# return of the cat ceilidh

I couldn't believe my eyes. I was watching an episode of numb3rs, 'undercurrents' to be precise, and there it was, circled in the middle of the blackboard, CEILIDH, together with some of the key-exchange maps around it...

Only, the plot doesn't involve any tori-crypto... okay, there is an I-Ching-coded-tattoo which turns out to be a telephone number, but that's all. Still, this couldn't just be a coincidence. Googling for 'ceilidh+numbers' gives as top hit the pdf-file of an article Alice in NUMB3Rland written by ... Alice Silverberg (of the Rubin-Silverberg paper starting tori-cryptography). Alice turns out to be one of the unpaid consultants to the series. The 2-page article gives some insight into how 'some math' gets into the script

Typically, Andy emails a draft of the

script to the consultants. The FBI plot

is already in place, and the writers want

mathematics to go with it. The placeholder "math" in the draft is often nonsense or

jargon; the sort of things people with no

mathematical background might find by

Googling, and think was real math. Since

there's often no mathematics that makes

sense in those parts of the script, the best

the consultants can do is replace jargon

that makes us cringe a lot with jargon that

makes us cringe a little.From then on, it's the Telephone Game.

The consultants email Andy our suggestions ("replace 'our discrete universes'

with 'our disjoint universes'"; "replace

the nonsensical 'we've tried everything

-a full frequency analysis, a Vignere

deconstruction- we even checked for

a Lucas sequence' with the slightly less

nonsensical 'It's much too short to try

any cryptanalysis on. If it were longer

we could try frequency analyses, or try

to guess what kind of cryptosystem it is

and use a specialized technique. For example, if it were a long enough Vigenere

cipher we could try a Kasiski test or an

index-of-coincidence analysis'). Andy

chooses about a quarter of my sugges-

tions and forwards his interpretation

of them to the writers and producers.

The script gets changed, and then the

actors ad lib something completely dif-

ferent ('disjointed universes': cute, but

loses the mathematical allusion; 'Kasiski

exam' : I didn't mean that kind of 'test').

She ends her article with :

I have mixed feelings about NUMB3RS. I still have concerns about the violence, the depiction of women, and the pretense

that the math is accurate. However, if NUMB3RS could interest people in the power of mathematics enough for society

to greater value and support mathematics teaching, learning, and research, and

motivate more students to learnthat would be a positive step.

Further, there is a whole blog dedicated to some of the maths featuring in NUMB3RS, the numb3rs blog. And it was the first time I had to take a screenshot of a DVD, something usually off limits to the grab.app, but there is a simple hack to do it...