Puzzlebomb is a monthly puzzle compendium. Issue 1 of Puzzlebomb, for January 2012, can be found here:
Puzzlebomb – Issue 1 – January 2012
The solutions to Issue 1 can be found here:
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Implied Geometry by Jim Sanborn
Implied Geometry by Jim Sanborn:
Nobel prize for mathematics
There’s no Nobel Prize for Mathematics
This is a common statement. I’ve certainly used it myself. Recently it occurred to me to be annoyed with this.
Nobel Prizes are awarded in physics, chemistry, medicine, literature, peace and economics, but not mathematics.
On the other hand, mathematics is widely applicable and I think I could convince you it is certainly used in physics (career), chemistry (career), biology (career), medicine (career) and economics (career). (Links to the excellent Plus Magazine and Maths Careers.) The case for literature and peace might be a bit harder to sell. But even without these two we still have a majority.
So perhaps from now on I will try to remember to say:
Most of the Nobel Prizes are for Mathematics1
[1. there is a fallacy here: for example, saying that some mathematics can be applied to economics does not mean that all economics involves mathematics. But, shh!]
Christmas presents
What did I get for Christmas (mathematically, at least)? My big present was an Acme Klein Bottle, whose website claims it to be one of “the finest closed, non-orientable, boundary-free manifolds sold anywhere in our three spatial dimensions”. This is a 3D representation of a 4D Klein bottle; a pale shadow, of course, although the cheerful and entertaining information leaflet that came with the bottle claims this an advantage: “You can actually hold an Acme Klein Bottle in your hand. Those highfalutin’ 4-dimensional ones can only be held in your mind”. Here is a photo of mine:
I also got a set of physical puzzles which are nice to have a supply of. I find I am sometimes laying puzzles on a table for students to play with and solid, physical puzzles, while perhaps not the most mathematically interesting, are certainly an attractive draw. People can’t resist picking up and playing with wooden blocks, it seems!
I got a copy of The Great Mathematicians by Raymond Flood and Robin Wilson, a past and present President of BSHM, which claims to present “mathematics with a human face, celebrating the achievements of the great mathematicians in their historical context”. You can watch a lecture given by Raymond and Robin at the launch of the book at Gresham College.
As a bit of Christmas day craft, inspired by the escapades of the Manchester Maths Jam, we made dodecahedron star lanterns. Unlit, these are like this:
And lit they come alive like this:
Merry Christmas everyone! What mathematical presents did you receive and what mathematical activities did you do this year?
Pictorial proofs
I received this message from Alan Stevens, Nottingham Maths Jam attendee. I am putting it here so readers of this blog and the other Maths Jams might consider the topic as well.
Although I won’t be able to make the next MathsJam at Nottingham I’ve thought of a theme you might like to consider. I don’t know if you have themes, but, if you do, how about “Pictorial proofs and derivations”?
Probably the most obvious pictorial proof is of Pythagoras’s theorem (in fact there are probably several such). Do your mathsjammers know of any more?
I thought of this while viewing James Tanton’s YouTube channel, where he has a very pictorial way of looking at maths, including a very nice pictorially based derivation of the geometric series 1/3 + 1/3^2 +1/3^3 + … = 1/2.
If you haven’t seen someone in a t-shirt displaying a pictorial proof of Pythagoras, you haven’t been going to the right sort of conferences! The James Tanton video reminds me of a pictorial demonstration of summing 1/2 + 1/4 + 1/8 + … which I used in a lecture, after Zeno’s paradox of Achilles and the tortoise, when I was trying to get across the idea of an infinite series summing to a finite amount. Shading half a square, then a quarter, then an eighth, and so on it looks like you will eventually shade the whole square and nothing more, a useful illustration that the series converges to one. In fact, I repeated this in the micro-teaching session of my Postgraduate Certificate in Higher Education course and a screenshot of the slide after I drew on it using the interactive whiteboard is below. I’m not sure if this constitutes a proof, though.
Figurative Sculptures by Manuel Martí Moreno
Figurative Sculptures by Manuel Martí Moreno:
Why I like some bad maths stories
My two most recent posts here have been about a story reporting a coincidence as more exceptional that it is and ‘bad maths’ reported in the media. Both are examples of mathematical stories being reported in a way that is not desirable. Somehow, though, I like the whist story and dislike the PR equations. I have been thinking about why this might be the case.
The PR-driven, media-friendly but meaningless equations from the first article are annoying because they present an incorrect view of mathematics and how mathematics can be applied to the real world. Applications of mathematics are everywhere and compelling, yet the equations in these sorts of equations seem to present little more than vague algebra. The commissioned research with seemingly trivial aims I find more difficult because, as commenters on that article pointed out, it is really difficult to decide what is trivial. Still, reporting that a biscuit company has commissioned research into biscuit dunking is either meaningless PR or else a matter of internal interest, and certainly nothing like what I expect mathematicians do for a living.
Coming back to our Warwickshire whist drive: what do I like about this story? It too presents incorrect information about mathematics and the real world, claiming that the event, four perfect hands of cards dealt, is so unlikely that it is only likely to happen once in human history (and it happened in this village hall!).
I think the difference is that the mathematics used, combinatorics and probability, appear to be correctly applied. The odds quoted, 2,235,197,406,895,366,368,301,559,999 to 1, are widely reported and I see no reason to doubt them.
The problem, then, is one of modelling assumptions. Applying a piece of mathematics to the real world involves describing the scenario, or a simplified version of it, in mathematics, solving that mathematical model and translating the solution back to the real world scenario. In this case, the description of the scenario in mathematics assumes that the cards are randomly distributed in the pack. This modelling assumption, rather than the mathematics, is where the error lies.
The result is still a bad maths news story, presenting a mathematical story as something other than what it is, but while the PR formulae are of little consequence, this incorrect application of a correct combinatorial analysis is something we can learn from.