lunes, 20 de noviembre de 2006

The Universe as a Video Game

As a result from a couple of strange events, I've got an interest on being able to explain my own personal vision or understanding of the Universe. Trying to find a good analogy, and after considering nondeterministic finite state machines, I thought that a video game would be something much more common and easier to understand. :-P

Please note, this is only an analogy. It does not mean that I really believe that our Universe works exactly like a video game. But the analogy will be very useful to define several of the concepts which we will probably like to discuss about.

Good, let's start by imagining a game like World of Warcraft, where lots of people from different parts of the world (our world) can connect in order to play. Each person takes the form of a character inside the game and controls it (using a joystick, keyboard or whatever) in order to move it around while exploring the world (of Warcraft) inside the game.

The characters inside the game can, in some way or another, interact with their environment (pick up objects, hit enemies, etc.) but they do not have an absolute control over it. For example, most likely, it is not possible to walk ‘upwards’ over the sky where there is nothing, make objects appear out of the void, disintegrate all of your enemies just by thinking about it, or dramatically modify —suddenly and without any explanation— the map of the world.

Actually I do not know very well the details of the game, so an apology in advance if it turns out that some of this things are really possible in WoW. Anyway, I hope that the general idea is clear: the world is somehow controlled by a set of rules, and the characters in the game are free to do lots of things (go and rescue a princess, randomly run without any direction and jump from a precipice, gather a group of friends and start dancing), but always constrained by the rules of the world.

From this toy example we can already define some interesting concepts. For example, the Universe is the world created inside the game (with all its trees, mountains, and characters randomly running without direction; in something like StarCraft it might also include solar systems, other planets, etc.) and physics are the rules that govern the Universe (the code or program of the game).

The body of a living being is an object or entity inside the game that can be manipulated by an external player outside the game. The soul is precisely this player, which holds a controller on its hands and takes decisions over the actions that its body performs inside the game. This is how the living beings can interact with the Universe, but always limited by the laws of physics.

This also divides my model in two parts: the physical plane, namely the Universe where the bodies live, and the spiritual plane, whatever it is where the souls live. Finally God, the Creator, is whoever has written or developed the game. In our (toy) example, Blizzard is God.

Some people might not agree with my definitions (I've heard, for instance, some definitions of God quite different to mine) but, for practical purposes in the rest of this post, the important keywords (Universe, God, etc.) mean whatever I said that they mean (in other words, if you don't like my “labels”, change them for other words that bother you less and keep on reading).

We will now see what happens when we try to use this analogy in order to describe our own reality. We also have an Universe which seems to be constrained by some rules of physics. I also want to clarify that, in this case, by physics I mean whatever is effectively programmable and deterministic (i.e. always if this happens, then this other thing also happens).

The nondeterministic components of the system is what I call the spiritual plane. The actions of the souls are the ones which are not completely determined by the laws of physics (they might be limited or influenced by the laws of physics, but not determined by them). If it weren't by this spirutal plane —and the actions of the souls in it— the physical plane would be completely, totally and absolutely predictable.

I don't know if you have noticed but, until now, I haven't said much things. And I do not plan to say much more either. The only thing that I've been doing is to give several definitions that will be useful in order to make us questions so that, when we think or discuss about them, we are all more or less imagining the same thing.

A lot if interesting questions seem to be in the relation between the physical and the spiritual planes. Science (medicine for example) seems to indicate that a good deal of the processing that happens in our brain is happening within the physical plane. How much of our “will” is programmed within the physical world? Is there really a nondeterministic component (i.e. souls) or are we completely programmed to do what we do? What is the subconscious, and which role does it play within this model (is it a physical or a spiritual thing)?

Other questions, of course, are raised around the figure of God. The fundamental question, does God exist?, is reduced in this setting to ask: Did someone created the Universe? or did it just suddenly appeared, without the need of a Creator? or maybe it has existed forever, without never having a beginning?

And if we suppose that God does exist, then: Is God also a player? does he also has a controller and is playing among us in this Universe? Can God modify the rules of the game (the physics) while the game is running? Can God stop or restart the game? Has this actually happened?

Another of the questions, which I am particularly interested in, is: How much of the science of physics (i.e. our models that we have created trying to explain how the Universe works) is similar to the real physics (i.e. how things really work)?

And, of course, the most transcendental question that we all have asked to ourselves. When you die, does it really says “Game Over”?

4 comentarios:

Rochy dijo...

And there is something you don't mention in your theory: why are we playing this game? I don't think it is just for fun ;-), otherwise we would be able to leave and enter it anytime (or probably our souls were bored and decided to play =p).
Blizzard is God! I thought it was Page, or Bill Gates ;-)

Anónimo dijo...

