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So You Want to Learn Physics (2016)
- elcinr 8y agoREEEPOST!
- nhkssol 8y ago> One big problem is that a lot of the popular books written about physics (especially those by famous physicists) are incredibly speculative and tend to present an unrealistic view of what the study of physics is all about. This is irritatingly common in economics also though with economics it's less often speculation and more often simplification to the point that it becomes misleading. e.g. "black holes suck in matter around them". Many pop science physics books will make black holes sound unique in the way they are able to attract matter which misleads readers as it is just gravity being applied to a massive object.
- sleavey 8y agoI went to university intending to study computing science, but switched to physics half way through under the assumption that you could teach yourself computing science more easily than physics. I wouldn't change what I learned for the world, and I'm now in physics academia, but it's funny how my job these days involves using some of the algorithms, mathematics and data structures that I was just about to start learning if I had stayed the course in computing. My few years of study and general interest in computing has already given me a huge advantage in solving certain types of problem. I think computing science (not just software engineering) is slowly but surely becoming an essential part of many areas of modern physics research.
- nyc111 8y agoI agree. It seems to me that in those huge physics projects like CERN what most physicists do is programming or data analysis.
- nyc111 8y ago> computing science ... is slowly but surely becoming an essential part of many areas of modern physics research. Also, this means that fundamental assumptions and the calculations are hidden from view. Recently, some physicists questioned the findings of LIGO but if I understand correctly all is decided by data analysis software and outside teams have a disadvantage to decipher it.
- snops 8y agoThe LIGO result is actually excitingly available as an IPython notebook, which provides a tutorial to verify the data yourself, using entirely open source software. https://www.gw-openscience.org/s/events/GW150914/GW150914_tutorial.html https://www.gw-openscience.org/s/events/GW150914/GW150914_tu... The actual signal processing isn't that complex IMO. I don't know how open the LIGO hardware is, but it's very unlikely you would build one yourself to verify.
- pge 8y agoThis is very true - I was a physics undergrad and learned to code working in a project at cern. While the underlying physics was the foundation of the project, the day to day work was all coding: processing and analyzing the huge amounts of data coming out of the experiment.
- Koshkin 8y ago> a physics undergrad Now imagine dozens of people with a PhD in physics doing the same. (Earning a degree in physics is hard.)
- pge 8y agoyes, that was one of the insights of the work. The people working alongside me were post-docs that were still having to put in their time as workers on other people's research projects. Particularly, in the area of experimental high-energy physics, where accelerators were needed to do the work, everyone had to jockey to get time on the accelerator (even nobel laureates like the leader of the project I worked on). It seemed like every experiment was a compromise of different people's goals in order to combine together to get enough collective clout to get access to the accelerator to even do the project. That meant the guys who had already completed PhDs at prestigious schools were still pretty low on the hierarchy (but ten years older than me). The time spent working with those guys definitely influenced my decision not to continue with a PhD...
- renjimen 8y agoNot just research, but applied physics too - at least, that was my experience working in the defence and energy sectors. Looking back, it’s remarkable how little of my physics studies were devoted to learning about the computational techniques I spend the majority of my time working with.
- naasking 8y ago> I think computing science (not just software engineering) is slowly but surely becoming an essential part of many areas of modern physics research. I like to say that physics, mathematics, and computer science are the three pillars of human knowledge. There's some overlap between each pillar, and we don't yet fully understand how each of them fully relate to the others, but each is essential to gathering a full picture of any phenomenon.
- Engineering-MD 8y agoI think there must be more pillars than that. Biology and chemistry while related to physics are distinct (in the same way physics is not maths). More broadly, humanities and the arts are still valid areas of knowledge. Hacker news has a bias towards your three pillars, but I think it is important to acknowledge that human knowledge does go beyond CS, maths and physics.
- naasking 8y agoI disagree re: biology and chemistry. Certainly they are epistemically useful simplifications of the other pillars, but they are not foundational or fundamental. Physics is not math because it's an empirical rather than a priori exploration. We are trying to reproduce the function governing natural laws, where in mathematics we are exploring the properties of functions. Computer science in turn is concerned with the construction of mathematical structures via algorithms, and so physics will be one such construction. I think trying to place humanities and the arts under "knowledge" is a category error. These fields don't produce knowledge as its commonly understood, as a corpus of mind-independent facts and their relationships. Certainly facts appear in these fields, such as historical facts and authorship, but I don't think building a corpus of facts is not the main purpose.
