8 ms·
From maximum force to physics in 9 lines – and implications for quantum gravity
- KK-more 4y agoArxiv has this new paper: little math, great fun.
- rerx 4y agoThe title of this submission is heavily editorialized.
- dang 4y agoChanged now. (Submitted title was "A summary of modern physics in one table") Submitters: "Please use the original title, unless it is misleading or linkbait; don't editorialize." https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- KK-more 4y agoThanks, got it!
- vmilner 4y agoYou can certainly see why Feynman loved the Principle of Least Action and Lagrangians so much.
- potiuper 4y agoLeast is not the same as stationary.
- dannymi 4y agoIt's not, but sloppy terms are common there. People who use the words "principle of least action" and "the principle of stationary action" usually mean the same thing.
- vmilner 4y agoMaybe so, but I was quoting Feynman: “When I was in high school, my physics teacher—whose name was Mr. Bader—called me down one day after physics class and said, ‘You look bored; I want to tell you something interesting.’ Then he told me something which I found absolutely fascinating, and have, since then, always found fascinating. Every time the subject comes up, I work on it. In fact, when I began to prepare this lecture I found myself making more analyses on the thing. Instead of worrying about the lecture, I got involved in a new problem. The subject is this—the principle of least action." - Richard Feynman ( https://www.feynmanlectures.caltech.edu/II_19.html )
- jfengel 4y agoThe Rauscher maximum force is new to me, and all I find in a quick Google is the same author here. Other things about this paper don't seem right to me. Is he over interpreting something, or am I missing it?
- jleahy 4y agoThe author is the author of ‘motion mountain’ and not exactly 100% in the mainstream. His introductory textbooks once bet heavily on the non-existence of the Higgs boson and his own (non standard model, and now disproven) theories.
- koheripbal 4y agoThat doesn't mean he's wrong. The work must be evaluated on its own merit.
- quantum_mcts 4y agoI'd bet that the author did try to publish that in a peer-reviewed journal. He just doesn't want to show the review he got.
- hamiltonians 4y agono review.desk reject.
- jleahy 4y agoI didn't say he was wrong (about this).
- aaaaaaaaaaab 4y agoI’m no physicist, but how does v <= c imply special relativity? Where is the Minkowski space coming from? How do you derive the Lorentz transformation?
- Enginerrrd 4y agoYou can probably get there with that if you also postulate homogeneity of the laws of physics since arbitrary boosts would have to agree. I'm more curious about how maximum force implies Einstein's field equations since, well they apply to spacetime inside of the event horizon of a blackhole as well and I have a hard time seeing how that could be realized at or near the singularity. And the only citations for that claim are other papers of this author.
- potiuper 4y agohttps://www.researchgate.net/publication/360505079_From_maximum_force_to_the_field_equations_of_general_relativity_-_and_implications https://www.researchgate.net/publication/360505079_From_maxi...
- alok-g 4y agoThis may help. https://en.wikipedia.org/wiki/Special_relativity#Relativity_without_the_second_postulate https://en.wikipedia.org/wiki/Special_relativity#Relativity_...
- alok-g 4y agoSounds super cool. Will read when time permits. This may be worth spending months on for me (along with the references and prerequisite mathematics). Any recommendations for learning the math needed to understand this paper? (I understand probability, differential/integral calculus, etc., but not gauge groups.) The paper cites references for looking into the relevant derivations. Am unsure what all math those would need. Thanks.
- Luc 4y agoAt first glance it gave me a crackpotty vibe. Another commenter here mentioned something along those lines too.
- Jabbles 4y agoYou are, of course, free to do what you wish with your time. But I have to ask, why does this random paper attract you? If you had interest in rigorous physics before now, what steps have you taken towards that? Your comment just seems far too eager to start a months-long journey to understand something you have seen on the internet. Or did I miss your sarcasm? If you are truly serious about learning physics, I suggest you start here: https://www.susanrigetti.com/physics https://www.susanrigetti.com/physics and see the HN discussions here: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&query=so%20you%20want%20to%20learn%20physics&sort=byPopularity&type=story https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...
