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A 9-line summary of textbook physics

motionmountain.net

41–50 of 179 posts

Re: A 9-line summary of textbook physics

#41
I've read a few times that you can derive the Maxwell equations from knowing that U(1) exists, as this article implies, that every point in space has (among other things) the symmetry of a circle.

But I've never seen this derivation. I assume it's either trivial or too complicated. Anyone has a link or thoughts on this?

Re: A 9-line summary of textbook physics

#43

Earlier quoted context omitted.

> Do not use a marker, a pen or a pencil to highlight or underline text on paper. It is a waste of time, provides false comfort and makes the text unreadable. What a load of elitist BS (pardon my French). When I was at University we were trained early on to cut the notion of a book being sacred. We should mark, note, create meaning on the pages with pens. I would not have been able to learn as much in my life if I ha…

Writing notes and comments is great - the text only says highlight or underline!

Even highlighting and marking is essential to help identify the core ideas on a page.

Re: A 9-line summary of textbook physics

#44
post #28

I opened a volume of the books linked in the page, and found this: « Learning allows us to discover what kind of person we can be. Learning widens knowledge, improves intelligence and provides a sense of achievement. Therefore, learning from a book, especially one about nature, should be efficient and enjoyable. Avoid bad learning methods like the plague! Do not use a marker, a pen or a pencil to highlight or underli…

I like it. The author is being real. This is what he sincerely thinks. You don't have to agree with everything an author says. I for one appreciate the candor. It's also a proven fact that many smartphone applications are effectively dispensers of dopamine at regular intervals. People check their social media like smokers take a smoke break. The author is right...albeit a bit terse and dramatic.

Author says "In particular, never, ever, learn from the internet", but then author makes a website teaching things. Hmm

Re: A 9-line summary of textbook physics

#45

Fun fact: all physics experiments ever made can be described by 9 lines, without any deviation between theory and observations. The 9 lines are sufficient to describe quantum physics and gravity. It seems that the 9 lines even contain all (update: natural) sciences, not only physics. Finding an exception to the 9 lines will make you famous. So will the discovery of a 10th line. Thousands of researchers work towards t…

This is just straight wrong. There is no computer in the world that can predict the outcome of, say, a drug trial from these equations. If your “science” requires an impossible computer to work then it’s not science it’s faith.

An impossible computer is different from a computer that humankind can not yet build. If our universe is a simulation, then some entity has already proven you wrong. If our universe isn't a simulation, our limited resources prevent us from running (detailed) universe-scale simulations. I'd say that we will eventually be able to simulate a drug interaction from these rules (it's the interaction between these rules that's the key) but I won't predict WHEN that might occur.

Re: A 9-line summary of textbook physics

#46
post #35

Why do the first chapters of all physics textbook ONLY talk about Greek philosophers and scientists and NEVER talk about contribution to Science from eastern civilization like India and China ? These civilizations have a very rich heritage and astounding contribution to many underlying scientific philosophies. Yet generation after generation of writers ignore them and it is sad to see that being true even today. It i…

Off the top of my head, I can name three things from either China or India that are science-related: the positional numbering system (and zero), the Chinese remainder theorem, and gunpowder. What am I missing that's very important yet rarely mentioned?

Re: A 9-line summary of textbook physics

#47
post #35

Why do the first chapters of all physics textbook ONLY talk about Greek philosophers and scientists and NEVER talk about contribution to Science from eastern civilization like India and China ? These civilizations have a very rich heritage and astounding contribution to many underlying scientific philosophies. Yet generation after generation of writers ignore them and it is sad to see that being true even today. It i…

The Indian number system is treated in detail. Indian mathematicians are mentioned and cited.

Re: A 9-line summary of textbook physics

#49
s/nature/the simulation/g

1. Total compute capacity is limited and redistributes toward areas of high activity.

2. Processor speed is limited.

3. Mutations are sensibly constrained to prevent overflow.

4. Smallest addressable memory space.

5. No process is ever fully idle.

6. IPC is done using circles.

7. The kernel however operates at the level of spheres, and pointers to pointers to pointers to spheres.

8. There's roughly 18 niceness levels, but rumors are there are a couple more.

9. About 25 programmers worked on the project and at the end each one got to pick a nothing-up-my-sleeve number. Some say there are Easter eggs hidden there yet to be discovered.

Re: A 9-line summary of textbook physics

#50
post #44
post #28

Earlier quoted context omitted.

I like it. The author is being real. This is what he sincerely thinks. You don't have to agree with everything an author says. I for one appreciate the candor. It's also a proven fact that many smartphone applications are effectively dispensers of dopamine at regular intervals. People check their social media like smokers take a smoke break. The author is right...albeit a bit terse and dramatic.

Author says "In particular, never, ever, learn from the internet", but then author makes a website teaching things. Hmm

The site is an advertisement for his books.

I think he's just old fashioned and believes learning from physical paper books is superior. He even has a link at the bottom of his site that says "Paper book lovers."

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