Afterlife Theories - What Happens When You Die?

Whether you believe a fabulous eternity in Heaven awaits you, or our death simply results in us becoming worm food, the idea of an afterlife is a fascinating topic to discuss and ponder. We look at some of the more interesting theories that have been proposed about the eternal question - what happens to us after we die?

The Infinite Universe Theory

This is one of the more mind-blowing ideas of the afterlife, and is based upon the notion that the universe in infinite in nature - it simply continues on forever, unmoved by the passage of time or any kind of finite label we'd like to apply to it with our simplistic primate minds.

The basic idea is that you never really 'die' as such. The universe goes through an infinite amount of change and rearrangement, but the information that makes you aware is still there, just in different forms.

Given an infinite amount of time, anything that's conceivable and possible will happen. Anything you could possibly think of will happen in an infinite universe – whether it's Brad Pitt becoming ruler of the known universe, or your boss being eaten by a dinosaur, it will happen at some point in a truly infinite universe. So, given an infinite universe, the information that makes you aware will get recycled and turn into something else that's aware.

Even if this process takes billions of years, you wouldn't be aware of it, because you don't have consciousness while your atoms are scattered across the universe, in the forms of inanimate objects, animal faeces, stardust and the like.

Over an incomprehensible amount of time, due to chance, this genetic make-up will be replicated and thus a being with the same consciousness as you will be reborn. Since when you die, you are not conscious, time is irrelevant. Thus, from your point of view, from the moment you die your consciousness will be instantaneously recreated in another form.
This theory makes some assumptions – first, that consciousness is an emergent property of a purely physical source, created only by the particular arrangement of physical cells, neurons and chemical reactions that comprise our brains. If consciousness is created from something else, or a combination of physical factors and some quantum or otherworldly element we can't yet identify, this theory loses a lot of traction.

The other huge assumption that this theory makes is that the universe is actually infinite.

The idea of an infinite universe might seem preposterous, in a world in which we seem to have finite resources and finite time, but mathematically, infinite cannot be disproven; in fact, all the proof you need is in the very symbol itself, infinite ∞, which represents the ability to just keep on counting…. forever.

The fact is, there simply is no 'highest number' you can reach before you come right back around and head towards 0 again. You can always add another number on to the highest number you think you've reached. And you can always add a number onto that, and so the cycle continues endlessly. This is the very nature of infinite – a universe that simply does not end, in which all possible scenarios are played out, and virtually anything you can think will happen in the universe at some point.

Even the most unlikely of events, with probabilities that are extraordinarily low, can and will happen in an infinite universe. Hey, we're here, aren't we? The probability that humankind was spawned from the bowels of evolution and survived long enough to build our great civilizations and cities, leading the way for your parents to meet and for you to be born is infinitesimally small; just look at this infographic to shed some light on just how improbable you are:

So, now you're beginning to see the picture. An infinite universe means everything must happen, no matter how ludicrously low the probability. In some ways, the very existence of humankind and of you, sitting in front of your computer, is almost proof enough of an infinite universe.

The alternative, that you were created by chance in a finite universe, seems far more implausible and is almost mathematically impossible. The other alternative is that we are designed, which is a whole other can of worms altogether, and a scenario which there's no real evidence for.

Therefore our existence most likely arose in an infinite amount of time by chance, and consequently, as soon as you die, you'll instantly reawaken again as your recreated consciousness.

It's also possible that the infinite form of the universe manifests itself through repetition – so rather than this universe going on forever, the universe does die, but it is simply reborn again and again via a series of Big Bangs and Big Crunches, and we go through the whole process again. So you could even be reborn as yourself in a universe 40,000 universes down the line.

Either way, it's a fascinating theory indeed. It would be truly epic to die only to have the winds of life blown into a strange, alternate version of yourself, in an incomprehensible amount of time in a strange and alien future.

The Many Worlds Theory

This idea of the afterlife stems from the theory that there are an infinite number of parallel universes, and every single time an action occurs that has more than one possible outcome, the universe splits into distinct universes to accommodate each of the possible outcomes.

