5 ms·

No bullshit guide to math and physics

189 points by ivan_ah 12y ago

Brakenshire 12y ago
It looks like 'no bullshit' in the sense of a heavily compressed primer using a lot of notation. I think that is very useful if you're in the right frame of mind. i.e. if you're happy with notation, and you want to refresh, or pick up something just directly from the undiluted concepts. Say, if you haven't looked at linear algebra for 5 years but suddenly need to use it for something, a text like this is going to be great. Or maybe as almost a syllabus/framework for connecting together concepts while you're doing a course. But I'm not sure it justifies the level of branding/rhetoric on the webpage. If you think mathematics is hard, an introduction to a linear algebra section which starts like this isn't going to change your mind: > Linear algebra is the math of vectors and matrices. Let n be a positive integer and let R denote the set of real numbers, then R^n is the set of all n-tuples of real numbers. A vector v E R^n is an n-tuple of real numbers. The notation “E” is read “element of S”...
- ivan_ah 12y ago
  Lol... in a previous version of the tutorial, I was using informal language to define vectors as "arrays of numbers," which attracted a lot of negative comments on HN because it wasn't mathematically precise enough. Note the LA book is "Tome II" in the series, and assumes you've read the "Tome I" (no BS guide to math & phys), which means the reader would be equipped to understand more formal math descriptions. But yeah... try giving an explanation for what a vector is that is both: (1) understandable and (2) mathematically precise.
  - Retra 12y ago
    "A vector is a composite quantity that has a magnitude and a direction. If something has a direction component and/or a magnitude component, it can be represented by a vector, and if something is a vector, we can ask for its direction or its magnitude (or both.)"
    - ivan_ah 12y ago
      Cool. That works well, if a bit geometrical. I'm going to think about rewording the intro in this way. However, I'd still have to introduce the notion of "coordinate vector" somehow, which begs for the word "tuple" or array, neither of which the right choice.
      - Retra 12y ago
        What I've described is the concept of a vector. You will have to determine the notation, and in setting the notation, and ordered list of basis vector coefficients is most commonly called a tuple, which is a generalization of ordered pair / triple / quadruple, etc.. (Though 'tuple' doesn't usually imply ordered.) The reason 'array' doesn't really work is that arrays are generally understood to be homogeneous in type, while tuples are usually Cartesian products. So if you are using a Cartesian coordinate system, tuple is the ideal term. http://en.wikipedia.org/wiki/Tuple#Type_theory http://en.wikipedia.org/wiki/Tuple#Type_theory
  - Brakenshire 12y ago
    Sorry if it came off a bit harsh. I think the emphasis I would put on all this is variety. All of these books are like different shapes and sizes of tools that you're using to pry open an understanding of the subject. At certain moments you'll want one sort of tool, and at different moments you'll want another. Maybe, on a particular topic, you want to read a chatty, informal explanation, and then you'll want something heavily summarized to nail things in place. Then you might want something really rigorous if you need to go into a lot of detail. Or it might be useful to have a text that scatters explanation of the concepts in amongst the steps to solve practical examples. All of these approaches have value. When I was learning Maths and Physics one of the major conclusions was that there was not enough variety in the material which was available, so when you hit a brick wall, part of the skill was developing an acceptance that you would hit your head against the wall repeatedly until something sank in. Which is inherently frustrating. FWIW I think it's also inevitable that a higher level summary has some kind of slightly leaky abstractions in order to give people a feel for what's going on. I don't see why Maths is any different from Chemistry, or other sciences, in the sense that you need to teach it progressively, at least to some degree. You talk first to a Chemistry student about covalent and ionic bonds, you don't start immediately on Quantum Mechanics and Orbital Theory.
  - RogerL 12y ago
    Try something like "you can think of a vector as an array of numbers. More precisely, [formal definition here]'. If you give somebody an analogy it gives them something to 'hang their thoughts on', if you know what I mean; you read the formalism and try to correlate it back to the analogy. Of course,an analogy is not an equivalence, so there will necessarily be exceptions. You can follow that up with something like "be careful not to assume X from the array of numbers idea; the formal defition states Y, which precludes that". Well, you get the idea.
JTon 12y ago
FYI at the very bottom of the link there is a free stuff section where you can sample the work from the book.
- ivan_ah 12y ago
  That's right. The 'sympy_tutorial.pdf' in corresponds to Appendix D in the book, and the mechanics tutorial corresponds to Chapter 2. BTW, here's a link to a PDF version of the book preview http://minireference.com/static/excerpts/noBSguide_v5_preview.pdf http://minireference.com/static/excerpts/noBSguide_v5_previe... (137pp, 6MB) in case flipping through low resolution .jpgs isn't your thing ;)
