Mathematicians Talk (Really, they do)

We all know the joke: “What is the difference between an extroverted mathematician and an introverted one? The extroverted one looks at your shoes, rather than at his own shoes.”

Well, the interviews on Math Tango go a long ways towards dispelling this stereotype that we are conversationally challenged.  “Shecky Riemann” (the pseudonym for the self-described Martin Gardner fan who maintains this blog as well as Math Frolic) has interviewed many eloquent mathematical people (see the list here).   Some things I learned reading the interviews

  • (with Vicki Kearn) how she (an editor at Princeton University Press) goes about choosing mathematical titles and authors to work with.
  • (with Dr. Colm Mulcahy) Richard Dawkins paid Martin Gardner a visit late in his life.
  • (with Dr. Keith Devlin)  Dr. Devlin has some strong opinions about the NSA.
  • (with my co-blogger Evelyn Lamb) We both attribute our becoming mathematicians to taking an Inquiry-Based (Moore Method specifically) course!
Cardioid Microphone -- Yes, you heard that right -- Math is used to amplify itself!

Cardioid Microphone — Yes, you heard that right — Math is used to amplify itself!

Shecky’s blog really focuses on the mathematics community’s relationship to the layman as he is not himself a mathematician, but is fascinated by math. This is reflected in his great posts concerning the role of skepticism in math as well as his reviews of mathematical books for the general public.

But let’s not stop with the interviews here.  A recent post on the aperiodical features a  link to a half-hour interview on the BBC radio program The Life Scientific with Ian Stewart, who is a great popularizer of mathematics.  During the interview he attributes his doing well in math in great part to his mother’s looking out for him in school, and he answers the dreaded question “So… What was you PhD Thesis about?”.  In the course of his answering the interviewer half-jokingly interrupts “It sounds like you just made all this up” referring to the abstractness of the ideas.  That made me laugh because that’s exactly what I do — make things up!!

And just to bring everything full circle, I was reminded that Ian Stewart inherited Martin Gardner’s Scientific American Column.  So this post was really just all about Martin Gardner.  🙂   Incidentally, Martin Gardner Global Celebration of Mind is quickly approaching on October 21st each year (Gardner’s birthday).  Coincidentally, that is the day that I start my new job!  Weird.

Posted in people in math, Publishing in Math, Recreational Mathematics | Tagged , , , , , | 2 Comments

Complex Projective 4-Space

Complex Projective 4-Space recently celebrated its first birthday, and I was surprised to learn it was that young. I’ve been reading since January or so, and I guess I just assumed it had been around longer. It’s written by Adam P. Goucher, a former mathematical olympian (if that’s a term), and it features a wide variety of interesting mathematical topics generally accessible to motivated people with an advanced undergraduate understanding of math.

A visualization of the complex function z^7-1, with Antarctica showing the seventh roots of unity. Image: Adam P. Goucher

A visualization of the complex function (z/2)^7-1, with the 7 Antarcticas showing where the roots of the function are. Image: Adam P. Goucher.

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Rankings, Standards, and Inquiry, Oh my!

Ranking

As concern for K-12 standards in public education has come to a head,  the quality of teaching and learning in our public universities has also come under public scrutiny.  Recently, President Obama announced that he wanted to rework the models used to rank universities and tie public funding to those rankings.  Blogger Cathy O’Neil at mathbabe has some great responses to this idea and points out that there would be many ways to game the system.  As we balk at being judged in bulk by a few isolated measurements, we find ourselves having something in common with K-12 teachers and schools whose positions and funding often hinge on test results.  Tying money to educational results is always a tricky business.  So it might be prudent for us to examine this history of reform in K-12 education.