- Koshkin 8y ago> simplifications of the other pillars This fallacy is called "reductionism."
- agumonkey 8y agoWait a bit, in a few years physical and computing models will merge. #my2ctsbet
- nyc111 8y ago> ...the pure joy of understanding the universe around us is one of the most beautiful experiences you can ever have in life. But you do not need to study physics for 25 years in order to understand how the world works. Academic physics that she wants us to learn to undersdand the world is just a new academic subject invented or formalized in the 19. century. Archimedes knew 0 (zero) physics and made huge discoveries. Galileo was not a physicist in the modern sense of the word. Even Newton was not a physicist but a natural philosopher. Physics today is a professional field. By studying physics textbooks you will only gain enough knowledge to pass physics exams. It's much better to go out and look at nature directly. If you need specific mathematics just learn that part, solve your problem and move on. But academic physics, as she clearly mentions,claims to build on previous knowledge. This is the way of scholasticism. Scholastics claim that without spending two years studying calculus you cannot invert a matrix. (Because they make a living teaching you calculus.) This is not true. Knowledge is not linear. I can study and learn matrix operations with zero calculus knowledge. The opposite of scholasticism is just-in-time knowledge. Whatever I need I can look it up. But thanks for posting this. There are good resources in it.
- FranzFerdiNaN 8y agoA lot of times you don't know what you need. The point of a good curriculum is to help you avoid those situations as much as possible.
- nyc111 8y agoIf the goal is to try to understand nature, make your own curriculum. Most people, myself included, initially believe the physics hype and believe that by studying academic physics they will gain new understanding of nature. I believe this is not the right way. It is better to start by asking a specific question. For instance, I am curious about what matter is. So I ask myself What is matter? and try to answer this question. I divide my question into smaller questions. Until I find a question easy enough to answer. I take it from there. But if I enter a physics curriculum in a university, I won't be able to ask this question for 20 years. The answer will always be in the future.
- joeblau 8y agoThis couldn't have come at a better time for me. I was listening to Kara Swishers interview with Elon Musk[1] and he touched on lots of physics related concepts related to all of his companies. The interview made me want to learn more about physics. [1] - https://www.recode.net/2018/11/2/18053424/elon-musk-tesla-spacex-boring-company-self-driving-cars-saudi-twitter-kara-swisher-decode-podcast https://www.recode.net/2018/11/2/18053424/elon-musk-tesla-sp...
- nyc111 8y agoElon Musk talks about arguing from first principles and claims this is the physics way without going into details. What else did he say about physics that you liked?
- joeblau 8y agoWhen he was going into the Boring companies tunneling evaluation trying to figure out weather current tunneling tech was power constrained or heat constrained. Also he mentioned the supersonic jet design that he has. There were also some undertones with the Tesla Roadster, Tesla Pickup truck and SpaceX BFR.
- nyc111 8y agoOk, thanks for giving details. But these can be classified more like engineering issues. I don't know if you agree.
- anonytrary 8y agoThe author recommends some interesting popular books: 1. The Feynman Lectures on Physics 2. The Character of Physical Law by Richard Feynman 3. Deep Down Things: The Breathtaking Beauty of Particle Physics by Bruce Schumm 4. The Particle Odyssey by Frank Close 5. Weinberg's The First Three Minutes IMO someone who seriously wants to learn physics should read these books after they have gone through the typical undergraduate university books (classical, E&M, quantum, stat-mech, etc.) I would not recommend reading popular books until after you already understand the basic ideas of physics. Popular science books are like dessert.
- cygx 8y agoThe Feynman Lectures are not pop science, but a textbook series based on his undergraduate courses.
- kgwgk 8y agoI agree, they belong in the “Undergraduate Physics“ section.
- anonytrary 8y agoI didn't mean to imply that The Feynman Lectures in particular were "pop science". They are more akin to a very condensed overview of an undergraduate curriculum with interesting motivating examples hand picked by Feynman. They are not a substitute for undergraduate courses, and I'd advise most students to read them after they finish their core undergraduate courses.