- alok-g 4y agoThanks for an honest and detailed response. Appreciated. Firstly, I had sensed that the paper hasn't been peer-reviewed. I assume though that the references have been. The paper on the very least felt like a good reading tour guide for the references. Then, to answer your question: I am an engineer by profession with interest in sciences. Whatever the tough circumstances that have been and continue to be, I have not had the opportunity to pursue Physics like I would have liked to. I remember say half of engineering mathematics from the college days, however, my physics understanding is limited to that of a first-year college student of physics. I am known in my personal and professional circles (working at a FAANG) as one of the smartest person they know, the 'go to' person for any STEM question they have. I keep reading science as a hobby, mainly via Wikipedia these days as that gives information in smaller chunks than a text book. I have read the Feynman Lectures on Physics. Some books on my reading list include those from Max Born, Leonard Susskind (The Theoretical Minimum series), and one I recently found from a hobbyist Physicist, Dennis Morris [1]. The latter again seems like a random author, however, the first chapter itself from one of his books has given me interesting perspectives I never came across from elsewhere. Coming to Susan's list, I had come across that on HN before and appreciate it. I am however clueless currently about how long the suggested route would take to finish. My current sense is that it won't be less than a few years. Now am I expecting to learn it in lesser? Well, here's my point of view: * I am interested only in the current understanding of Physics, worked starting from the laws as understood today. Sort of like what Principia Mathematica was intended to be. (I do maintain interest beyond that too, but am afraid life won't give me opportunity for more.) * Looking for something that does not lead to recursion over references. (It' likely that even the OP paper would lead like that.) This is the most challenging part with STEM literature today. * Something that actually says it. Many authors start using equations without even defining the variables, labeling the axes, thus leaving things unsaid. Many of them leave so much ambiguity in some of their sentences that I am unable to figure which one of the N different meanings fitting the same sentence is implied. (If they don't specify what the variable 'u' is for, then it could refer to any of the several physical quantities involved in the set up.) Here's another great book I found: The Road to Reality, Roger Penrose. I love the book. Have read seven chapters of it. It intended to be self-contained for what it covers (references are more for further reading). But then came the pain. It leaves so many (beautiful) open questions in mind, answers to which are important, but which are not answered in the book. And no amount of Google searches have led me to them. In that sense, it fails my criteria number three above. Now, here's the final thing I would like to share: I was once looking for a treatment of Automated Theorem Proving. I tried a book by a reputed author who himself had made contributions to the field. I don't recall the name. It was pitiful, the sentences were again more ambiguous than the author realized. Half-baked (incompletely-specified) definitions put to use frequently. I later found a concise paper by David Plaisted. Eight pages total, but covered everything that the book failed to. Everything was crisp and clear. I have more such experiences, and concluded that one author to another can be orders of magnitude difference. Reading all that, I'll sincerely appreciate if you/someone can guide me further. Specifically: How long Susan's suggested route is. I am a fairly smart person. If those criteria I set above are met, I'll be able to follow the material. Would the books I already have on my reading list help me? (Why am I not reading and finding out, well, I will. The circumstances my life are .. Long story.) Can reading the references in this OP paper be helpful? Thanks. [1] https://www.amazon.com/Quantum-Mechanics-Dennis-Morris/dp/9384007447/ https://www.amazon.com/Quantum-Mechanics-Dennis-Morris/dp/93...
- yostrovs 4y agoIf the nine lines were dashes, they would be able to be solidified through military means.
- quantum_mcts 4y agoAm physicist. First of all - this paper was never peer-reviewed. (And I suspect will never be.) The "summary table" looks weird and all over the place: both in levels of abstraction and in cause-effect relationships. The rest of the contents of the paper reek of "non-mainstream unrecognised genius" stuff. PS. Oh, and author is not affiliated with any actual research institution.
- aeonik 4y agoSounds to me like you just peer-reviewed it! We all appreciate your contribution to science.
