Category
😹
FunTranscript
00:00 In many ways, you are amazing.
00:03 You're a complex and unique bundle of cells to make the bones and muscles and organs that
00:08 form your body, and also to build and fuel the single most impressive thing you have
00:12 - your brain.
00:14 But still, from some loftier perspective, you're actually not that great, or interesting,
00:21 or special at all.
00:22 On the cosmological scale, human life is but a tiny fleck on an endless and unfathomable
00:28 landscape.
00:29 And that's pretty daunting, but also quite inspiring.
00:33 This is Unveiled, and today we're answering the extraordinary question; what's the purpose
00:38 of the universe?
00:41 Do you need the big questions answered?
00:43 Are you constantly curious?
00:44 Then why not subscribe to Unveiled for more clips like this one?
00:47 And ring the bell for more thought-provoking content!
00:51 What is the universe, really?
00:53 From a purely physical point of view, it's reasonably simple.
00:56 It's matter.
00:57 Lots and lots and lots of matter.
01:00 Some that gets clumped together, some that gets stretched out.
01:03 And all of it moving around and through space, all of the time, at variously immense speeds.
01:08 Thankfully, in terms of us even beginning to understand it all, that matter does at
01:12 least form some recognisable shapes and structures.
01:16 Galaxies are comprised of planetary systems, which involve an indeterminate number of planets
01:20 orbiting around a star.
01:22 Perhaps two stars, maybe more than two stars.
01:25 Planets are joined by other astronomical entities like asteroids, occasionally black holes,
01:31 quasars, magnetars, etc, etc.
01:34 And all of the endless stuff combined is made up of rock, ice and gas.
01:38 Of minerals and elements.
01:40 Of molecules, atoms and subatomic particles.
01:43 But clearly the question of what is the universe can take us in different directions as well,
01:48 and towards some of the deepest and greatest mysteries of all time.
01:52 That can lead us to ask further questions, like what's it all for?
01:55 Why does any of it matter in a non-physical sense?
01:59 And why are we here to even think these thoughts about the universe in the first place?
02:03 The theory of cosmological natural selection was devised by the American theoretical physicist
02:08 Lee Smolin in the 1990s.
02:11 Smolin built the idea in the early part of the decade, before setting it out in full
02:15 in his 1997 book, The Life of the Cosmos.
02:18 It's a theory that suggests pretty much exactly what it sounds like - that the universe
02:23 is the way it is because it's been honed and perfected to be that way.
02:27 Away from cosmology, natural selection is the evolutionary process through which life
02:32 adapts and grows to give itself the best chance of survival.
02:35 What Smolin proposes, then, is that the universe behaves in the same way.
02:40 As part of regular natural selection, however, there are inevitably lifeforms that don't
02:44 make it, that don't change enough or in time, and as a result they die off and disappear.
02:50 So, how would that work in cosmological natural selection?
02:53 Two words.
02:55 Black holes.
02:57 At the heart of Smolin's theory is the suggestion that black holes act as a kind of facilitator
03:01 for multiple universes, including this one.
03:04 It's said that a collapsing black hole is actually a birthing point for a new universe,
03:09 which then emerges from the other side of that black hole.
03:13 The theory argues, then, that any one universe is capable of reproducing as many new universes
03:18 as there are black holes within it.
03:20 What's incredible is that, for our universe, that would mean that it has the potential
03:24 to generate upwards of forty trillion new universes - going by just the more conservative
03:30 estimates as to how many black holes there are.
03:33 If we were to assume that our universe itself was also born out of a similar arrangement,
03:38 and that that setup were to repeat over and over and over again, then we very quickly
03:43 weave an incredibly intricate mesh of endlessly recalibrating matter - otherwise known as
03:48 the true nature and structure of reality.
03:52 Cosmological natural selection isn't without its pitfalls, however.
03:55 And as clean and satisfying as it may all appear at first, many physicists have taken
04:00 issue with one key element to it.
04:02 The theory relies on there being some form of information transfer between the universe
04:07 that's hosting a black hole - the parent - and the universe that the black hole creates
04:11 - the baby.
04:12 For there to really be any kind of selection at play, there has to be reproduction, mutation,
04:18 and some level of learning happening within the black hole.
