Showing posts with label Cyclic Universe. Show all posts
Showing posts with label Cyclic Universe. Show all posts

Thursday, December 15, 2011

Multiroads to the Multiverse: Part One

If Mother Nature can create one Universe (ours), Mother Nature can create more than one universe – a Multiverse! The concept of a Multiverse, that there exists more than one universe, that is our Universe – perhaps an infinite number of them existing sequentially in time, or at one go in space, maybe both, is one of the hottest topics in current cosmology.

At the outset, there’s no law of physics (or even of God) that says that there can be (or must be) one and only one universe, our Universe.

Three questions arise – the mechanism for the origin and evolution of other universes; what types of Multiverses can be generated; and what can the concept of a Multiverse explain that the existence of our sole Universe cannot explain?

Ways, Means and Mechanisms That Generate a Multiverse:

In the infinite beginning, there existed from square one, more than one universe. No origin event(s) are required. However, those universes will evolve and ultimately morph into other universes. 

The Many Worlds Interpretation of all things quantum states that when anything within our Universe is forced to make an either/or decision, between two or more pathways or alternatives, each and every pathway or alternative is taken – because Mother Nature cannot make up Her mind between equal probabilities! Thus, to accommodate each and every possible choice, the Universe splits into as many other universes as is necessary to cater for all possible outcomes. Thus, where there existed initially one universe – our Universe – now there must exist an extra one, or two, or three, or whatever number of universes because our Universe had to make a decision between two, three, or whatever number of choices confronted it. Multiply that by how many crossroads our Universe comes to each and every microsecond, and you have the beginnings of a Multiverse in real quick-smart fashion.

Baby Universes via Black Holes: An advanced extraterrestrial technology might be able to create or manufacture baby universes by creating or manufacturing Black Holes. The recipe itself is simple – take a lump of matter and squeeze it down to such a density that its gravitational escape velocity exceeds that of the speed of light. Such is the text of ‘Universe Manufacturing 101’. Of course one doesn’t of necessity need ET. A universe with the sort of physics that permit Black Holes to form will ‘breed’ because those Black Holes will produce baby universes, presumably with the sort of suitable physics that will allow for further Black Holes, etc.

Bubble Universes via Inflation: To adequately explain various observational properties of our Universe, the concept of a rapid period of inflation around the time of the Big Bang event (I’ve seen inflation invoked both just before and just after the ‘bang’ itself) has been proposed. For the briefest of times, the Universe’s expansion accelerated at a fantastic pace before running out of puff. The fly in the ointment is that if inflation didn’t stop at the exact same nanosecond everywhere, then you’d get smaller pockets or bubbles of inflation continuing, and that each separate inflating bubble wouldn’t stop at the exact same nanosecond, creating more bubbles, etc. Each separate pocket or bubble would inflate so fast and break off from the parent inflationary event to form another universe. An analogy is to shake up a say, 1/3rd empty bottle of fizzy soft drink and open the top cap. What do you get – rapid inflation, that’s what! Bubbles form and expand and give rise to other bubbles which create new bubbles. Each bubble is its own separate universe.

Quantum Fluctuations: The vacuum energy can give rise to virtual particles, which can turn into actual particles under suitable conditions. It’s possible for the energy to come together intensely enough to perhaps create not just a pair of virtual particles, but an entire universe of particles. That could happen again and again, a multitude of times.

Video Games Analogy: There are a Multiverse of videogames within our Universe (i.e. – Planet Earth) – in two ways. One is the collective set of the thousands to maybe hundreds of thousands of individual video games within the marketplace. Each videogame equals one possible universe. The other is that each individual videogame has hundreds to hundreds of thousands of identical copies.  So the videogame Multiverse has both individuality, and sameness. Perhaps our Universe is one copy of one individual ‘video game’ or ‘computer simulation’, within a sea of thousands of identical copies of that game, within a sea of thousands of other individual games/simulations! 

Types of Multiverse:

Parallel / Shadow / Alternative / Mirror / Many Worlds / Higher Dimensional (String Theory’s Branes perhaps) universes – collectively, these universes would have the same laws and principles of physics that we know and love (unless you’re a physics student at exam time), although the ultimate nature and evolution of each and every one might differ. In other words, all these universes will be bio-friendly, though that doesn’t mean of necessity that all will contain life. Basically, these universes are all variations on a theme of our own Universe.

