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No bullshit guide to math and physics

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Re: No bullshit guide to math and physics

#102

Post by oneandoneis2 »

TylerE wrote: post #74
phaus wrote: post #50

Earlier quoted context omitted.

Please listen to this guy's suggestion of making the price for both only marginally higher than the price for the Print version alone. One of the quickest ways to kill my interest in in purchasing a book is by expecting someone to pay a non-trivial amount of money for a digital copy after they just purchased a hard copy at full retail. As far as pricing the ebook alone, I think it should be somewhere around 14.99 to…

Why is it acceptable in 2013 to charge ANYTHING for a digital copy when also buying the dead-tree?

If it were a one-off download, it probably wouldn't be. But I quite like the system O'Reilly uses: $5 for an ebook if you own the dead-tree version, because you can download it as many times as you like, in all different formats, and they maintain it with errata updates etc. for life.

The lifetime ability to download the most-current version of a book in any current format is, IMO, worth a few dollars more than a free but unmaintained ebook in what may very easily become a legacy format within a few years.

Re: No bullshit guide to math and physics

#103

Post by crntaylor »

I applaud the idea, but I think this book needs some serious work before it is suitable for your intended audience.

For example, in Section 1.1 you explain how to go about solving the equation x^2 - 4 = 45, a topic which (I would venture) most 16 year olds should be comfortable with.

Then in Section 1.2 you, out of nowhere, introduce set-theoretical ideas and notation. Even seemingly innocent notation like

    {0, 1, 2, 3, ...}
to denote the natural numbers can be confusing for someone who hasn't seen it before. In this case it's clear that the dots are supposed to indicate "continue in the obvious way". But then you write

    Q = { -1.5, 1/3, 22/7, 0.125, ... }
in which the dots, presumably, mean something different. Then, at the bottom of the page, you suddenly start using the notation "∈" to denote set membership, as in

    if x,y ∈ N, then (x+y) ∈ N.
First, what does this weird "∈" symbol mean? Second, what does it mean to write "x,y ∈ N"? Is that x∈N and y∈N? Or is it some special object "x,y" that is ∈N? Or is it two statements, "x" on its own, and "y∈N"?

The next couple of paragraphs contain both historical and mathematical inaccuracies (can you really always divide two rational numbers to get another rational number?). I'll stop there.

Like I say, I applaud what you're trying to do. I think you have a noble aim. But if the preview is anything to go by, your textbook in its current form is falling short of that aim.

Re: No bullshit guide to math and physics

#104

Post by boothead »

smortaz wrote: post #64

random idea - consider making some examples/sections from the book also available as an IPython notebook. IPython+matplotlib+numpy+scipy is a perfect quartet for getting some ideas across in an interactive, intuitive way. best of all the reader doesnt have to setup anything. just include some URLs in your book. see: http://ipython.org

Yes! I've been away from math for so long that having code that translates the math notation would be really helpful!

Re: No bullshit guide to math and physics

#106

Post by swatkat »

Nice! I'd buy ebook when it's out. BTW, I also recommend "The Joy of x: A Guided Tour of Math, from One to Infinity" (http://www.stevenstrogatz.com/the_joy_of_x.html). This amazing book rekindled my interest in Mathematics. Now, I've got a couple of math books in my 'to-read' list.

Re: No bullshit guide to math and physics

#107

Post by serf »

walexander wrote: post #72
pflats wrote: post #39

I read the first 10 pages of the pdf. I'm not sure who you think your target audience is, but this book doesn't seem to serve any of them. You gloss over huge sections of algebra, and in doing so, ignore incredibly common mistakes that students make. Take a look at the top of page 9, 6 \sqrt{x} - 7 = [...]. You solve that out, but give no reason as to why you got rid of the 7 first, the 6 second, and the radical thir…

Since you seem to be informed about the books out there that are attempting what the OP's book is, what would you suggest in place of it? Seems like even with the problems you've listed, it might still fit a niche that I haven't seen filled very well.

I , too, would love a list of 'casualized' textbooks. I was interested in the premise of this, but the flaws i've caught thus far (the newton/natural number thing got me too) have made me lose confidence in the rest of the book.

Re: No bullshit guide to math and physics

#108

Post by anonymouz »

madhadron wrote: post #48

I hesitated to post this, since I think clearer, shorter, better written textbooks are an admirable goal, and I keep a (short) list of good text books I have found over the years. But based on the preview on the website, I'm going to keep referring those who ask me to Gelfand's wonderful basic math texts instead (Algebra, Method of Coordinates, Functions and Their Graphs, Trigonometry -- anyone who wants further poin…

Indeed, stating that these objects result from some classification of all number-like objects seems misleading at best: Most mathematicians would, just as one example, certainly consider p-adic numbers as number like objects.

It would be better to point out what really matters in the hierarchy N, Z, Q, R, C:

Everybody will accept that N is an interesting object for counting.

Z is the quotient group of N under addition, more elementary: In Z you can compute arbitrary differences of elements of N, and it is the smallest "reasonable" such object.

Similarly, Q is the quotient field of Z, i.e. "the smallest reasonable object containing Z that allows division of non-zero elements".

R is the completion of Q under a natural metric (i.e., "fills the gap on the number line of Q"), and therefore allows one to have a reasonable notion of limits and calculus.

C finally is the algebraic closure of R, so that every non-constant polynomial has a root in C.

Thus, these objects are all constructed from the natural numbers to satisfy certain "niceness" properties.

Of course, it would take quite some space to explain this in a very elementary fashion. So perhaps it is instead better to simply refrain from such a statement in a textbook aiming for shortness above all, or at least make sure that any statement in this direction is substantiated and supported by a suitable reference to a place where your readers can learn more.

A textbook that gains conciseness from vague statements and half-truths would seem to be much worse than a textbook of twice the length that explains its content well.

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