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Too Much Calculus – Gilbert Strang (2001) [pdf]

www-math.mit.edu

31–40 of 137 posts

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#31
post #10

(Speaking from my experience as a calc teacher at a big U.S. state U.; mileage may vary elsewhere) Most non-STEM students won't see the 'Calculus I, Calculus II, Calculus III' that starts the essay so dramatically. Increasingly, liberal arts students are able to get by with no more than a "math appreciation" course and maybe what amounts to high school algebra. The "math appreciation" course might actually touch on v…

> Another thing to keep in mind is calculus has had much more impact on history/society than linear algebra.

Yes, it was amazingly important during all the wars and conflicts of the last century.

I don't think it was for the memory of Newton that they choose Calculus, but because it was more useful in a war machine than the alternatives.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#32
post #25

Earlier quoted context omitted.

I'm unfamiliar with it: what is the cliché about multiplication vs exponentiation?

The point is that that vs doesn't even make sense. It's like saying what wheel is your favorite in your car, the front left or the rear left. Arguing for calculus vs linear algebra is equally stupid. They are different branches of mathematics with different domains of application.

This I understand, but that sentence with "cliché" in it I still don't get.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#33
> We need to present the mathematics that is most useful to the most students.

I wish it weren't this way! Mathematics is a wide and fascinating field, and I think more students could find interest if our schooling reflected that. But moving some of the detail and drudgery that is the calculus sequence to subject matter that requires it, in order to make way for linear algebra, is a great start.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#34
post #3

I watched Prof. Strang's Linear Algebra courseware, great stuff. He is a wonderful teacher. http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-... As someone who hadn't studied it for 20 years, it was invaluable to revisit the subject as an adult with the ability to reflect "ah, I can use that for... " instead of "Ok but when am I ever going to use this"

As someone who did work at a University who also loved classes I would bring friends who were visiting to classes and every time they would say something like this, "I hated Philosophy as a college student, but somehow now I loved every second of that class." They were always surprised by that experience.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#35
post #3

I watched Prof. Strang's Linear Algebra courseware, great stuff. He is a wonderful teacher. http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-... As someone who hadn't studied it for 20 years, it was invaluable to revisit the subject as an adult with the ability to reflect "ah, I can use that for... " instead of "Ok but when am I ever going to use this"

His lectures are wonderful! In college I skipped my regular Linear Algebra lectures, and used the time slot in my schedule to watch his MIT lectures instead. I ended up scoring one of the highest grades in the class.

Finding out the Fourier transform was a way to multiply matrices was a mind blower :)

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#36
post #10

(Speaking from my experience as a calc teacher at a big U.S. state U.; mileage may vary elsewhere) Most non-STEM students won't see the 'Calculus I, Calculus II, Calculus III' that starts the essay so dramatically. Increasingly, liberal arts students are able to get by with no more than a "math appreciation" course and maybe what amounts to high school algebra. The "math appreciation" course might actually touch on v…

I'm amazed that you say that calculus has had a much greater impact on society when virtually every database, graphics manipulation or economic analysis uses principles of linear algebra. Can you substantiate "millions of transfer students between thousands of universities every quarter"? That seems like outlandish hyperbole. Irrespective of the precise number, a system with momentum is not sufficient justification f…

>I'm amazed that you say that calculus has had a much greater impact on society when virtually every database, graphics manipulation or economic analysis uses principles of linear algebra.

I'm not. Consider all of physics. Physics is written down in terms of differential equations. You need calculus to get these equations. In terms of graphics, for example, are you magically creating only static images that never change in time? How do you think people came up with the algorithms to do things like refraction or reflection? These all involve calculus. Calculus is the most important tool in applying mathematics to the real world. It is how we derive the models for pretty much everything I can think of. Any time you want to model something where anything changes, that is calculus. Any time you want to find an optimal solutions, that is calculus. I can't think of a single area of applied mathematics that doesn't use calculus in some form. Even mathematics in general, calculus is used in some form pretty much everywhere in some form, except maybe in the foundations of mathematics like set theory or logic.

