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Alert: you may be living in a simulated universe

By Geraint Lewis

Are our lives real or is the universe just an enormous computer simulation?

The full text of this article can be purchased from Informit.

As a cosmologist, I often carry around a universe or two in my pocket. Not entire, infinitely large universes, but maybe a few billion light years or so across. Enough to be interesting.

Of course, these are not “real” universes; rather they are universes I have simulated on a computer.

The basic idea of simulating a universe is quite simple. You need “initial conditions” which, for me, is the state of the universe just after the Big Bang.

To this, you add the laws of physics, such as: how gravity pulls on mass, how gas flows into galaxies, and how stars are born, live and die.

You press “go”, and then sit back as the computer calculates all of the complex interactions, and evolves the universe over cosmic time. The video below gives a good introduction:

A wonderful description by Andrew Pontzen on how astronomers synthesize and study their very own galaxies and universes.

What’s more fun is playing “Master of the Universe”, and messing about with the laws of physics, such as changing the properties of gravity, or how black holes swallow matter. Waiting to see the outcome of these mutated universes...

The full text of this article can be purchased from Informit.

Geraint Lewis is Professor of Astrophysics at the University of Sydney. This article was originally published at The Conversation.