Many people have considered this idea that the real world around us is, in fact, simulated. Most have probably simply gone on with their lives afterwards.
The idea that we may actually be living inside, sort of, a ‘computer’ simulation is hardly new. Over two thousand years ago, Plato wrote about a comparable idea in his story about a cave: the prisoners in the cave do not see reality, but only the shadows of reality.
Before the Matrix, StarTrek had a version of simulated reality in the holodeck. Descartes considered the idea and, more recently, Nick Bostrom had some creative thoughts about it too. He used a formula, so his thoughts may even be scientific.
The idea has been around for a while. However, the scientific community has not spent very much attention to it. Why would it anyway? It seems useless: if we really are living inside a simulation, what would be knowable about the higher-reality? Is the simulated environment not much more interesting to explore than the ‘real’ one? Can any theories around reality ever be falsified? Soon you will be accused of hocus-pocus if you talk about it.
In my quest for reality, I have to consider it though. And even take it seriously. To explore the idea, I would tend to fall back on the methodology I described in an earlier article, off-course. Practically this means to first just go look what we know (i.e. the guru has to travel to the edge of the earth).
So, I’ll start with some clues as to a simulated reality and see if I can build a theory around those.
As scientific experiment probes deeper and deeper into smaller and smaller particles, the facts we are collecting seem to get weirder.
It all started with the observation that the speed of light seems independent of the speed of the observer. It does not matter how fast you go, the speed of a light beam will always be the same: It will always be about 300.000km/s faster than you.
After that we also observed that a beam of particles can interfere to show a wave-like interference pattern (so it must be a wave, right?), but can also travel a billion km in a straight line (so it must be a particle, right?).
What’s more, the particle can be in two places at the same time, or can, for example, spin up and down at the same time. But only as long as unobserved…
As soon as we observe, the particle has one location and/or one spin direction… But what exactly ‘observation’ means or who the observer can be, we do not really know.
Many theories explain these observations, but so far there is no generally accepted one yet. Some of the theories have great success in mathematics: the maths are so complex, precise and controllable that they are, at least, very useful and also by many people taken to be true.
The scientific theories in the past century since we started discovering weird facts have developed a lot. Amanda Gefter does a nice investigation into what the nature of reality might be in her book: Trespassing on Einstein’s lawn.
After investigating a lot of theories, she is concluding that we are really all in our own frame of reference. She is searching for unchangeable, absolute reality that we all share. Considering for example the speed of light, absolute positions etc. She almost reaches the conclusion that nothing is absolute.
The obvious conclusion she does not draw in her book is this: we could each literally be in our own frame of reference. We could be in a simulation of our own where we could be the observer and everything is relative to ourselves.
There are a few clues around that this simulation idea may actually be true. Let’s start with some positive evidence. (in the sense of Popper) This is what I could think of, if you know of any others, let me know!
1. The Quantum: Planck constant etc.
First clue: the world appears quantized. There has been no real explanation for this observed fact yet.
There appears to be a unit for energy, a unit for mass, a unit for distance. So, observations appear to show that the world is not continuous: you cannot always look for smaller constituent parts of things. Energy exists only in whole multiples of the smallest energy unit.
This is very similar to what happens in a digital computer: numbers in a computer have a unit (one) that cannot be subdivided. Bits are either 0 or 1. This facilitates computing. If computers were analogue, they would be a lot more difficult to construct. Possibly even impossible to construct at anything that gets close to the power of digital computers.
If I were to create a simulation, I would make it quantized. I would maybe even make it digital.
2. Just-in-time calculations (Schrödinger’s probability-function collapse)
Second clue: In quantum mechanics, a particle can almost be in more places at the same time. ‘Almost’, because there is a probability that a particle is at a given location at any one time.
When observed, the ‘probability function collapses’: the particle is observed at a location (100% certainty) and not at another. Until that time of observation, the particle behaves as a probability-distribution.
To me, as a computer programmer, this looks very much like a “just-in-time calculation”. I know, this is computer-speak!
“Just-in-time” basically means that any calculation is postponed until the results are actually needed. If you do not need the results in your program, you do not execute the calculation.
If your program calculates a simulation, you do not really need to calculate the trajectory of an atom 10 billion light-years away behind some moon: it has negligible influence on the observer.
You could just keep track of the average temperature of a large region of space and how that might influence the simulated world of the observer. If the observer actually travelled to the distant spot, only then would you have to do more detailed calculations. In this way, you can greatly limit the number of calculations and save time.
It appears from observation that particles are only calculated as a probability distribution. Basically, a location has a chance of containing a particular particle. In maths-speak (which is different from computer-speak) they call this a ‘field’. This is the calculation the other way round: the calculation is done for each location, not for each particle.
In this way, you only have to calculate the contents, and only in vague terms of chances, of each location (it is quantized, remember?). If you could do this roughly from the information in the directly surrounding locations, this means that the calculations can be much more speedy.