Simulated / Video Games Universes – Okay, within these universes, anything goes. A computer program does not have to follow or obey or simulate the existing laws and principles of physics. You want faster-than-light-travel? You got it! You want antigravity? You can have that too! Do you want your heroine to survive travel through wormholes and Black Holes? Fine! All the terrestrial superheroes and superhero powers – a Superman, a Spiderman, a Green Lantern, the list is near endless – all is possible. You can botch an operation – the patient survives. You can crash a plane – no causalities. You can make the Sun stand still; perform miracles like the resurrection; create new life forms and new civilizations, and boldly go where in our Universe, no one can every go! You can have a Heaven and/or a Hell, or live unprotected upon the surface of Venus (which is the same as Hell only worse).

Bubble / Baby / Quantum Fluctuation Universes / Cyclic or Oscillating Universes (standard Big Bang expansions followed by Big Crunch contractions followed by Big Bang expansions, etc.) – collectively, these universes could be as different as chalk and cheese in that the laws and principles of physics could vary to a greater or lesser extent – but vary, well these universes just might. Think of all the laws, relationships and principles in physics and vary them to your heart’s content. While each universe might be unique, the rules and regulations for each and everyone one is fixed.

To be continued...

Monday, December 12, 2011

Cosmology and the Multiple You: Part One

The quantum mantra revolves around the theory that in physics, anything not forbidden is compulsory - given enough time and/or space. While there is nothing forbidden about an identical twin(s) of yourself existing elsewhere in the cosmos, how compulsory that is depends on what sort of cosmological model you adopt.

You are unique, aren't you? There never has been a person exactly like you before, there isn't now, and there never will be. Maybe! Depending on what's really real in all things cosmological, the odds that there are identical copies of you out there can range from plausible if improbable, to plausible and probable, to in fact near certainty, even certainty. The key issue revolves around the concept of infinity, or near infinity. If one has an infinite number of universes to play around with, and/or infinite time, then every possible history is, sooner or later, somewhere, compulsory.

The idea of a duplicate you or two or three isn't that farfetched. Even on Planet Earth, this tiny speck within the cosmos, you have had, do have, and will have doppelgangers. But those are just look-alikes, not actual duplicates of you down to the nittiest-grittiest detail.

From the outset, 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 in a three dimensional arena and which we could potentially interact with. Think of separate houses along a street you can visit in turn as separate universes. An overall 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. Apart from those, there are parallel (mirror/shadow/alternate) universes which 'exist' - for lack of a better phrase - in other planes of existence and like houses that exist in a time instead of a special sequence, say on the same block of land, one can't easily travel from one to another. There's also the Many Worlds Interpretation variation of parallel universe, and simulated universes.

Firstly, could there be another you or multiple copies of you in the existing Universe? That's plausible, but probably unlikely.

Discussion: 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. However, even if an identical copy of you exists elsewhere out there, the probability is far greater that they already have, or someday will. The odds that two copies of you exist right now multiply the odds against by many orders of magnitude. Finally, even if another copy of you exists somewhere out there now, they are in all probability way to far away for the both of you to ever shake hands.

Secondly, could there be another you or multiple copies of you in a cyclic Universe? That's not only plausible, it borders on near certainty.

Discussion: 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 and astrophysicists are calling dark energy - which they admit they don't really understand. Anyway, despite dark energy, 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 or 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 have happened, has happened, and happened an infinite number of times. That includes in infinite number of you, and the life your leading now right 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 version of 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 again 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 or 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.

Of course in a cyclic universe, one universe dies before the next is born, so a copy of you in a previous universe is kaput before your universe comes into being, and you will be kaput before the next cycle starts, so there's no meeting of identically like minds.

To be continued...

Friday, November 18, 2011

Our Universe in a Cosmic Fish Tank: Part One

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!