- koheripbal 4y ago> this paper was never peer-reviewed. (And I suspect will never be.) ... > author is not affiliated with any actual research institution. There's something very elitist about this thinking. As if only members of academia are allowed to make breakthroughs.
- Espressosaurus 4y agoUntil it has been checked for errors and results verified to a suitable level of confidence, it's scribbling on a page. That's how science as a process works once you get beyond one person.
- GordonS 4y agoI think the GP's comment was more about the latter part of the quote, about the author not being affiliated with a research institution.
- quantum_mcts 4y agoI wonder what was the last fundamental scientific breakthrough made not by a member of academia...
- krastanov 4y ago
- quickthrower2 4y agoCode golf for physics?
- choxi 4y agoAre the claims about the shortest distance, maximum force, and shortest instant of time all undisputed? Makes the universe seem really discrete and simulation-y.
- krastanov 4y agoThey are a bit misrepresented. Think of most of them as "we know today's theory of physics breaks beyond these parameter regimes". There is no "minimal distance", rather there is "distance at which our math model does not work". No need to assume that things go discrete at that distance. There are some that are in a different style though: v<c is a fundamental postulate (stated in a very cluncky way).
- bmacho 4y ago> There is no "minimal distance", rather there is "distance at which our math model does not work". The paper is talking about an other type of minimum distance: minimum measurable distance. It predicts it to be 2*planck time (pg.7): Combining the experimental limits on speed v, force F and action W using the general relation for energy E = F vt = W/t leads to a limit on measurements of time t given by t ≥ √4G~/c5. (10) The five principles thus eliminate instants of time and introduce a minimum time interval, given by √4G~/c5 ≈ 1.1 · 10−43 s, twice the Planck time.
- meroes 4y agoI think not for distance and time. I’m not a physicist but Nima Arkani-Hamed phrases the minimal distance measurable as a physical process limited by QM and GR effects. To probe smaller and smaller distances one needs more and more energy, and past some minimum distance the energy becomes so great your experiment collapses into a black hole. That’s just what QM (small wavelength->high energy) and GR (force of gravity compared to the other forces, enough energy and gravity dominates) tell us. Since energy is related to time by a symmetry I think minimal time is implicated in the same way. A better interpretation than minimal discrete values of the universe is we are butting up against experimental limitations. An old concept that doesn’t necessarily mean the world is limited in the same we way are.
- meltyness 4y ago
- tagrun 4y agoPhysicist here. Why is this crackpot paper on the front page of HN? (I'm guessing posted by the crackpot author himself) No, you can't reconstruct physics from those 9 half-wrong statements that were pull out of thin air: entropy can very well be 0 (example: any microscopic system with 1 possible configuration, or any pure quantum state has 0 entropy), the minimum of action can be any number since the Lagrangian can be shifted by an arbitrary constant without changing the physics (and no you can't derive quantum mechanics or restrict possible Lagrangians just from the existence of \hbar), it is not possible to obtain the standard model Lagrangian just from the group structure U(1), SU(2), SU(3) and the number of particles and various constants, and the whole thing about maximum force (of which 1/3 of references are devoted) is a classical statement and is likely to be wrong in a quantum version of gravity. The rest appears to be random ramblings based on these 9 statements using middle school math. For non-physicists, this is not how physics papers look like (ie, mishmash of random statements pulled out of thin air with a sprinkle of real physics, followed by middle school math, and then wilder claims with additional assumptions out of thin air). Please try reading an actual physics paper from an open-access journal, for example PRX Quantum https://journals.aps.org/prxquantum/ https://journals.aps.org/prxquantum/ might be somewhat relevant to HN audience since there are a lot of papers connected to quantum computing
- quantum_mcts 4y agoBy the way, the symmetry breaking is U(1)*SU(2) -> U(1). Originally, U(1) is hypercharge generated. And electromagnetic U(1) appears after the electroweak symmetry breaking. So that one is wrong too. Also, how in Earth did he count 18 particles?