I've been reading on the many-worlds interpretation (http://en.wikipedia.org/wiki/Many-worlds_interpretation). Hypothetically speaking, how can the many-worlds interpretation be used in a game? Or should the theory be scrapped when planning a game due to being too difficult to use?

Off the top of my head:

You could create a mystery game where players jump from one universe to another and have to figure out or use the differences -- sometimes small, sometimes very large -- to proceed with the game.

You could create a game where players are actually given the ability to fracture a single reality into two, and then proceed to play either in all of them at once, or in a single chosen reality. See the "time shock" mechanic (and follow-up, "time shock tactics") from "300 mechanics" for one possible design.

Being sent to an alternate reality could be used as a plot device for an interesting storyline.

I think for reasons of practicality and so that players could actually follow what was happening in your game you would generally need to stick to a relatively small number of alternative universes rather than infinite possibilities.

Parallel universes and/or time streams have been used in several good adventure games and RPGs, and would be good in more of these i the future. :)

I have often thought about this myself and my personal take on it would be time travel.

Consider playing through a game, reaching some climactic point, realizing you are in a spot of trouble, being able to 'jump' back to a previous point and alter the flow of events, the key part being that you could make it better or worse. You would have to limit this ability some how.

A good example of this is http://www.achrongame.com/site/

They have a full RTS game with this ability allowing you and your opponent to battle it out across the four dimensions.

If you could create some form of fast procedural world development system you could jump through time altering events such as sparking a war between two countries to change the face of the world. It has enormous potential as a gameplay mechanic but will be very difficult to implement in a fair manner.

I have often thought about this myself and my personal take on it would be time travel.

Consider playing through a game, reaching some climactic point, realizing you are in a spot of trouble, being able to 'jump' back to a previous point and alter the flow of events, the key part being that you could make it better or worse. You would have to limit this ability some how.

I was under the impression Time Travel would be harder if the Many-Worlds theory was correct. Because you would have to specify what universe to be in unless it's set by default.

If you're speaking literally and not philosophically, then there's no application for this in a typical game. The interpretation is a way to understand quantum physics, at an atomic scale. Most games are at such a scale where simple Newtonian physics are sufficient and there is no need for the complications of einsteinian physics or quantum physics...

If you were to literally incorporate many worlds, then whenever there is a probabilistic even in your game, you need to clone the game world n-times, once for each possible outcome, and then continue the simulation for each branch. After just a small number of events, you've got billions of copies of your game running, with no one true version of events, which doesn't sound useful!

If you were to literally incorporate many worlds, then whenever there is a probabilistic even in your game, you need to clone the game world n-times, once for each possible outcome, and then continue the simulation for each branch. After just a small number of events, you've got billions of copies of your game running, with no one true version of events, which doesn't sound useful!

This isn't necessarily true as you could store the events as they happen, a very primitive example is actually the ability to undo changes made when editing a document (and to a certain extent, redoing them also. You've probably noticed that once you go back, make a change, you can't redo any undos from the previous branch). So long as you can convert all the important things into functions of time so you can get their values when not sitting on a key-event, you could essentially store the world based on the events that happen. As to which world is the 'true' version, one possible solution is that you can only jump back in time, which means you can edit something in the past which changes the future but once you have jumped back in time, you would then have to proceed naturally again. You could potentially include the option to simulate forwards in time without considering how the user might influence the world which would allow for travel forwards in time but that could be potentially tricky (i.e. what if the player gets killed?). Thinking about it, a save point in a game is actually very similar to what I am describing, but that's just one way of looking at it.

I was under the impression Time Travel would be harder if the Many-Worlds theory was correct. Because you would have to specify what universe to be in unless it's set by default.

It really depends on how you want to implement it into a game, personally I think it has amazing potential, but it does for the most part only seem reasonable in single-player or co-op modes, although the aforementioned Achron game seems to have done a nice job of using it.

I've exploited this in a game recently. It was an incredibly boring risk-like war game where I used the built-in save feature, played the turn, recorded the outcome, and then went back in time and changed the outcome to my benefit.

... use it.

..how can the many-worlds interpretation be used in a game?

Long ago, I played a space game where the save files constituted a tree arrangement of progression. If the player reached a death or found themselves insoluble, they could go back up the tree and explore alternative choices from any save node.

..how can the many-worlds interpretation be used in a game?

Long ago, I played a space game where the save files constituted a tree arrangement of progression. If the player reached a death or found themselves insoluble, they could go back up the tree and explore alternative choices from any save node.

Wyrm, would this game be anything like the first game in the "Colony Wars" series? From the description it's close to what you said, if you failed a mission (without dying) you'd be pushed into an even harder one you're not very likely to succeed in, representing the desperate tactics required to keep a foothold, until you reached an ending.