# Valentine’s For That Special Someone

Nothing says “I love you” like a non-orientable surface. Instead of just making the usual Möbius strips for Valentine’s
Day though, this year, consider making interlocking Möbius based Hearts!

Instructions for making the topologically fun Hearts can be found from Matt Parker or on the 360 Blog.

Topologically, the Möbius strip can be defined as [0,1] × [0,1] with its top and bottom sides identified under the relation (x, 0) ~ (1 - x, 1) for 0 = x = 1

The Möbius strip is a two-dimensional compact manifold with a single boundary. Cutting the Möbius strip along the center line creates one long strip with two full twists in it, and two edges.

While the topology of a Möbius strip sliced down the centre line isn’t as interesting (as it’s no
longer a Möbius strip then), the gesture still seems sound. The Möbius based hearts are a nice

There is also the Sierpinski themed option, with instructions available on the 360 Blog as well.

Based off of the Sierpinski triangle, the pop-up Sierpinski heart card is a romantic homage to the famous fractal.

The basic idea behind the creation of the pop-up heart card is a simple application of the standard algorithm for obtaining arbitrarily close approximations to the Sierpinski triangle. Unfortunately, in the paper-heart case, the difficulties of folding come into play.

When done properly, the number of hearts (triangles) after the nth iteration is 3^n.

While it’s not the most careful application of the fractal generating algorithm, it’s still pretty cute. Although, since the (Lebesgue) area of a Sierpinski triangle is zero, the romantic gesture might be a little lacking.

# Loveable Equations

The Wolfram|Alpha blog did a nice post for this Valentine’s Day featuring some very loveable equations. Instead of paper, try generating some your favourite
shapes with the equation grapher of your choice.

There are five standard one dimensional curves (two dimensional graphs) for Valentine's Day: the (rotated) Cardioid, the First Heart Curve, the Second
Heart Curve, the Third Heart Curve, and the Fourth Heart Curve.

Of course, there are always the standard two Valentine’s Day Surfaces to choose from:

 Taubin's Heart Or the Bonne Projection

If all else fails, candy is still a valid fall back option.