THE SETTINGS

Setting Number One - Time is infinite in scope. ‘Once upon a time’; ‘in the beginning’, are two standard openings to the stage setting where ultimately, our Universe, plays its part. Alas, although there was an ‘in the beginning’ to our Universe, ultimately, IMHO there was no such thing as an ultimate ‘in the beginning’ in the broader cosmic context. In the broadest of broadest viewpoints, time stretches infinitely from cosmic horizon to cosmic horizon. Unlike all we know of regarding beginnings or creations, from our Universe, to our Solar System; to Earth; to terrestrial life, down through the ages to us, there is no ultimate beginning; there is no ultimate ending to the broader cosmic setting we find ourselves in. ‘Once upon a time’, should really read, ‘once upon an eternity’.

Setting Number Two – Space is infinite in scope. In the broadest or broadest viewpoints, there’s no such thing as an edge or a border or a boundary. Space stretches infinitely from horizon to horizon. Again, that’s not the case when just considering our Universe, our Solar System, our home planet. But, this infinite space is again part of the overall stage where our Universe acts out a role – along with probably lots of other universe actors.

Let’s call this larger context an infinite cosmic fish tank, and our Universe a fish.

Setting Number Three – There is no shape to the infinite cosmos. Why propose an infinite in space and infinite in time fish tank cosmos or cosmic setting in which to plunk our Universe - where our Universe is one of the fish? Because it does away with those awkward questions of what came before; what comes after; what lies at the farthest reaches? There is no before in the fish tank. There is no after either. There is no farthest away, only something even farther away, ad nauseam. It also does away with the need to define an overall shape to our fish tank cosmos. An infinite volume has no shape!

That said, it must be repeated and made clear that our Universe (a fish in the infinite tank) did have a beginning, and therefore one can legitimately ask what came before. Our Universe does have a finite size and therefore a shape – probably spherical. What defines the (ever expanding) size and shape of our Universe is how far out light (the speediest thing we know of) has been able to travel since our Universe’s creation, some 13.7 billion years ago. That’s the boundary to our Universe. Again, our Universe is probably a sphere, with a radius of 13.7 billion light years (a light year being the distance light travels in one year – which, at 300,000 km per second, is a long way). Or, a diameter of 27.4 billion light years.

Setting Number Four – The laws, relationships, and principles of physics (and ultimately chemistry, etc.) are universal throughout the fish tank cosmos. All the fish may not be of the same species and even those that are of the same species may have differing ages, sizes, sexes, etc. but they are ultimately all fish, subject to the universals that govern all things fish; the cosmic ‘water’ is uniform throughout.

Setting Number Five – Those fishy laws suggest that fish universes, each and every one (assuming more than just our Universe fish is in the infinite tank) are unstable – which real fish are – unstable that is. The same fish on two separate days is not the same fish, any more than you are the same you from one day to the next. You grow, you age, your cells and their components get replaced, etc. Translating to real universes, universes are unstable in that they must evolve; either expand, or contract. If there is one thing they can not be is static and unchanging. So, our infinite cosmic fish tank is a dynamic one.  Fish come and go, but the tank is forever.

BEFORE THE BIG BANG: THE BIG CRUNCH

Once upon a time there was this universe, but not our Universe. This universe existed way before our Universe existed. For some reason(s) this universe had sufficient matter/mass and thus gravity to slow down its expansion rate, halt same, and reverse the flow. Slowly, but ever so surely, this universe contracted, grew ever hotter and denser, until, like thousands of cars converging at an ever higher rate of speed, came together at an intersection. You have, in effect, the Big Crunch!

What happens when all the stuff that comprises a universe comes together? Well, what happens when you concentrate a lot of stuff into a small space? You get a Black Hole. There are probably going to be already in existence a lot of Black Holes in this collapsing universe, if our Universe is any guide. So, existing Black Holes will have a feeding frenzy as matter around them gets confined into a smaller and smaller space; Black Holes themselves can merge creating a bigger Black Hole, until finally, all mass will be inside a super Black Hole, the product of smaller Black Holes gobbling up matter and ultimately combining until a super Black Hole is all that remains of that universe. But wait, there’s more!

