# Dear Dirichlet, Issue 09

Coffee, Brexit and badgers are among the topics of discussion in this issue’s Dear Dirichlet advice column

Moonlighting agony uncle Professor Dirichlet answers your personal problems. Want the prof’s help? Send your problems to deardirichlet@chalkdustmagazine.com.

### Dear Dirichlet,

My husband and I have found ourselves in a long-distance relationship. His company offered him a large promotion if he moved to Canada for six months, but it seems now that the position will require more time. I’m not sure that I want to move out there with him, or that I could be happy knowing he had to move back here. Conversation with the time difference is hard as well. Any tips?

— Getting tensor, Four Oaks

Dirichlet says:

This has been a common theme among correspondents to my column, but thankfully technology offers some options. Part of your problem is that you are measuring time and distance using the flat spacetime metric,
$\mathrm{d}s^2 = -c^2 \mathrm{d}t^2 + \mathrm{d}x^2 + \mathrm{d}y^2 + \mathrm{d}z^2.$
Instead, get out your iPad and try the flat FaceTime metric. In my experience, this works better for special relatives.

### Dear Dirichlet,

I’m an undergraduate and often work in the department common room. It has desks, books and a coffee machine, which is great — except I hate the smell of coffee! I try to open the windows but get frosty looks from the others. Reckon I can get them to switch to another drink?

— Sick Paul, Five Ways

Dirichlet says:

Clearly the students have failed the tea-test. You could try getting in early and setting up a tea distribution. No promises though, it might just be that you and the others are too significantly different from each other. In which case, consider testing another location.

### Dear Dirichlet,

Did you know that it is ILLEGAL to sell triangles whose angles don’t add up to 180°???? When I was growing up, our triangles had all sorts of interior angle sums and no-one got hurt. Now we’re being told that HEALTH & SAFETY laws mean that parallel lines can NEVER meet! Time for the fractal generation to grow up!

Dirichlet says:

I see you look forward to leaving EUclidean geometry. But if you enjoy being obtuse, you could have just summed the Brexterior angles, for Brexample, instead of resulting to Brextrema. If you want me to Brexplicitly Brexpress what I Brexpect to come from this Brexercise, I fear that by Brextemporising, we are Brexposing ourselves to Brextinction. To Brexplain using predicate logic,

BRE          Brexponential decay.

### Dear Dirichlet,

I am the concerned parent of a 13-year-old son. As a boy, he was always fun and adventurous, if not the sharpest tool in the box. But he seems to be going through a phase where he leaves the house for large periods of time, not always returning until quite late. It’s putting a large strain on the household: do you think he will be done with this soon?

— Thirteen, THIRTEEN?!, Seven Sisters

Dirichlet says:

I am pleased to hear that your son is a bit thick and that he often doesn’t come back. As any rheologist will tell you, if he’s elastic, the stress you experience will be proportional to the strain; but if he’s viscous, the stress will be proportional to the strain rate. As long as you keep the strain at a constant level, therefore, you will feel considerably more relaxed.

### Dear Dirichlet,

Any ideas for Halloween costumes? I’m getting it sorted in advance this year.

— David S Pumpkins, Leighton Buzzard

Dirichlet says:

Captain Hooke’s law. Franken-spline’s monster. A scary badger.

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