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Is the whole universe just a simulation? – Moumita B., age 13, Dhaka, Bangladesh
How do you know anything is real? Some things you can see directly, like your fingers. Other things, like your chin, you need a mirror or a camera to see. Other things can’t be seen, but you believe in them because a parent or a teacher told you, or you read it in a book.
As a physicist, I use sensitive scientific instruments and complicated math to try to figure out what’s real and what’s not. But none of these sources of information is entirely reliable: Scientific measurements can be wrong, my calculations can have errors, even your eyes can deceive you, like the dress that broke the internet because nobody could agree on what colors it was.
Because every source of information – even your teachers – can trick you some of the time, some people have always wondered whether we can ever trust any information.
If you can’t trust anything, are you sure you’re awake? Thousands of years ago, Chinese philosopher Zhuangzi dreamed he was a butterfly and realized that he might actually be a butterfly dreaming he was a human. Plato wondered whether all we see could just be shadows of true objects. Maybe the world we live in our whole lives inside isn’t the real one, maybe it’s more like a big video game, or the movie “The Matrix.”
Are we living in a very sophisticated version of Minecraft?
Tofli IV/Wikimedia Commons, CC BY-SA
The simulation hypothesis
The simulation hypothesis is a modern attempt to use logic and observations about technology to finally answer these questions and prove that we’re probably living in something like a giant video game. Twenty years ago, a philosopher named Nick Bostrom made such an argument based on the fact that video games, virtual reality and artificial intelligence were improving rapidly. That trend has continued, so that today people can jump into immersive virtual reality or talk to seemingly conscious artificial beings.
Bostrom projected these technological trends into the future and imagined a world in which we’d be able to realistically simulate trillions of human beings. He also suggested that if someone could create a simulation of you that seemed just like you from the outside, it would feel just like you inside, with all of your thoughts and feelings.
Suppose that’s right. Suppose that sometime in, say, the 31st century, humanity will be able to simulate whatever they want. Some of them will probably be fans of the 21st century and will run many different simulations of our world so that they can learn about us, or just be amused.
Here’s Bostrom’s shocking logical argument: If the 21st century planet Earth only ever existed one time, but it will…
