Monday, October 31, 2011

Cosmic Fun: Random Ramblings in Modern Cosmology: The Infinite You: Part One

The following ideas are primarily mine alone, the good, the bad and the ugly, albeit based on and influenced by reading multi volumes of tomes in modern cosmology. However, I’m also quite sure that numerous others have quite independently thought somewhat similar, if not exact, thoughts as well. Therefore, I’ll take no credit for being right, if I don’t get blamed for being wrong!

THE INFINITE YOU

Firstly, some definitions are in order. We have the ‘observable universe’ which is that part of the entire Universe we can actually see in the here and now. Parts of the Universe that exist, but which light hasn’t yet reached us, aren’t part of our ‘observable universe’ – yet. The ‘Universe’ is all that we can ever know about, regions seen, and regions as yet unseen. Then there is the ‘Multiverse’ which, if it exists, are a conglomerate of separate Universes, each of which exists as a discrete entity. An analogy could be the nucleus part of a liver cell (our ‘observable universe’), the entire cell (the Universe), and the grand collection of liver cells – the liver Multiverse as it were.

1) The Infinite You In The Existing Universe: The existing Universe could be as near to infinite as makes no odds. It obviously can’t be infinite, because it would take an infinite amount of time to expand the Universe to an infinite volume, and we know the Big Bang took place less than 14 billion years ago. And, the Universe can’t contain an infinite amount of ‘stuff’, otherwise it would have to have an infinite volume to house it all. The fact that our night sky is dark, suggests that there can’t be an infinite number of stars and galaxies in our observable universe, otherwise, no matter in which direction you looked, you’d see a star or galaxy and the night sky would be as light as the daytime. However, from our point of view, while not infinite, the Universe is still BIG! And it does contain a lot of stuff. It is within the bounds of possibility that within such a vast space, by chance, there could be a duplicate(s) of you, even more identical to you than any identical terrestrial twin you might happen to have. The odds aren’t very high to be honest, but they aren’t zero.

2) The Infinite You In A Cyclic Universe: Current cosmological observations suggest that our Universe began some 13.7 billion years ago in a Big Bang. Alas, the expansion of our Universe appears not only not slowing down, but ever accelerating due to something cosmologists/physicists are calling dark energy – which they admit they don’t really understand. Anyway, many cosmologists cling to the concept that eventually the expansion will slow down, halt, and reverse, resulting in ultimately a Big Crunch billions of years in the future. That Big Crunch leads directly to another Big Bang – expansion – contraction – Big Crunch – Big Bang, etc., etc. Thus one has an ever oscillating/cyclic Universe with no beginning and no end. Ah, the concept of infinity (this case in time) rears its head. Since the Universe has already gone through an infinite number of these cycles, as surely as night follows day follows night, anything that could of happened, has happened, and happened an infinite number of time. That includes in infinite number of you, and you’ve led the life your leading now exactly down to the last detail an infinite number of times, as well as leading differing lives in every possible variation from the major (marriage, career, children, lifespan, etc.) through to the relatively minor, right down to the highly trivial (like an infinite number of lifetimes absolutely identical to the current one except for one morning when you had an ever so slightly different breakfast cereal). Just think, somewhere in the infinite past, there was a you who lived an entire lifetime driving a car and never hit a red light! Again, anything that is within the realm of possibility, even if improbable in the extreme, has happened, and has happened an infinite number of times. Such is the nature of infinity.  The other nice thing about an infinite Universe (whether in time or space) is that all those unsuccessful eggs and sperm, all those failed/un-germinated seeds, all those spores and pollen that never bore fruit, all those lives that never were, all now get their moment in the sun!

There’s an interesting variation on the above theme. Most of us are probably familiar with the sci-fi idea of being caught in a time-loop. You repeat an interval of time over again and again, probably until some weird sense of deja vu alerts you that something’s not quite right. Expand the idea to the grandest scale possible. Big Bang – expansion – contraction – Big Crunch – Big Bang – expansion, etc. but each cycle isn’t a new cycle with a new history and new possibilities rather each cycle is absolutely identical to the one that came before, and the one before that, etc. So, there will be an endless number of you, but there will be no wild new things in your lives, just the same old life, again and again. Maybe that’s where we get our now and again sense of deja vu from. 

