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Watch out! I’m a blue whale and I’m about to land on you!


I don’t know why this question popped into my head, but it’s been sitting there for the past week and showing no signs of moving on.

Suppose an enemy of mine threw a friendly blue whale at me. Being a friendly whale, it makes the blue-whale-noise equivalent of “DUCK!” to warn me it’s coming.

How quickly does the whale need to be travelling for its warning to be useful?

Apparently I’m not a maths genius (or, On the Subject of Parcel Sizes)

This article on BBC News caught my eye because it has “maths” in the headline. Yes, I’m that easily pleased.

Somewhere in the middle, it says that myHermes requires the “volumetric area” of a parcel to be less than 225cm. That’s right: the “volumetric area” is neither a volume nor an area but a length. Anyway, the formula for volumetric area of a package with sides $a,b,c$, where $a \leq b \leq c$, is

\[ 2(a+b) + c \]

(Importantly, $a$ and $b$ are always the two shortest sides of the package)

So the constraint is

\[ 2(a+b) + c \leq 225 \]

In the next paragraph is the puzzling statement that the maximum allowable volume for a package is $82.68$ litres, or $82680$ cm3. How did they get that?

I decided to do some calculus of variations, or whatever it’s called.

There’s a new StackExchange site for History of Science and Maths

Just a little note to let you know that there’s a new StackExchange Q&A site for “History of Science and Maths”. Some of the maths questions that have already been asked include:

So if you’ve got a burning question about Maths in the Past, there’s now a place to ask it.

Visit the site:

Is this a nonsense formula for the perfect TV episode?

Stardate November, 2014. These are the continuing adventures of the website The Aperiodical. Its mission: to explore the pages of strange newspapers, to catalogue nonsense formulas, to boldly disapprove of them in ways no blog has done before.

What a joy it was to open my browser this morning and see this delicious headline waiting for me:

perfect tv formula

(by the way, most of the links in this post contain Downton Abbey spoilers. You have been warned.)

In a way, I’m beginning to like nonsense formula stories. You could say that

me + nonsense formula x q = happiness x 2

So, what’s going on this time? Who commissioned it, who sold their soul, and most important of all, does the formula make the least jot of sense?

Le Livre de l’Incomplétude is a lovely take on incompleteness


This is a really nice idea. Le Livre de l’Incomplétude (The Book of Incompleteness) is an “artistic appropriation of Gödel’s incompleteness theorem,” initiated by artist Débora Bertol. The superficial understanding of that theorem is that every consistent formal theory contains truths which can’t be proved inside that theory, so the book’s conceit is that it will catalogue as many different arithmetic formulas as possible that evaluate to each of the numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.

I think it’s a really charming take on one of the most abstract and hard-to-understand subjects in maths.

The conclusions you can draw from this graph will SHOCK you

This is a blog post based on a Google+ post about a tweet. I can only hope that it will inspire a further flourishing of vines, instagrams and Yo!-s.

I saw this graph (originally from job stats site posted by a functional programming news site:


The accompanying tweet said

“More reasons to choice Functional Programming – #Clojure and #Haskell highest paying #engineer salaries!”.

Well, should I “choice” Haskell or Clojure, based on the evidence in this graph?