That the world we experience is really just a simulation is not a new idea by any means, but it seems to have garnered a lot of attention in recent years, so I cannot resist taking a crack at it too. This is not the "virtual reality" idea of our existence being false or fed to us by some outside agency. That would be the "brain in a vat" concept of reality, similar to the false-reality concept famously explored in The Matrix movie trilogy.
Rather, in this post I want to explore the idea that ALL of what we experience as reality, including our selves and our minds, is one huge simulation in a giant computer as suggested by Neil deGrasse Tyson, and Elon Musk among others. For simplicity here, and without much loss of generality, I will name the entity doing the simulation as "God", and suppose that the platform for the simulation is simply his mind, so that no supercomputer or software are required. These designations do not limit the discussion since any other simulator would effectively be God from our perspective, and any simulation platform will do for discussion purposes.
However, thinking that we exist only in the mind of God puts a new, and quite literal spin on, "In him we live and move and have our being" (Acts 17:28, but first written by Epimenides in the 7th century BC). Aside from that, it allows us to assume a benevolent simulation; God is not trying to fool us, his simulation is simply our reality. If reality is essentially the context in which we exist, then a simulated context would be just as real to us as a "real" world. But the religious terminology also clearly puts us in the realm of "speculative theology", if you will, and opens up all sorts of interesting interpretations and connections that are fun to explore. Having done a little computer simulation work myself, I can see numerous possibilities.
First of all, it makes creation of the Universe seem more manageable somehow, at least from our perspective. Genesis 1: "and God said, let there be...", seems more objective if God is setting up his simulation in his own mind. When you do a computer simulation, you specify the initial conditions, the range of the simulation in time and space (or other variables), define the rules for the simulation, and then press the start button, allowing the simulation to proceed, usually via a series of small steps in time. You then observe what happens, either to model a real system or scenario, to better understand what is happening, as in an electronic circuit, or to predict the future of whatever is being simulated, as in climate models for weather forecasting.
In our simulated world, the initial state could refer to the cosmological conditions at the start of the Big Bang when the universe came into existence. Those would be the energy and matter densities, and rules about the expansion of space-time. Depending how far back to the supposed singularity you want to begin, this could be a quark/gluon soup at gigakelvin temperature levels, or mere protons, electrons and neutrons in a uniform photon bath. In any case, God could specify these initial conditions anyway he wished, thereby easily accounting for the flatness of the present Universe and explaining the horizon problem in cosmology, without invoking some mysterious inflation theory.
The "rules" for the world simulation would, of course, be the laws of physics, which govern how the particles and energy exist and interact, starting with quantum mechanics, expanded to include the four known forces of nature (strong nuclear, weak nuclear, electromagnetic, and gravity), along with their physical constants (c, e, G, h, k, etc.). Whether God's simulation uses the same "laws of physics" we have developed over the centuries to model our reality, or some other algorithmic formulations, I will leave to the reader to ponder.
For those conversant with modern cosmology, you will see that the start of this simulation neatly explains the fine tuning problem apparent in the Universe. God's purpose presumably included complex beings like us, so his initial conditions and rules would have to allow for our "existence" within the simulation. No untestable and unparsimonious "multiverse" is needed to "explain" away the obvious fine tuning in ours. Then again, perhaps God had done a number of previous simulations in order to zero in on the one that would yield what he wanted. That would depend on your view of God; whether he is all knowing and could get it right the first time without problems, or a Being who likes to explore and play with his ideas to expand his creations for his own good pleasure (or amusement).
As another "benefit", the simulation hypothesis neatly takes care of the temporal dimension in our reality. By convention, simulations begin at time t = 0 and proceed in a forward direction. There is no "prior time", the simulation simply begins to exist at t = 0. Thus, in this scenario any speculation about what happened "before the big bang" is meaningless. Moreover, the simulation timeline need not consist of equal step sizes. In computer simulations, the time step is sometimes adjusted to speed up or slow down the simulation for more precision during fast events, or less during boring times between slow events. The same could, in principle, be true of God's simulation. The first microsecond of the Big Bang would need fine time steps to capture events as currently theorized by cosmologists, while between supernova events, bigger time steps could be used to track the expansion of the universe or the aging of stars.
This concept of variable time steps only makes sense in the context of the simulator's time frame. From our perspective inside the simulation, a second is a second; whether God has divided it into femto or atto-second steps, we would not be aware of it. If I am simulating some physical phenomenon, each simulated time step will take a certain number of "clock cycles"; that is, a certain amount of my time in the real world, which will depend on the simulation software and the hardware platform (e.g. clock speed). Thus the simulated passage of time and the simulator's clock are quite different; God's own timeline (within eternity, somehow) need not be the same as ours, here inside the simulation. Just as the scientist watching his simulation is not stuck in its time line, so God is not constrained to ours, "With the Lord a day is like a thousand years, and a thousand years are like a day" (2 Peter 3:8, Psalm 90:4). That represents a range of more than 100 billion in relative rates for passage of time!
This idea has further possibilities that are intriguing, or perhaps disturbing, depending on your viewpoint. As in a computer simulation, God could stop his simulation at any time, effectively suspending time (and our reality), for as long as he wishes, perhaps to examine our thoughts (prayers?) in detail, as data in some memory buffer in his own mind. When playing a computer game, which is essentially one type of simulation, we often save our game to return later, after supper, or a good night's sleep. In principle, God could do the same with us. What's more, if our game avatar dies in the game, we will likely return to a previously saved game to restart it at that point, hoping to do something different this time to avoid being "killed", based on what we learned the last time. Indeed we may have to do this many times to proceed through the game. The characters in the game are "unaware" that they have played this scene "before" in your timeline, that they have killed you or perhaps "died" themselves. The game is simply reset to an earlier point in "time" and restarted as if the events leading to your avatar's "death" never occurred.