3) The Infinite You In A Multiverse: We live in a Universe that is very friendly to life-as-we-know-it (life-not-as-we-know-it is another can of worms that need not concern us here). That is, it seems that the various physical laws and physical constants are fine tuned to allow our kind of life. If any of those values were slightly greater or slightly lesser, the biophysics and biochemistry that allow organic life forms to exist wouldn’t be possible. For example, if gravity were ever so slightly weaker, atoms/molecules wouldn’t coalesce into macro-bodies like galaxies and stars and planets. If gravity were ever so slightly stronger, stars would be far more massive on average, and the more massive a star, the shorter it’s lifespan, to the point where there wouldn’t be enough time for life in a young solar system to develop before the parent star went poof! So, that fine tuning leads to a trio of possibilities.

The first is that we (meaning the Universe’s life forms) are just incredibly lucky that our one and only Universe just happened to meet all the Goldilocks criteria that allow us to exist. The second is that there is indeed, an intelligent designer responsible for those conditions. For want of a better word, let’s call this intelligent designer “God”. (There’s an interesting variation on this theme and that is this Universe was created by an extraterrestrial intelligence in another Universe, a feat which might be relativity simple to a highly advanced technology able to manipulate the basic forces of physics.)

The third possibility is that there is a Multiverse. We can all agree that our Universe is a Goldilocks universe. We can also all agree that we can imagine other universes, while superficially akin to ours (it would at least have space and time), have differing values for some of all of the physical properties we associate with ours – differing values for the physical constants, the types and numbers of physical forces and particles, the physical laws that are part and parcel of physics, etc.  It’s akin to humans – we’re all superficially similar, yet each one of us (past, present and future) is unique (even identical twins differ and the same applies to clones as well as nurture affects us as well as nature). So, like we have a multiverse of humans, we could have a multiverse of universes (the Multiverse), some of which, like ours, will be Goldilocks universes, although most won’t be because some critical constant(s) or force(s) or particle(s) or law(s) will be too different enough to allow the complexity we associate with life.

In other words, there exist dozens, hundreds, thousands, hundreds of thousands, maybe multi-millions or billions (or more) of Universes where the physical laws and constants may well be different. That being the case, most Universes will be barren of life because their physics, hence chemistry, aren’t compatible with life-as-we-know-it.  But a few, by chance, will be Goldilocks Universes. It wouldn’t surprise anyone that because we exist, our Universe must be a Goldilocks Universe.

How exactly a Multiverse would come about is neither here or there. But there is at least one theory. To help explain various observational cosmological anomalies that would follow a traditional Big Bang, several decades ago the idea was floated that immediately following the Big Bang came a period of ultra-rapid inflation, before the expansion settled down to a far slower rate. Today, inflation is widely accepted as part and parcel of the Big Bang model. However, inflation need not have ceased at the exact same nanosecond everywhere. That is, if inflation continued on at one point, another Universe would quickly form, and if inflation didn’t shut down exactly at the same moment, another bubble or pocket or baby Universe would bud off, and so on and so on, resulting in a sort of bubble/foam collective of Universes – the Multiverse.

The upshot is that lots of Universes (a Multiverse), could mean a lot of you!

4) The Infinite You In Parallel Universes: There is a theory (known I believe as the ‘Many Worlds’ theory) that each time anything, from fundamental particle to human being, comes to a fork in the road as it were, has to make a choice(s), both/all forks are taken (something can be, and not be at the same time). To accommodate both/all alternatives, this quantum (in the case of the micro), or decision making (in the case of the macro), the entire Universe splits, and where we had one Universe, we now have two (or more), one for each fork. Of course when you consider the number of forks that the Universe encounters, well it’s been calculated that every second, some 10 to the 100th power of Universes need to be created. (Just think how many hundreds, perhaps thousands of decisions (usually quite trivial, often subconsciously) you make every day. There has to be a new Universe to accommodate every alternative. Of course that means that when you add up all these collected Universes, there must be a lot of you, and a lot of everything else, each one ever so subtly different. In the case of Schrodinger’s Cat, there are now two Universes – one with a dead cat; one with the cat alive and well and doing its cat thing.

To be continued...

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