So when you die, you only die in this universe. There's an infinite number of universes out there where you're still alive and kicking. You'll also be born again in any number of parallel universes, living out your life again and again, with some lives wildly different from each other (perhaps you go from being a dentist to a rock star), and some lives only having the most miniscule of differences (you decided to have raisin toast for breakfast instead of cereal).

The horrifying reality of such a scenario means you will die in every imaginable way too. There's probably a universe in which you didn't look left and got hit by a train, or a universe where your home was invaded and you were brutally stabbed to death. But on the flip side, you will also get to experience all the beauty that life has to offer; there might be a universe in which you strike it rich from an early age and live a life of unimaginable luxury and decadence.

A thought-provoking take on this idea is that the phenomenon of déjà vu is actually two universes colliding, so you feel like you've experienced that moment before because you have, albeit in another universe.

What's interesting about the Many Worlds theory is that it actually has a non-trivial amount of scientific conjecture and arguments to support it. It's far from being a 'proven' theory, but even prominent physicists such as Michio Kaku and Hugh Everett have argued in favour of parallel universes and the 'Many Worlds' theory.

The parallel universes theory first arose after the initial discovery and subsequent analysis of quantum mechanics, the spectrum of physics that deals with the behaviour of matter at very small scales.

The study of the behaviour of matter at the subatomic level led to some bewildering discoveries, and the realization that matter at that scale does not operate according to the traditional classical laws of physics.

I won't go into the depths of quantum physics here, because as they say, 'If you think you understand quantum physics, you don't understand quantum physics', but the general idea is that while we think of everything we come into contact with – trees, chairs, other people, the entire world around us, as having a definite state and measurable quality to it, particles at the subatomic level don't have definite values. Rather, they are uncertain (defined in terms of probability) and only take on a definite value once they are observed.

Consequently, some interpretations of quantum mechanics suggest that observing and measuring a quantum causes an actual split in the universe. The universe is literally duplicated, splitting into one universe for each possible outcome from the measurement.

So for example if you rolled a 6 sided dice, it might land on a 3 in our universe, but actually the die actually landed on all 6 sides simultaneously – and for each possible outcome of that die roll, the universe was split 6 different ways.

The parallel universe theory also aligns well with a relatively recent branch of physics known as String Theory, which proposes that the fundamental building blocks of matter and the physical forces of the universe exist on a subquantum level. These building blocks resemble tiny rubber bands (or 'strings'), and these strings comprise another level of matter known as 'upquarks' (quantum particles), which in turn produce electrons, atoms, then all the way to cells and the physical matter we see and feel around us.

The central tenet of String Theory is that the vibration of these rubber bands, these strings, causes and influences the behaviour of all matter in the universe, and that this vibration happens across 11 separate dimensions.

String Theory suggests that our universe is analogous to a bubble, existing alongside similar parallel universes, and that gravity can flow between the universes. When the universes interact with each other to a sufficient degree, a Big Bang occurs and another universe is born.

To someone unschooled in advanced physics, String Theory might sound utterly ridiculous, but when one of the world's most respected and prominent physicists, Michio Kaku, preaches the possibility of this theory being real, and of parallel universes existing, then you have to sit up and take notice.

So, whichever exact interpretation of the parallel universes theory you subscribe to, the consequences are mind-boggling to the extreme.

The Simulation Theory

These theories of how the afterlife might exist are getting even stranger. If you've seen The Matrix or The Thirteenth Floor, you'll already be very familiar with this theory. The idea is something like this:

If it's possible for humans one day to simulate our universe (even if it's a much smaller one), then by logical conclusion it's also possible for a being in that universe to also simulate a universe. The simulated universe in that universe can also simulate a universe, and so on. Not only that, but each of them can simulate more than one universe as well.
So what you end up with is a virtually infinite amount of simulated universes, and one real universe.