If a particle is observed, it is not difficult to then randomly place the particle given the probabilities of where it might be.
Calculating the trajectories of all individual particles of all space would be an immense job. This would probably be impractical. The just-in-time calculations of only placing particles when they are being observed is much easier. Basically, you keep probability-scores for each location in a space (field) surrounding the observer and track only particles that have been observed. The smaller this field, the fewer calculations have to be performed.
Considering how much around me I can observe (it is mostly limited to the room I am in and then mostly forward-looking too), the number of calculations can be reduced drastically and to very realistic proportions. Even with today’s computer power.
3. Observer dependency
That brings me to the third clue based on the same observation of the collapsed probability-function: observer dependency. It appears actual particle location/speed is dependent on an observer. It appears possible to create a setup where the physical world is different based on whether it is being observed or not. (i.e. Schrödings cat is dead AND alive until observed). Quantum mechanics is partly based on this observation-dependency.
Well… but this is inconvenient. Anyone skeptical to quantum Mechanics could ask questions like: who/what is this observer exactly? Just me? Any person? Can animals be observers? Can computers? What about rocks?
When exactly is an experiment ‘observed’? When the event happens or when the light beam describing the event hits my eye?
So, how can we account for this in a theoretical model of how the world works? There are many theories that offer explanations.
One theory would be to say that the ‘real-world’ actually splits into two separate universes, one for each outcome (1. cat=dead and 2. cat=alive), maybe into other dimensions or such. I would note first that these infinite parallel universes take up infinite resources (place?) etc. A bit like the infinite turtle problem, really. It seems very impractical. Is this falsifiable, by the way?
If you think about this parallel-universe idea, and the universes could not communicate with each other, then the only universe that really matters to me is mine. My universe is private.
If we were inside a simulation, the conclusion would be simpler. The observer would be: me!
I really would have a very special role in reality…
4. Physics laws seem to have to satisfy unreal mathematics
A lot of phenomena we have observed in particle physics can now be predicted or calculated. We know the math to do this. Unfortunately, in a lot of cases we do not have an underlying real-world model for this math.
A simple example is the use of ‘force’ in classical mechanics: we can calculate the relationship between a mass in a particular circumstance (like rolling of a hill or circling the sun) and it’s speed. However, we need an unreal property in the formula’s to do this: let’s call it a ‘force’ (there is also a force in StarWars: ‘use the force, Luke’). If we use the formulas of Newton and we introduce this force-quantity, we can actually calculate the trajectories of the planets pretty precisely. It is so precise that most people believe the formulas actually are ‘true’ and thus reflect reality in some way. The ‘force’ must really exist then, right?
Since Newton, we have greatly enhanced the preciseness of the formulas. Einstein improved on them, but also had to allow for unexplained phenomena (or should I call them assumptions?). For example: Space curves when a mass is present (why?), approximately 300000km/sec is the maximum speed (why?), gravity is effectively the same as acceleration (why?).
Quantum mechanics is amazingly precise in what we are able to calculate. But here too, we have no concept of what the formulas might actually mean for reality. How can a particle have any features that are described by complex numbers? Complex numbers are just meant to help out in intermediate calculations and are very unreal, right?
It sometimes feels like particles move in a particular way just to satisfy mathematics.
Some people suggest that the ‘lowest level’ of reality -the smallest parts of what everything is made of- is actually mathematics itself. It is abstract (for example Max Tegmark, even though he also adds parallel universes to his theories).
This is an interesting idea! You could take it to the next step and argue that mathematics is abstract and only exists in the mind of the observer… If mathematics comes out of the brain of the observer, reality out of mathematics and the brain out of reality… The circle would be complete then…
If reality was a simulation, mathematics could, in a real practical sense, indeed be the basis of everything.
5. Perfect cosmological constants
Many people have observed (and really, this is the same argument as the previous one) that there are a lot of ‘constants’ in physics. These constants have been ‘measured’ (or inferred from measurements) to great precision. It has been noted that if these constants were slightly different from what we observe around us, the universe as it is (and life) would likely not be possible. So how can these constants be so perfect for our universe? At first this seems a huge coincidence.
Max Tegmark offers as explanation that all possible constant-constellations (and also mathematical-formula constellations) are actually in existence in different parallel universes. The one we are in (the one with live, consciousness and such) obviously has the right set for us, then. The other universes may carry no life (or even collapse entirely). So, it is not a coincidence we find ourselves in a universe with perfect constants. This is called: survivor-bias.
In a simulation the constants could just be set by the simulator.
6. Gauge forces
The sixth clue may be in the calculation of forces. Einstein basically held that a force is the result of a mathematical equation, that is necessary to consolidate different reference frames of moving observers.
