Three things to think about before applying to enrol in Philosophy of the Cosmos:

Are you interested in cosmology? And especially in things even cutting-edge cosmologists disagree about? Well, ok, who isn't? This one is probably easy.

Are you happy with the assessment? Note that you have to be happy writing essays.

The course is open to students in all degree programs, not just science students. But we'll be mentioning a lot of maths in this course. We'll be starting from scratch, so you don't have to actually know much maths. And we won't be asking you to do any calculations. But you do have to be interested in maths.

If either you already understand the following factlets

**or**you're sure you'd enjoy getting a handle on them, then you're ready for the maths in this course.

It takes light about a second to get from the Earth to the Moon. Here it is in real time (with the Earth and the Moon drawn to scale):

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(picture from http://en.wikipedia.org/wiki/Moon, 1/5/2013)
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It takes light just under 14 billion years to get from the furthest galaxies we can see to us ... but the current estimate is that they're 46 billion light-years away. The reason those numbers are different is that space is thought to have expanded faster than the speed of light.

(If you're thinking that that contradicts Einstein's theory of Special Relativity, then bonus points to you, and you're right, it does.)

The geometry of spacetime describes how a test body moves in the absence of any forces. We don't actually know the large-scale geometry of the universe, but we need to find out what it is if we're going to understand cosmology.

The Schrödinger equation

is a continuous differential equation that describes a wave, where *t* is time, H is a mathematical description of how an experiment's set up, *i* and *h* are constants, and ψ is the state of the system as it evolves over time.

You don't have to understand what the parts of the equation are or how to use it, but you mustn't freak out when you see it, and you have to be interested in the fact that it describes a wave.

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