Geometric Algebra for Electrical Engineers

A price increase for Geometric Algebra for Electrical Engineers

May 28, 2020 Geometric Algebra for Electrical Engineers No comments , , , ,

As of this week (end of May 2020), I raised the price of the black and white version of my Geometric Algebra book slightly (from $12 to $14.50 USD).  I say slightly, despite the 17% price increase, because the price is still pretty low from an absolute value perspective, as the markup I’d added to the minimum price was fairly small.  This price increase was an experiment in response to a reseller (SuperBookDeals) buying copies at $12 and then reselling them at higher prices.  For some reason amazon lists the higher price reseller copies before their own kindle-direct-publishing version, so a buyer had to go out of their way to find the lowest priced version.

I wouldn’t care if resellers undercut my list price, and then got a preferential listing from amazon.  The fact that this reseller doesn’t play this game with the color version of the book, which has a much higher printing cost (I haven’t changed my price for that, and am still selling it for $40 USD), suggests to me that I’d set the price too low for the black and white version.

If you are interested in a copy of the book, but don’t like the new higher price, please note that the (color) PDF version is still available for free.

I may drop the price back to the original $12 later, but for now I’m going to charge $14.50, and am curious to see how the pricing game plays out.

Note that a temporary side effect of me having changed the price is that SuperBookDeals appears to have dropped their price of one of their listings below $12 (my original price) to clear out their stock. Amazon also appears to be offering a couple copies at the old $12 price, which now lists as a sale price.


Finding the cheapest copy of my geometric algebra book on amazon

May 3, 2020 Geometric Algebra for Electrical Engineers 1 comment , , ,

My book, “Geometric Algebra for Electrical Engineers” is available as a free PDF here on my website, but also available in color ($40) and black-and-white ($12) formats on amazon.  Both versions are basically offered close to cost, should the reader be like me, preferring a print copy that can be marked up.  In fact, I made it available initially just so that I could get a cheap bound copy for my own use that I could mark up myself.

I noticed today that amazon now hides the cheapest version of my book, and seems shows the price of a reseller first.  For example, if you click the link to the $12 black-and-white version, it now appears that the book is selling for $13.01

but if you click on “Other Sellers”, the kindle-direct (print on demand) version that amazon offers itself hides further down in the list of sellers.  The version that I’m selling directly through is third on the list, despite it being the cheapest:

I guess that I’ve priced the black-and-white version of the book so low, that there are resellers that are willing to try to make some profit selling their own copies.  Do they depend on amazon giving them preferential listing order to make those sales?  I wonder how many of the people who have bought my book have ended up accidentally paying a higher price, using one of these resellers?

It does not appear that any resellers have played this game with the color version of the book, which has a higher price point.  I’m curious now to look at the sales stats for the two variations of the book to see how many of each version are selling (hardly any in either case, as the subject matter is too esoteric, but it was actually enough over the whole year that I did include the revenue on my income taxes.)

Amazon’s kindle-direct now has Canadian manufacturing

December 14, 2019 Geometric Algebra for Electrical Engineers No comments , ,

As a “kdp” author, I got an email about new Canadian manufacturing for kindle-direct orders (i.e. my Geometric Algebra book and various UofT physics and engineering class notes compilations.)

Here’s a fragment of that email:

“We’re excited to announce paperback manufacturing in Canada! This enables new features for KDP authors, including:

    • Faster shipping to your readers in Canada. Manufacturing in Canada enables FREE Two-Day Shipping for Prime Members.

Please note that, as of today, proof copies and author orders for authors in Canada will still be printed and shipped from the US.”

With the low price that I set my book prices at, paying just the US shipping for an “author proof” has been about the same as ordering a normal copy, so now there will really be no point to ordering proofs anymore.

“2nd” edition of “Geometric Algebra for Electrical Engineers”

May 4, 2019 Geometric Algebra for Electrical Engineers No comments

I’ve refreshed my Geometric Algebra for Electrical Engineers book, which could be considered a 2nd edition of sorts. The amazon color and black-and-white versions have been updated, as well as the pdf and the leanpub version (all of those are in available in the previous link.)