Standards

Media coverage of the Common Core Standards can make it seem like they emerged from a vacuum.  I was excited to see graduate student Raymond Johnson’s six part series giving a brief history of how the National Council of Mathematics Teachers (NCTM) became involved in policy-making, created the NCTM Standards document, and paved the way for a set of national standards to be adopted.  While the NCTM standards emerged at the end of the Cold War era and followed the report “A Nation At Risk”, the NCTM did not use any public funds to write their standards (although Johnson points out that this may have been simply a consequence of there not being any funding available).  Also, the NCTM’s Standards are not grade specific and were used more as a set of guidelines for the states to write their own curricula.  Johnson is a prolific blogger who spent over 6 years as a high school teacher before returning to school. It is worth noting that Johnson is a University of Northern Iowa alum as he highlights the contributions of professors from UNI several times.

Inquiry

Reading over the Common Core Standards, the most exciting part to a mathematician might be the eight Standards of Mathematical Practice.  These standards highlight some of the characteristics of a mathematician’s mindset as a problem-solver.  For instance, we don’t give up!!  We critique each our work and value rigor.  We seek patterns and are precise in our use of language. So how does one teach students to adopt these mindsets?  Recently there have been many blog posts by Inquiry-Based Learning practitioners aimed at answering these questions.  At Math For Love, Dan Finkel gives his take on teaching perseverance.  At Math Ed Matters, Dana Ernst and Angie discuss creating a supportive classroom environment in which failure is not a roadblock and where criticism can be constructively given and received.  One of Ernst’s June posts was aptly titled with his favorite student comment “Try, Fail, Understand, Win”.  Lastly, at The Math Switch, a blog dedicated to chronicling his transition into using IBL techniques in his classroom, Matt Jones addresses the “start-up” problem of trying to engange students in problem-solving.

Oh my! 

To me, there is an exciting opportunity for K-12 educators and mathematicians to have open discussions about their teaching practices and learn from and support one another.  What’s your opinion?

 

Posted in Issues in Higher Education, K-12 Mathematics, Math Education | Comments Off on Rankings, Standards, and Inquiry, Oh my!

You Get Calculus! And You Get Calculus! Everybody Gets Calculus!

In honor of the beginning of the school year, which is coming in the next few weeks for many of us, I thought you might like opencalculus. Matt Boelkins, a math professor at Grand Valley State University in Michigan, is working on a free, open-source calculus textbook. Active Calculus, which he wrote with the help of his colleagues David Austin and Steven Schlicker, is available for download at Boelkins’ website under a Creative Commons license. Last week, Boelkins announced that it had been endorsed by the American Institute of Mathematics, which reviews and recommends free math resources.

Gabriel's Horn, which has infinite surface area and finite volume and is one of my favorite examples in calculus. Image: Public domain, by RokerHRO via Wikimedia Commons

Gabriel’s Horn, which has infinite surface area and finite volume and is one of my favorite examples in calculus. Image: Public domain, by RokerHRO via Wikimedia Commons.

Textbooks are too expensive. The price is often “what the consumer will bear,” and the student is stuck bearing outrageous prices because the alternative is to have no book at all. Boelkins writes, “it is my opinion that any student of calculus ought to have the opportunity to learn calculus from a text that is free of charge (if used in electronic format), and that instructors ought to have the same freedom, as opposed to being bound to books that cost more than $100 and sometimes even approach $200.” In another post, he paraphrases Robert Ghrist as saying in a talk, “the limiting resource should not be access, but rather time and talent.”

Boelkins notes that there are other good free and low-cost calculus textbooks, but his teaching approach and therefore his text emphasize active learning, and he only includes a few challenging examples in the text rather than lots of simple ones. (He advocates WeBWorK as a good source for other examples and exercises.)

It is probably too late to change your calculus textbook for this semester, but perhaps the opencalculus blog will inspire you for future semesters. Boelkins is also a proponent of the free geometry program Geogebra and has some suggestions for how to use it in calculus class. He will be using Active Calculus in his calculus class this semester and blogging about it as he goes along. I am not teaching calculus this fall, but I will be watching the blog for ideas for next time.

Posted in Math Education, Publishing in Math | Tagged , , , , | 3 Comments

This is your brain. This is your brain on category theory!

I often ponder whether mathematics is lying around waiting to be discovered or is non-existent until we invent it.  One of the most recent posts at Math Rising  led me to a similar question concerning the brain.  Has the physical structure of the brain led us to create certain mathematical structures or did a fundamental sort of mathematics govern the formation of the brain?