  - deleted 12y ago
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thesimon 12y ago
It is probably a great idea, but looking at the sample it looks like just another textbook that is hard and complex: http://cl.ly/image/150V0z3T2b0g http://cl.ly/image/150V0z3T2b0g In contrast to that, I found https://openstaxcollege.org/books https://openstaxcollege.org/books a really awesome resource for learning physics (on an easy level) Edit: Cutting out all the "bullshit" seems to make it hard for a "busy adult" to easily learn the concept, but it actually seems like a good resource to improve your knowledge which you simply forgot.
- FullyFunctional 12y ago
  For the part of noBS I'm through I appreciate the get-to-the-point explanation and amusing (thought highly opinionated) examples. I don't think there's much you can do better when you are teaching standard concepts and notation; it will always look foreign at first.
- whitewhim 12y ago
  Looking at the sample, I agree with you. Condensed ≠ easy to understand. Honestly, a lot of the graduate texts I deal with look easier to understand. In my opinion, every single concept should be introduced with physical analogies if one wishes a reader with no maturity in the subject to actually understand. Then again if the author is going for "no-bullshit" this could serve as a good reference for someone who just needs a quick easy to understand reference.
- whitewhim 12y ago
  Looking at the sample, I agree with you. Condensed ≠ easy to understand. Honestly, a lot of the graduate texts I deal with look easier to understand. In my opinion, every single concept should be introduced with physical analogies if one wishes a reader with no maturity in the subject to actually understand. Then again if the author is going for "no-bullshit" this could serve as a good reference for someone who just needs a quick easy to understand reference.
- muaddirac 12y ago
  To my eyes it's a quick overview of some linear algebra basics, the only complex thing possibly being notation (but I would assume and hope the book builds up to it while also building intuition).
jkot 12y ago
Hm, that guide has lot of bullshit. Who cares about 4 different forces? Just invent unified theory and compress it into single formula :-)
jplahn 12y ago
I'm definitely going to look into this. Even with working on a second degree in Engineering Mechanics, I've found that I have forgotten a considerable amount of information I learned earlier in my degree (likely replaced by the overwhelming information in CS). I would love to brush back up on those areas, if only to overcome my fears of mechanical inadequacy. Without constant application, material as complex as mechanics can simply slip away, so having a book like this that hits on the high notes would be fantastic.
- ErikRogneby 12y ago
  Khan Academy works for adults too. it goes all the way up through multi-variable calculus. I've been pretty impressed. https://www.khanacademy.org/math/multivariable-calculus https://www.khanacademy.org/math/multivariable-calculus
ErikRogneby 12y ago
Part of me hoped it would be written in the style of "Why's poignant guide to Ruby".
- jordigh 12y ago
  I think that's part of the alleged "bullshit", pretty stories that distract from the actual material. Then again, similar methods like in Learn You A Haskell For Great Good seem to work on me. I do wonder how much time I spend trying to understand the jokes and references.
devty 12y ago
How is this the top post in HN right now?
- ebbv 12y ago
  I'd suggest that if a book on maths and physics doesn't interest you, then it is you, not the book, which isn't a great fit for HN.
  - up_and_up 12y ago
    This is a repost: https://news.ycombinator.com/item?id=4994367 https://news.ycombinator.com/item?id=4994367
  - Steuard 12y ago
    Sure, but why this book? I mean, it seems like a nice review guide and all (though probably too terse for someone trying to learn the material for the first time), but what about it is catching peoples' attention? If I post about Tom Moore's fantastic "Six Ideas that Shaped Physics" textbook series (http://www.physics.pomona.edu/sixideas/ http://www.physics.pomona.edu/sixideas/), which is based on a career's worth of experience and many of the best ideas from the active field of Physics Education Research, is that also a front page link? (I'm teaching my Modern Physics course out of two of those volumes this semester, and the students seem to really like it.)
    - crimsonalucard 12y ago
      Just add "bullshit" to the title. "Six no bullshit ideas that shaped physics" Boom! front page.
    - ebbv 12y ago
      I'd wager anything you want to post about physics will probably get an enthusiastic response on here.
  - hnnewguy 12y ago
    >I'd suggest that if a book on maths and physics doesn't interest you It's a math textbook. There are thousands of them. What makes this one so special? The fact that it says, "No B.S."? It has a fancy webpage? It looks pretty standard, and isn't even very cheap.
wehadfun 12y ago
From the mechanics section: >To solve a mechanics problem is to obtain the equation of motion x(t) This is exactly the type of bullshit that confuses people. To a regular person what the fuck is x(t)?
- ebbv 12y ago