- fjsolwmv 8y agoThe Feynman lectures were specially designed for creme de la creme undergrads who already did a course in physics in high school. They are a terrible way for a noob to try to learn. Also strange that the author warns against exotic topics and then 3/5 of these recommendations are exotic things 99.9% of readers will never encounter.
- anta40 8y ago
- mathgenius 8y agoBooks are too low bandwidth. You will get stuck, mostly on trivial stuff. Then what do you do? My advice is to find a teacher. If they are any good they will speed up the process by one or two (or more) orders of magnitude. Even the professionals do this.
- antt 8y ago>You will get stuck, mostly on trivial stuff. Then what do you do? Find other books. There's a reason why university libraries have old editions of the same books and very similar books on the same topic.
- edanm 8y agoThis is great and, in my experience, non-trivial advice. I often used to get stuck on a mathematics textbook, and wouldn't know how to go forward. Turns out, sometimes different textbooks covering the same topic will be much better, or even just will be better for teaching one specific concept.
- dvfjsdhgfv 8y agoWhat works for me is to combine the two. I can absorb most things from books. Then, when I get stuck, I ask the advice of someone who knows. I was actually surprised how inexpensive this can be these days and how much a passionate teacher can give you these days in terms of inspiration and opening your mind to new perspectives regarding something you (thought you) already knew.
- commandlinefan 8y agoYeah - I dug out my old caculus textbook a while ago and started trying to work all of the problems in it. But there are a handful I just can’t get, no matter how long I work on them. It would be nice to give in and ask somebody who knows the material better than I do where I’m going wrong (although I’m sure it will probably be something stupid...)
- 8y ago
- nyc111 8y agoI'd like to say that Mach's Science of Mechanics is a timeless book and I would recommend to anyone who hopes to like physics. It's so different than modern textbooks. You get the feeling of learning new things as he explains each phenomenon with simple mathamatics and often ingenious ways. https://www.cambridge.org/core/books/science-of-mechanics/D8A72D6443150FDB4820DCA339836EB2 https://www.cambridge.org/core/books/science-of-mechanics/D8...
- Tomte 8y agoSusan Fowler's life story totally impresses me. She is world-renowned for MeToo/Time Person of the Year, but her achievements in physics through sheer will and hard work, even though her upbringings did not give her much in that direction, makes me think there is a movie in it.
- minhazm423 8y agowhat are her achievements in physics?
- d--b 8y agoBottom line is: work your ass off for at least 5 years, and maybe you'll have a chance to get it. At least, that's honest advice!
- albertgoeswoof 8y agoIf you work hard for 5 years you will get it, it’s not a chance
- d--b 8y agoMmh maybe you can learn enough to understand what people are talking about generally, but there is no guarantee that you will be any good at it
- Koshkin 8y agoWell, this depends on the level on which you want to be. A good way to start is with an elementary (i.e. non-calculus based) physics course. Despite being called "elementary," it might get you a long way towards learning a lot of non-trivial, often quite complex - and useful - physics. This could take a few months to a year. It will introduce you to vector algebra and the practical use of trigonometry. The next round would be a "general" course. It is the best chance to learn much of the "high-end" physics a "normal" person or an engineer will ever have. This course uses some simple ways of doing calculus and vector analysis, much of which will be explained as you go. Be prepared to spend a couple of years on this course. After that, you could cut your teeth into a traditional course on theoretical physics (e.g. Landau and Lifschitz). Not many people will end up there, and there may be little practical benefit for most of us. This course will require much of the traditional higher math. There is no telling how many years and how big an effort you will have to devote to this. And, finally, there's the "modern" theoretical physics, which is heavily based on modern (abstract) mathematics - very cool stuff indeed!
- anualvis 8y agoIs there a similar list for Mathmatics somewhere?