Think of the mass of an entire universe, all coming together at a single point in space and in time, at velocities that make Formula One racetrack driving look like a snail ploughing through molasses on a frozen winter’s night! This is going to be the Mother of the Mother of the Mother of all collisions. No Hollywood special effects team could want for more! The upshot is going to be, just prior to the finale, the existence, as noted above, of the Mother of all Black Holes. There’s going to be one hell of a massive distortion of space and time, or, space-time. The sheer momentum of such a collision, a Big Crunch, will turn space, or space-time, inside out. All that momentum can’t just come to a screeching halt in a nanosecond. What’s the result of a super collapsing Black Hole? A super massive explosion – a White Hole – a Big Bang.

BETWEEN THE BIG CRUNCH AND THE BIG BANG

Once upon a time there was this brief, but extremely intense transition between another universe’s Big Crunch and our ‘in the beginning’ Big Bang event. I’ve already suggested that pure momentum of this runaway freight train will be, as an analogy, a sock turning inside out. That ‘inside out’ event will be a pretty quick-smart happening. What happens in that brief interval of time has to do with several parameters. One is of course time - how quick – well, quick – probably several seconds to minutes. The other is space – how small – well small. But is small classically small or quantum small? Classically small refers to the minimum size of the Big Crunch vs. the original size of that universe. Classically small could still be a ‘point’ many light seconds/minutes/hours in diameter. Quantum small means a ‘point’ that is within the realm of the quantum – say atomic sized, probably way less. Logic: can you squeeze the contents of an entire universe down to the size of an atom, or elementary particle? Or, perhaps it is more logical to suggest that the ultimate squeeze is somewhat larger. Now ‘larger’ may still be tiny relative to the universe’s original size, but still one hell of a lot bigger than what’s implied by the word ‘quantum’. Yet, cosmologists would have one believe that our Universe started out as ‘quantum small’, not ‘classically small’; that quantum small somehow ruled the roost when our Universe went the way of the Big Bang event – the origin of our Universe. To me, that’s too big an ask to ask.

Any standard cosmology text will tell you about the conditions that existed within nanoseconds of the Big Bang event when the Universe was less than the size of your common cold bacterium. It was very, very super hot. It was very, very super dense. That’s what the equations say (no cosmologist was around at the time to actually observe and measure), but equations are abstractions and Mother Nature doesn’t deal with abstractions. Now both hot and dense are two logical Big Bang environmental parameters just nanoseconds past that event - but what of volume?

One can of course take any contracting object and extrapolate down to where it shrinks to a point of zero dimensions and thus have an infinite density (which therefore would be a Black Hole). But, does that reflect reality? IMHO: not on your Nellie. There must be (well, should be) some ultimate state of matter that when compressed, can’t be compressed any further. It would take an infinite amount of gravitational force to do it and the Universe, any universe, doesn’t possess infinite gravity.

What’s the minimum size our Universe (or any universe in general) could be squeezed down to? If you asked that question to any reasonably educated adult, even a kid, while you’d get a range of answers, gut feeling tells me that – unless they were well versed in cosmology – that that volume wouldn’t be within the range that couldn’t be seen with the naked eye. Now, it is dangerous to apply common sense when it comes to sussing out nature’s hidden secrets, but I’m now going to throw caution to the wind and applying this common sense dictum – The Universe, any universe, was never, repeat never ever the size that we would describe as microscopic!

Okay, so here we have this universe contracting down, getting hotter and hotter; denser and denser, and smaller and smaller as it slides into the Mother of all Black Holes, and immediately, within nanoseconds (or close to nanoseconds as the actual size allows – maybe seconds, maybe minutes) spew its guts out via a White Hole. Those guts form the contents of our Big Bang Universe. That midpoint – what was the minimum size of that transitional post Black Hole / pre White Hole event? All I’m prepared to say is that it was visible to the naked eye – assuming naked eyes were around 13.7 billion years ago! It was certainly not microscopic!

However, the really real important bit here is that our Big Bang, the product of a previous Big Crunch, happened in pre-existing time and space. The Big Bang did not, repeat, did not, create time and space. The question, ‘what happened before the Big Bang?’ has now a perfectly logical answer. The Big Crunch happened before the Big Bang.

To be continued...

