# Dear Dirichlet Valentine’s Day special

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

Need a Dear Dirichlet Valentine’s Day card? We’ve got you covered.

### Dear Dirichlet,

I feel like my fiancé and I are continually going round in circles. Despite living together, the distance from our workplaces means that we’re shattered by the time we get home and, as a product, we get cross. I don’t want to set rigid rules for our careers, but we keep saying that we’re going to find jobs in a new town, and six months later we’re still in the same position. Have you fixed this problem for anybody?

— Uptown girl, White bread world

Dirichlet says:

The two of you need to take a moment to stop pulling against each other and just torque. You can’t expect a happy equilibrium all the time, but as long as you don’t force it, you should be able to change your angrier momentum and become a happy couple.

### Dear Dirichlet,

But, soft! What light through yonder window breaks? It is the east, and Juliet is the sun. But, like the sun, I only see her on high, shining from her balcony, many braccia above my head. How I long to be able to run up and see her, but all I can do is bite my thumb and cry out from the ground. It’s also often a bit windy and this makes communication difficult. Can you help?

— R. Montague, Verona

Dirichlet says:

Fear not, fortune’s fool. Under the envious moon, simply apply the skew matrix $$\begin{pmatrix}1 & 0 & \tan\alpha \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{pmatrix}$$to young Juliet’s house, and you will find that the imposing front bows down before you. For ease of calculation, I recommend $\alpha = \pi/4$, but if you prefer a shallower ascent, $\alpha=\pi/3$ or $5\pi/12$ will smell as sweet.

### Dear Dirichlet,

I’ve been dating my girlfriend for three weeks now and I am in blissful freefall. Everything started so fast but it just feels so right. I’m sure she’s the one but how can I know that the relationship will go the distance?

— Ken O’Mattock, somewhere along the M1

Dirichlet says:
$$v^2 = u^2 + 2as.$$

Solve for $s$ where $v=0$, $u = \text{so fast}$ and $a = -9.8\,\mathrm{ms}^{-2}$. Many years ago I did this calculation, and the present Mrs Dirichlet and I have been together 20 years.

### Dear Dirichlet,

I’m really up the creek this time. I’ve forgotten to buy my wife a Valentine’s Day present and now it’s too late to order off eBay. Surely she’ll know if I nip up to the petrol station. Many years ago I remember taking a couple of strips of paper, rotating one of the ends and then taping them into interlocking twisted loops. If I remember correctly, once I did that, I could cut along them in a special way to make some romantic interlocking hearts. Do you have the details so I can save my marriage?

— Non-orientable, Newport (South Wales)

Dirichlet says:

Möbius strips should be band.

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