- andrepd 8y agoWell I disagree with many of the book choices, but if there's one thing that's absolutely spot-on is this: >One big problem is that a lot of the popular books written about physics (especially those by famous physicists) are incredibly speculative and tend to present an unrealistic view of what the study of physics is all about. When you're learning physics, it's good to avoid these types of speculative books, and stick to the good ones that talk about the real physics we know exists. Oh god yes. Why is it that whenever a lay person wants to talk about physics they talk about "11 dimensions", "string theory", or "time dilation", or any similarly crazy-sounding term that they read in a massively incorrect pop-sci article. Basically it makes it sound like physics is about all this crazy complicated and far-fetched ideas, rather than simple and beautiful principles to understand reality, which is what it is. I don't know if I managed to convey what I mean.
- cygx 8y ago> "11 dimensions", "string theory", or "time dilation" One of these things is not like the others...
- fjsolwmv 8y agoTo the average pop reader's digest human experience, they are pretty close. Sure, it's interesting to know that GPS is affected by time dilation, but the hours spent on thought experiments on intergalactic travel are a distraction from all the things one can learn about their everyday life.
- twtw 8y ago> all the things one can learn about their everyday life I'm curious what topics you have in mind? My everyday life is like 90% Newtonian mechanics, 9% thermodynamics, and 1% fluid mechanics (percentages completely made up). Or are you thinking like E&M for phones and stuff?
- kurthr 8y agoYeah, the frequency shift "time dialation" of Radar & Lidar for traffic tickets and even Time-of-Flight imaging for your FaceID all involve the constant speed of light or special relativity... but yes, all of magnetism can be derived as a special relativistic case of electro-statics (relativistically moving charges). For me, the more annoying aspect to this is that the "it's all relative man" has infected even more techincal discussions to the point where engineering and settled science is treated as just more "woo woo" by people who could know better.
- perlgeek 8y agoHaving completed a graduate level Physics education, I can attest that the selection of topics is solid. (Can't comment on the books, I learned in a different language where other books tend to be used).
- Tomte 8y agoAssuming it's German, would you like to list some of your favorites? I've noticed that I mostly read English textbooks on all kinds of subjects, because it's easier to get recommendations on HN or sites like chicmath.
- perlgeek 8y agoOh, it's been a long time :-), but I'll try to dig through my memory. I think I liked the Gerthsen, our Profs also recommended Demtröder, which was OK, but somehow I never liked it as much. In theoretical physics, Nolting and Fließbach were good -- though I cannot remember which topic I learned from where. I did my Diplomarbeit on spin transport in mesoscopic systems, and really liked "Electronic Transport in Mesoscopic Systems" by Datta, which at the time seemed to be the only accessible and clear writing on the subject. Disclaimer: I tended to go to the lectures very regularly, and mostly learned from there, so the books very mostly supplemental material for me.
- anton_tarasenko 8y agoAlso Landau and Lifshitz, Course of Theoretical Physics.[1] Released to public domain on archive.org: https://www.reddit.com/r/Physics/comments/1dmxq7/our_beloved_landaulifshitz_books_are_available/c9s774y/ https://www.reddit.com/r/Physics/comments/1dmxq7/our_beloved... [1] https://en.wikipedia.org/wiki/Course_of_Theoretical_Physics https://en.wikipedia.org/wiki/Course_of_Theoretical_Physics
- ivan_ah 8y agoWow what an amazing list. It will still take many years to learn all this material, but I think that a dedicated student could follow it and physics up big time! My time estimate for someone with normal intelligence level (i.e. not genius), starting fro scratch and learning part-time, would be 2-3 years. It's totally worth it though for the analytical power that learning physics gives the learner. Some notes/links below: > Before you begin studying physics and working through the topics in the sections below, you have to be familiar with some basic mathematics. That is very true and often a big obstacle for people who have been out of school for some time. Note it's not enough to just be familiar with the concepts—you must achieve fluency with the procedures so you can use them as building blocks for later studies. For example, it's not enough to just read about the quadratic formula (-b ± sqrt(b^2-4ac))/(2a) and use it a few times, spending 5 minutes each time to think about the steps, plugging in the vars, etc. Because solving quadratic equations is used so much in math and physics, you have to package that procedure as a reusable routine that you don't think about anymore and you can apply almost without