This question is very popular nowadays, and I will try my best to answer it from my philosophical perspective. Now first of all, why did this question became so popular now, despite metaphysical philosophies have been debating the fabric of reality for thousands of year.
Could it be because computers are now predominant in our society? So much that people think of themselves to be insignificant, like being inside a simulation like a computer program? It could certainly be so.
I think this question is promoted because people today are very collectivists, and have a slave mentality. People today think of themselves as some insignificant ants roaming around in the world. This reinforces collectivism, and as a result now people think of themselves as being only computer programs, mere shadows cast by some programmer (be that God or Multiverse, or whatever).
This started in the 19th century when people have discovered the vastness of the Universe, and Creationism started falling. But when the Computer came out, people started drawing analogies, because it seems like the Universe looks just like an advanced Computer Simulation.
I mean we have "Universal Laws" an analogy to a Source Code, and we have Speed of Light an analogy to Rendering Speed, and we also have Planck Length, which is like the basic length that is analogous to a Pixel or in 3D to a Voxel, and indeed Quantum Physicists have started exploring the idea of a Voxelized World.
So it certainly looks like the theory has some basis, combine that with the inferiority complex of the modern human, and the general leftist culture that we live in today, and we have this theory. It should be suspicious though that leftists promote it, but that is not the point, let's just examine it as it is.
Is it True?
Well that I cannot tell, because in philosophy there is no absolute truth, however in my philosophy there is only 1 truth though, so I would say that no, this theory is absurd. The universe is not a simulation.
Besides this is just a high-tech version of the Brain in a Jar argument that has been haunting philosophy for ages.
So whether you are just a brain in a jar that is manipulated by demons, or whether you are a unicorn that is hallucinating of himself of being a human, or whether you are a computer simulation on God's laptop, is equally absurd, and you can't tell which one is more true, because there is no way of being certain of any of that. There is no proof for either, and there isn't even a method that you can establish that would tell you how to prove it.
The metaphysical reality can be anything, because there is no way to observe it, because we are inside it, and we need to use it, in order to observe it, which is impossible to do, it's a logical trap.
- People put concepts in logical boxes, that is how your mind work, for example:
An apple is a fruit. A fruit is a plant. A plant is a living being. A living being is a part of the Universe. A Universe (if there are more) is a part of Reality.
- But when it comes to Reality, you cannot put it inside another box, because there is no box outside of it. It is what it is, and all tools that you use to describe it, is inside it, therefore you cannot know nor possibly describe how it is:
Reality is Reality. - and that's all you know about it.
So when you are saying that "Reality is a Computer Simulation" is absurd, because a "Computer" is part of "Reality", it can't be outside of it. And when you say the "Universe is a Computer Simulation" (supposing that there are more universes which are not, whatever that would mean) is also absurd, because you can't go outside the universe to see what it is, you can only work inside it.
So therefore my conclusion is that the only thing that you know for sure is what you can observe. Or in other words, my metaphysical theory is that reality is subjective, and there is no objective reality whatsoever. And I have detailed my basic philosophy in my series:
- https://steemit.com/philosophy/@profitgenerator/secrets-of-the-universe-part-4-rejecting-platonism
- https://steemit.com/philosophy/@profitgenerator/secrets-of-the-universe-part-3
- https://steemit.com/philosophy/@profitgenerator/secrets-of-the-universe-part-2
- https://steemit.com/philosophy/@profitgenerator/secrets-of-the-universe-part-1
Conclusion
- So if you believe it's true, then it is, and you will live your life thinking that you are just an insignificant human, that is floating on the ocean of eternity like a debris on the ocean.
- And if you believe it's false, then maybe you can live a much better life, because you will at least focus on your own life, as an individual, and rescue yourself from the inferiority complex.
- But regardless of which one you believe to be true, the only thing certain is, that you exist, and even if your sensory perceptions are cheating you, the experience itself will always be true. It is all subjective.
Upvote, ReSteem & 
Nicely put. I enjoyed your article
This part was particularly succinct.
"because we are inside it, and we need to use it, in order to observe it, which is impossible to do, it's a logical trap"
Therefore the only possible way to know anything outside of the reality we found ourselves in, is if it were "revealed"
... and that opens up a whole new can of worms...
No it actually closes the can of worms. It is actually the fundamental answer that shows that subjectivity is all that it counts.
Because if you try to think about abstract objective theories, every single time the question becomes:
So eventually it always boils down to subjective experience. Doesn't matter how far your wonder out in the realm of philosophy, it always comes back to you, you are at the center of it always.
This is why I rejected objectivism.
I suppose 'our reality' could be a simulation in a computer in the 'real' universe, but it seems unlikely. The computing power required would be unimaginable if every being in the simulation were to be experiencing it. I guess we do simulate some simple worlds in games and elsewhere these days, so maybe we are in an immense Sims game.
It's something like some religions that think our lives are pre-ordained. I know philosophers argue about whether we have free will, but I'm happy to imagine that I do and live accordingly.
I'm certainly no expert on philosophy.
It could certainly be, but the universe can also be:
... or other absurd things
I mean you get the idea. You can come up with any explanation or description of the universe because all of them will be equally absurd. Nobody knows, and there is no way for anybody to know. Besides your senses can always betray you, so the question is meaningless.
And since yoru senses could betray you, the only reality you know is what you experience, regardless of content. That is why my basic metaphysical theory is that reality is subjective, and that there are no objects.
Read my other articles to get the idea:
I will do one on Free Will vs Determinism too in the near future.
Duck typing. If it looks like a duck, quacks like a duck, you can call it something else, but it is a duck. When quantum simulations are perfected, they won't be simulations, they will be indistinguishable, even in theory from the literal thing. That is basically what this says: http://rspa.royalsocietypublishing.org/content/royprsa/400/1818/97.full.pdf
So if A and B are indistinguishable, what information is added by changing the label? It seems to me to add another tool that may be used to think about it. For instance, considering temporal mechanics now has an additional framework to apply that ties it to informatics.
Because there is no testable difference, why feel differently? We don't know many implementation details about the universe, and when we find the next particle, there is no rational reason to feel any differently. Why should this implementation detail be any different? A creator can still exist - after all, who are we to tell them how to conduct their grand design?