Does the concept of infinite parallel universes justify absurdities?

[bland]

I know this has been discussed ad infinitum (pun intended) however I have recently been informed by Max Tegmark's book Our Mathematical Universe, that apparently the multiverse concept is becoming mainstream. In fact he mentioned at a recent quantum conference that a show of hands revealed no votes for the Copenhagen interpretation.

I don't want to get into a discussion on parallel universes but rather an aspect of it that really bugs me. Maybe I'm just not fully understanding the concept of 'infinity' but this is my concern...

BTW I'll first point out that Tegmark talks about 4 separate levels of multiiverses, the lowest level simply being universes that are outside of our observable horizon but still technically a part of our universe. Anyway this is my worry whatever level of multiverse we are talking about.

The general idea in all of them are that in an infinite quantity of universes *everything* is going to happen eventually, the reason is that there is infinite time and so no matter how unlikely anything *will* happen.

But to my thinking the very same infinity can be used to basically say the opposite. Because we just come up with an infinite amount of trivial changes, or an infinite amount of absurdity. For example if we have an infinitely long truly random number then it is supposed to be possible that somewhere in that sequence we can find one hundred zeros in a row. Nay not one hundred but one million. Yes given enough time we can expect a series of one million zeros in a row that will in fact still be truly randomly generated.

This is plainly idiotic because we can then say even the more unlikely trillion zeros in a row is possible, *in principle* but let's not stop there we can have a nonillion and so on. In the same way we can do that with the multiple universe thing that reckons everything will happen. If you say 'yes' in principle there can be a nonillion series of zeros I will say that 'you'll simply be waiting an infinite amount of time before that occurs', in other words the reasons for it occurring are the same reasons for it not occurring.

So why is it that infinite parallel universes or multiverses are becoming more accepted and then used to justify absurdities?

Sorry if this doesn't make sense.

 

[PeroK]

There are two aspects to this:

1) The mathematics of infinite sets. And, in particular, mathematical probability theory.

2) How to apply this to a spatially infinite universe or to an infinite set of universes. Especially regarding a probabilitistic model.

The mathematics is clear: if an event has a finite (and constant) probability of occurring in any trial, then the probability of its occurring in $n$ trials tends to 1 (certainty) as $n$ tends to infinity.

You could, for example, apply this to tossing a coin. If you look for $10$ heads in a row, then the probability is $1/1024$. If you repeat this experiment about $1,000$ times, then you have a good chance of getting $10$ heads in a row. And, if you repeat the experiment a million times, then you are almost certain to get $10$ heads in a row many times.

And, if you look for 1 million heads in a row, then likewise after a very large number of experiments you will almost certainly have got your one million in a row. According to mathematical probability theory, at least.

However, in practical terms, it may be impossible to carry out that experiment in our universe sufficient times to ever even have a remote chance of getting one million heads in a row. So, you can start to question whether that mathematical property of large numbers has any physical significance.

Note that you cannot "toss a coin an infinite number of times". Even theoretically, you can only ever toss a coin a finite number of times.

If you imagine that our universe is spatially infinite and has an infinite number of "Earths", each with a coin tosser, then you could argue that there will be one million heads in a row somewhere in the sequence.

But, again, practically there is no way to set up such an experiment.

If, finally, you say that nature is doing something randomly on each planet - meaning effectively nature can have repeated an experiment an infinite number of times - then it's not clear whether that is a valid argument or not.

In summary, I think you do need to take care in extrapolating probability theory to an infinite universe (or infinite set of universes).

 

[DrChinese]

1. The general idea in all of them are that in an infinite quantity of universes *everything* is going to happen eventually, the reason is that there is infinite time and so no matter how unlikely anything *will* happen.
...
2. So why is it that infinite parallel universes or multiverses are becoming more accepted and then used to justify absurdities?

The mathematics is clear: if an event has a finite (and constant) probability of occurring in any trial, then the probability of its occurring in $n$ trials tends to 1 (certainty) as $n$ tends to infinity.

1. It is not necessary to assume that ALL things happen in some universes. There could be plenty of hypothetical events that occur in no universes. For example, there might not be any universes in which I am DrGreek instead of DrChinese. Is there a universe in which I killed President Kennedy? There must be a path in which that outcome is a possibility from some earlier possible state. (Even though the number of possible outcomes is incredibly large.)

2. The number of multiverses could be very large, and possibly infinite. I don't think either of those lead to absurdities by themselves, it is more the way it is described in lay terms that would seem absurd.

 

[Demystifier]

In fact he mentioned at a recent quantum conference that a show of hands revealed no votes for the Copenhagen interpretation.

Where did he mentioned it? Reference or link please!

 

[DrClaude]

I know this has been discussed ad infinitum (pun intended) however I have recently been informed by Max Tegmark's book Our Mathematical Universe, that apparently the multiverse concept is becoming mainstream. In fact he mentioned at a recent quantum conference that a show of hands revealed no votes for the Copenhagen interpretation.

These are two disjointed statements. Not accepting the Copenhagen interpretation doesn't mean embracing the multiverse.