orbits to the properties of atoms. Math was used to predict the existence of the planet

Neptune, radio waves and the Higgs Boson. Some think it means nothing profound, or

that math is simply something we've made up to be useful. Others think it means that

there's something fundamentally mathematical about nature. The most extreme possibility

is that our universe is completely mathematical, in the sense that it has no properties except

mathematical properties. 

But at first glance, our universe doesn't seem very mathematical at all. A sheep has

properties such as cuteness and fluffiness — not mathematical properties. Yet we know

that this sheep - and everything else in our universe — is ultimately made of elementary

particles such as electrons and quarks. And what properties does an electron have? Smell? Color?

Texture? No, only properties like -1, ½ and 1! We physicists call these properties electric charge,

spin and lepton number, but the electron doesn't care what we call them: the fundamental properties

that an electron has are just numbers, mathematical properties. As far as we know, all elementary

particles, the building blocks of everything around, are purely mathematical objects in the sense

that they don't have any properties except for mathematical properties. The same goes

for the space that these particles are in - for example, it has the property 3, the number

of dimensions. If space is mathematical and everything in space is also mathematical,

then the idea that everything is mathematical doesn't sound as crazy anymore. 

Quantum mechanics and string theory introduce even more mathematical structures, with nerdy

names like Hilbert space, linear operators and Calabi-Yau manifolds. We physicists

still haven't found any properties of nature that we can prove are non-mathematical, which

is why some of us - including me - think that perhaps there just isn't anything else out

there, other than math. And that thought makes me one positively awestruck

mathematical object.