When we look at the universe, we tend to take for granted how it all just seems
to work. From the cosmic scale all the way down to the smallest fundamental particles,
it all seems to exist just fine. There are no glitches in the matrix, and nothing deviates
from what is described by physics. It works so well, in fact, that life can exist and never
really worry about why things work the way they do. But when we stop and think for a minute about
the particular way in which the universe is set up, some wonderfully strange questions are raised.
If there’s one thing we can know for certain, it’s that ours is the only planet in the
universe known to support life. Everywhere we look, whether it’s on the tallest mountains
or the deepest points in the ocean, there’s almost bound to be some creature living there,
and thriving in the most extreme conditions. Perhaps even more surprising is the existence
of intelligent life, whether we’re talking about humans, or other higher animals like
primates and dolphins. Our planet seems to be a haven for life in an otherwise endless,
black void that is the universe. It does make you wonder, how did life even come to exist?
Is it just a massive cosmic coincidence, or is there something bigger happening?
We have established that life exists. Congratulations, Nobel Prize for us.
This means that the universe must be set up in a way that allows for life to be
possible in the first place. This makes sense, because if the universe didn’t allow for life,
then we wouldn’t be here asking these questions. But when you think about it, this seems rather
odd. There are an infinite number of ways in which the universe could have been different,
resulting in different physical constants. So why should the universe happen to have the ones
which allow for life? Could it be possible that the universe was specifically set up for us?
Our best theories for describing the universe are currently the standard model and general
relativity. The standard model describes three fundamental forces; the strong, weak, and
electromagnetic forces, whereas general relativity describes the fourth; gravity. When talking about
the universe at the grandest scale, all that really matters is gravity. Even though the
other forces are much stronger than gravity (the electromagnetic force being 1036 times stronger),
their influence only extends to the nucleus of an atom. This is why when you split an atom,
it tends to result in something like this [bomb]. When it comes to the dick measuring contest on
the universal scale, gravity will always win. This is where things start to get interesting.
If gravity had been absent or significantly weaker, then no planets, stars, or galaxies
could have formed in the first place. Even if gravity had been only slightly weaker,
the stars would have been much colder, and wouldn’t have formed any heavier elements such
as the carbon and oxygen needed for life. On the other hand, if gravity had been any stronger, the
stars would have formed much smaller, and be much shorter lived. A similar situation arises with the
nuclear strong force. If it was any weaker, the stars wouldn’t have formed anything heavier than
hydrogen; the lightest element in the universe, and if it was any stronger, then all hydrogen
would have burned away many billions of years ago. A change in the strong force by as little
as 1% in either direction would have resulted in a universe without any of the life that we
know and take for granted on the Earth today. Some scientists argue that not only are these
forces fine-tuned for life in their strength, but also in regard to the forces themselves. Both
gravity, strong force, and electromagnetism are essential for the creation of complex molecules
such as DNA. In a universe that doesn’t contain all of these forces, it’s unlikely that life would
have a chance to form. It’s quite hard for life to get started when gravity is so strong that the
universe collapses back in on itself, believe it or not. But mystiverse, I hear you cry,
if the universe were any different, we wouldn’t be here to ask questions about it. Of course the
universe seems fine-tuned for life on account of us being here in the first place. But,
as we’re about to see, physics isn’t the only thing that seems to be fine-tuned for life.
As well as physical constants allowing for life, there's also evidence of fine-tuning in biology.
In order to survive, an animal depends upon sight, for instance, to avoid potential dangers and find
a mate. However, this sight also depends upon the functioning of their eyes, brain,
and all the complex networks in between. Many scientists nowadays would call upon Darwinian
evolution to explain this; sight works thanks to evolution by natural selection over many thousands
of generations to arrive at where we are today. However, recent findings have indicated that the
situation might not be as simple as it seems, and that more is going on behind the scenes.
Some researchers argue that there are fine-tuned features of organisms
that could never have come about through Darwinian evolution. For example, bacteria
sometimes have what is called a flagellum; a structure that allows them to swim about
watery environments, as well as sense chemicals and temperature outside the bacterium itself.
Nice word innit, flagellum.