Einstein’s special relativity: Two observers could move relative to each other, but still observe the same, absolute speed for the same beam of light. To explain this, you could say that space ‘contracts’ at speed. This is effectively a mathematical correction to ensure the formulas match observed facts. By proposing that the observers each think they are stationary and the meter is shorter for the faster observer, both observers measure the same lightspeed. His detailed and complex formulas for this have withstood testing.
Sometimes, the mathematical consolidation becomes quite difficult. Einstein later proposed that space is bend, depending on the masses present in it. This would be the same effect as acceleration. The mathematical ‘corrections’ needed to consolidate the views of two observers would result in a movement of the observers, which they would experience as a force. (if I move without a direct cause, I call it a force…)
There is something shared between the observers that looks absolute: the light-speed. There is also something not shared between the observers: their own frames of reference (or ‘universes’?). In order to make the shared observation the same in both universes, you would therefore need a mathematical correction: this results in what we call a gauge force. Just like complex numbers, this force would be a mathematical construct but does not really exist… or does it?
From current scientific thinking, it appears that all ‘forces’ that we know of could be (or will soon be) explained as gauge forces.
Suppose I have a (private) simulation and somebody else has their own simulation…
…and if we had a shared absolute reference point (i.e. the speed of light),
…and the two simulations would meet,
à then mine and/or the other simulation would have to be ‘corrected’, along Einstein’s formulas.
Do I then experience gravity because somebody else is observing me? Yes, maybe!
7. Workings at spooky distance
A final clue I want to mention is in something Einstein also objected to in quantum mechanics: The possibility of instantaneous cause-and-effects over unlimited distance: a.k.a. ‘workings at spooky distance’. This violates not only Einstein’s maximum speed, but also most people’s common sense.
One of Einstein’s objections against quantum mechanics was that information could travel faster than the speed of light. If this was possible, that would be counter-evidence against his own special relativity theory. One of the two had to be wrong. Einstein thought his theory was right.
He offered a thought experiment: two particles are entangled at source and fly away from each other. We make sure that there is an observed quantum property (say: total spin or even the location) in the original state. We wait for a while and then measure one of the particles. We now know the spin of the other particle, even before any information from it could have traveled to us (with the maximum speed of light). The fact that we know the spin of the distant particle means that it actually has this spin: it’s probability-function has collapsed. We have finished manipulating a distant particle before we could have sent anything to it. Unfortunately for Einstein, experiment appears to confirm this is actually possible and thus appears to validate quantum mechanics.
I do not know if she thought of this first, but at the end of her book, Amanda Gefter offers a nice explanation to make things right. She proposes that the distant particle may be manipulated, but to find out if it was, you would need to observe it as well. In order to do this, you would need to receive some information which could only travel with the speed of light. My probability-function for this particle only collapses when the information reaches me.
So, in a way, there is nothing wrong as long as you consider only your own frame-of-reference: There is nothing wrong if my probability functions are my own. In my private universe as it were.
This must be a strong clue as to the whole thing being a simulation. Why does she not draw the conclusion in her book?
Looking at the previous clues, they seem to overlap a bit. The just-in-time calculations (clue 2) appear similar to the observer dependency (clue 3). The influence of mathematics (clue 4) is also apparent in the cosmological constants (clue 5) and gauge forces (clue 6).
One theory that could explain the observations is that reality is actually private: each person has their own. A simulation could be a practical implementation. It exists only privately to you yourself.
I believe a simulation could be a much simpler explanation of reality than observer dependency (Stockholm model) or parallel universes. The simulation idea does not offer a complete explanation of the origins of reality: it does not answer the question of the origin of the higher-reality that made the simulation. Max Tegmark’s mathematical universe gets much closer to a complete explanation.
Occam’s razor however would then make me favor this. It also seems a very practical solution to the questions raised by quantum mechanical observations. If it is so, it is so.
The nature of reality
If we are in a simulation, we are a simulation. The brain -that whitish mass inside our heads- is then simulated, not ‘real’. However: “I think therefore I am.” still holds true!
Brain processes are intimately linked to our personality. This is obvious from various cases of people with brain damage etc. Change the brain and you change (or even lose) personality. Simulated or not.
However, on top of this, there could also be some sort of computer that is calculating us and our simulated reality. ‘Observed’ in private reality could then be seen as ‘calculated’. You could argue that this calculator is you (and even constitutes your consciousness?).
Me and my reality is then really the same, one thing: I am reality.
The nature of a higher reality
The reality that is calculating our simulated environment is unknown. It will also be very difficult to find out anything about it. It could be similar to the simulated environment, but does not have to be at all.
It could for example be predictable, have no weird quantum effects and may have an obvious origin.
The mechanics of the simulation
As a computer programmer, I could come up with a model of how a simulation could work. There are again a few clues that provide some good starting points. In the interest of not making this article too long, I may write a completely speculative follow-up article about this.
Can it be tested? Is the theory falsifiable? More so than other theories about the nature of reality?