Math Rising blogger Joselle DiNunzio Kehoe combs through mathematical papers as well as popular media and blogs like n-Category Cafe looking for mathematical connections between different disciplines including art, physics, and biology.  To find these connections requires one to focus on structure, so category theory is recurring theme.  One of her latest posts focuses on how category theory might describe the means by which we mentally process and sort information.  In particular, she discusses the 2003 article by Ronald Brown and Timothy Porter Category Theory and Higher Dimensional Algebra: potential descriptive tools in neuroscience  The two authors, both mathematicians, propose colimits as a way of describing processes of processes.  The paper also invites discussion with neuroscientists concerning how to use mathematics to connect the activities of a single neuron to formation of a “concept” or “emotion”.   One intuitive advantage to category theory is that regardless of the choices made along the way, the end product is preserved.

196px-Functor_co-cone_(extended).svg

The Universal Property of a Co-limit shown by a diagram — Colimits can be thought of as a way to amalgamate many pieces of information into one.

Ms. Kehoe, who teaches Mathematics at the University of Texas at Dallas also writes for Plus Magazine  and Scientific American about mathematics and cognition.

The idea that category theory is not “abstract nonsense” (as it is so fondly referred to by many a mathematician) was also discussed in Science News back in May by science writer Julie Rehmeyer.  In particular, she mentioned David Spivak’s recent book “Category Theory for Scientists” which is available for free on arxiv.  This book is aimed at a broad scientific audience.

Lastly, the Foundational Questions Institute recently featured the work of John Baez and the quest for the categorification of quantum mechanics.

Posted in Applied Math, Biomath, Theoretical Mathematics | Tagged , , , , , | 1 Comment

Tangled Up in Low-Dimensional Topology

Some knots that are really tangles. In a post about  tangle machines, Daniel Moskovich imagines telling another professional that he, a mathematician, studies knots: "Why knots? Do I want to tie ships to their moorings more securely? What am I up to? Why would a mathematician study knots?" Image: public domain, from Nordisk Familjebok, via Projekt Runeberg, and Wikimedia Commons.

Knots and tangles. In a post about “tangle machines,” Daniel Moskovich imagines trying to explain to an educated non-mathematician what he studies: “Why knots? Do I want to tie ships to their moorings more securely?”
Image: public domain, from Nordisk Familjebok, via Projekt Runeberg, and Wikimedia Commons.

Low Dimensional Topology is, logically enough, a blog about low-dimensional topology. Authors Ryan Budney, Nathan Dunfield, Jesse Johnson, Daniel Moskovich, and Henry Wilton write about 2-, 3-, and 4-manifolds, knot theory, quantum topology, and more Heegaard splittings than you can shake a stick at, if you are in the habit of shaking sticks at Heegaard splittings. Posts are expository but aimed at other topologists, and the authors often cover recent results in their fields. They’ve also written about a number of open problems and keep an up-to-date list of relevant conferences.

Last month Moskovich started a series of posts about “tangle machines,” the subject of a paper he is working on with Avishy Carmi. “Tangle machines aren’t classical knots, or 2-knots, or knotted handlebodies, or virtual knots, or even w-knots. They’re a new object of study which I would like to market,” he writes. This idea of a mathematical idea as a product to be marketed is a bit foreign, but it’s an interesting exercise to think about what your own “marketing strategy” might be for your specific research topic.

Before diving into the glories of tangle machines, Moskovich writes, “I’d like to preface the discussion with a content-free pseudo-philosophical rant, which argues that different approaches to knot theory give rise to different `most natural’ objects of study.” (Personally, I don’t think what follows is cranky enough to be called a rant, but that’s just me.) The rest of the post helped me understand how knots became such an important topic in low-dimensional topology in the first place. In the next post in the series, Moskovich actually defines tangle machines and talks a bit about why he finds them more natural than knots. In future posts, I’m interested in seeing what’s up with Reidemeister moves in tangle machines versus knots.