The researchers argue that the flagellum is irreducibly complex, meaning that it could
not have come about from the small-step changes involved with natural selection. The same is often
said about the eyes; with so many complicated parts and specific reactions that have to occur,
this seems like another instance that’s impossible to explain. Other researchers
have taken this one step further. Some have argued that the evolutionary steps
hypothesized by Darwinism are so improbable that we couldn’t expect them to occur even
once in the entire history of the universe. It seems like we have reached a bizarre conclusion.
There is an impossibly large number of ways in which the universe could have been different,
and in most of them, the possibility for life is next to zero. The overwhelming
probability tells us that the universe should not have contained life, and yet
here we are. So why does the universe happen to have just the right conditions for life?
There have been many different answers to this question throughout time,
but perhaps the most common have been intelligent design. The classic response to fine-tuning is to
infer the existence of some cosmic designer, who monkeyed around with physics until the universe
had life-friendly conditions. One of the most famous design arguments comes from William Paley,
and the watchmaker argument. Imagine walking across a field, and coming across a stone. For
all we know, the stone may well have been there forever. But suppose you carried on walking and
came across a watch. We wouldn’t have the same answer before, because at some point we know the
watch must have been designed. It must have been built, and someone must have designed its use.
For Paley, the same reason we know the watch had been designed is the same reason we know that the
universe must have been designed. We can tell that the universe must have been built,
and designed with a specific purpose. The only difference between the two is that the universe
is far more magnificent than the watch, and therefore must have been created by a far more
magnificent designer. The complex nature of living things right down to the smallest detail suggests
intelligent design. For theists, the fine-tuned universe suggests that not only does God exist,
but He created a universe which is perfectly suited for life to flourish,
and this is the universe we are living in now. However, as science progressed, and we better
understood the world, new theories were suggested, and ones that were even stranger.
The main alternative to intelligent design is the multiverse hypothesis. According to this theory,
our universe is one of multiple other universes, or perhaps infinitely more universes. Some of
them are only slightly different, whereas others are radically so. If we assume that
there are infinitely many other universes, with infinitely different physical conditions, then
it makes sense that all these universes together make up everything that possibly exists. If this
really is the case, then it’s likely that at least one of these universes should contain the right
conditions for life. Since we are alive in this universe, this means our one has those conditions.
The multiverse hypothesis provides a convincing explanation as to why our universe should have
the right conditions for life. If we assume that the multiverse is diverse enough, it wouldn’t be
that surprising that there is at least one which provides the right conditions for life, or that we
happen to exist in one of the life-friendly ones. Some atheists might argue that the multiverse
hypothesis can explain fine-tuning without the need for intelligent design, so it can replace
God as an explanation. However, this doesn’t really work. Neither God nor the multiverse
are things that science can verify, and so we are left to wonder. Is it merely a coincidence
that we are here, and that the universe is so well prepared for our arrival? Or is there
something bigger at work, and either God or the multiverse has contrived to make life possible?
These are massive questions, and ones where the answers might remain forever out of our reach.
Whatever the answers might be, the fact of the matter is that you exist in a universe in which
life is possible, and that’s a pretty incredible thing. So many things must have happened in order
for you to even be here. In the vast number of possible universes that went wrong, you are
fortunate enough to exist in the one that went right. Even after the low probability that our
universe even existed at all, the chances of you actually being born into it are next to nothing.
When you take into account the chance of your parents meeting each other, the chance that one
specific sperm cell successfully fuses with one specific egg cell, the chance that every one of
your ancestors up to this point has successfully reproduced, and then you successfully being born?
The probability works out at something like 1 in 400 trillion. Pretty lucky if you ask me.
The universe is like a massive watch, and whether it was God or pure mathematics that created it,
all the little parts were undeniably created to work in harmony. There’s a rhythm in everything,
and your existence is proof of that fact. Just like you depend upon that rhythm to keep you
alive, the rhythm depends upon you as well. The universe is most definitely fine-tuned
for our existence. Perhaps more importantly, we are fine-tuned to the universe we find
ourselves living in, and that is nothing short of a miracle. So go on! Do stuff,
be something, because if the universe were any different, you wouldn’t be here at all. If you
enjoyed this video, the like and subscribe buttons are fine-tuned to be pressed as well.
Thank you very much for watching, peace and love, and I’ll see you in the next video.