Sunday, November 13, 2011

Cosmology: In the Beginning vs. Once Upon A Time: Part Two

Continued from yesterday’s blog…

HOW DO YOU CREATE A BIG BANG?

If our Universe is expanding, then it’s logical to propose that a universe can also contract. In fact, given the force of gravity, it’s very logical that a universe chock full of matter will contract under the combined force of all that gravity – which is a pull force. If a universe contracts, it must of necessity get smaller and smaller, the opposite of a Big Bang. We call that sort of contracting universe experiencing a Big Crunch event.

Now, can a Big Crunch universe give rise to our Big Bang Universe? The end product of a Big Crunch is the mother of all Black Holes. So how do you get out of a Black Hole? Well, any Black Hole, even the mother of them all, has extreme gravity, even to the extent of preventing light photons from reaching escape velocity, but that’s not the same as infinite gravity, so, given enough oomph – in this case momentum – a Black Hole can be a very quickie sometime thing. So, what’s this momentum thing? Well, it’s just the product of mass multiplied by velocity. A high mass at a low velocity can have the same momentum as a low mass travelling at a high velocity; obviously a high mass travelling at a high velocity must have a very high momentum, one that’s hard to stop. The mass of an entire universe travelling at near light speed is about as close to an infinite runaway freight train as it gets. 

I asked about the energy supply. Well, a Big Crunch universe has massive kinetic energy. As it crunches, the velocity of all its bits and pieces ever increases, until, as close to Big Crunch time as makes no odds, everything is coming together at pretty close to light speed as suggested above. It’s hard to stop massive amounts of matter, travelling at such a velocity, dead in its tracks! It is much like a swinging pendulum which has mass and velocity and so the pendulum travels from one side, through the bottom of its arc due to its momentum, and up the other side. A contracting (Big Crunch) universe will pass though its minimum (the point of least volume) and via pure momentum, start expanding (call this a Big Bang) again. That’s one source of energy oomph. The Black Hole in-between is a sometime thing.


THE CENTER OF THINGS #1

The Black Hole is at the centre of things between the Big Crunch and the Big Bang. I’ll suggest it’s a frictionless place – there are those who suggest that the interior of a Black Hole, call it a singularity, is a transformation to a new state of matter totally outside our experience. What happens at the singularity is a pretty big unknown as one can’t look inside a Black Hole, explore a Black Hole (and live to tell the tale), and even the relevant physics equations break down when trying to describe the Black Hole’s singularity environment. However, whatever a Black Hole is, and whatever a singularity is, it’s not a fantasy realm where just anything goes. Firstly, I suggest that internal conditions will be quite suggestive of extreme temperatures and pressures (the two are related). All previous structure is totally broken down and recycled back to the most elementary, fundamental bits. No structure from the previous universe survives intact into ours. Secondly, the transition into, through, and exiting a Black Hole, from Big Crunch to Big Bang, I suggest won’t alter the laws, principles, and relationships of physics. They will be the same before and after. Thirdly, the total amount of matter/energy on either side of the transition via our Black Hole centre of things will be the same. However, the ratio of mass to energy could well be different. That coupled with the random nature of quantum fluctuations means the new universe, our Universe, won’t of 100% necessity, right down to the Nth detail, be an identical clone of the previous universe. You retain your uniqueness!  

Once the former universe (now our Universe) starts expanding again, other energy sources come into play to add to the oomph. A second source of energy is that in-between a Big Crunch and a Big Bang all matter gets reduced to the basics of fundamental elementary particles due to the resulting immense temperatures and pressures present. Molecules are torn apart to atoms; atoms to electrons (and positrons) and atomic nuclei; nuclei to protons and neutrons; protons and neutrons to quarks (and anti-quarks). Now, given that this transition phase produces or reduces everything to basic fundamental matter and antimatter particles, what’s the most efficient form of energy production known? Well, it’s matter-antimatter annihilation!

Matter-antimatter annihilation plus momentum from the Big Crunch to the Big bang – well, that’s energy enough to expand our Universe to the state of play we observe today.

But wait, there’s maybe more. There’s also the contribution from the vacuum energy (perhaps the cause of an extra postulated ‘inflation’ phase just after the Big Bang event itself), and/or ‘dark energy’*** which is a push or pseudo-antigravity force apparently causing our Universe’s expansion rate to ever increase – something quite contrary to common sense given that the mass, therefore gravity, of our Universe should be slowing things down.


