The strongest limit on the number of possible universes is the human ability to distinguish between different universes. Posted on 10/18/2009 4:06:14 AM PDT by LibWhacker
The strongest limit on the number of possible universes is the human ability to distinguish between different universes.
(PhysOrg.com) -- Over the past few decades, the idea that our universe could be one of many alternate universes within a giant multiverse has grown from a sci-fi fantasy into a legitimate theoretical possibility. Several theories of physics and astronomy have hypothesized the existence of a multiverse made of many parallel universes. One obvious question that arises, then, is exactly how many of these parallel universes might there be.
In a new study, Stanford physicists Andrei Linde and Vitaly Vanchurin have calculated the number of all possible universes, coming up with an answer of 10^10^16. If that number sounds large, the scientists explain that it would have been even more humongous, except that we observers are limited in our ability to distinguish more universes; otherwise, there could be as many as 10^10^10^7 universes.
To work these numbers out, Linde and Vanchurin looked back to the time shortly after the Big Bang, which they view as a quantum process that generated lots of quantum fluctuations. Then during the period of inflation, the universe grew rapidly and these quantum fluctuations were "frozen" into classical perturbations in distinct regions. Today, each of these regions could be a different universe, having its own distinct laws of low energy physics.
By analyzing the mechanism (called "slow roll inflation") that initially generated the quantum fluctuations, the scientists could estimate the number of resulting universes at 10^10^10^7 (a number which is dependent on the model they used). However, this number is limited by other factors, specifically by the limits of the human brain. Since the total amount of information that one individual can absorb in a lifetime is about 10^16 bits, which is equivalent to 10^10^16 configurations, this means that a human brain couldn't distinguish more than 10^10^16 universes.
Requiring that the human brain must be able to count the number of parallel universes may seem inappropriate, if not arrogant, but Linde and Vanchurin explain that dealing with the quantum world is different than our everyday lives in which quantum effects can be safely ignored. A crucial part of their calculation here is an investigation of quantum effects on supergalactic scales. In this kind of scenario, the state of the multiverse and observations made by an observer are correlated (similar to the Schrodinger cat experiment, where the outcome can be determined only after it is registered by a classical observer).
"When we analyze the probability of the existence of a universe of a given type, we should be talking about a consistent pair: the universe and an observer who makes the rest of the universe 'alive' and the wave function of the rest of the universe time-dependent," the scientists write.
As the scientists explain, the calculation of the number of universes is an important step toward an even larger goal: to find the probability of living in a universe with a particular set of properties. What are the chances that we live in a world in which the laws of physics are these laws that we currently observe? Answering this question requires finding probabilities that depend on knowing about other universes, among many other challenges.
I think they mean the observable universe. I am no physicist and I only have a slight interest in quantum mechanics but I think the concept is roughly like this:
1. For every outcome in a closed system that is based on some chance quantum level event, the state of that outcome is fluid until observed.
2. It is the act of observing the outcome that places the human observer in one universe or the other.
In other words some event occurs on an infinitesimally small level that can cause two possible observable outcomes. Let's call them outcome A and B. In the writer's belief system the universe splits at this point into two identical observable universes except one contains outcome A and the other outcome B. The human observer is thrown by chance into either one universe or the other. Let's say he finds himself in the outcome A observable universe. At this point the human is completely cut off from contact with the other observable universe where presumably his identical twin lives with outcome B.
Wild stuff.
[What kind of experiments do they use to test this theory?]
Obama is funding 10^googleplex “shovel ready” science experiments to find out right now!
Great post - too funny!
All this quantum stuff is fun to ridicule, but the weird part is that to the extent we’re able to test the hypotheses they turn out to be correct. A very great deal of our present technology, notably electronics, is based on it.
Sure quantum mechanics violates common sense, but this may be more an example of the limitations of common sense than of quantum mechanics. Of course, there are multiple competing and mutually contradictory versions of QM.
The more we learn about it, the more the universe, or possibly the multiverse, appears to be a very strange place.
In physics, at least, we are more that 100 years beyond the point where we are dealing exclusively with the observable. Much of atomic theory had to be worked out without direct observation of the atom.
Observation is nice when you can get it but some things are just not observable.
What is truly mind-bending is that Obamacare will not work in any of the parallel universes.
I have been to every one of these Universes and in 99.999% of them Jimah Carter is still a loser. In the other .0001 Conservative Jimmy beat liberal Reagan for a second term- go figure!
It is my theory that there is only one universe...this one. Unfortunately Obama and his minions figure in this one and wee must vote them out.
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....In this kind of scenario, the state of the multiverse and observations made by an observer are correlated (similar to the Schrodinger cat experiment, where the outcome can be determined only after it is registered by a classical observer).
“When we analyze the probability of the existence of a universe of a given type, we should be talking about a consistent pair: the universe and an observer who makes the rest of the universe ‘alive’ and the wave function of the rest of the universe time-dependent,” the scientists write.
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This is essentially a rationale for solipsistic narcissism.
Thank God for empiricism!
I must say, I like this idea of a Clown Universe. In it, maybe nothing could travel faster than the speed of a cream pie.
When I first heard about quantum mechanics in a college physics class I couldn't believe it. I had to check it out further. I have continued to do so over the years.
The data leading to the theory of quantum mechanics is so strong and the implications are so huge you would think this would be all that today's philosophers and theologians would be talking about. The fact that they don't is very disappointing to me.
The fact that physicists are willing to consider truly bizarre theories to explain the data is very encouraging to me. I am all for the quest for truth.
Sorry if my comments sounded like I was mocking. I guess I mostly find is humorous that man is faced to ponder these bizarre conclusions.
I think you are full of crap;)
/humor mode
Sorry, didn’t mean to imply I thought YOU were ridiculing QM.
My comment was just that the theories, on their face, are indeed ridiculous.
But I guess there is no reason why the universe God created must line up with what seems logical to our feeble minds.
Pinto:
Okay.
That means that...
our whole solar system...
could be, like...
one tiny atom in the fingernail
of some other giant being.
This is too much!
-one tiny atom in my fingernail could be—
-Could be one little...
Professor Jennings:
tiny universe.
Pinto:
Could l buy some pot from you?
Theoretical? I say if a 'consensus' of scientists believe this, then we must all accept it. Why wait for a UN resolution?
All they've got is:
FAITH.
How ironic. Humans have an inbuilt need to believe in someone or something higher than themselves. Take away the proper object of that faith, and you get all kinds of craziness.
Darn. Now that you've collapsed THAT wave function, it will never happen!
I think this is a little different. I have never seen someone try to calculate the number of probable outcomes as a fixed value created at a fixed point in the past. I always read that the each observation by each observer in the set of all observers would fork a new branch. Therefore, it would have to be infinite.
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