### You're Shaped Like A Donut

Really. Your topological shape is the same as a donut. Granted, you have what our British friends call "dangly bits" hanging off here and there, and—to be accurate—a few extra holes too. But basically you're a lump with a hole through the middle.

There's a hole that starts at your mouth and ends at your, well...other end. A donut has a hole through it too. And while a cup has that funny container part on one side, it still has just one hole through it.

Letters of the alphabet can be classified by their topology too. a, b,d, e,o, p, and q are letters with one hole; c, f, h, k, l, m, n, r, s, t, u, v, w, x, y, and are letters without a hole; and a i and j are letters consisting of two pieces. Depending on what font you use g may either be a one holer or the only letter that's a two holer, depending on whether or not the tail is closed.

So? What we're talking about here is topology, a branch of mathematics and an extension of geometry, sometimes referred to as “rubber sheet geometry.” Two objects are considered the same if they can be continuously deformed into one another by bending, twisting, stretching, and shrinking, but not tearing or gluing. Some geometry problems depend not on the exact shape of the objects involved, but rather on the way they are put together. For example, a square and a circle are similar in that they separate a geometric plane into two parts, the part inside and the part outside the figure.

As a kid, our co-conspirator here, Paul, discovered the topology of animals for himself. He'd heard that geese would quickly pass a piece of pork fat through their system. Always the skeptic, he tied a piece of fat to a string, and took it out back to the pen where his Mom kept a flock of geese. Sure 'nuff, before long he had the whole flock on a string. Mathematics in everyday life.

TH

There's a hole that starts at your mouth and ends at your, well...other end. A donut has a hole through it too. And while a cup has that funny container part on one side, it still has just one hole through it.

Letters of the alphabet can be classified by their topology too. a, b,d, e,o, p, and q are letters with one hole; c, f, h, k, l, m, n, r, s, t, u, v, w, x, y, and are letters without a hole; and a i and j are letters consisting of two pieces. Depending on what font you use g may either be a one holer or the only letter that's a two holer, depending on whether or not the tail is closed.

So? What we're talking about here is topology, a branch of mathematics and an extension of geometry, sometimes referred to as “rubber sheet geometry.” Two objects are considered the same if they can be continuously deformed into one another by bending, twisting, stretching, and shrinking, but not tearing or gluing. Some geometry problems depend not on the exact shape of the objects involved, but rather on the way they are put together. For example, a square and a circle are similar in that they separate a geometric plane into two parts, the part inside and the part outside the figure.

As a kid, our co-conspirator here, Paul, discovered the topology of animals for himself. He'd heard that geese would quickly pass a piece of pork fat through their system. Always the skeptic, he tied a piece of fat to a string, and took it out back to the pen where his Mom kept a flock of geese. Sure 'nuff, before long he had the whole flock on a string. Mathematics in everyday life.

TH

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