How do we know we're in the real universe or a simulated universe?

Answer: we don't.

And if we are in a simulated universe, the potential is there for some form of afterlife, as strange as might be – perhaps our universe simply gets rebooted after a certain point, and we relive our lives over again? Or perhaps we're actually the 'avatars' of a higher level being in a universe above us, and when we die, we'll wake up in some incomprehensibly strange alien being, having just experienced that being's equivalent of an afternoon Call of Duty session.

The simulation theory has some scientific credibility, although it's not yet been comprehensively investigated as a possibility (probably because it's impossible to do so), and was first brought to the scientific community's attention by Nick Bostrom with a paper in 2003 titled 'Are You Living in a Computer Simulation?', proposing an argument for a simulated universe. An excerpt from the paper outlining Nick's central argument is below:

"A technologically mature "posthuman" civilization would have enormous computing power. Based on this empirical fact, the simulation argument shows that at least one of the following propositions is true:

1. The fraction of human-level civilizations that reach a posthuman stage is very close to zero;

2. The fraction of posthuman civilizations that are interested in running ancestor-simulations is very close to zero;

3. The fraction of all people with our kind of experiences that are living in a simulation is very close to one.

If (1) is true, then we will almost certainly go extinct before reaching posthumanity.

If (2) is true, then there must be a strong convergence among the courses of advanced civilizations so that virtually none contains any relatively wealthy individuals who desire to run ancestor-simulations and are free to do so.

If (3) is true, then we almost certainly live in a simulation. In the dark forest of our current ignorance, it seems sensible to apportion one’s credence roughly evenly between (1), (2), and (3).

Unless we are now living in a simulation, our descendants will almost certainly never run an ancestor-simulation."

Whether the simulation theory is a load of bunk or we are indeed something akin to a casual experiment run by a wealthy and bored scientist or engineer of the distant future, it's extremely interesting (and a little frightening) to think about.

The Heaven and Hell Theory

Ahhh, good old Heaven and Hell, the bastion of classical Middle Eastern religions. What other belief has shaped and guided the path of humanity more than the oft-told doctrine of Heaven and Hell? Not many, I venture to say. This belief, propagated throughout the ages, is expressed in slightly different forms depending on the religion, but is essentially based on the idea that we all have eternal souls, and depending upon our actions in this life, we will find ourselves either standing at the gates of Heaven or burning in the fires of Hell.

Obviously there's not much scientific evidence to suggest this is even a remote possibility; you can hardly refer to an ancient book written by people who knew comparatively little about the universe as reliable proof, but there are one or two arguments that could be made that could give you some (if only a tiny, weeny amount) of reason to belief this is true.

The argument stems from the sheer improbability of our existence; as the infographic in an earlier section explains, from a mathematical point of view it's more than amazing that we are here at all – it's simply incomprehensibly strange. And if our universe is finite in nature, it seems ludicrous in the extreme to suggest we did arrive here by sheer random chance. More plausible alternatives, then, are an infinite universe, an infinite number of parallel universes, or …. a Creator.

The lack of any evidence other than the probability argument, though, is a real thorn in the side of this theory, and sheds some serious doubts about whether Heaven or Hell is what we might find ourselves waking up to after we die.

The Reincarnation Theory

You could argue the reincarnation theory is similar in some ways to the infinite universe and parallel universe theories, but here we are referring to the type of reincarnation that is central to Eastern religions such as Hinduism and Buddhism.

At the centre of Hinduism is a belief that every person on the planet has a Jiva, which is analogous to a soul and undergoes transformation in the cycle of births and deaths. So although we take different physical forms, our jiva, or soul, remains the same. The impact of your deeds throughout your life, the good or bad karma you accumulate, affects your jiva's standing and the type of body (whether animal, human or deity) you will take on in the next life. Once you have reached true enlightenment (a release from material desires), you are granted moksa (the final release).