04:22 But nothing we know of would indicate that that is the case.
04:25 As a standalone claim, then, the idea that black holes could double up as effective universe
04:29 factories just doesn't hold up.
04:32 Although, more broadly, black hole cosmology does endure as a wider, more general framework,
04:38 proposing that our universe could still exist within a black hole.
04:42 For as long as only part of it is observable, while the rest remains unobservable, there
04:47 might always be an argument that this could be the case.
04:51 One thing that cosmological natural selection does provide, to a point, is a purpose.
04:56 If the universe really does exist within the model it lays out, then there seemingly is
05:01 a kind of end goal to aim for.
05:03 As it pulses its way through the endless stream of potential universes, we can imagine that
05:08 reality is really always striving for the perfect one.
05:12 Whether or not this universe is that perfect rendition is probably impossible to tell from
05:16 our lowly perspective.
05:18 However, there are hints toward it being a pretty effective attempt at a universe, at
05:22 least - such as the fine-tuning problem.
05:26 This is the much-debated concept that asks, "Why does this universe apparently work
05:30 so particularly well?"
05:32 We have certain fundamental conditions, such as the nature of gravity, of electromagnetism,
05:37 and the structure of atoms, that if changed even a tiny way would otherwise render our
05:42 universe impossible.
05:44 If we see the universe that we know of as simply the product of natural selection, however,
05:48 then it begins to make sense as to why all of those things exist as they do.
05:53 Across all of the other universes until this point, the balance was never quite correct.
05:58 But here, it's just right.
06:00 But still, just right… for what?
06:03 Usually we think of the finely-tuned universe as being the one - this one - that allows
06:07 for life on Earth, or life as we know it.
06:10 But can we ever be sure that life is what a universe - any universe - would want to
06:15 happen?
06:16 For more on this pretty ominous existential question in particular, be sure to check out
06:20 our other recent video.
06:22 But for now, it's a question that serves to further highlight just how unknowable the
06:27 true power, scale and purpose of the universe really is.
06:31 Because consider for a moment that life actually isn't part of what the perfect universe
06:35 would be.
06:36 What would that then mean for us?
06:38 If multiple universes really were possible - and especially if they're possible via
06:42 cosmological natural selection - then that would mean that we are inescapably doomed.
06:47 And not only doomed from this universe, but also from all other successful universes that
06:52 this one ultimately gives rise to.
06:55 And suddenly the fine-tuning problem actually isn't much of a problem at all.
06:59 Because in this case, the universe got it wrong, not right.
07:02 And all that we know is really just one of trillions of try-agains that ultimately get
07:07 consigned to the cosmological scrapheap.
07:10 Statistically speaking, it's much more likely than not.
07:14 But of course, no one can yet claim to definitely know the true matter of things.
07:18 If they did and they could, then they'd basically be a god.
07:22 And there are various arguments that humankind has the concept of god in order to directly
07:27 combat many of the great unknowns that we've touched upon in this video.
07:31 Clearly, there are some aspects to reality - to our conscious experience - that defy
07:36 anything even close to a simple explanation.
07:39 And so, god provides a kind of catch-all safety net for anything that we don't or can't
07:45 understand.
07:46 But, even with god or gods to fall back on, perhaps the same questions still apply.
07:52 Even if a god were to exist, and even if they did create the universe, then why?
07:59 Let us know what you think in the comments.
08:01 Do you think we can ever hope to have a clear answer to something as immense as this?
08:06 Should we even want to have a clear answer?
08:08 For some, the pondering of higher mysteries is all a part of life in itself.
08:14 For others, the quest for answers is one that we all should be on.
08:18 Into which camp do you fall?
08:20 The debate certainly doesn't begin or end with only cosmological natural selection,
08:26 or black hole cosmology.
08:28 It represents just one direction we could head down in a search of knowledge and clarity.
08:33 But for now, it does paint a compelling picture of what the true purpose of the universe might
08:38 be.
08:39 What do you think?
08:40 Is there anything we missed?
08:41 Let us know in the comments.
08:43 Check out these other clips from Unveiled, and make sure you subscribe and ring the bell
08:47 for our latest content.