  This is not what he was referring to as bullshit. What he was calling bullshit is putting flowery stories around problems. E.g., "A train is traveling from Dusseldorf to Amsterdam..." x(t) is not bullshit just because you don't understand it. It's a mathematical function. x is the function, t is time. Meaning that you can give the function the time you're interested in and the function can tell you the motion of the object. I'd imagine the text goes on from there to explain how you obtain the function based on the sentence you quote. The website lists prerequisites to reading the book, perhaps you don't meet them?
  - wehadfun 12y ago
    thanks for the personal attack. From reading the website it seem like an HR person or fireman could read this book and understand mechanics which is bullshit. Even your explanation would confuse them "x is the function?", "What function does x serve?", "How the fuck would I give an 'x' the time?"
    - Retra 12y ago
      Reading and Thinking is still requirements. That's not the "bullshit" the author is trying to avoid.
JohnLen 12y ago
Will give a try on this book. Seems interesting
peter303 12y ago
If you need to use a guide, then it is B.S. No shortcuts to taking classes, doing practice problems, and tests. The main ting the modernworld offers is some nifty animations to illustrate these equations. We didnt have such in my day.
Garlef 12y ago
"Linear algebra is the math of vectors and matrices." "The matrix-vector product is used to define the notion of a linear transformation" This is BS. * First: Linear Algebra actually is the math of linear transformations. * Second: No sane mathematician would define linear transformations in terms of matrices. Vectors and matrices are only one way to model linear transformations; They help beginners to imagine linear algebra; But often, refraining from using coordinates delivers a much clearer picture. Maybe this should be called the "No BS guide to passing your engineering math tests".
- ivan_ah 12y ago
  I'm guessing you're reading the short tutorial, which starts off with some computational aspects of LA. As soon as I introduce linear transformations (a few sections later) I make an update to this statement turning it into "linear algebra is all about vectors and linear transformations."
  - Garlef 12y ago
    Yeah. I was only reading through the four pager.
- ams6110 12y ago
  If the language of "sane mathematicians" was comprehensible to most people, there would be no need for books like this.
- tjradcliffe 12y ago
  What "math" means to people outside of math--including physicists and engineers--is completely different from what "math" means to people inside math. We really ought to have a different word for the two fields. Even "applied math" doesn't cut it, because most applied mathematicians still think like mathematicians, and it ain't like the rest of us. What mathematicians don't see is that when they rail against the kind of concrete, heuristic definitions that non-mathematicians use for parts of mathematics, is that it isn't just that we don't care that there is a better, more general, more abstract, more justifiable definition out there, it's that we can't understand them so they aren't useful to us, even a little bit. You may as well try explaining Shakespeare to your dog: it'll frustrate you and annoy the dog, who is perfectly happy to use Shakespeare for his intended purpose, which is to say, chewing on the edges of the "Complete Shakespeare" for entertainment. That's an overstatement, but the gulf between the mathematician's mind-set and the mind-set of physicists and engineers is still far wider than most mathematicians appreciate, and it really would be valuable to have a different word for what physicists and engineers do when we "do math", because it is not "math" the way you mean it.
mirashii 12y ago
While, like most people here, anything that claims to disrupt the textbook industry gets me excited on instinct, even a cursory glance shows some major issues with this that leaves me questioning whether someone who hasn't taken these classes could do well. An example from the first chapter. > By the way, before we continue our discussion, let it be noted: the equality symbol (=) means that all that is to the left of = is equal to all that is to the right of =. To keep this equality statement true, for every change you apply to the left side of the equation, you must apply the same change to the right side of the equation. What is a change, and why do I have to do it to both sides? Is deleting all the exponents on both sides a valid change as long as I do it to both sides? What about dividing both sides by 0? This is a woefully inadequate explanation of manipulating equations. Maybe that's the bullshit that's been taken out, but I consider it fundamentals which often trip a person up later due to missing knowledge, and where I most commonly hear the phrase "Well you never told me I couldn't..." come out of a struggling student's mouth.
- ivan_ah 12y ago
  You make a good point, thought you're reading the "ice breaker" section which is meant to be very introductory. A few sections later I define "change on both sides" more formally as "applying a function".
  - mirashii 12y ago
    These sorts of fundamentals are glossed over or not mentioned throughout, though. For instance, both in and after the section on integration, the fact that \int (f+g) = \int f + \int g. No explanation or limitation is placed on that information. If I can do that, can't I also write \int (f/g) = \int f / \int g ? These are common tripping points for many.
