Sheldon Axler

The slides for the talk that I gave at JMM last week (Playing Nice Together: Commuting Operators) are now available at axler.net/conferences.ht… . #linearalgebra

@asdeepak Unfortunately, my talk at JMM will not be streamed or recorded. However, a few days after the talk, I will post the slides for the talk at axler.net/conferences.ht… .

@AxlerLinear Prof. Axler, will this talk be telecast? If not, can we watch a recorded version?

If you are interested in linear algebra and will be at JMM in DC, consider coming to my talk on Tuesday, January 6, at 1 pm. Location and abstract for the talk are available at meetings.ams.org/math/jmm2026/m…. #linearalgebra

@kenzaghib I made some nice changes for the fourth edition. If any of the new topics interest you, then getting the fourth edition will be worthwhile. The pdf file for the fourth edition is legally available for free at linear.axler.net, so you can look at that to help decide.

@AxlerLinear I own beautiful hardcover books of MIRA and of the 3rd edition of LADR, from which I learned linear algebra. Is it worth it to also get the 4th edition? Thanks so much for your excellent and motivating student-friendly textbooks!

I think that the 50% off sale is valid world-wide, not just in the US. To test this, try to purchase Measure, Integration & Real Analysis and enter the coupon code before you give your credit card number.

@AxlerLinear Hey! I’ve got one of those! Really enjoyed it. Might think about getting the other; I got Halmos’s treatment about 40 years ago but it’s heavy going. How would you say it compares? Is this offer US only? I’m in the UK.

Yes, the textbook used for a course can vary as different faculty members teach the course. Measure, Integration & Real Analysis has been used as a textbook at UC Berkeley for the two most recent Spring semesters.

@AxlerLinear I don't recall it being used when I took my analysis class at Berkeley 🤔 maybe it's professor dependent.

I have not yet made videos to accompany my book Measure, Integration & Real Analysis, although I might do so is a few years. The electronic version of the book is legally available on the book's website: measure.axler.net

@AxlerLinear Do you have lecture videos for this course?

@RickyAudet Yes, the Kindle version and the pdf version (see linear.axler.net) are always free.

@AxlerLinear The Kindle version of LADR appears to be free right now.

The slides for the talk that I gave last week (Unlocking Hidden Dimensions: The Power of Generalized Eigenvectors) are now available at axler.net/conferences.ht… . #linearalgebra

The Fall semester is now ending at most universities. If you used the new fourth edition of Linear Algebra Done Right as a textbook this semester, please consider posting a review of the book on Amazon (amazon.com/Linear-Algebra…).

The print version of the fourth edition of Linear Algebra Done Right is available from Amazon at amazon.com/Linear-Algebra… and from Springer at link.springer.com/book/10.1007/9….

@ana_de_noche Empece el libro de @AxlerLinear y me emociono bastante, onda gamas de tenerlo en papel?

se me acaban de llenar los ojos de lágrimas leyendo la metafísica de aristóteles cuentenme ustedes con qué locura andan llorando

See page xvi in the fourth edition of Linear Algebra Done Right for a list of the major changes from the third edition.

@AxlerLinear I have the Third Edition. What are changes in the Fourth Edition?

The free Kindle version of the fourth edition of my book Linear Algebra Done Right is now available at amazon.com/Linear-Algebra…. The free pdf version of the book is available at linear.axler.net. The free translation into Chinese is also available as a pdf file at linear.axler.net. #linearalgebra

All editions of my book Linear Algebra Done Right have included determinants (but near the end of the book to emphasize that determinants are not needed for the key theorems of linear algebra). In the fourth edition, determinants are defined via alternating multilinear forms.

@AxlerLinear Does this one include determinants?

The list of 86 universities that have used my book Measure, Integration & Real Analysis as a textbook is now available at measure.axler.net/MIRAAdoptions.…. #measuretheory #realanalysis #functionalanalysis

@AlgorithmicBot I disagree with the comment above. By this stage in the chapter, readers should know and be comfortable with the easy result that every subspace contains the additive identity. In my opinion, it is unnecessary to restate that result in the proof of 1.45.

who finished "Linear Algebra Done Right" by @AxlerLinear back to back? really liked the first chapter until I came across the last two proofs this proof over here states in the second sentence that "the direct sum implies that the only way to write 0 [...]". But, that is not true. The fact that each subspace must have an additive identity together with the definition of direct sum imply that. Next proof straight after this theorem has some small discrepancies too. I really like this book, but just wonder if I need to fill in some puzzle pieces in these proofs later on too?

@andrewfwheeler Thank you for notifying me about this. The problem is that I listed an incorrect coupon code in my original post. As stated in a corrected post, the correct coupon code is FALL40, which probably will work in Japan.

@AxlerLinear Dear Sheldon, unfortunately the discount only applies in USA. Does not recognize promo code when I try to buy in Japan. 🇯🇵

I do know that the new 4th edition of my book Linear Algebra Done Right is Open Access (due to my request to Springer to make it Open Access). The electronic version of the book is legally free to the world at measure.axler.net.

Bought the Linear Algebra Done Right book (3rd ed). Its a local reprint, I am sure. @AxlerLinear may be unaware of this, but the book is now open access, so probably don't matter. Most foreign books gets reprinted or even photocopied here by local sellers.

The electronic version of the translation into Chinese of my book Linear Algebra Done Right is now legally available without cost at linear.axler.net. #linearalgebra

In Linear Algebra Done Right, F can denote either R or C, but the same choice of F must be made throughout any discussion. Thus in asking "Is R^2 a subspace of the complex vector space C^2?", the field is C because of the phrase "the complex vector space C^2". Note that R^2 is indeed a subset of C^2, so this question makes sense.

@AxlerLinear Hi,Sheldon,Before comparing the relationship between two linear spaces (such as whether A is a subspace of B), should their coefficient fields be unified? The fifth question of Exercise 1. C is somewhat confusing.