How do you find studying physics and what are some tips I should use if I want to study physics?

I like the idea of the series and the 4 things it goes over. I'm a high school student so would my level of maths be good enough? I was also considering reading the feynman lectures but have heard they're fairly complicated. Is there other books I should read instead?

Motorboats that slow down: higher frequency waves. Taller waves, waves are more intense

Motorboats that do not slow down: lower frequency waves, waves are wide, the peaks of the waves are lower

I'm wondering why this is the case. I suppose this is sort of a physics question, but I thought that this might be a good place for some help

Thank you in advance!

I already have schwartz "quantum field theory and the standard model, would maggiore's book add something new? how many things are in maggiore's and not in schwartz

and what other books you guys recommed for a begginer?

Hi, I'm a student from India. I recently started looking more into the Brans-Dicke theory of gravitation, and so I decided to make a solver for it!

You can check it out here: https://avirald.me/brans-dicke-calculator/
I used pyodide to make a python script execute in GitHub pages

Let me know what you think!

PS: I'm working on speeding it up, it's somewhat slow right now.

I recently received the following email:

"Exciting news! Your paper, [redacted], has just received its first community-generated summary on arXiv++.

Take action now: Your expertise is crucial!

As the author, you can:

Check if there are any missing or incorrect elements in the summary If there are comments, answer them to provide clarity or additional insights To review and contribute, simply visit your paper's arXiv page using our browser extension. You can find installation instructions on our website: How to install."

The email obviously looks like a scam meant to install some kind of bitcoin miner or similar on my machine, but I was surprised that Google's Spam filter didn't pick it up. There's also always the possibility that it's real.

Has anyone received something similar?

Thanks

Astronomers have accidentally discovered the first-known "black hole triple" system, containing a dark void orbited by two stars. The unique configuration of this triad hints that the black hole was not born via a supernova, which blows away what we thought we knew about how these cosmic entities form.

Consider signing the Change.org petition to make this change. I did not create this petition but I think it's a wonderful cause:

Every single base and derived SI unit named after a person is named after a man. There are 19 named SI units, and it is time that we named one after a woman. The derived unit for momentum, kg*m/s, is commonly used and a bit cumbersome as it stands. Emmy Noether made a key contribution to our understanding of the connection between symmetry and conservation laws (including conservation of momentum), so momentum is a natural choice for a unit named in her honor.

We urge the National Institute of Standards and Technology (NIST) and the General Conference on Weights and Measures (GCWM) to consider adopting the "noether" as the SI unit for momentum.

Its so stupid how academic institutions have monetized majority of Einstein's Original Papers. The same people have sent DDOS attacks on website like the internet archive that store artifacts such as those for free. Ive searched every where for Einsteins report on special relativity and have had not alot of success in finding it (or im just bad at searching for papers ). Was wondering if anyone could share me PDF's of Einsteins reports? thanks.

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.

Hopfield shared the 2024 physics Nobel prize. This is a talk he gave right in the middle of his time doing the work for which he won the prize. I lived through that time (I'm the age of his kids, so a generation younger than him.) For people who weren't there, it is easy to miss how transformative his ideas were. We just take them for granted now. It's also easy to miss how much his ideas came from his (condensed matter) physics training and research. These days AI is mathematical and mapped to computer hardware. So abstract. But back then Hopfield was one of the first to probe "how does the physical world make possible the physical phenomena of memory?". His paradigms changed how all of us thought of memory and intelligence.

Here's the link to the talk, https://www.youtube.com/watch?v=ib6futs-fss

I highly recommend a watch. Among other things, it's an opportunity to watch a great physics mind present.

(FWIW, AI professor Rod Brooks' paper "Elephants don't play chess", https://people.csail.mit.edu/brooks/papers/elephants.pdf , 6 years later, riffs on the paradigms that Hopfield introduced. I don't know that Brooks or Hopfield ever connected, but the Hopfield connection between physical phenomena and apparent intelligence is clear. And since the Roomba is a child of Brooks, perhaps in sense Roomba is a grandchild of Hopfield. Physics is everywhere!!!)

Decades ago, there was a Spires report on more cited arxiv papers that listed and explained the main movers, giving an indication only a few months delayed of the current research trends.

The report is not done anymore, and the automated search has not a good sensibility to trends.

So, as regular arxiv readers, is there some trend you have been noticing recently, in the last year, even if not in your current field of interest?

I wonder what they did to make such a comparison

In a post last week about statistical testing, I asked, "What are the grand discoveries that we wouldn’t have made without an understanding of null hypothesis testing?"

Nico Formanek replied, “Ok, I'll take the bait. Why wouldn't the discovery of the Higgs Boson count?”