When you ask:
"How much of our “will” is programmed within the physical world?"
I think this question implies an adventure into the very essence of humanity and will lead to the most incredible brain or neural system research work in the future (I hope a near one, for sure).

juan antonio dijo...

Hi Rochy!

Of course there are many more interesting questions you can ask. And “why are we playing this game?” is definitively one of the most interesting ones.

I don't want to give away my own personal answers, for now, but I'll just say that I've always loved playing fun games. :-)

And anon., I also agree with you that trying to answer the question about how much our own “will” is programmed will lead to very interesting and exciting research; and not only about humanity, but of living things in general. (note I tried to avoid the word “humans” in my original post)

Joachim dijo...

Juan has asked some interesting questions here, which are based on his very structured presentation of a possible reality. Well, lets see if I can contribute some answers to his work, or at least, point out some caveats.

First of all, I think it is necessary to concretise Juan's definition of the term "body". While I especially liked this vague noun, it seems that at least Mr Anonymous immediately took it as being a synonym for "human". I find that a rather strong constraint. It immediately implies that, for example, animals have no souls under Juan's definition of the concepts "body" and "soul". Also -- even though a bit far fetched -- some alien race might be very different to us humans, so the term "humanity" and its associated ideals might not apply, but still they could posses souls as well. Hence, I would adapt a rather minimalistic view and refer to the tiny bits and pieces of matter that found our universe as "bodies".

How can nuclei, photons, or all this other weird chunks of matter and energy posses a soul? Well, take any elementary object I just mentioned, then you would rather propose that these "things" do not have a soul. However, if you have plenty of them sticking together and forming a human being, it is suddenly said that this lump of matter does posses a soul. Of course, what we really is the coordinated interaction of all bits and pieces it is made of. As such, I propose that the soul we perceive and associate with the whole of our body, can in fact be broken down into smaller pieces and assigned to all basic physical objects that constitute the body. The latter claim may sound like blasphemy to one or the other, but keep in mind that it does not take away the souls from humans. Instead, I am just a bit generous what a soul can be, so that I can work more easily with Juan's definition of a soul.

In fact, when working on the microscopic level of the universe, the behaviour of elementary particles is not deterministic at all. In other words, for example, predicting the movement of a particle can be impossible. Exactly in this situation, one may think of an external player in Juan's spiritual plane, who is interacting with the particle and making it go in any direction he/she/it/they wants to. This behaviour is called non-deterministic by Juan.

Now, lets get rid of the external player. Instead, I assume that the whole universe is just a program in a computer, which is modelling the interaction of elementary particles. When I say "computer", I really mean a Turing-machine, which is an idealised concept of a computer with an infinite amount of memory. Luckily, Turing-machines can be non-deterministic. Since the machine can be non-deterministic, the whole universe, and thus the behaviour of elementary particles, is still non-deterministic. Hence, we may still pretend there is an external player that tells the machine which choice to take, while we really cannot comprehend why a particular choice was made and simply refer to the choosing mechanism as non-deterministic.

The crux: non-deterministic Turing-machines are equivalent to deterministic Turing-machines.

In other words, instead of the universe being modelled by a non-deterministic Turing-machine, it could as well be a deterministic Turing-machine -- and yet, particle movement would appear non-deterministic to us observers.

So, is one's life pre-determined and thus meaningless? Well, it could be pre-determined, but that does not imply it is meaningless, boring, or predictable. Especially when it comes to predictability, I have to highlight a nice feature of Turing-machines: they are undecidable. Well, formally correct I should rephrase it as "their halting problem is undecidable". I do not want to explain this in detail, but it roughly means that if I want to now if some time in the future "XYZ" will be true, it is not determinable. In other words, even though the universe could be deterministic, no one can predict "what will happen in the future".

As I tried to say, a deterministic universe does not mean that we are mere actors in an perfectly directed movie. We know how life feels, we do make choices, we enjoy ourselves. We also have to admit scientific progress, but sometimes we think it is rather constraining, when it really does not do anything to our daily life. Unfortunately, for those who belief in religion, it makes the concept of a soul obsolete.



Final Note: The restriction I applied upon the universe, i.e. to be a Turing-machine, is the most pessimistic view. There is the idea of hyper-computation, which is a more powerful approach than Turing-machines. As such, the universe could also be a hyper-computing device. However, my point still stands, as even the most pessimistic view leaves us with enough degrees of freedom to be individuals as I have pointed out.