Monday, June 10, 2013

A Cosmos Unto Infinity: Part Two

The nature of, the size, the shape and the duration of our Universe has been speculated and debated upon ever since humans gazed in wonder at the night sky. Though ideas have waxed and waned, and though modern cosmology is more focused than ever on actual observations, speculations, well that’s still the case today. My take, albeit slightly more philosophically inclined, is that our Universe is just part of an overall infinite in space and infinite in duration cosmos. 

Continued from Part One

As we noted in the example of the fridge and your body, it takes energy to reverse entropy or at least hold it at bay. A reversal of entropy is sort of like that closed box with Maxwell’s Demon (representing energy) that controls a slot that the Demon can either open or close that’s in the middle of that closed box that’s of a uniform temperature.  The Demon opens the slot whenever a rapidly moving (hot) molecule heads toward the left side or when a slower moving (cold) molecule heads toward the right side. After a while, the left side of the box will be containing just hot stuff (rapidly moving molecules) and the right side cold stuff (slowly moving molecules). Maxwell’s Demon is like a kid expending energy sorting a bag of 1000 various coloured marbles (maximum disorder) into piles of reds and greens and blues and yellows (maximum order).  Of course our infinite cosmos contains no demons, and marble-sorting kids need not apply if there’s ever a job ad for restoring order to an infinite cosmos.

Okay, without demons (or entropy reversing kids), our infinite cosmos heads towards a state of maximum entropy or maximum disorder or maximum uniformity. The cosmic temperature will be the same everywhere; matter will be evenly distributed. But, can an infinite cosmos ever reach such a state? It could or should take an infinite amount of time, but that’s also assumed. 

Yet alas, what even an infinite cosmos needs is a Maxwell’s Demon. The cosmos, if it is to retain a state of vitality for an infinite duration, needs something that recycles stuff that’s at maximum entropy (maximum disorder) back to the basics of minimum entropy (or minimum disorder) where useful things can continue to happen.

* The Role of Gravity

Gravity seems to be a Maxwell Demon’s kind of force that keeps on keeping on. As long as you have two bits of matter, even just two electrons, you have gravity. Radiation (electromagnetism) could be dispersed evenly in infinite space over infinite time, but it is hard to imagine that situation with gravity. The only real way gravity could be rendered inert and useless as an energy source would be if it was 100% concentrated in just one place – like a super ultra mother of all cosmic Black Holes. The only other way gravity could be nullified would be in matter were distributed so absolutely evenly such that every bit of matter were being gravitationally pulled on absolutely evenly in each and every direction. But the slightest nudge or deviation from this ideal theoretical state (inevitable given quantum fluctuations) would throw everything out of equilibrium. But because matter is energy and energy is matter, if gravity can disrupt the distribution of matter from a state of near perfect uniformity, then energy will follow the short and curly material bits. Light (photons) reacts to gravity as much as electrons do. Further, the one extra nice property that gravity has is that it can’t be blocked. You can block out light or shield yourself from electromagnetic effects, but nothing will shield you from gravity.

* The Recycling Role of Radioactivity

Fortunately, there are several basic ways of recycling complex cosmic stuff back into the cosmos in the form of simple stuff. The first of these however has issues. Gravity can contract and pull together interstellar gas and dust into a proto-star which will ignite under pressure via thermonuclear fusion to form a radiant star. Stars however fuse lighter elements into heavier elements, and when a star goes nova, or becomes a supernovae, those heavier elements increasingly form the next generation of interstellar gas and dust. Eventually, after many generations of enrichment, interstellar gas and dust is lacking in those lighter elements (mainly hydrogen and helium) which easily undergoes fusion. Heavy elements, like iron, just won’t fuse any more and so the continued formation of radiant stellar stuff grinds to a halt. But, there is an escape clause.

Among the heavy elements; elements that stars manufacture, are radioactive elements with unstable atomic nuclei. Radioactive decay re-releases back into the cosmos those fundamental bits and pieces that can reform into those lighter elements that are the basic building blocks for forming radiant stellar objects. There is cosmic recycling from the simple to the complex and back to the simple again.

* The Recycling Role of Cosmic Black Holes

The second way of cosmic recycling is, believe it or not, via cosmic Black Holes. Astronomical Black Holes, via the vacuum energy (quantum foam or fluctuations) and quantum tunnelling, can release elementary particles back into the cosmos. As mentioned earlier, this is known as Hawking Radiation, after theoretical cosmologist/astrophysicist Stephen Hawking. Complex stuff can go into a Black Hole, but just very simple stuff ultimately comes back out again.

* The Recycling Role of Life

Life can be an entropy buster as in the case of Maxwell’s Demon, the kid who sorts the marbles, the mum who does the housework, the bird or beaver who gathers up forest debris to make a nest. But, it takes outside energy to accomplish these things and at the end you haven’t decreased complexity – the marbles are still marbles; twigs are still twigs. But microbes like bacteria, etc. can break down complex stuff (like twigs) and turn it into less complex stuff which can be recycled into hundreds of new and different complex things. So, when our home planet eventually meets its Waterloo, and gets scattered back into the cosmic winds, thanks to bacteria, there will be more simple stuff floating around than would otherwise be the case

So complex stuff gets recycled back into simple stuff, all brought together again by gravity to ultimately form complex stuff again. The cosmos receives recycled stuff back, from which it can keep on keeping on!    

* A Fly in the Ointment

In a cosmos that’s both infinite in space and infinite in duration, here’s an interesting ‘angels on the head of a pin’ question. There are two forces which in theory can extend their influence indefinitely, that is, unto infinity. They are electromagnetism (of which light is a prime example) and gravity. So, can the influence of a force cross an infinite space if it has an infinite amount of time to do it in?

Perhaps Maxwell Demon’s ‘closed box’ isn’t really an appropriate ‘container’ for an infinite cosmos. If the cosmos is infinite, can it be described as a closed system? 

The Multiple You

And so finally, consider and reconsider the quantum mantra: “Anything that isn’t forbidden is compulsory; anything that can happen will happen”. That’s even more the case when you have infinite time and space to play around with! So, I add to that mantra “and will happen again and again and again, an infinite number of times”. That actually means, or at least very strongly suggests that every possible scenario, every possible history, and every possible variation on each and every scenario or on any theme that you care to think of or think up will happen again and again and again. That, by the way, includes you. You are a scenario, and you, and every possible variation of you and your history will transpire numerous times; actually an infinite number of times. If that isn’t spooky, I don’t know what is, but it’s a logical consequence of having an infinite cosmos. 

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