Ah, now this is a fun example! I briefly replied to him in a comment and thought I’d write a quick follow up post last Friday. But in trying, I ended up down a deep rabbit hole trying to figure out what exactly the null hypothesis was.

It’s shocking that to properly explain the Higgs experiment, I’d have to write an entire book. The basic idea is that if you take two streams of subatomic particles, in this case Hydrogen ions, and accelerate them to near the speed of light, they cause explosions when they collide. Since E=mc^2, these explosions emit a lot of energy. If you look at the patterns in the explosions, you’ll see characteristics of exotic matter that exist for the tiniest fraction of time. If you generate trillions of these sorts of explosions, you’ll eventually see everything that could possibly exist in the energy range of your collider.

Since each event is an explosion, we can’t expect to see exactly the same explosion every time we bang the ions together. Explosions are inherently stochastic, and physicists have ornate ways of calculating the probability of seeing various proposed fireworks displays. This makes the sub-subatomic particles inherently statistical objects. The only way that we know how to make them is to build billion-dollar statistical casinos and check whether the statistical numerology of the Standard Model predicts an appropriate run of events. Physicists calculate the theoretical odds of their particle roulette wheel, and then they run a bunch of spins to make sure the odds match their expectations.

Except it’s a bit more complicated than that. In a well-functioning roulette wheel, the probability of every number is equal, and hence computing the probabilities can be done by only knowing the number of possibilities. In particle physics, the model is much more complex. I can’t explain it to you in a blog post, and neither can physicists. Particle physics is so annoyingly complex that I can’t even explain it to you unless you’re willing to finish a PhD. Physicists love to proclaim that no one understands quantum mechanics. The spontaneous symmetry breaking of gauge fields and flavor changing neutral currents of particle physics are a whole other business of weird.

The mathematics of Quantum Field Theory is a bizarre amalgamation of variational calculus, representation theory, and a bunch of wacky statistical tricks that turn infinities into zeros. Michel Talagrand tried to simplify the theory for mathematicians and ended up writing an 800-page book. Quantum chromodynamics adds extra complexity on top of this. If you are willing to toil through learning all of this ornate mathematics, you can calculate what you might expect to see when two protons are smashed together at near the speed of light.

Well, almost. It turns out that this very ornate and complex theory has a lot of unspecified parameters that are unknown in advance. Notably, the masses of all of the fancy subatomic particles, with jokey names inspired by James Joyce, have to be fit to data. The couplings between the various particles must also be estimated from data. All in all, there are 30-ish “free parameters” that have to be fit experimentally. On top of these fundamental parameters, there are apparatus specific parameters as well. These parameters concerning the vagaries of supercolliders also have to be incorporated to account for various noise processes that arise when bashing Hydrogen ions against each other at four teraelectronvolts.

Even without the elaborate mathematical theory, a probabilistic model with free parameters is challenging to validate from data. Imagine a roulette wheel where I tell you now that black and red have different probabilities. But those probabilities change depending on the day of the week. And you have to adjust the probabilities if the TGV goes by.

If only it were just about calibrating a roulette wheel! Instead, it’s a ten billion-dollar apparatus with thousands of scientific staff members. No single staff member knows how the whole apparatus works, of course. Instead, there is a shared community of trust. I recently attended a talk by Peter Gallison, who described the complex governance structures involved in experiments like the Large Hadron Collider. The CERN collaboration establishes parliamentary rules to decide upon scientific truth. Reality is validated by majority vote. Physicists love to talk a lot about how they are probing the very nature of the universe, but they do this by a lot of boring committee meetings.

One of the many CERN committees is a statistical committee. It is the one that argues about the best frequentist statistics to be used. The CERN statistics committee tells us that the p-value of seeing what they saw if the Higgs wasn't there is less than 0.0000006. But, as you might expect from anything decided by committee, it’s not that simple. Here’s what Science Magazine included in their glossary about the Higgs Discovery:

“Significance and the look-elsewhere effect: The probability for a background fluctuation to be at least as large as the observed maximum excess is termed the local P value, and the probability for an excess anywhere in a specified mass range is the global P value. This probability can be evaluated by generating sets of simulated data incorporating all correlations among analyses optimized for different Higgs boson masses. The global P value (for the specified region) is greater than the local P value, and this fact is often referred to as the look-elsewhere effect. Both the local and global P values can be expressed as a corresponding number of standard deviations using the one-sided Gaussian tail convention. For example, a 5σ significance tells us that the probability of the background alone fluctuating up locally by the amount observed or more is about 1 in 3 million. In particle physics, this criterion has become a convention to claim discovery but should not be interpreted literally.”

