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Sep 8, 2021 at 18:41 answer added Marco Farinati timeline score: 1
Aug 31, 2019 at 2:10 history edited Gerry Myerson
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Aug 30, 2019 at 14:27 answer added Tom Copeland timeline score: 0
Aug 23, 2018 at 0:16 answer added David Roberts timeline score: 2
Jun 12, 2018 at 10:24 comment added Ali Taghavi @KevinH.Lin This is not about the method of presenting "curl" in Multivariable calculus but it is just a comment on a possible reinterpretation of the Curle not as a vector field but as a differential form: mathoverflow.net/questions/291099/…
Jun 10, 2018 at 15:28 answer added isomorphismes timeline score: 1
Jan 15, 2013 at 17:04 comment added Zsbán Ambrus Have you tried to start with the two-dimensional analogs first? Once the students understand the theorems in two dimensions (both the differential and the integral forms), you can motivate curl by saying that it's what makes it possible to have analogous theorems in three dimensions.
Jan 15, 2013 at 16:49 answer added Scott Taylor timeline score: 5
Apr 20, 2012 at 0:54 answer added Jeff timeline score: 3
Feb 16, 2011 at 15:21 answer added John Sidles timeline score: 9
Oct 22, 2010 at 19:02 answer added Tobias Hagge timeline score: 6
Jul 14, 2010 at 0:29 answer added David Corwin timeline score: 9
Jul 14, 2010 at 0:24 comment added David Jordan More importantly, for the one or two students in the class who get excited about this sort of thing, and want to know more, it's a great way to encourage them to take an analysis or differential geometry course. I would say, rather than claiming that curl and div and grad are just the deRham differential, that the deRham differential is really just the next grad, curl and div. Granted, I am making a contentless point here, and I didn't really figure this out until I started TA'ing, but still...=]
Jul 14, 2010 at 0:19 comment added David Jordan I would like to add a comment which doesn't constitute an answer. I have always explained the definition of divergence and curl just as Qiaochu suggests, by starting a proof of Gauss's and Stoke's theorems, computing the flux or divergence integrals on small boxes and deriving the formulas for divergence and curl as a limit. This has the advantage that these two theorems, which are rarely explained or motivated in a calculus class, are essentially self-evident, if one is comfortable with some heuristics about the integral as summing up small contributions.
Jul 14, 2010 at 0:08 answer added Jesse Madnick timeline score: 27
Jul 7, 2010 at 1:59 history edited Yemon Choi
revert (removing visual-math tag as it adds nothing)
Jul 7, 2010 at 1:41 history edited Jose Brox
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May 4, 2010 at 13:41 vote accept Kevin H. Lin
Apr 21, 2010 at 19:12 history rollback Kevin H. Lin
Rollback to Revision 7
Apr 21, 2010 at 19:07 history rollback Kevin H. Lin
Rollback to Revision 6
Apr 21, 2010 at 18:43 answer added Willie Wong timeline score: 3
Apr 21, 2010 at 18:08 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 21, 2010 at 17:01 answer added Donu Arapura timeline score: 10
Apr 21, 2010 at 15:38 answer added Allen Knutson timeline score: 4
Apr 21, 2010 at 12:42 answer added muad timeline score: 8
Apr 20, 2010 at 17:56 answer added B. Bischof timeline score: 6
Apr 20, 2010 at 4:17 answer added Pete L. Clark timeline score: 20
Apr 20, 2010 at 3:35 answer added Christopher Olah timeline score: 2
Apr 20, 2010 at 1:55 comment added Kevin H. Lin @sigfpe: I mentioned that picture already. I'm still curious, though, how one can prove/show/explain that that "intuitive" picture is equivalent to the formula $\nabla \times \textbf{F}$. I'm thinking that something along the lines of Tim Perutz's answer would work.
Apr 20, 2010 at 1:52 comment added Dan Piponi This has always been my intuitive picture of curl: en.wikipedia.org/wiki/…
Apr 20, 2010 at 1:47 comment added Kevin H. Lin Or, if you prefer, you can interpret my question as, "if a student comes to me outside of class and asks for more insight, what should I tell him/her?"
Apr 19, 2010 at 23:09 answer added Tim Perutz timeline score: 52
Apr 19, 2010 at 21:09 comment added Kevin H. Lin What I am really hoping for is some way to convey to them that curl is in fact as natural as gradient and divergence, despite initial appearances.
Apr 19, 2010 at 21:08 comment added Kevin H. Lin @Gerald: Thank you for your advice. I should say that I am certainly not going to try to teach my students about differential forms and the Hodge star. My main issue is just that every time curl comes up, there are inevitably some students who ask about where the "unnatural-looking" formula comes from. On the other hand, they usually don't ask such questions about gradient and divergence, because their formulas "look" natural to them. I don't want to tell them that the curl formula is just some magic formula that has these magical properties.
Apr 19, 2010 at 21:07 answer added some guy on the street timeline score: 11
Apr 19, 2010 at 20:58 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 19, 2010 at 20:54 comment added Gerald Edgar My advice ... at this level, strictly stick to the textbook. If a student comes to you outside of class and asks for more insight, go ahead. But any deviation from the text will likely cause far more confusion that it prevents!
Apr 19, 2010 at 20:50 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 19, 2010 at 20:49 answer added Justin Hilburn timeline score: 5
Apr 19, 2010 at 20:44 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 19, 2010 at 20:36 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 19, 2010 at 20:15 answer added Qiaochu Yuan timeline score: 27
Apr 19, 2010 at 20:13 history edited Kevin H. Lin CC BY-SA 2.5
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Apr 19, 2010 at 19:58 history asked Kevin H. Lin CC BY-SA 2.5