From maximum force to physics in 9 lines – and implications for quantum gravity

Until 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.

I wonder what was the last fundamental scientific breakthrough made not by a member of academia...

I get your point, but consider this: I can not speak for OP but I have the same background as OP and I had the same reaction, even if I would try to phrase it more mellowly. I receive "crackpot" papers to my email multiple times a year. I generally try to engage with these "lone geniuses", because everyone deserves respect and not everyone has been lucky enough to be introduced to Physics in a structured way that would let them self-correct if they are making a *silly* mistake. I try very hard to not be patronizing when pointing out mistakes. I actually read the papers and try to do the best possible interpretation of crackpoty statements. I point to actual research question that are closest to the nonsensical metaphors used by the authors. I suggest reading materials. But in the vast majority of cases these authors do not care about doing the actual work to correct glaring mistakes, they just assume everyone else is wrong. So, it is quite reasonable to use the signals that OP detected in order to say that the paper is nonsense. That signal has been 100% correct for me for the last 9ish years, and I did spend the time to check exactly because I dislike the elitism of using this signal.

On one hand I agree with you. But on the other hand. Physics is not something you just teach yourself to such a high level. It would be completely unprecedented in modern times.

> author is not affiliated with any actual research institution.

I assume you’re probably upset, but this is elitist and an appeal to (elitist) authority. As someone who hopes to one day publish without affiliation, just point out why the paper is wrong rather than using appeals.

How about the first sentence in the body of the paper?

> In nature, all motion can be described by the principle of least action: motion minimizes action.

It is wrong. The actual principle is that the trajectories are stationary points of the action - not minima.

(Edit: It is wrong even with the "locality" caveat that the author later adds.)

That doesn't mean he's wrong.

The work must be evaluated on its own merit.

> 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.

Thanks 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/93...

It'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.

Maybe 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 )

Thanks, got it!