Other What are you reading now? (STEM only)

[vanhees71]

Again: that's how quantum mechanics describes it. But the whole EPR paper was, as I understand it, to say that entanglement shows that for a realist this is not an explanation.

But physical theories don't explain anything but "only" describe.

Again: nobody disputes the (as you call it) "locality of standard relativistic QFT" as one imposes in the quantization procedure of QFT (I'd call it "relativistic locality", because I doubt whether Einstein would be satisfied by it, but that's merely a guess).

Look, I'm not asking you to agree with me; I'm not even sure what to think of all this stuff myself. But I have a feeling that you miss the point of Norsen here (also because you claim the essence here is mathematics, not interpretations), and just labels it as his misunderstanding. But anyway, I don't need to defend other physicists here on issues I myself don't have a strong opinion about. I'm merely suggesting that you misread him, that's all.

Maybe than I don't understand Norsen right. I read his rattle against the standard view as saying that "relativistic locality" in fact must be violated, but that bluntly contradicts the mathematics of relativistic QFT. Of course, it's hard to understand vague philosophical ideas generally. So maybe Norsen doesn't say, what I understand him to say.

 

[Demystifier]

Maybe we should ask Norsen himself :P

Maybe someone could move this off topic discussion to another thread.

 

[Meow12]

 Something Deeply Hidden  by Sean Carroll. It's a non-mathematical intro to Quantum Mechanics.

 

[gentzen]

 Something Deeply Hidden  by Sean Carroll. It's a non-mathematical intro to Quantum Mechanics.

Well, its first part is "the best" introduction to the Many Worlds Interpretation (and Sean Carroll's perspective on it), and the second part is an introduction to Sean's own work on QFT and gravity emerging from QFT.

 

[haushofer]

But physical theories don't explain anything but "only" describe.

I agree with Demystifier that this is offtopic and should be relocated, but I'll just give one last reply, because I think this sentence is at the essence of the discussion: what's the difference between explaining and describing?

Physics does more than "only describing". "Only describing" is what a black box does: you get the right output, but you don't really understand what's under the hood. On top of that, in physics we use causal explanations. E.g., a pole of height 1 m casts a shadow on the ground of length 2,7 m. That follows from simple goniometry. But we don't read that equation "tangent of the angle is length of pole divided by length of shadow" always causally. E.g., we don't interpret this equation "length of shadow is length of pole divided by tan(20)" causally: it doesn't explain the length of the pole.

I guess people like Einstein considered the wavefunction in the EPR-experiment in a similar way: it's a useful calculational tool, but it doesn't give a causal explanation of why there is this perfect correlation between the particles.

Anyway, I'll leave it with this. I'd be happy to hear your thoughts in a separate topic at some later time. Which I would have opened myself if I had the time right now, but I'm busy finishing my next popular science book which is published this summer and needs my attention right now :P

 

[PhDeezNutz]

I just started

"Mathematics for Machine Learning" by Marc Peter Deisenroth, A. Aldo Faisal, Cheng Soon Ong

I look forward to demystifying all the complex machinery behind machine learning and understanding it from a mathematical point of view.

Personal Anecdote: After graduating with a masters in physics I had trouble breaking into tech/data science so I enrolled in one of those "Data Science Bootcamps". It was stupid so I quit, none of the mathematical details were divulged, just superficial banalities about "Bias vs. Variance trade-off" (which is a real thing but it's not like they actually explained it). I actually had to explain the concept of a partial derivative to one of the bootcamp instructors when doing "multilinear regression". I said "f this I'm out".

I feel like this book will help me actually grasp AI/ML on a level that isn't superficial/deluded/pretentious.

/soapbox

Also it's available for free by the Authors via Github if anyone is interested

https://mml-book.github.io/book/mml-book.pdf

 

[Jodo]

Presently reading The Trouble with Physics by Lee Smiling.

 

[Jodo]

Presently reading The Trouble with Physics by Lee Smiling.

Haha Smiling. Sorry Lee Smolin

 

[WWGD]

THAT, I can read!

There's one written by Isaac Walterson in a reverse universe.

 

[billtodd]

Information Theory by Cover.

