Level 4 mutiverse

[BrainMan]

From: http://www.geocities.com/haripaudel/Parallel_Universes.htm

 

Is there a copy of you reading this article? A person who is not you but who lives on a planet called Earth, with misty mountains, fertile fields and sprawling cities, in a solar system with eight other planets? The life of this person has been identical to yours in every respect. But perhaps he or she now decides to put down this article without finishing it, while you read on.

The idea of such an alter ego seems strange and implausible, but it looks as if we will just have to live with it, because it is supported by astronomical observations. The simplest and most popular cosmological model today predicts that you have a twin in a galaxy about 10 to the 1028 meters from here. This distance is so large that it is beyond astronomical, but that does not make your doppelgänger any less real. The estimate is derived from elementary probability and does not even assume speculative modern physics, merely that space is infinite (or at least sufficiently large) in size and almost uniformly filled with matter, as observations indicate. In infinite space, even the most unlikely events must take place somewhere. There are infinitely many other inhabited planets, including not just one but infinitely many that have people with the same appearance, name and memories as you, who play out every possible permutation of your life choices.

 

Max Tegmark goes on to describe level 1, 2 and 3 multiverses, and then gives his own novel idea: the level 4 multiverse. Basically, he states that the universe we are in is a particular mathematical structure, and every possible mathematical structure that can exist, does exist. That is, there are different universes with different laws of physics... and infinitely many of them.

 

 

Sounds kinda cool... What do you think?

[Crash]

Limitless possibilities,

where do they exist?

 

[edit] on further thinking it MUST be a conciousness within a person

[AntiMagicMan]

I read this article when it was originally published in Scientific American. You've got to admit the theory is quite nice, but I suppose it is not scientific because we could never test the hypothesis that there are alternate universes.

[Crash]

Itll just get logged away in the "cant be tested or dissapproved" section of science

[BrainMan]

According to Tegmark, it is testable. It is a matter of looking at all possible structures, and determining if our universe is probable. Actually, it gets a bit more odd... we need to look at all possible structures, and of these, look at all possible structures capable of producing self-aware substructures. Then we look at, among these, the probability of a self-aware substructure observing exactly what we observe in our own universe.

[Crash]

what do you mean, "is our universe possible"? sounds just plain Bizarro

And it dosen't sound to me like any normal human is actually capable of examining ALL possible structures

BTW after even further consideration they cant (in anyway) be a conciouness within a person, so i go back to my original question where do they exist, materially or err....well for lack of a better word non materially?

[BrainMan]

The question is if our universe is probable[/i], not if it is possible. [Although if, based upon this, our universe turned out to be "immpossible", that would simply mean that our universe is non-mathematical which means that theory would be wrong.

 

Where are what? The "material" we see would be, "in reality", mathematical structures- or reflections of such from a frog's eye view.

[Crash]

Where do the alternate universes exist? because there would be alot of them!, How would you define if our universe was probable? Mathmatically?

Seems pretty probable to me, because where here!

[BrainMan]

An assumption made at the start, for this theory, is that space is infinite. With infinite space, anything that can happen, will happen- no matter how improbable. But there will be distributions- some universes will be more probable than others. Odds are we live in a probable universe- for universes with self-aware substructures. If, according to our observations, we turn out to live in an improbable universe, then the thoery is not supported.

 

So: Where? In the infinity of space [there would be infinitely many of every possible universe...]. How? By comparing our universe (our observations) with the probability distributions of possible universes to see if ours is probable. Yes, mathematically.

 

Just because we are here does not mean we live in a universe that would be probable given this theory.

[Crash]

Nothing is infinite........everything is finite

Your/this idea seems inprobable

[BrainMan]

Nothing is infinite........everything is finite

 

You don't know that.