    - blixt 12y ago
      I actually have this book but haven't read it yet. As someone who joined the web startup world when I was 14 and never went back to school, I need to work on my math skills. I believe strongly in building knowledge by layers (start with a simple overview, work you way towards the core of the subject) rather than going in for the detail right away. Would you say this book does the former well and just doesn't cover the details very well, or is the book somehow flawed?
crimsonalucard 12y ago
Everybody starts off writing a textbook thinking that it will disrupt the industry.
bkcooper 12y ago
The feeling I get from that page is: You've heard the expression "let's get busy"? Well this is a textbook that gets biz-zay. Consistently and thoroughly.
pitt1980 12y ago
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Keyframe 12y ago
Years (eons?) ago I bought something similar. Two book guide through math which I still find useful to this day: this: http://www.amazon.com/Mathematics-Physical-Sciences-Robert-Lambourne/dp/0471852074 http://www.amazon.com/Mathematics-Physical-Sciences-Robert-L... and this: http://www.amazon.com/Further-Mathematics-Physical-Sciences-Michael/dp/0471867233 http://www.amazon.com/Further-Mathematics-Physical-Sciences-...
cbsmith 12y ago
I'd love to see a table of contents, as it'd make it much easier to judge the breadth of the subject matter. One concern I have is I didn't see much that looked like discrete/finite math. That compounds the mistake made by too many math curriculums. In particular, statistics and probabilities rule our world these days (and seem destined to do so only more in the future), yet so many people never even get a basic education in them.
- ivan_ah 12y ago
  For TOC, see http://minireference.com/static/noBSguide_v5_TOC.pdf http://minireference.com/static/noBSguide_v5_TOC.pdf Note: the aim of the book is to cover mechanics (Physics 101) and calculus (I and II). There is a second tome in the works that will cover optics, waves, E&M, and vector calculus.
  - cbsmith 12y ago
    Ah, so this is focused on Physics. Can't look a gift horse in the mouth, but I'm not sure of the intended use case for such a guide. Normally you need a pretty formal foundation in Physics to get much value from it, which is why I hopped on the discrete math picture (lots of people do programming without any need for a formal math education).
mzaccari 12y ago
My mental muscle for math has definitely atrophied since graduating with an engineering degree. I’ve been looking for a nice way to exercise it, and this looks like something that can get me there. For a more in-depth discussion of physics, I’ve found the Feynman Lectures [1,2] to be quite enjoyable. It’s a long read (I’ve only finished the first book) but it is very thorough. [1] http://www.feynmanlectures.caltech.edu/ http://www.feynmanlectures.caltech.edu/ [2] http://www.amazon.com/Feynman-Lectures-Physics-boxed-set/dp/0465023827/ref=sr_1_3?s=books&ie=UTF8&qid=1427731116&sr=1-3&keywords=feynman http://www.amazon.com/Feynman-Lectures-Physics-boxed-set/dp/...
- Fenume 12y ago
  This [0] book is to mathematics what Feynman Lectures are to physics (debatable, but I think it's worth the read). [0] http://www.amazon.com/dp/0486409163/ http://www.amazon.com/dp/0486409163/ (Mathematics: Its Content, Methods and Meaning)
ayushgta 12y ago
Forks interested in this should also see http://betterexplained.com/ebook/math/ http://betterexplained.com/ebook/math/
esalman 12y ago
Which textbook/guide actually bullshits math and physics, may I ask?
- ivan_ah 12y ago
  I'd say the standard UGRAD-level physics and calculus textbooks (Serway, Giancoli, Stewart) are full of BS. Do you really need to read 1000+ pages to learn calculus? Textbooks after first-year university are normally much better and bullshitfree. Graduate textbooks are usually solid. Also, there are many free textbooks out there that are essentially bullshit free, e.g. Calculus Made Easy by Silvanus P. Thompson available at http://www.gutenberg.org/ebooks/33283 http://www.gutenberg.org/ebooks/33283
  - giardini 12y ago
    ivan_ah says: "... Textbooks after first-year university are normally much better and bullshitfree. Graduate textbooks are usually solid." Amen! To that end I recommend "Mathematics Of Physics And Modern Engineering - Second Edition by I. S. Sokolnikoff and R. M. Redheffer http://www.amazon.com/Mathematics-Physics-Engineering-Stephen-Sokolnikoff/dp/0070596255/ref=sr_1_2?s=books&ie=UTF8&qid=1427734261&sr=1-2&keywords=mathematics+of+physics+and+modern+engineering+by+sokolnikoff#customerReviews http://www.amazon.com/Mathematics-Physics-Engineering-Stephe... Each chapter is independent, the text has a thorough index and covers most everything. Few errors, well-illustrated, nicely-sized and pleasant on the eyes. Most easy to read math book ever.
FrankenPC 12y ago
As an analog from the electronics field, look at the Forrest Mims notebook series. That is a superb example of how to take something insanely complex and converting it to no bullshit. The example I saw on the website looks like just another dry math textbook. I've seen high school math books with more color and engaging concepts than this.

