Imagine if you could look at a snowflake at the South Pole and determine the size and the climate of all of Antarctica. Or study a randomly selected tree in the Amazon rain forest and, from that one tree--be it rare or common, narrow or wide, young or old--deduce characteristics of the forest as a whole. Or, what if, by looking at one galaxy among the hundred billion or so in the observable universe, one could say something substantial about the universe as a whole? A recent paper, whose lead authors include a cosmologist, a galaxy-formation expert, and an undergraduate named Jupiter (who did the initial work), suggests that this may be the case. The result at first seemed "crazy" to the paper's authors.

The existential question that we should be asking ourselves, is are we living in a simulated universe? The idea that we are living in a simulated reality may seem unconventional and irrational to the general public, but it is a belief shared by many of the brightest minds of our time including Neil deGrasse Tyson, Ray Kurzweil and Elon Musk. Elon Musk famously asked the question'What's outside the simulation?' in a podcast with Lex Fridman a research scientist at MIT. To understand how we could be living in a simulation, one needs to explore the simulation hypothesis or simulation theory which proposes that all of reality, including the Earth and the universe, is in fact an artificial simulation. While the idea dates back as far as the 17th-century and was initially proposed by philosopher René Descartes, the idea started to gain mainstream interest when Professor Nick Bostrom of Oxford University, wrote a seminal paper in 2003 titled "Are you Living in a Computer Simulation?" Nick Bostrom has since doubled down on his claims and uses probabilistic analysis to prove his point.

When Anders Sandberg was a kid in the 1980s, he enjoyed making simulations on his Sinclair ZX81, mocking up mini solar systems. Later, he graduated to designing artificial neural networks that use learning algorithms inspired by the brain. "Some people relax by watching television. I program simulations while listening to philosophy lectures," Sandberg chuckles. One day back in 1999, he recalls, he deleted a copy of a neural network on his computer and got a "tinge of bad conscience." He couldn't help worrying: "Have I just killed a little creation?"