Solving them, on the other hand, is a different problem. This is where linear algebra is important. When solving an ODE or PDE, when I discretise it, all I am doing is re-writing it as a giant linear algebra problem. Quantum mechanics, for example, is dedicated to finding the eigenvalues and eigenvectors of the Hamiltonian. Linear algebra provides the tools to solve the problems posed by calculus. But it isn't always required.

In fact, if you look at the history of linear algebra, it only really became wide-spread when quantum mechanics was developing since there is a deep connection between linear algebra and quantum mechanics. Heisenberg had never heard of a matrix before despite discovering Heisenberg matrix mechanics. He was told by Max Born that what he had been doing is actually this thing mathematicians called "matrices". Now linear algebra is a required course for physicists (incidentally, linear algebra was the first lecture I ever attended at university).

So I would argue that learning calculus is the most important thing someone should know mathematically, since it is the tool we use to build models. The second most is linear algebra since it provides us the tools to solve these problems. But in my mind, knowing how to derive these models is a lot more important than being able to solve them. That and linear algebra doesn't give you any insight into why we are solving the problem that way, it is just a tool to solve the problem.

Also in Calculus 1,2,3 and so on, you learn increasingly more complicated techniques of calculus to solve more problems. But when you start numerically solving them, linear algebra doesn't care. It doesn't care if your equation came from the Einstein field equations or Newton's second law. It's all the same to it. So in a sense, I can teach you everything you'll need to know about linear algebra in a single course but the same is not true of calculus, which requires multiple courses.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#37
post #6

Perhaps amusingly, the Computer Science education at the University of Copenhagen includes no mandatory Calculus course, but it does include a Linear Algebra course. Even so, students have a hard time seeing what they'll use Linear Algebra for, before later on in their education.

Personally, I skipped taking Linear Algebra in college, because I assumed it was basically 'Algebra II' and intended for people who weren't taking math-intensive tracks, like liberal arts majors. Although thankfully in my 3D graphics programming class we spent some time on Linear Algebra, so I got my misconception cleared and saw how it was useful (even though it looked like Voodoo magic to me how it worked for most of that class).

So yeah, maybe I'm just an outlier, but part of it may be a naming issue also. "I already took Algebra way back in 8th grade and it was a breeze! I don't need to take another Algebra class!"

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#38
post #3

I watched Prof. Strang's Linear Algebra courseware, great stuff. He is a wonderful teacher. http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-... As someone who hadn't studied it for 20 years, it was invaluable to revisit the subject as an adult with the ability to reflect "ah, I can use that for... " instead of "Ok but when am I ever going to use this"

Those lectures are fantastic. Pro-tip: watch them at 2.5x speed (you'll keep up just fine, and you can always pause to play with the concepts in Sage or whatever).

Bonus: when you switch him back to normal speed, he sounds stoned out of his mind.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#39
Anyone interested in getting started with linear algebra can check out this printable tutorial: Linear algebra in four pages: http://minireference.com/blog/linear-algebra-tutorial/

The page also links to another short tutorial which explains more of the geometric intuition behind linear transformations.

Neither tutorial can serve as a full course, but reading them will give you a good overview of what linear algebra is about.

Re: Too Much Calculus – Gilbert Strang (2001) [pdf]

#40
post #25

Earlier quoted context omitted.

The point is that that vs doesn't even make sense. It's like saying what wheel is your favorite in your car, the front left or the rear left. Arguing for calculus vs linear algebra is equally stupid. They are different branches of mathematics with different domains of application.

This I understand, but that sentence with "cliché" in it I still don't get.

It's pretty clear to me that the OP just used the word cliche where it didn't belong. Fortunately the idea still came across. Perhaps you were truly confused, but it sounds more like you're playing dumb to force the OP to admit the mistake.
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