The equation-filled blackboard is one of the most reliable props of academia, not just in cartoons and movies, but in real life. You know a scientific discussion is taking a turn for the serious when the protagonists head to the board. Walking into a colleague's office, a glance at the scrawled notes on their board gives you a taste of their current research preoccupations and teaching commitments; wobbly chalk drawings along the bottom edge are a pretty good sign that the office's owner has a small child in their life. Blackboards are found in the corridors of academe as well as the offices and classrooms. And at the Isaac Newton Institute for Mathematical Sciences in Cambridge, every bathroom stall has a small chalkboard, just to be on the safe side.

I've got blackboards on the mind because they have been popping up in my Facebook feed over the last few days, thanks to this advertisement for something called Creative Physics 5.0:

Those Ivy League Professors can certainly keep a secret; I spent most of the last 20 years in Ivy League physics departments and never once saw Creative Physics, nor that many young men in full jacket and tie. But in my patch of ivy, blackboards were certainly ubiquitous.

Where I work now, though, whiteboards rule the roost, and I find myself missing the timbre of chalk on slate, and even the chalkdust on my fingers. So when this one popped up on my screen, I couldn't help taking a closer look. It sports an authentic palimpsestic underlay of previous scribblings, a couple of nifty plots, a trig function or two, and a liberal sprinkling of superscripts (n, 2, and the ambiguous o) that always give a blackboard a sophisticated look. It's great to see the lemniscate get an outing here, too, even if the equation in which it guest-stars doesn't add up to much.

Best of all is the triangle, whose internal angles total 90 degrees rather than the conventional 180. Good old non-Euclidean geometry. 

A Google image search reveals that this is a stock photo, so the creators of Creative Physics are responsible merely for selecting it, not for its eccentricities. (Good news: "stock-photo-blackboard consultant" is clearly a vacant niche for an enterprising physics student.)

But select it they did. There's a pleasant irony in promoting a computer-based learning system with an image of an ancient piece of hands-on edu-tech. You'd think the blackboard's cultural stock would be on the wane; chalkboards conjure images of lecturers transcribing old notes while standing with their back -- literally and metaphorically -- to the class. In a world where students download snippets of instruction from Khan Academy, the chalkboard could look like a dusty relic.

But on a good day, "the board" conjures a momentary collaborative community. There's a shared, dynamic connection when a talented teacher takes a stick of chalk and walks a class through an argument in real time, duster and all. Physicists often speak of performing a calculation, and in the right hands the chalk and the board can be magical

Personally, i am enormously excited by the plethora of new tools for teaching physics (or indeed any subject) -- e.g. MOOCsflipped classrooms or studio physics. But just as movies, radio, TV and YouTube did not spell the end of live concerts and theatre, I suspect the live lecture will keep a place in the academy, as will the good old board, whether black or white.

And for fans of ivy covered professors in ivy covered halls, here's some Tom Lehrer...