189 points by ivan_ah 12y ago

It looks like 'no bullshit' in the sense of a heavily compressed primer using a lot of notation. I think that is very useful if you're in the right frame of mind. i.e. if you're happy with notation, and you want to refresh, or pick up something just directly from the undiluted concepts. Say, if you haven't looked at linear algebra for 5 years but suddenly need to use it for something, a text like this is going to be great. Or maybe as almost a syllabus/framework for connecting together concepts while you're doing a course. But I'm not sure it justifies the level of branding/rhetoric on the webpage. If you think mathematics is hard, an introduction to a linear algebra section which starts like this isn't going to change your mind: > Linear algebra is the math of vectors and matrices. Let n be a positive integer and let R denote the set of real numbers, then R^n is the set of all n-tuples of real numbers. A vector v E R^n is an n-tuple of real numbers. The notation “E” is read “element of S”...

ivan_ah 12y ago
Lol... in a previous version of the tutorial, I was using informal language to define vectors as "arrays of numbers," which attracted a lot of negative comments on HN because it wasn't mathematically precise enough. Note the LA book is "Tome II" in the series, and assumes you've read the "Tome I" (no BS guide to math & phys), which means the reader would be equipped to understand more formal math descriptions. But yeah... try giving an explanation for what a vector is that is both: (1) understandable and (2) mathematically precise.
- Retra 12y ago
  "A vector is a composite quantity that has a magnitude and a direction. If something has a direction component and/or a magnitude component, it can be represented by a vector, and if something is a vector, we can ask for its direction or its magnitude (or both.)"
  - ivan_ah 12y ago
    Cool. That works well, if a bit geometrical. I'm going to think about rewording the intro in this way. However, I'd still have to introduce the notion of "coordinate vector" somehow, which begs for the word "tuple" or array, neither of which the right choice.
    - Retra 12y ago
      What I've described is the concept of a vector. You will have to determine the notation, and in setting the notation, and ordered list of basis vector coefficients is most commonly called a tuple, which is a generalization of ordered pair / triple / quadruple, etc.. (Though 'tuple' doesn't usually imply ordered.) The reason 'array' doesn't really work is that arrays are generally understood to be homogeneous in type, while tuples are usually Cartesian products. So if you are using a Cartesian coordinate system, tuple is the ideal term. http://en.wikipedia.org/wiki/Tuple#Type_theory http://en.wikipedia.org/wiki/Tuple#Type_theory
- Brakenshire 12y ago
  Sorry if it came off a bit harsh. I think the emphasis I would put on all this is variety. All of these books are like different shapes and sizes of tools that you're using to pry open an understanding of the subject. At certain moments you'll want one sort of tool, and at different moments you'll want another. Maybe, on a particular topic, you want to read a chatty, informal explanation, and then you'll want something heavily summarized to nail things in place. Then you might want something really rigorous if you need to go into a lot of detail. Or it might be useful to have a text that scatters explanation of the concepts in amongst the steps to solve practical examples. All of these approaches have value. When I was learning Maths and Physics one of the major conclusions was that there was not enough variety in the material which was available, so when you hit a brick wall, part of the skill was developing an acceptance that you would hit your head against the wall repeatedly until something sank in. Which is inherently frustrating. FWIW I think it's also inevitable that a higher level summary has some kind of slightly leaky abstractions in order to give people a feel for what's going on. I don't see why Maths is any different from Chemistry, or other sciences, in the sense that you need to teach it progressively, at least to some degree. You talk first to a Chemistry student about covalent and ionic bonds, you don't start immediately on Quantum Mechanics and Orbital Theory.
- RogerL 12y ago
  Try something like "you can think of a vector as an array of numbers. More precisely, [formal definition here]'. If you give somebody an analogy it gives them something to 'hang their thoughts on', if you know what I mean; you read the formalism and try to correlate it back to the analogy. Of course,an analogy is not an equivalence, so there will necessarily be exceptions. You can follow that up with something like "be careful not to assume X from the array of numbers idea; the formal defition states Y, which precludes that". Well, you get the idea.

