INTRODUCTION
The Big Bang origin-of-our-Universe event was not the be-all-and-end-all of things. The Big Bang event was but a minor event in the larger cosmic scheme of things. If the elementary particles that comprise your mind and body could talk, what a tale of eternity they would tell!
Continued from yesterday’s blog…
OUR BIG BANG ALPHA
Once upon a time there was this Big Bang origin of our Universe. Any Big Bang worthy of its salt results in an expanding Universe. What’s the evidence for the Big Bang, that our Universe is expanding (exploding?) from a point back in time (and therefore by running the film backwards contracting back to that point in time). Well, there are four lines. The first is theoretical. All universes are unstable (as noted above) and must either expand or contract. The second is observational – the cosmic microwave background radiation (CMBR). An explosion – something hot – expands and cools off. The CMBR is the Big Bang’s heat that has now cooled after 13.7 billion years of expansion. The third is also observational – distant objects in space exhibit a red-shift – they look slightly redder than they actually are because they are moving away from us. The farther away, the faster they are moving, the redder they are. If they were moving towards us, they’d appear slightly bluer. The relationship between distance from us and velocity is what you’d expect from something that went ‘bang’. Lastly, also observational, is the distribution of objects out there. If there were no ‘bang’, then the distribution of objects (galaxies and clusters of galaxies) in space would be more evenly distributed than what’s observed.
Ah, but where are the coordinates – that place in space – we can point our telescopes towards and literally see the remains of that Big Bang explosion? I mean we see the after affects of stellar (supernovae) explosions like the Crab Nebula which occurred in 1054 AD. Well, there’s a vast time difference between 1054 AD and 13.7 billion years ago! By analogy, say you have a fireplace, and on a cold winters night you fire up same, and thus warm up you home to a comfortable level. But after a while, the fire burns out. If you leave the house, but return after a few hours, you will note that your fireplace is still a tad warmer than the rest of the house. That’s like the 1054 AD event. But, now say you go on vacation and don’t return for say a month after-the-fact. When you do, will your fireplace be any warmer than the rest of your home? No! Well, that’s equivalent to the 13.7 billion years. We can’t place those Big Bang coordinates because they have cooled to such an extent as to be the same temperature as the rest of the house, or Universe in this case. The place, those coordinates, of the Big Bang event no longer has any distinguishing features our telescopes can pick up on.
NOW
Once upon a time, a time we collectively call ‘today’ or ‘now’ or ‘the present’ is all we have to measure what came before and what will come after. What we currently believe is not what was believed a century ago; a thousand years ago; ten thousand years ago. Probably, a century from now; a thousand years from now; ten thousand years from now, what we believe about the Alpha and the Omega of our Universe, and its place, if there is a place, in an even larger context, will probably be as different. Knowledge evolves. The cosmology I learned as a teenager is already vastly different than the cosmology I read about today as a retiree. However, today is all we have to work with, but keep in mind it’s a work in progress. So what do we believe now? One – our Universe had a beginning. Two – our Universe won’t go out with a bang (or a crunch), but with a whimper, just slowly fading away getting thinner and thinner as if our Universe is on some sort of eternal diet. Three – our Universe is the be all and end all of all there is. What can we however speculate on now? One – There was a ‘before’ before our Universe began. Two – our Universe may have a different fate in store, and it could end in a bang (or crunch), not a whimper. Three – there may be far more to the cosmos than has yet been dreamt of in anyone philosophy. In fact, if one looks at the history of the size of our cosmic neck of the woods, the trend has always been towards a vaster and vaster cosmos. If our ancestors could only know then, what we know now, their minds would have been so boggled as to probably defy description. So, if we could know now, what our future generations will know, no doubt our heads would hurt too!
Part of our ‘now’ is the presence of something called ‘dark matter’, of immense importance to things cosmological, that cosmologists can’t yet explain or identify. Okay, I’ll make an heroic speculative effort to explain it in the light of what I’ve postulated above.
Now, it has been speculated that matter that gets sucked into a Black Hole undergoes a phase change into a new form of matter, sort of like ice to water to steam, or steam to water to ice. What exactly the nature of that inside-the-Black-Hole phase change is – well, your guess is as good as mine. However, I have come up with an idea. The matter sucked inside a Black Hole has been transformed into ‘dark matter’! Now ‘dark matter’ has mass and gravity, but doesn’t interact with any electromagnetic forces. We know that because ‘dark matter’ exists within our Universe; not of necessity hidden exclusively within Black Holes. So, how does ‘dark matter’ get out of a Black Hole and into our Universe at large? It doesn’t, at least not as ‘dark matter’ but maybe a Hawking radiation. Well, that doesn’t explain the ‘dark matter’ all around us. So there has to be an exception, and I suggest that exception was the transformation of a previous universe’s Big Crunch – forming the Mother of all Black Holes – so warping space-time that it turned itself inside out and emerged as a While Hole, spilling out its contents and forming our Universe in the process. The Mother of all Black Holes transformed much of that universe’s ordinary matter into ‘dark matter’, but the process of Black to While Hole transformation happened so rapidly that not all matter got so converted before the spewing. So, what was vomited as our Universe was a lot of ‘dark energy’, but not quite 100%, keeping in line with what we observe, or rather detect but don’t directly observe, today.