 

[spiceagent11]

I was reading Shankar Quantum Mechanics but I had to take it back to the library.
Now I am browsing Whittaker, Analytical Dynamics, and also Torge, Geodesy.

 

[Hill]

Penrose's The Road to Reality. I am enjoying the contents a lot, but distracted by way too many typos, like this:

 

[martinbn]

Penrose's The Road to Reality. I am enjoying the contents a lot, but distracted by way too many typos, like this:

View attachment 340296

My speling is terrible, you have to tell me what the typos are.

 

[Hill]

My speling is terrible, you have to tell me what the typos are.

$gab$ instead of $g_{ab}$

 

[PhDeezNutz]

$gab$ instead of $g_{ab}$

I was tempted to say you are quibbling but I don’t think you are. Lower vs upper indices are important to distinguish and if it’s all in one line it’s ambiguous.

 

[martinbn]

$gab$ instead of $g_{ab}$

That wasn't obvious to you and distracted you! I only saw it because i reread the sentence a few times looking for typos.

 

[spiceagent11]

$gab$ instead of ##g_{ab}##

it wasn't obvious to you and distracted you true

 

[haushofer]

Penrose's The Road to Reality. I am enjoying the contents a lot, but distracted by way too many typos, like this:

View attachment 340296

It's the metric of a theory which is invariant w.r.t. upper and lower indices :P

 

[Hill]

It's the metric of a theory which is invariant w.r.t. upper and lower indices :P

No, it's metric in a general (pseudo) Riemannian geometry.

 

[Hill]

Penrose's The Road to Reality. I am enjoying the contents a lot, but distracted by way too many typos, like this:

View attachment 340296

I suspect that most of the "typos" are not typos in the printed book, but rather result of bad conversion of the book to Kindle version. Here is another of many examples:

I don't think there supposed to be empty boxes.

 

[Frimus]

I suspect that most of the "typos" are not typos in the printed book, but rather result of bad conversion of the book to Kindle version. Here is another of many examples:

View attachment 340405
I don't think there supposed to be empty boxes.

I'm definitely done with buying math and physics books for kindle. In most cases, it's a useless scumbag. I don't understand why Amazon didn't stop doing this a long time ago.

 

[Hill]

I'm definitely done with buying math and physics books for kindle. In most cases, it's a useless scumbag. I don't understand why Amazon didn't stop doing this a long time ago.

My experience differs. I am glad they didn't stop, for many reasons.

 

[Florian Geyer]

Sears and Zemansky's university physics 14e... it seems I am the only David here between so many Goliaths *_*
BTW it seems I will take a lot of time studying it.

 

[haushofer]

No, it's metric in a general (pseudo) Riemannian geometry.

I know. I tried to make a joke and failed.

 

[martinbn]

I know. I tried to make a joke and failed.

No, no, we got it. It was a good one.

 

[Hill]

I know. I tried to make a joke and failed.

I see. Sorry.

 

[haushofer]

No hard feelings. My kids also never laugh about my science jokes. Maybe when they turn 4 this year.

 

[ateixeira]

A few books on my part:

1. Vector Calculus by P. C. Matthews
2. A Course of Modern Analysis by Whittaker, Watson and Moll
3. Mathematical Methods for Physics and Engineering by Riley, Hobson and Bence
4. Mathematical Methods for Physicists: a concise introduction by Tai L. Chow
5. Classical Mechanics by Tai L. Chow

I am studying 8 hours per day to prepare for my upcoming PhD program and this is the first block of study...

 

[ateixeira]

I suspect that most of the "typos" are not typos in the printed book, but rather result of bad conversion of the book to Kindle version. Here is another of many examples:

View attachment 340405
I don't think there supposed to be empty boxes.

What is the page of this part of the text and the first one that you provided. I have the first edition of the book (I have been away from physics for more than a decade so I don't know if they were any posterior editions and/or reprinting) so that I can check if these typos are there

 

[Hill]

What is the page of this part of the text and the first one that you provided. I have the first edition of the book (I have been away from physics for more than a decade so I don't know if they were any posterior editions and/or reprinting) so that I can check if these typos are there

The first one is on p. 320, near the end of chapter 14.7. The second, p.385, the last paragraph of chapter 17.1.
I doubt that page numbers in the Kindle and printed versions correspond.