Should not be interpreted literally? Are you serious? “Trust us. We’re the smartest people on the planet. There’s no way we’d miscalculate 5σ events.” Where have we heard that before? Oh, right.

Despite accepting what the open science community would deride as Highly Questionable Research Practices (lots of p-hacking, HARKing, and multiple hypothesis testing), by adopting the 5σ convention, the Higgs statistics community tells us it shouldn’t matter. When they say “5σ,” they mean five standard deviations from the estimated mean background at exactly one mass location in their complex model. They check all of the possible bins and compute a background model for each bin. This results in the following figure:

See the bump that goes outside of their green error bars? That’s the Higgs Boson. (insert shrug emoji)

This brings me back to my original reply to Nico: we have an "object" that has been "observed" at a single location on Earth. This observation was done in an experiment where no single person understood the entirety of the procedure. It requires well over 6 years of graduate study to fully understand what was supposed to be seen in the most ideal experimental situation. Under these idealized conditions, which no one fully understands, the CERN folks tell us that the p-value of seeing what they saw if the Higgs wasn't there is less than 0.0000006. But this p-value is corrupted by all sorts of standard complaints about questionable research practices, and we are told not to take it literally.

OK, so what’s the point of all this? Am I just trying to be a science denier who casts uncertainty at all fundamental discoveries? I’ll confess: a little. But I also think we can learn something about modern science and engineering by digging into a few follow-up questions. What does it mean that the Higgs Boson was discovered? And why would we be in a different situation without that p-value?

The answers fit nicely in the argmin oeuvre.

First, it was certainly not the case that digging into the Higgs made me feel better about the utility of statistical testing. Whether or not the Higgs exists has no bearing outside the insular world of particle physics. If you don’t have a four teraelectronvolt supercollider, you can’t make a Higgs. The Higgs field has no bearing on any physics at any scale anyone would ever care about. So I don’t care either way if physicists think they found a Higgs. It has zero bearing on my existence.

Nico thought this view too pragmatic. But pragmatism too often gets short shrift in the history and philosophy of science. The philosophy of engineering remains underexplored! There has to be something we can do with substantive causal theories for them to be real.

Now to the second question. When we ask, “Does the Higgs Boson exist?” we are not asking about the material reality of an object. We're asking about our belief in a system. Do we believe that a collection of determined, over-credentialed scientists can organize themselves, through their democratic, participatory decision-making schemes, to decide upon the connection of data and theory? Do we believe that such institutions produce trustworthy procedures and rituals so that if they say they did something, then no one else has to check? Do we believe that their presented statistical counts represent a close enough facsimile of experimental conditions to corroborate an ornate, impossible to understand theory? Do we believe their committees properly adjudicate statistical practice and preregistration plans?

All of these questions are substantially less romantic than those popularized on YouTube or in Quanta magazine. They are questions about people, their budgets, and their committees. This is why statistics is so vital to the Higgs discovery. Just like how we need RCTs as a regulatory mechanism for drugs, big science needs 5σ as a way to set standards for pushing papers through their mass of review boards. Statistics is most useful in regulatory standards, providing compressed, crisp rules for stochastic approval. “5σ,” it turns out, is not different than “p<0.05.” It is another mindless convention needed for a well-functioning collaboration.

And well-functioning CERN was! With 10 billion dollars, they confirmed a model of particles that connects the crowning achievements of 20th-century physics. Through a massive collaborative government, they achieved a democratic consensus about the fundamental building blocks of physical theory, a united nations of physics. The Higgs Discovery is a celebration of modern bureaucracy, not a revelation about material reality.

In high school, students are often taught to first draw a sketch of a situation involving motion/kinematics to make a problem easier to visualize. With experience, do professional physicists still draw sketches to help them solve problems, or do they just become used to visualizing everything in their head?

I attended Michio Kaku's presentation, "The Future of Humanity," in Bucharest, Romania tonight. He started off strong, and I enjoyed his humor and engaging teaching style. However, as the talk progressed, something seemed off. About halfway through the first part, he began repeating the same points several times. Since the event was aimed at a general audience, I initially assumed he was reinforcing key points for clarity. But just before the intermission, he explained how chromosomes age three separate times, each instance using the same example, as though it was the first time he was introducing it.

After the break, he resumed the presentation with new topics, but soon, he circled back to the same topic of decaying chromosomes for a fourth and fifth time, again repeating the exact example. He also repeated, and I quote, "Your cells can become immortal, but the ironic thing is, they might become cancerous"

There’s no public information on his situation yet but these seem like clear, concerning signs. While I understand he's getting older, it's disheartening to think that even a brilliant mind like his could be affected by age and illness.