This passage from the Bhagavad Gita (part of the Mahabharata, the ancient Sanskrit epic of ancient India) highlights the belief in an eternal soul and reincarnation so central to Hinduism:

"Never was there a time when I did not exist, nor you, nor all these kings; nor in the future shall any of us cease to be. As the embodied soul continuously passes, in this body, from childhood to youth to old age, the soul similarly passes into another body at death. A sober person is not bewildered by such a change. (2:12-13)"

Interestingly, the Hindu texts state that being trapped in the mortal realm, the endless cycle of reincarnation, is not the ideal plane of existence, in fact they state the opposite, that being on the mortal realm is a trap, a prison that encapsulates the soul until it realises the true nature of existence and completely abandons the ego and the lust for material goods and wealth.

True bliss, perfection, freedom, whatever you want to call it, is only achieved in the Hindu religion once you completely let go of the physical world, and it's at this point when you break free of the eternal cycle of rebirth and become something else entirely.

The 'Nothing' Theory

Finally, the obvious alternative to life after death. This is probably the most generally accepted theory among athiests, and the most likely scenario to the rational mind; the idea that once you die, that's it.

It fades to black, and you are completely unaware of anything else for the entire duration of the universe. You're gone forever. It might sound like the most cold and detached option, with no room for whimsical fantasies or pondering what might happen in the next life, but there are many who believe that eternal nothingness is the only thing that awaits all of us after our lives, and that the afterlife is such a simplistic, fanciful, self indulgent, human idea.

It's actually not hard at all to imagine nothingness - in the same way that you can't describe or remember anything that happened to you before you were born, once you die you experience exactly the same thing - pure nothingness.

It makes sense, but I would question the idea of even judging what we think we know about what happened before we were born. I think it's just as possible that there was something before we were born, and we either can't remember or can't comprehend it in our current form.

I mean, you can't remember what it was like to be in your mother's womb, as well, but does that mean it didn't happen?

The nothing theory may not be the sexiest theory, leaving little room for fascinating speculation or drug-fuelled discussion, but one thing it does have going for it is that it makes you realise just how precious and important your life here on Earth is now – if there's nothing at all after you die, if this is your only shot at existence, you better make the most of it and enjoy every second that you're here. Because once it's gone, that's it.

No second chances.

So, Which Is It? We'll (Probably) Never Know

We could argue about this topic all day, but will we ever really have a definitive answer for life after death? The universe could be even weirder than we could possibly think - we could be living in a simulation run by a small child who received a 'My-Little-Universe' universe simulator as a birthday present, we could be living in a dream, or, even stranger, maybe nobody else is real and you are the universe, and when you die, the universe dies with you.

Or perhaps the rapid pace of technological increase will mean that the question of the afterlife becomes simply irrelevant in the future; if we can develop ways to prevent or even reverse aging, and revive the body after sustaining a fatal wound, the question won't need to be asked – perhaps humans will simply life forever until the end of the universe, expanding out into every corner of the universe like a plague until it finally stops expanding and begins the process of shrinking into nothingness once again.

One final thing, though; I don't think you can definitely write off any of these possibilities as being correct or incorrect.

When you look at the bigger picture, the fact that I am sitting here at my computer, writing this article is bizarre enough in itself. The fact that any of us exist at all is simply remarkable. I think any one of these theories is possible, and the answer could yet be something stranger still – something our minds are literally incapable of grasping.

After all, our brains are merely the result of a few million years of evolution here on this planet, designed to cope with very primitive situations such as how to find food to sustain our fleshy bodies and how to find a mate to reproduce with – it was not designed to answer the universe's most complex questions.

Perhaps we're embarrassingly primitive in our questions of the universe; akin to a colony of bacteria in our body pondering there is anything beyond the confines of our comparatively colossal digestive system.

Until we die, or until such time as our technology and knowledge of the universe improves to the point where we can truly understand the incredibly complex structure of the universe, we will have to resort to pondering these questions with speculative awe.

photo credit: c@rljones via photopin cc
photo credit: Paul Anglada via photopin cc