thinking, in under 30 seconds. This "fluency with the basics" will ensure you're not slowed down when you reach the more advanced topics where solving quadratic equations is used.... and there is only one way to build fluency... > Regardless of your learning style, you'll still need to solve the physics problems in each textbook. Solving problems is the only way to really understand how the laws of physics work. There's no way around it. This. A thousand times this. I wish someone told me that when I was studying. It may not be fun to get stuck, go down the wrong path, doubt your abilities and feel stupid along the way, but that's what growth looks like. If every time you read a solution to a problem provided by someone else you gain one "knowledge unit," then finding the solution on your own is > 10 knowledge units. Forget 10x engineer, be a 10x learner—solve some problems! > 1. Introduction to Mechanics [...] the basics of motion in a straight line, motion in two dimensions, motion in three dimensions, Newton's Laws, work, kinetic energy, potential energy, the conservation of energy, momentum, collisions, rotation and rotational motion, gravitation, and periodic motion. > You'll need to learn calculus while working through University Physics. > Shameless plug, I wrote a book called No Bullshit Guide to Math and Physics that covers these exact topics. It would be a great starting point for someone who wants to review high school math and learn mechanics and calculus in an integrated manner. Here are some links if anyone wants to check it out: - preview: https://minireference.com/static/excerpts/noBSguide_v5_preview.pdf https://minireference.com/static/excerpts/noBSguide_v5_previ... - https://minireference.com/static/tutorials/conceptmap.pdf https://minireference.com/static/tutorials/conceptmap.pdf - condensed printable tutorial: https://minireference.com/static/tutorials/mech_in_7_pages.pdf https://minireference.com/static/tutorials/mech_in_7_pages.p... - reviews: https://www.amazon.com/dp/0992001005/noBSmathphys https://www.amazon.com/dp/0992001005/noBSmathphys
- musgravepeter 8y ago>Regardless of your learning style, you'll still need to solve the physics problems in each textbook. Solving problems is the only way to really understand how the laws of physics work. There's no way around it. Even though it can feel tedious at times, there's nothing more rewarding than figuring out a really difficult physics problem and realizing that you figured it all out yourself! This is the only way. It's I how I moved from an EE undergrad to a theoretical physics PhD. As I come back to material it's a lesson I need to painfully relearn. (Something I re-re-re-learned in 2015 http://nbodyphysics.com/blog/2015/02/28/learn-physics-with-this-one-trick/ http://nbodyphysics.com/blog/2015/02/28/learn-physics-with-t...)
- commandlinefan 8y agoCalculus, too. I wonder about the author’s implication that she actually worked every problem in all of those textbooks. I suppose it’s possible, but it would take a decade, at least, if you were working full time (and forget having any kind of a social life or, god forbid, a couple of kids).
- amelius 8y agoI'll just drop a link to Susskind's "Theoretical Minimum" course: https://theoreticalminimum.com/courses https://theoreticalminimum.com/courses
- tobmlt 8y agoGerard ’t Hooft goes here too I think: http://www.goodtheorist.science/ http://www.goodtheorist.science/ Though I think Susskind's lectures and books are truly the best starting point for say, an engineer who wants to go back and do physics from the ground up.
- melling 8y agoPrevious discussions: https://news.ycombinator.com/item?id=12691963 https://news.ycombinator.com/item?id=12691963 https://news.ycombinator.com/item?id=13684303 https://news.ycombinator.com/item?id=13684303
- Breadmaker 8y agoThe Mechanical Universe (1986) [video] https://news.ycombinator.com/item?id=17793483 https://news.ycombinator.com/item?id=17793483
- earthicus 8y agoA few more good pop physics books: Maxwell - Matter and motion. Written by THE Maxwell, what more do you need to know? long out of copy-write and available on the web for free Born - The restless universe. discusses atomic theory and describes some of the more down to earth parts of quantum theory, especially how the theory explains quantitative properties of atoms and the periodic table. Einstein & Infeld - The evolution of physics. pseudo-Historical exposition taking us from the mechanical universe to fields to quanta, and from Galilean relativity to Einstein relativity. Reichenbach - the philosophy of space and time. technically philosophy of science, not pop science, from the logical positivist school of the Vienna circle. very readable discussion of abstract mathematical geometry and various relativity principles, if you don't mind skipping some of the more bloviating bits. Pask - Magnificent Principia. Fantastic overview of Newton's Magnum Opus, although it doesn't give enough historical context to what newton was building on. Assumes some knowledge of calculus.
