**Is our universe a simulation?**

So this is kinda scary. And amazing. And complicated.

Mathematician Edward Frenkel writes in the New York Times that one fanciful possibility that explains why mathematics seems to permeate our universe is that we live in a computer simulation based on the laws of mathematics - not in what we commonly take to be the real world.

According to this theses, some highly advanced computer programmer of the future has devised a simulation and we are unknowingly part of it.

Thus when we discover a mathematical truth, we are simply discovering aspects of the code that the programmer used.

This may strike you as very unlikely, but physicists have been creating their own computer simulations of the forces of nature for years, just on much smaller scale. They use a three-dimensional grid to model a little chunk of the universe; then they run the program to see what happens.

"Oxford philosopher Nick Bostrom has argued that we are more likely to be in such a simulation than not.

"If such simulations are possible in theory, he reasons, then eventually humans will create them - presumably many of them. If this is so, in time there will be many more simulated worlds than nonsimulated ones. Statistically speaking, therefore, we are more likely to be living in a simulated world than the real one."

Yikes.

Is there any way to empirically test this hypothesis? Well, surprisingly, yes.

In a recent paper, “Constraints on the Universe as a Numerical Simulation”, the physicists Silas R. Beane, Zohreh Davoudi and Martin J. Savage outline a possible method for detecting that our world is actually a computer simulation (PDF).

Savage and his colleagues assume that any future simulators would use some of the same techniques current scientists use to run simulations, with the same constraints.

The future simulators, Savage indicated, would map their universe on a mathematical lattice or grid, consisting of points and lines. But computer simulations generate slight but distinctive anomalies - certain kinds of asymmetries and they suggest that a closer look at cosmic rays may reveal similar asymmetries.

If so, this would indicate that we might - just might - all be in someone else’s computer simulation…

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