Does God do the same? Is it possible somehow that in God's timeline he has "replayed" numerous events numerous times, back tracking to a previous "save game" point in order to change the outcome of the current one? His preferred result may include your salvation, or my not being killed in a traffic accident. Of course, with multiple characters in his simulation (many billions over the millennia), it may not be possible, even in principle, to have the "best" possible outcome for all of them. Thus, if God wants to invest us with meaningful "free will" (whatever that means in a simulation context), even he will not be able to prevent bad things happening to some people. Perhaps he chooses some favourites for his own inscrutable reasons to pour out his blessings on? That begins to sound like predestination as in Calvinism! I did say some would find this disturbing. I hope these speculations do not get me into trouble!
In any computer simulation, the owner or operator can interrupt the timeline (suspend the simulation) and then go into the memory registers and adjust any of the parameters he wishes to change, in order to tweak the simulation along whatever lines he wants. Similarly, God could presumably be free to do the same in his Universe simulation. Early on, perhaps tweaking the laws of physics to allow stars and planets to exist, then adding rules when needed for chemistry, life, and eventually, us. This evokes the Intelligent Design theory, where the designer (AKA, God) is "allowed" to be active in his creation, to pursue his own ends.
In the context of a simulated reality, intelligent design (ID) theory also solves the origin of life problem, via the injection of complex biochemical information to get cellular life started on Earth. Evolution too can easily occur with the occasional injection of new genetic information into existing simulated life forms at suitable time points. In that way, God can be seen as "tinkering" or "playing" in his creation (the simulation) for his good pleasure, as it progresses toward his goal. That goal might well have been to, "make man in our image" (Genesis 1:26), which is to say, create a spiritual being, within his (simulated) material Universe, capable of interacting with him.
From our vantage point, inside the simulation, any noticeable but sudden change due to God's intervention, or parameter tweaking would appear inexplicable, which is to say, miraculous. Miracles therefore, may simply be God's occasional adjustments to our ongoing simulation. He would have gotten all the long-term settings correct long ago (on cosmological and geological time scales), and now limits himself to directing or "fine tuning" historical and social directions at cultural and human time scales. Any such interventions would then primarily be associated with his purposes for our souls or spirits, as are most recorded miracles throughout history.
Our human spirits might exist in God's simulation as bundles of algorithmic interaction protocols, potential abilities and preferences, heuristic behavioural guides (and other buzz-word gobbledegook), associated with each new human person. There is considerable evidence that our minds are not entirely materialistic, nor simply algorithmic in our (simulated?) material context, so perhaps our spiritual aspects exist as an added layer of simulation, connected into God's own mind somehow, and external to the material Universe simulation, but able to interact with it. This, of course, raises questions about "free will", which I will leave the reader to decide for himself. It also accommodates a variety of religious understandings, such as cosmic consciousness, and god-within-us views.
To stretch the religious interpretations further, when we die, here in the simulation, God might simply "up load" the spiritual aspects of those he likes, into a better "simulation"; perhaps one called "heaven", thereby providing for life after death. Alternatively, such human spiritual bundles could be revamped or reset and then re-injected into the ongoing Universe simulation as new people (reincarnation anyone?). Other spirits that God does not want to continue developing or using immediately might get stored for future use, discarded, or even relegated to "hell" in an entirely different simulation - one not as much fun. On the other hand, perhaps those destined to hell are not fully conscious spirits, but only metaphysical "zombies" that appear to the rest of us as human, but have no actual souls? In that case, in a sort of universalism, no true simulated spirit would actually end up in hell. There's lots of room here for idle speculation and religious syncretism!
Continuing to explore the possibilities of this simulated Universe yields some additional, but perhaps troubling suggestions. One obvious interpretation is that this scenario is just a simple form of pantheism: everything is God and God is in everything. Philosophically, this is a form of monism (everything is one essence), which may not be palatable for some. Another disturbing possibility is that the simulation actually began just yesterday in our timeline, with all of our reality and memories merely the initial conditions chosen for us. If those were set up carefully, there would be no way for us to know that our past was just a complex illusion. Then again, perhaps I am the only "real" mind in the simulation and all of my reality, including you and the rest of the world are just data inputs to my processor. One may wish to speculate about God's motive for doing that.
One final religious speculation is regarding the person of Jesus. There are now several science fiction motifs about humans entering into virtual realities, or their own simulations, so thinking of God immersing himself into his Universe simulation as a true human person, while still retaining his Godliness (Emmanuel - God with us), is not too difficult to envisage. God would then be simultaneously external to the simulation (the "Father" in his eternal timeline), while operating as a human inside our timeline - "the only begotten Son". With some further consideration, we might then think of the Holy Spirit as God's way of speaking to our spirits and dealing with our prayers. By means of this approach, our theological speculations have invoked the Trinity: three divine persons in one Godhead.
Although such speculations are interesting and entertaining, I do not actually believe them. While existing as a detailed simulation in God's mind may be indistinguishable from a truly material Universe with real flesh and blood people, it somehow reduces God to merely a clever and powerful simulator; perhaps even a trickster playing a complex computer game for his own amusement. I prefer the Christian belief in a loving God who created a stable material reality with creatures to inhabit it, in order to interact with his spiritual image bearers for all of eternity.