THE CENTER OF THINGS #2

Traditional Big Bang cosmology states that the origin or our Universe created space and time as well as matter and energy (first there was nothing; then there was something) and that space is expanding carrying matter along for the ride. Thus, there is no centre within our Universe where the Big Bang happened. There’s no set of coordinates. The event happened everywhere because in the beginning everywhere was just that one tiny Big Bang point and nothing existed outside that tiny (but now rapidly expanding) point.

Well, my untraditional Big Bang cosmology has the Big Bang event taking place in existing space and time, so there is a set of coordinates in our Universe where the event took place, and that our matter is expanding through that pre-existing space. And by the way, there’s no observational technique available that can distinguish space expanding carrying matter along like an ocean current can carry a ship, and matter moving and expanding in space, like a ship under steam moving through the water.

Well, if we’re not the centre of things, how do you explain the observation that all but the closest of the galaxies are red-shifted and moving away from us? Doesn’t that imply we have bad breath? Well, at the time of the Big Bang, not everything gets hurled outwards at the same velocity. Something hurled out faster than us will be obviously moving away from us. But, something hurled out slower than us will have us moving away from them, but from our relative perspective, it will appear as if that slower moving bit of stuff is moving away from us. So, even though there is a centre where the Big Bang happened, we still get the illusion that all things are moving away from us.

Why can’t we see the remains where the Big Bang happened? No, I won’t copout and say there’s all this interstellar/intergalactic gas and dust in the way blocking the view. Don’t forget some 13.7 billion years have gone by the boards since that explosive event. Say you are watching a candle from several miles away, both in the visible and in the infra-red (since the candle is giving off heat as well as light). Now what can you detect once the candle burns down and will obviously go out? In fairly quick-smart order you will detect bugger-all. You can’t see it any more, and in short order the now totally consumed candle will assume the temperature of the local environment. Infra-red wouldn’t distinguish it (or the burning event) from all that’s nearby. Our Big Bang event happened so long ago that the residue has become part of the background common to everywhere else. So, we can’t pick up the specific location anymore. Too much time has elapsed. 


HOW DO YOU CREATE A BIG CRUNCH?

Well, the obvious way is that an expanding universe has enough stuff, enough gravity, so slow the expansion down until it ceases, then reverses direction and starts to contract under that gravity, very slowly at first, but over time as stuff gets closer together, faster and faster until like cars meeting at an intersection, everything comes together at one point in space and time. That’s your basic Big Crunch.

But, our Universe isn’t apparently going to do the Big Crunch boogie. However, there is an alternative way. If our Universe is ever expanding, and meets another universe that’s ever expanding, then the partial intersection of the two might increase the overall mass density sufficiently to cause that local intersected area to start contracting. And when that contraction reaches its logical conclusion, you have a – wait for it – a Big Crunch. 

The inhabitants of a doomed Big Crunching universe could in theory escape their fate because there is an outside (the wider infinite cosmos) to escape into.


ALTERNATIVES

Other island universes may have had other origins and/or fates compared to ours. Our Universe had a Big Bang origin and apparently will have a Heat Death final. Another universe may have a quantum fluctuation beginning and a Big Crunch ending. Maybe all universes, including ours, are cyclic as the result of (via string theory) two branes colliding (the Ekpyrotic universe theory).

As long as the origin of our Universe happened in pre-existing space and time, I’m a happy camper.

Not up for grabs in this essay, or in the context of the infinite cosmos including our Universe and all other universes within, is the Many Worlds theory of all things quantum, nor ideas central to the concept of a parallel/alternative/mirror/shadow, etc. universe(s) as they fall, assuming they exist at all, outside our space-time continuum.


***I’ve often wondered whether ‘dark energy’, a push or repulsive force, could be the result of our Universe having a slight excess of positive charge over negative charge (or vice versa) – although our Universe is supposed to be overall charge neutral. If it is not, and since like charges repel or push, a surplus of either positive or negative charge would give our Universe an overall repulsive force edge to it. 

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...