JTon 12y ago

FYI at the very bottom of the link there is a free stuff section where you can sample the work from the book.

ivan_ah 12y ago
That's right. The 'sympy_tutorial.pdf' in corresponds to Appendix D in the book, and the mechanics tutorial corresponds to Chapter 2. BTW, here's a link to a PDF version of the book preview http://minireference.com/static/excerpts/noBSguide_v5_preview.pdf http://minireference.com/static/excerpts/noBSguide_v5_previe... (137pp, 6MB) in case flipping through low resolution .jpgs isn't your thing ;)
- deleted 12y ago
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thesimon 12y ago

It is probably a great idea, but looking at the sample it looks like just another textbook that is hard and complex: http://cl.ly/image/150V0z3T2b0g http://cl.ly/image/150V0z3T2b0g In contrast to that, I found https://openstaxcollege.org/books https://openstaxcollege.org/books a really awesome resource for learning physics (on an easy level) Edit: Cutting out all the "bullshit" seems to make it hard for a "busy adult" to easily learn the concept, but it actually seems like a good resource to improve your knowledge which you simply forgot.

FullyFunctional 12y ago
For the part of noBS I'm through I appreciate the get-to-the-point explanation and amusing (thought highly opinionated) examples. I don't think there's much you can do better when you are teaching standard concepts and notation; it will always look foreign at first.
whitewhim 12y ago
Looking at the sample, I agree with you. Condensed ≠ easy to understand. Honestly, a lot of the graduate texts I deal with look easier to understand. In my opinion, every single concept should be introduced with physical analogies if one wishes a reader with no maturity in the subject to actually understand. Then again if the author is going for "no-bullshit" this could serve as a good reference for someone who just needs a quick easy to understand reference.
whitewhim 12y ago
Looking at the sample, I agree with you. Condensed ≠ easy to understand. Honestly, a lot of the graduate texts I deal with look easier to understand. In my opinion, every single concept should be introduced with physical analogies if one wishes a reader with no maturity in the subject to actually understand. Then again if the author is going for "no-bullshit" this could serve as a good reference for someone who just needs a quick easy to understand reference.
muaddirac 12y ago
To my eyes it's a quick overview of some linear algebra basics, the only complex thing possibly being notation (but I would assume and hope the book builds up to it while also building intuition).

jkot 12y ago

Hm, that guide has lot of bullshit. Who cares about 4 different forces? Just invent unified theory and compress it into single formula :-)

jplahn 12y ago

I'm definitely going to look into this. Even with working on a second degree in Engineering Mechanics, I've found that I have forgotten a considerable amount of information I learned earlier in my degree (likely replaced by the overwhelming information in CS). I would love to brush back up on those areas, if only to overcome my fears of mechanical inadequacy. Without constant application, material as complex as mechanics can simply slip away, so having a book like this that hits on the high notes would be fantastic.

ErikRogneby 12y ago
Khan Academy works for adults too. it goes all the way up through multi-variable calculus. I've been pretty impressed. https://www.khanacademy.org/math/multivariable-calculus https://www.khanacademy.org/math/multivariable-calculus

ErikRogneby 12y ago

Part of me hoped it would be written in the style of "Why's poignant guide to Ruby".

jordigh 12y ago
I think that's part of the alleged "bullshit", pretty stories that distract from the actual material. Then again, similar methods like in Learn You A Haskell For Great Good seem to work on me. I do wonder how much time I spend trying to understand the jokes and references.

devty 12y ago

How is this the top post in HN right now?

ebbv 12y ago
I'd suggest that if a book on maths and physics doesn't interest you, then it is you, not the book, which isn't a great fit for HN.
- up_and_up 12y ago
  This is a repost: https://news.ycombinator.com/item?id=4994367 https://news.ycombinator.com/item?id=4994367
- Steuard 12y ago
  Sure, but why this book? I mean, it seems like a nice review guide and all (though probably too terse for someone trying to learn the material for the first time), but what about it is catching peoples' attention? If I post about Tom Moore's fantastic "Six Ideas that Shaped Physics" textbook series (http://www.physics.pomona.edu/sixideas/ http://www.physics.pomona.edu/sixideas/), which is based on a career's worth of experience and many of the best ideas from the active field of Physics Education Research, is that also a front page link? (I'm teaching my Modern Physics course out of two of those volumes this semester, and the students seem to really like it.)
  - crimsonalucard 12y ago
    Just add "bullshit" to the title. "Six no bullshit ideas that shaped physics" Boom! front page.
  - ebbv 12y ago
    I'd wager anything you want to post about physics will probably get an enthusiastic response on here.
- hnnewguy 12y ago
  >I'd suggest that if a book on maths and physics doesn't interest you It's a math textbook. There are thousands of them. What makes this one so special? The fact that it says, "No B.S."? It has a fancy webpage? It looks pretty standard, and isn't even very cheap.

wehadfun 12y ago

From the mechanics section: >To solve a mechanics problem is to obtain the equation of motion x(t) This is exactly the type of bullshit that confuses people. To a regular person what the fuck is x(t)?