V0.1.15-6 (May 2, 2019)

  • Update figures (thicker lines, remove some ticks, …) and link them to the mathematica link anchors.
  • “in figure fig.” -> “in fig”.
  • Extend my hacks of the classic thesis template to use 6×9 with smaller than default margins. Now have the preface page numbers not in the bleed area of the page.
  • Split colorlablebox into separate .sty (for phy452 notes.)
  • Fix pdfbookmarks for contents and list of figures (so that they don’t show up under the preface)
  • Index quaternion (Bruce Gould)
  • GAelectrodynamics.tex: Want scrheadings starting before contents otherwise page numbers are out of bounds (and the page headings are MIA)
  • Bruce: “May I suggest that the proofs should have the end-of-proof symbol at the end?” Used the amsthm proof environment to do this.
  • Theorem 1.2: turn the converse into a footnote, to be seen later. (Bruce)
  • Added Bruce Gould to the thanks.


Why to study electromagnetism with geometric algebra.

February 3, 2019 Geometric Algebra for Electrical Engineers No comments

The current draft of my book really ought to have some motivation in the preface. This is what I was thinking of.

Why you want to read this book.

When you first learned vector algebra you learned how to add and subtract vectors, and probably asked your instructor if it was possible to multiply vectors. Had you done so, you would have been told either “No”, or a qualified “No, but we can do multiplication like operations, the dot and cross products.” This book is based on a different answer, “Yes.” A set of rules that define a coherent multiplication operation are provided.

Were you ever bothered by the fact that the cross product was only defined in three dimensions, or had a nagging intuition that the dot and cross products were related somehow? The dot product and cross product seem to be complimentary, with the dot product encoding a projection operation (how much of a vector lies in the direction of another), and the magnitude of the cross product providing a rejection operation (how much of a vector is perpendicular to the direction of another). These projection and rejection operations should be perfectly well defined in 2, 4, or N dimemsions, not just 3. In this book you will see how to generalize the cross product to N dimensions, and how this more general product (the wedge product) is useful even in the two and three dimensional problems that are of interest for physical problems (like electromagnetism.) You will also see how the dot, cross (and wedge) products are all related to the vector multiplication operation of geometric algebra.

When you studied vector calculus, did the collection of Stokes’s, Green’s and Divergence operations available seem too random, like there ought to be a higher level structure that described all these similar operations? It turns out that such structure is available in the both the language of differential forms, and that of tensor calculus. We’d like a toolbox that doesn’t require expressing vectors as differentials, or resorting to coordinates. Not only does geometric calculus provides such a toolbox, it also provides the tools required to operate on functions of vector products, which has profound applications to electromagnetism.

Were you offended by the crazy mix of signs, dots and cross products in Maxwell’s equations? The geometric algebra form of Maxwells’s equation resolves that crazy mix, expressing Maxwell’s equations as a single equation. The formalism of tensor algebra and differential forms also provide simpler ways of expressing Maxwell’s equations, but are arguably harder to relate to the vector algebra formalism so familiar to electric engineers and physics practitioners. In this book, you will see how to work with the geometric algebra form of Maxwell’s equation, and how to relate these new techniques to familiar methods.

My book (Geometric Algebra for Electrical Engineers) now available in paper.

January 29, 2019 Geometric Algebra for Electrical Engineers No comments

Edition 0.1.14 of my first book, Geometric Algebra for Electrical Engineers is now available, in a variety of pricing options:

Both paper versions are softcover, and have a 6×9″ format, whereas the PDF is formatted as letter size.  The leanpub version was made when I had the erroneous impression that it was a print on demand service like kindle-direct-publishing (aka createspace.) — it’s not, but the set your own price aspect of their service is kind of neat, so I’ve left it up.

If you download the free PDF or buy the black and white version, and feel undercharged, feel free to send some bitcoin my way.