THE FATE OF OUR UNIVERSE OMEGA: HEAT DEATH & THE BIG RIP
Once upon a way, way, way future time, our Universe will be drastically different than the one we know today. There are three possibilities. Firstly, the total amount of gravity (a pull force) will be enough to cause our Universe to slow down, stop, and reverse direction, to ultimately result in a Big Crunch. That’s unlikely based on current observational evidence. Secondly, the Universe’s gravity could be just enough to slow the expansion rate of the Universe down, such that it reaches zero velocity after an infinite amount of time. That sort of knife-edge balance is unlikely. Way too many factors have to balance each other out. It’s like tossing a ball at a ceiling hundreds of metres high, and having the ball just stop its upward trajectory just as it ever so barely caresses the ceiling. That’s way too unlikely a scenario. Thirdly, the Universe’s gravity won’t be enough to stop, far less reverse the expansion, and thus our Universe will forever, and forever, and forever (amen) grow ever bigger, ever decrease in mass/energy density, until overall, there’s so little energy available per volume of space that even one minute of warmth will be worth thousands of times what the price of gold is today. In fact, it will be priceless. That’s what is known as the Heat Death fate of our Universe.
Current observational evidence suggests the third option as the likely option. Contrary to expectations, our Universe’s expansion rate is not slowing down (under gravity’s pull force), but is instead accelerating under a currently postulated but mysterious ‘Dark Energy’ (push) force. Now this ‘Dark Energy’ push force is a function of space itself. The more space, the more ‘Dark Energy’ there is. Space is of course expanding, so ‘Dark Energy’ is becoming ever more dominant. Eventually, ‘Dark Energy’ could be powerful enough to push clusters of galaxies apart; push the components of individual galaxies apart; then the stars that comprise those galaxies and the solar systems that surround those stellar systems. ‘Dark Energy’, as it grows more powerful, could then push apart stars and planets; hence the molecules than make up those bodies into atoms. In turn, those atoms could be pushed apart into their fundamental particles – quarks and electrons and photons, etc. Whether or not quarks and electrons and photons can be further torn apart – well, that’s pushing the boundaries of current particle physics. Anyway, all this pushing apart is collectively termed ‘The Big Rip’.
The interesting bit is that if there is an outside of our Universe, then in theory, humans – assuming there are humans around trillions of years hence – or other intelligent life forms will be able to escape the Heat Death and/or Big Rip.
One obvious question rears its ugly head. If our Universe originated from another Big Crunch universe, and if our Universe is not fated to end in a Big Crunch, that breaks any sort of expected oscillation or cycle. Our Universe in turn can’t generate another universe further on down the track. Yet it should since we presumably inherited that previous universe’s full compliment of matter and energy and thus should be fated to ultimately Big Crunch as well. Presumably, something happened during the Big Crunch – Big Bang transition to perhaps siphon off some of the matter/energy and send it to an else-where or else-when. The extreme physics that would operate during such a transition aren’t well understood and I have to leave open the possible that something more relevant to “The Twilight Zone” can happen. Of course perhaps something further on down the track might revise the current expectations for the fate of our Universe – the pendulum could swing back towards a Big Crunch scenario.
So, how do we get Big Crunches?
There are two possible ways. One is a universe that’s massive enough to collapse, generate a new universe, which then collapses and the cycle repeats. No “Twilight Zone” weird physics happens within the transition, or at least not enough to alter the outcome. The other is to have one ever expanding universe intersect another ever expanding universe. The area of intersection would increase (double) the mass/energy content within that area. That then might be enough to cause that area to start contracting and ultimately Big Crunch. This is similar to, say one supernova spewing out dust and gas; another supernova – ditto. The intersection of part of the two expanding regions of gas/dust is then enough to cause a local contraction of the combined gas/dust, ultimately forming a new, next generation, star, probably an entire stellar system (star + planets).
DOES THE COSMOS CARE?
In our Universe, stars are born; stars die. Their matter and energy get recycled into new stars. In our cosmic fish tank, universes are born; universes die and their matter and energy get recycled into new universes. It doesn’t really matter whether a universe dies in a Big Crunch or in a Big Rip/Heat Death. The elementary bits and pieces, electrons and quarks and photons are eternal or immortal. They, unlike us, don’t age. And so, in the broadest of broadest of points of view, our Universe comes to some sort of end, but ‘life’ goes on. The fish tank cosmos doesn’t concern itself with the end of our Universe, any more than our galaxy gives a stuff about the end of our solar system, no does our Sun concern itself with the petty affairs on one of its planets – Earth. Humans may care – all else is indifferent.
AN ULTIMATE TRUTH
Whether or not there was some sort of ultimate beginning; whether or not there will be some sort of ultimate ending, the bits and pieces that currently make up you, were there and will be there. That, in one sense, makes you as immortal as the cosmos itself.
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