[Syzygies]

My Hagoromo chalk and eraser notes:

https://www.math.columbia.edu/~bayer/LinearAlgebra/Video/Cha...

CNN is doing a short web video on this chalk, and I was interviewed last week. They particularly liked my custom attache case for carrying all my colors to teach. When I drew diagrams revealing Catalan number correspondences, they were quite worried that these pictures "weren't math" and I might be hoodwinking them.

The "eraser" is a side category that doesn't get enough attention. At MSRI one uses auto detailing "applicator sponges" which choke pretty quickly with chalk dust, but are nevertheless superior to traditional erasers. Far better is a supply of auto detailing towels; here, Korean microfiber is unrivaled. For classes late in the day, I use one wet to wash the boards, then a dry one to erase as I work. When I run out I do laundry; these towels are indestructible.

So why use the sponges in a public setting? We're learning that animals in many particular tasks exceed human intelligence; it's a matter of each creature's focus of attention. Mathematicians like to believe that we're smarter than average, but we're actually just very focused. That can make us pretty dumb away from our focus of attention. A nervous mathematician giving a public lecture is unlikely to recognize what a towel is for, but a sponge has the right form factor. It's like making your modern heating in a bed and breakfast look like fireplace logs, to not confuse the customers.

[JWKennington]

I too am enamored with Hagoromo; however, I wasn't able to get any of the Japanese chalk. I have been using the South Korean produced Hagoromo and find it quite nice. How do you think the Japanese vs. South Korean produced chalks compare?

Good note about the microfiber! I'll have to try that. I've become increasingly frustrated with erasers. When it comes to washing the board, do you use a squeegee at all? I've found a sponge/squeegee combo to make cleaning quick.

A dimension of chalk usage that seems to be missing from your page - what do you think of chucks (holders)? Hagoromo chalk is quite wide (11mm) and it seems that most chalk holders are built for 9mm chalk. I use the Hagoromo branch chalk holders, they seem to have good grip. The other alternative I've found is to look for artist-oriented graphite or pastel holders.

[Syzygies]

I used to carry a bucket and sponge, then a squeegee, spray bottle, and paper towels. Now I just use a damp detailing towel (not wet enough to drip), and water from the nearest source down the hall. Sometimes one needs to clean the towel and make a second pass to obtain a board that looks newly installed, but generally no squeegee is needed.

Wrong person to ask about holders. I like gripping bare chalk; my hand is too forceful for a holder.

[thanatropism]

> Mathematicians like to believe that we're smarter than average, but we're actually just very focused.

Serious question: does this spell doom for people with ADHD?

[asteli]

It doesn't necessarily. One thing that can come with ADHD is hyperfocus for certain activities. If one has ADHD and an intense interest in mathematics, you might be in luck.

When I was in school, I have a hard time staying engaged in lecture, and homework was near-impossible. I got a C in physics, but set the curve on the tests. It was a fascinating topic, but I couldn't stay focused on the bookwork.

Occasionally I will find a project that fully engages hyperfocus, and it's incredibly satisfying. I once fabricated a motorcycle carrier in a day and a half, pausing only to eat and sleep.

[trentmb]

> Serious question: does this spell doom for people with ADHD?

Caveat: undergrad in math, working on a part time coursework masters (I'm hoping to talk someone into being my advisor for a part time thesis)

No more so than any other academic subject.

If anything, I've found math more friendly to my ADHD than philosophy, literature, etc.

[thanatropism]

I successfully completed an Applied Math masters and defended a dissertation on symplectic integration. But that didn’t quite give me the superpowers my professors had.

[gowld]

In my experience, yes, unless treated with amphetamines.

[raziel2701]

You might be onto something here. Paul Erdos used to consume amphetamines and he was a prolific mathematician.

[jordigh]

I'd be surprised if you get five seconds on the final video. You might also be edited out in a way to make it look like you said something other than what you intended to convey. The Catalan diagrams will almost certainly not make the cut.

[Syzygies]

We'll see! From my experiences with reporters after being the math consultant for "A Beautiful Mind", I share your cynicism. This crew nevertheless impressed me. They'll certainly open with a closeup of my chalk attache case. The Catalan diagrams just didn't fit the prejudices that she imagines of her audience. I was interviewed with these diagrams behind me, so it will be hard to use anything I said without them appearing past my ear.

[patleeman]

You taught me Linear Algebra back in 2013/2014 and I remember you were telling us about this amazing Japanese chalk you were using.

To your credit it was quite good, and produced some really great writing. I wished my other math professors had your passion. Half the time I could barely see the writing on the board after the first erasing.

[jordigh]

Oh, you're Dave Bayer! Sounds like people come to you often.

[Syzygies]

Be surprised.

https://vimeo.com/333758769

[erk__]

Thanks for the infomation, I don't think I have seen anything except Linex chalk while I have been at university in Denmark. So it is interesting that there is people who uses a specific type of chalk.

[malshe]

Thanks for the very interesting info!