The LDT archives go all the way back to 2007, but I just want to point out a couple other recent articles I found interesting. In one, Henry Wilton asks, “When are two hyperbolic 3-manifolds homeomorphic?” Although the two manifolds in question, which came from an arXiv paper by Lins and Lins, ended up being relatively easy to tell apart, the advertisement for the Scott-Short algorithm and the comments are quite interesting. I also liked Ryan Budney’s post about the algorithm to recognize the 3-sphere. On many LDT posts, the mathematician whose work is being discussed will often chime in in the comments, clarifying a point or expanding on an idea. So you can read the comments without fearing for your sanity!

It’s always good to see research-level math written in a way that gives more of a big picture overview than most journal articles do and sometimes even offers glimpses into what the hard parts were. The blog is definitely geared toward the research topologist, but other mathematicians can listen in and get a feel for what’s going on in this corner of the mathematical world.

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Dancing Mathy Masters

Creating or finding patterns, reasoning spatially, tending to aesthetics, being precise, and creating in a universal idiom—these are acts common to both math and dance.  

Not everyone is exposed to mathematics via art, especially a performing art.  As a math and dance double major, I recall feeling vindicated when one of my choreography courses required that we build models of both a dodecahedron and a cube as visual aids for spatial awareness.  As of late, both dancers and mathematicians are exploiting these connections for educational purposes. At the primary level, Malke Rosenfeld uses patterns in rhythm and symmetry ideas to promotes choreographic inquiry into mathematical thinking on her blog Math in Your Feet.

From Malke Rosenfeld's Math in your Feet blog

From Malke Rosenfeld’s Math in your Feet blog

Ms. Rosenfeld, a rhythm dancer and homeschooling mother, worked with a math specialist Jane Cooney to meld her passions for dance and math into a way of helping elementary students learn both.   Her video is posted also at a new site called MATHAGOGY which serves as home to a bank of two minute math education videos featuring the “person behind the practice”.  Some of the most experienced math/dance educators might be Erik Stern and Karl Schaffer, two professors, who have developed several activities for upper elementary.  Here is a video showing clips of their ensemble.  A recent article in Proceedings of the National Academy of Sciences (PNAS) highlights their organization, which has been giving dance performances inspired by or demonstrating mathematical ideas for over 20 years.

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The Synergy exhibit at the Simons Center, photography by Gregor Tarjan

Professional mathematicians also find the intersection between movement and math worthy of serious research.  A surprising number of mathematicians enjoy Contra-dancing, the topic of a recent paper entitled “Different partners, different places” which can be found at the Journal of Mathematics and the Arts.  Just last week, Diana Davis, a geometer who won the Physics category of the AAAS-sponsored Dance Your Phd Contest in 2012 (there is no “Math” category), gave a talk at the Simons Center about her work on Veech surfaces.  Her video can be found at this post from last year on Math Munch, one of my favorite blogs.    (If you want to enter the contest or see old video submissions this year you could win $1000, but the deadline is October 2013.)  Currently, the Simons Center is hosting an exhibition Synergy: Dance, Data, Sculpture, which features collaborations between sculptor William Duffy, choreographer William Forsythe, and dance and technology specialist Zuniga Shaw.    The upcoming Bridges Conference in the Netherlands  will include a presentation by Karl Schaffer, as well as three other dance-related presentations.  Tell us about your experiences with mathematics and dance!

Posted in Events, Math Education, Mathematics and the Arts, Recreational Mathematics, Uncategorized | 5 Comments

A Tasty Geometric Morsel Every Day

I don’t remember how I first found Geometry Daily. Probably through Twitter. Every day German graphic designer Tilman Zitzmann posts a “new minimal geometric composition.” It’s not exactly a math blog, but I think many mathematicians will, like me, find the designs beautiful and interesting.

"#247 Bubbles." Image copyright Tilman Zitzmann. Used with permission.

#247 Bubbles. Image copyright Tilman Zitzmann. Used with permission.