ebbv 12y ago
This is not what he was referring to as bullshit. What he was calling bullshit is putting flowery stories around problems. E.g., "A train is traveling from Dusseldorf to Amsterdam..." x(t) is not bullshit just because you don't understand it. It's a mathematical function. x is the function, t is time. Meaning that you can give the function the time you're interested in and the function can tell you the motion of the object. I'd imagine the text goes on from there to explain how you obtain the function based on the sentence you quote. The website lists prerequisites to reading the book, perhaps you don't meet them?
- wehadfun 12y ago
  thanks for the personal attack. From reading the website it seem like an HR person or fireman could read this book and understand mechanics which is bullshit. Even your explanation would confuse them "x is the function?", "What function does x serve?", "How the fuck would I give an 'x' the time?"
  - Retra 12y ago
    Reading and Thinking is still requirements. That's not the "bullshit" the author is trying to avoid.

JohnLen 12y ago

Will give a try on this book. Seems interesting

peter303 12y ago

If you need to use a guide, then it is B.S. No shortcuts to taking classes, doing practice problems, and tests. The main ting the modernworld offers is some nifty animations to illustrate these equations. We didnt have such in my day.

Garlef 12y ago

"Linear algebra is the math of vectors and matrices." "The matrix-vector product is used to define the notion of a linear transformation" This is BS. * First: Linear Algebra actually is the math of linear transformations. * Second: No sane mathematician would define linear transformations in terms of matrices. Vectors and matrices are only one way to model linear transformations; They help beginners to imagine linear algebra; But often, refraining from using coordinates delivers a much clearer picture. Maybe this should be called the "No BS guide to passing your engineering math tests".

ivan_ah 12y ago
I'm guessing you're reading the short tutorial, which starts off with some computational aspects of LA. As soon as I introduce linear transformations (a few sections later) I make an update to this statement turning it into "linear algebra is all about vectors and linear transformations."
- Garlef 12y ago
  Yeah. I was only reading through the four pager.
ams6110 12y ago
If the language of "sane mathematicians" was comprehensible to most people, there would be no need for books like this.
tjradcliffe 12y ago
What "math" means to people outside of math--including physicists and engineers--is completely different from what "math" means to people inside math. We really ought to have a different word for the two fields. Even "applied math" doesn't cut it, because most applied mathematicians still think like mathematicians, and it ain't like the rest of us. What mathematicians don't see is that when they rail against the kind of concrete, heuristic definitions that non-mathematicians use for parts of mathematics, is that it isn't just that we don't care that there is a better, more general, more abstract, more justifiable definition out there, it's that we can't understand them so they aren't useful to us, even a little bit. You may as well try explaining Shakespeare to your dog: it'll frustrate you and annoy the dog, who is perfectly happy to use Shakespeare for his intended purpose, which is to say, chewing on the edges of the "Complete Shakespeare" for entertainment. That's an overstatement, but the gulf between the mathematician's mind-set and the mind-set of physicists and engineers is still far wider than most mathematicians appreciate, and it really would be valuable to have a different word for what physicists and engineers do when we "do math", because it is not "math" the way you mean it.

mirashii 12y ago

While, like most people here, anything that claims to disrupt the textbook industry gets me excited on instinct, even a cursory glance shows some major issues with this that leaves me questioning whether someone who hasn't taken these classes could do well. An example from the first chapter. > By the way, before we continue our discussion, let it be noted: the equality symbol (=) means that all that is to the left of = is equal to all that is to the right of =. To keep this equality statement true, for every change you apply to the left side of the equation, you must apply the same change to the right side of the equation. What is a change, and why do I have to do it to both sides? Is deleting all the exponents on both sides a valid change as long as I do it to both sides? What about dividing both sides by 0? This is a woefully inadequate explanation of manipulating equations. Maybe that's the bullshit that's been taken out, but I consider it fundamentals which often trip a person up later due to missing knowledge, and where I most commonly hear the phrase "Well you never told me I couldn't..." come out of a struggling student's mouth.

ivan_ah 12y ago
You make a good point, thought you're reading the "ice breaker" section which is meant to be very introductory. A few sections later I define "change on both sides" more formally as "applying a function".
- mirashii 12y ago
  These sorts of fundamentals are glossed over or not mentioned throughout, though. For instance, both in and after the section on integration, the fact that \int (f+g) = \int f + \int g. No explanation or limitation is placed on that information. If I can do that, can't I also write \int (f/g) = \int f / \int g ? These are common tripping points for many.
  - blixt 12y ago
    I actually have this book but haven't read it yet. As someone who joined the web startup world when I was 14 and never went back to school, I need to work on my math skills. I believe strongly in building knowledge by layers (start with a simple overview, work you way towards the core of the subject) rather than going in for the detail right away. Would you say this book does the former well and just doesn't cover the details very well, or is the book somehow flawed?