- dboreham 8y agoHmm...I think I have (somewhere) a copy of that Born book, signed by Born, courtesy of my Dad who I suppose must have run into him in Edinburgh in the 50's.
- abecedarius 8y agoA bit more on the Maxwell book: it's a real textbook rather than "pop physics" in the usual sense, but written for people with only a high-school level of math (algebra and geometry). Wonderful explanations -- for one, iirc, the derivation of Kepler's conic-section law which Feynman later rediscovered and presented in "The Motion of Planets Around the Sun" -- although the prose style is rather stuffy and Victorian, and Feynman has him beat there.
- earthicus 8y agoAre you sure we're thinking of the same book? The one i'm referring to [1] uses basic algebra (fractions, exponents, variables), only a couple of times in the entire exposition if i remember correctly. Its precisely what I would think of as good, non-fake popular physics. Edit: On second thought, I suppose this really isn't "popular physics in the usual sense" as you described it, so we probably are referring to the same text! https://archive.org/details/in.ernet.dli.2015.151311/page/n7 https://archive.org/details/in.ernet.dli.2015.151311/page/n7
- ivan_ah 8y agoFor more advanced topics, this is an amazing book that covers many graduate topics in a unified and consistent notation: https://www.amazon.ca/dp/0691159025 https://www.amazon.ca/dp/0691159025 Draft of the book is available here for free: http://www.pmaweb.caltech.edu/Courses/ph136/yr2012/ http://www.pmaweb.caltech.edu/Courses/ph136/yr2012/ Warning: this is very advanced material... I'm still on Chapter 1.
- mp3player 8y agoAs a new-comer to the topic of manifolds, learning it from math textbooks is painful. That seems to be the case even if you're reasonably strong at analysis, topology and linear algebra. I find textbooks written for theoretical physicists much gentler read. Physics textbooks can be a good place to start learning, say, differential geometry even if you don't care about physics (I don't).
- cyrusmith 8y agoRecommending Griffith to study quantum mechanics is just plain wrong. It's inconsistent, have many gaps in the material. There's a book superior in many regards to Griffith - the "Quantum Mechanics: Concepts and Applications" by Zettili.
- BeetleB 8y agoWhile I didn't like her saying that Griffith's is the book, in my experience, there is no the book for QM. Griffiths is good, but should be supplemented with another.
- projectileboy 8y agoOn the other hand, all of Griffith's works are very approachable - he's a gifted writer, and he seems to have an incredible knack for helping you find the core idea in something. I think all of his books should be the first word on their respective subjects - but not the last word.
- Koshkin 8y agoThere's an astonishingly large number of books on basic QM (only, perhaps, comparable to the number of books about differential forms :). It is probably because each author feels that something is missing or unclear or outdated in all other books. And this is despite the fact that QM in its fundamental shape has been complete since mid-1920s.
- ArtWomb 8y agoCaught this video the other day on Youtube. It's a archival 1959 lecture from MIT demonstrating light's wave particle duality. Using only a visible light source, photo-multiplier, and oscilloscope. Just remarkably clear and simple. It's amazing how much more the memory retains with a demo. And I can't help but think quantum computing could be made accessible to a wide audience in this way. The Physics of Light (1959) John King-MIT-Electromagnetic Radiation https://www.youtube.com/watch?v=bnSH6YDFXfk https://www.youtube.com/watch?v=bnSH6YDFXfk
- hintymad 8y agoTo put things in perspective, Susan is incredibly talented. She went from barely knowing high school math to enjoying advanced mathematical physics in fewer than three years, which means in this three years, she learned Analysis (not Steward Calculus, but at least Baby Rudin, mind you), Differential Equations, Linear Algebra, Abstract Algebra that covers at least groups, rings, and fields, Functional Analysis, Advanced Probability and Mathematic Statistics, Differential Geometry, to say the least. Besides that, she also needed to learn mechanics, E&M, Quantum Mechanics, and what not. She achieved all these in her part time as she was majored in Psychology. What's even more amazing is that she didn't find her latent talent until she went to college, and she could immediately enjoy Feynman's textbook with almost zero background in Physics! Bravo! Bravo!