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String Art, Bezier Curves, Picasso, and me

linedrawing2 Going through some old boxes at my parents house the other day I ran across some line drawings I made as a teenager.  At the time I found it fascinating that just by drawing straight lines I could create beautiful curves like the boundary of the shape to the left, and I must have drawn hundreds of these pictures.    As a kid my artistic and mathematical tendencies ran parallel without my making many explicit connections between them. Although I realized these curves were parabolas, I didn’t know that they were Bezier curves.  More to the point, I had no idea that all of the drawing programs I liked to use were exploiting the very types of curves that I was drawing by hand.

In 1960’s France, Bezier popularized his eponymous curves (actually invented much earlier) by using them to design cars for Renault.  Around the same time and place Picasso drew his famous line drawings.  After staring at these line drawings, Jeremy Kun, a current graduate student at University of Illinois at Chicago, saw a visual connection between these Frenchmen’s works.  In his May blog post, Bezier curves and Picasso, Jeremy gives an in-depth description of Bezier curves and imitates one of Picasso’s sketches quite handily using nine Bezier curves.

As I read Jeremy’s post, I realized for the first time that my drawings traced out quadratic Bezier curves.  I can’t believe that I never noticed this connection, and now I see a really great and natural way to insert line drawings into college calculus class!  So Jeremy inspired me to create the picture you see below in Inkscape in which I tile the plane.  The Inkscape program has a tool specifically designed for drawing Bezier curves.    Half the tiles are made using this tool, and the other half are made entirely of straight line segments.

linedrawingoriginallinedrawingoriginal

For a better understanding of the recursive nature of higher order Bezier curves and for an understanding of how to decompose these curves, see Jeremy’s excellent explanations.  And don’t skip Jason Davies animation of the recursive construction of a cubic and quartic Bezier curves.

Aside from my own pleasant surprise at the content of this particular post, Jeremy’s blog seems quite unusual in the at the moment due to its accessibility and subject matter (as literally described by his blog’s title) at the intersection of Math and Programming.   While I have noticed many blogs about Complexity Theory and Theory of Computing, I haven’t seen any like Jeremy’s that are well kept up and structured with both theory and code included.  Surely there are more blogs like this?  Let me know in the Comments please!

Speaking of complexity, Jeremy ends his post with some comments about the relationship between complexity and beauty – the general idea being that the more beautiful an object, the less complex.  Might we measure the complexity of a drawing by the number of Bezier curves one needs to draw it?  Unfortunately, as he points out, the beautiful circle cannot be perfectly drawn using a Bezier curve.  This made me think about other line drawings I’ve seen such as those in this July 2nd post created with nested polygons at Benice equation.  Are the spirals traced out by nested squares Bezier curves?  The animations are particularly nice as they allow you to see the way the drawing is generated. There is little or no description of these drawings, but the Geogebra file used to make these drawings is made available.

For more background, see Bridges, String Art, and Bezier Curves, a post from 2012 by Renan Gross, an Israeli student at Technion who has his own blog entitled Sarcastic Resonance.  Although the latest entry is in Hebrew, those previous are English, so don’t let the first one deter you.

Posted in Mathematics and Computing, Mathematics and the Arts, Recreational Mathematics | 3 Comments

Platonic Solids, Symmetry, and the Fourth Dimension

On his blog Azimuth, John Baez has been posting a series called “Symmetry and the Fourth Dimension.” He writes: “The idea is to start with something very familiar and then take it a little further than most people have seen…without getting so technical that only people with PhDs understand what’s going on. I’m more interested in communicating with ordinary folks than in wowing the experts.” He starts with several posts on three-dimensional geometry, focusing on the Platonic solids and their relationship to Coxeter groups, to lay a good foundation before bumping it up a dimension in Part 10.

The icosidodecahedron, a solid "halfway through" the transition from dodecahedron to its dual, the icosahedron. Image: Tomruen, via Wikipedia. Created using Robert Webb's Great Stella software.

The icosidodecahedron, a solid “halfway through” the transition from the dodecahedron to its dual, the icosahedron. Image: Tomruen, via Wikipedia. Created using Robert Webb’s Great Stella software.

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Posted in Math Education, Theoretical Mathematics | Tagged , , , , , , , | 1 Comment