crimsonalucard 12y ago

Everybody starts off writing a textbook thinking that it will disrupt the industry.

bkcooper 12y ago

The feeling I get from that page is: You've heard the expression "let's get busy"? Well this is a textbook that gets biz-zay. Consistently and thoroughly.

pitt1980 12y ago

Keyframe 12y ago

Years (eons?) ago I bought something similar. Two book guide through math which I still find useful to this day: this: http://www.amazon.com/Mathematics-Physical-Sciences-Robert-Lambourne/dp/0471852074 http://www.amazon.com/Mathematics-Physical-Sciences-Robert-L... and this: http://www.amazon.com/Further-Mathematics-Physical-Sciences-Michael/dp/0471867233 http://www.amazon.com/Further-Mathematics-Physical-Sciences-...

cbsmith 12y ago

I'd love to see a table of contents, as it'd make it much easier to judge the breadth of the subject matter. One concern I have is I didn't see much that looked like discrete/finite math. That compounds the mistake made by too many math curriculums. In particular, statistics and probabilities rule our world these days (and seem destined to do so only more in the future), yet so many people never even get a basic education in them.

ivan_ah 12y ago
For TOC, see http://minireference.com/static/noBSguide_v5_TOC.pdf http://minireference.com/static/noBSguide_v5_TOC.pdf Note: the aim of the book is to cover mechanics (Physics 101) and calculus (I and II). There is a second tome in the works that will cover optics, waves, E&M, and vector calculus.
- cbsmith 12y ago
  Ah, so this is focused on Physics. Can't look a gift horse in the mouth, but I'm not sure of the intended use case for such a guide. Normally you need a pretty formal foundation in Physics to get much value from it, which is why I hopped on the discrete math picture (lots of people do programming without any need for a formal math education).

mzaccari 12y ago

My mental muscle for math has definitely atrophied since graduating with an engineering degree. I’ve been looking for a nice way to exercise it, and this looks like something that can get me there. For a more in-depth discussion of physics, I’ve found the Feynman Lectures [1,2] to be quite enjoyable. It’s a long read (I’ve only finished the first book) but it is very thorough. [1] http://www.feynmanlectures.caltech.edu/ http://www.feynmanlectures.caltech.edu/ [2] http://www.amazon.com/Feynman-Lectures-Physics-boxed-set/dp/0465023827/ref=sr_1_3?s=books&ie=UTF8&qid=1427731116&sr=1-3&keywords=feynman http://www.amazon.com/Feynman-Lectures-Physics-boxed-set/dp/...

Fenume 12y ago
This [0] book is to mathematics what Feynman Lectures are to physics (debatable, but I think it's worth the read). [0] http://www.amazon.com/dp/0486409163/ http://www.amazon.com/dp/0486409163/ (Mathematics: Its Content, Methods and Meaning)

ayushgta 12y ago

Forks interested in this should also see http://betterexplained.com/ebook/math/ http://betterexplained.com/ebook/math/

esalman 12y ago

Which textbook/guide actually bullshits math and physics, may I ask?

ivan_ah 12y ago
I'd say the standard UGRAD-level physics and calculus textbooks (Serway, Giancoli, Stewart) are full of BS. Do you really need to read 1000+ pages to learn calculus? Textbooks after first-year university are normally much better and bullshitfree. Graduate textbooks are usually solid. Also, there are many free textbooks out there that are essentially bullshit free, e.g. Calculus Made Easy by Silvanus P. Thompson available at http://www.gutenberg.org/ebooks/33283 http://www.gutenberg.org/ebooks/33283
- giardini 12y ago
  ivan_ah says: "... Textbooks after first-year university are normally much better and bullshitfree. Graduate textbooks are usually solid." Amen! To that end I recommend "Mathematics Of Physics And Modern Engineering - Second Edition by I. S. Sokolnikoff and R. M. Redheffer http://www.amazon.com/Mathematics-Physics-Engineering-Stephen-Sokolnikoff/dp/0070596255/ref=sr_1_2?s=books&ie=UTF8&qid=1427734261&sr=1-2&keywords=mathematics+of+physics+and+modern+engineering+by+sokolnikoff#customerReviews http://www.amazon.com/Mathematics-Physics-Engineering-Stephe... Each chapter is independent, the text has a thorough index and covers most everything. Few errors, well-illustrated, nicely-sized and pleasant on the eyes. Most easy to read math book ever.

FrankenPC 12y ago

As an analog from the electronics field, look at the Forrest Mims notebook series. That is a superb example of how to take something insanely complex and converting it to no bullshit. The example I saw on the website looks like just another dry math textbook. I've seen high school math books with more color and engaging concepts than this.