I Thought He Came With You is Robert Ellison’s blog about software, marketing, politics, photography and time lapse.

Life, Non-locality and the Simulation Hypothesis

Conway's Game of Life, Recently

Conway's Game of Life is a cellular automaton where simple rules lead to surprisingly complex behavior. You can even build a Turing Machine in it. Life consists of a grid of cells which are either alive or dead. For each generation a cell flips from dead to alive if it has three alive neighbors. If a cell is alive and has two or three neighbors then it survives to the next generation, otherwise if dies. When programming a non-infinite Life game it's common to wrap the logic at the extent of the grid - so the some 'neighbors' of the cells at the very top are the cells at the very bottom and so on.

Imagine that you discover such a system and try to figure out the physics of it.

After observation of a sample of cells you'd figure out the rules that govern the life and death of most cells. You'd also figure out a speed of 'light' for the system - information can only travel one cell per generation. The state of cells further away have no influence. You've got a kind of classical physics of the Game of Life.

Further study would throw up a puzzle though. Cells at the extremes of the system are influenced by cells at the other extreme. In some cases the speed of 'light' is violated - you now have a non-local physics in the mix. At this point you might fix the problem with geometry - maybe the grid is actually wrapped around a torus (even though you're looking at a rectangular grid). This makes the system logically consistent again but it's wrong - the non-local behavior occurs because you're trying to analyze a simulation.

In quantum physics observing the state of a property on one particle in a pair of entangled particles will instantly effect the observation of that property on the other particle, no matter the distance between them. This is Einstein's spooky action at a distance. It seems like it can't possibly be true, but has been demonstrated repeatedly (and quite spectacularly using starlight to select which property to measure).

There are many different interpretations of how to understand quantum physics. But as you might expect from physicists these concern themselves with a physical universe (or multiverse depending on the flavor). It's possible though that non-locality (and the apparant quantized nature of our reality) is trying to tell us something else. Non-local effects are entirely consistent with a reality that is being generated frame by frame, just like a souped up Game of Life.

(Read the full simulation hypothesis series: Part 1: Can I move to a Better Simulation Please?, Part 2: Have we Already Proved that the Simulation Hypothesis is False?, Part 3: Life, Non-locality and the Simulation Hypothesis.)

Have we Already Proved that the Simulation Hypothesis is False?

Updated on Wednesday, August 14, 2019

Despite a spate of press to the contrary there is no proof that the simulation hypothesis is false. It just might be too hard for a classical computer in our universe.

A couple of years ago a spate of articles claimed that there was proof that the simulation hypothesis was false, like Sorry, Elon. Physicists Say We Definitely Aren’t Living in a Computer Simulation in Futurism:

"A recent study by theoretical physicists from Oxford University in the U.K., which was published in the journal Scientific Advances just last week, definitively confirms that life and reality aren’t products of a computer simulation."

Strong statement. This is because they determined that running a simulation of a small quantum system was intractable:

"To store information about a couple hundred electrons, they noted, one needs a computer memory that requires more atoms than what’s available in the universe."

This might have something to say about what we can simulate on a classical computer in our universe, but it has no bearing on if our universe is itself simulated. If it is we have no idea what kind of computer is doing the simulating, nor what the physical laws are of the universe where that computer is running, nor even how many atoms it has at its disposal.

It's okay Elon, you still might be on to something.

(Read the full simulation hypothesis series: Part 1: Can I move to a Better Simulation Please?, Part 2: Have we Already Proved that the Simulation Hypothesis is False?, Part 3: Life, Non-locality and the Simulation Hypothesis.)

Can I move to a Better Simulation Please?

Updated on Wednesday, August 14, 2019

A risk free simulation

In the New York Times last weekend Preston Greene has an op-ed piece on the simulation hypothesis where he argues that we shouldn't check, because:

"If we were to prove that we live inside a simulation, this could cause our creators to terminate the simulation — to destroy our world."

But let's back up. To start with he trots out Bostrom:

"In 2003, the philosopher Nick Bostrom made an ingenious argument that we might be living in a computer simulation created by a more advanced civilization."

Am I living in a simulated universe where I am the only person to have ever consumed any science fiction, or spent late nights discussing the nature of the universe in a bad simulation of a kitchen? For some reason Nick Bostrom is now almost universally credited with the simulation hypothesis. Every article on the topic seems to starts with this revelation. In 2003! Like right after he finished watching The Matrix Revolutions. Have no newspaper editors ever read any Philip K. Dick? Descartes? This is not a new idea, and Bostrom's ancestor simulations are a rather tortured special case of a much wider set of possibilities.

And then:

"Professor Smoot estimates that the ratio of simulated to real people might be as high as 1012 to 1."

Sounds specific. It could be 1016 though. Or 7. Not really subject to numerical analysis at our current level of knowledge (which Greene would not increase).

And given that we don't know this invalidates the whole point of the article:

"In much the same way, as I argue in a forthcoming paper in the journal Erkenntnis, if our universe has been created by an advanced civilization for research purposes, then it is reasonable to assume that it is crucial to the researchers that we don’t find out that we’re in a simulation."

That's one possibility, sure. Reasonable to assume? No. Equally possible is that the researchers are trying to find universes that figure out that they are simulated. They keep the ones that manage it within 13.773 billion years or so and discard the others.

I think it's even more likely that simulated universes are a commodity and the number running as screen savers vastly outnumbers those used for serious research projects. Our fate depends on whether the entity that installed us is having a three martini lunch or heading back after two.

(Read the full simulation hypothesis series: Part 1: Can I move to a Better Simulation Please?, Part 2: Have we Already Proved that the Simulation Hypothesis is False?, Part 3: Life, Non-locality and the Simulation Hypothesis.)