Hey, Vsauce. Michael here. If you threw
every single human alive today into the Grand Canyon,
we would not fill it up.
We could make a pile about this big
That's it. That's all of us. All 7.159 billion of us
in one place. A species
portrait. It kinda puts humanity into perspective
and you. So does this. Everyday you produce about one to two litres
of spit, which means, in your entire lifetime
altogether, you will not produce enough spit
to fill an Olympic-size swimming pool.
So far, 560 billion Lego parts
have been manufactured and the total number of grains
of sand on Earth is estimated to be 7.5 times 10
to the 18th. But here's the thing:
how many things are there... total?
Well, how do you define a thing? Well, let's say it's a thing
if you can think about it or talk about it. If you can call it a thing,
it's a thing. This is going to be a lot of things.
Things can be real, imaginary,
impossible, ideas are things, things can be looked forward to and things can be in the past
or yellow or concrete or abstract things can
happen and some thing's probably won't.
Making a video about how many things there are.
That's a thing... that I'm doing right now.
Let's count everything.
Right away, the answer seems obvious. The word
'thing' is so vague, the answer is clearly infinite...
possibly... not.
All we have to do is take the maximum number of physical things,
things out there in the real world, beyond our minds we could
in theory measure and add to that the total number of things we
could imagine. The total number of thoughts possible.
For the purposes of this video let's assume that numbers and math
and the laws of physics exist as part of the way
our universe is. But the names and representations they've been given
are the products of thinking minds and those things
are, well, things that we can count.
And there's no reason to double count. All of the indivisible
pieces that make up me, particles or strings or whatever
are the same as the thing that has been named me.
Abraham Lincoln has a great quote about this.
"How many legs does a sheep have if you call
its tail a leg?"
Four.
Because calling a tail a leg doesn't make it one.
Okay, let's begin. When counting the number of
physical things in the universe we hit an unknown.
How big is the universe?
The entire universe could be infinite
or it could be finite, but edgeless for a variety of reasons. There could also be
other universes. But it's unclear whether we'll ever be able to actually see all these
things. Instead, what we are stuck with, and what we usually mean when we say
'the universe', is the observable universe
whose future visibility limit has been estimated to be only 62
billion light-years in any direction.
That's it. This is likely the only inventoryable space we'll ever need
to worry about. And it contains roughly,
on average, ten to the eighty elementary particles. Particles with no
further internal parts as far as we currently now.
So that's our answer, right? There are ten to the eighty
physical things that exist out there, beyond our own minds.
Any other physical thing - water, dogs, planets,
saxophones - are just names given to particular arrangements of those same
ten to the eighty particles. But wait, what if,
in the future, we discover that what we call elementary particles today
are actually just made out of smaller things we should have counted
instead? Well, to cover ourselves let's count
the maximum possible number of the smallest measurable thing.
Something the size of a Planck volume.
10 to the power of 183
things that small could fit within our observable universe.
I like this number, 10 to the power of 183.
You couldn't easily argue there were more things than that
in the physical, real-world. But you could imagine.
A Planck length, a Planck volume. That's just
the smallest measurable amount of space, not the smallest
possible. You could imagine a
half Planck volume, a 10,000th of a Planck volume.
But, that would just be a thought and only ever
a thought. So, how many possible thoughts
are there? It's probably safe to say that the number of possible
thoughts is, indeed, infinite. For example,
numbers. You can't say there's a limit to the biggest number we can imagine.
But, unlike physical things that exist whether or not we have
discovered them, do unthought thoughts
already exist? It seems more like the pool of possible
thoughts is really just one thing an actual elements from that set don't
become things by themselves until we thing them
that is we or some other mind thinks about them
or talks about them and there's a limit to how many things
we or anything else could ever thing
our observable universe is only so big and it will contain usable energy
for only so long. After about 1 trillion to a hundred trillion years
the supply of gas needed to form new stars will be
exhausted and the lights will start going out
one-star at a time. After a
Google years the amount of usable energy left in the universe will be
0 and nothing will be able to happen
to calculate the maximum number up thoughts that could be
thought inside our observable universe let's take
all of its mass and turn it into human brains
that just think new and random thoughts from the beginning of time
until the universe runs out of usable energy, a Google years
of thinking. But wait, what if there are
alien brains or for all we know Earthling brains that
think faster than we can okay well to be safe
let's not turn all of that mass into human brains let's use it to build a
giant hypothetical machine that computes at the fastest speed possible given the
speed of light
in the uncertainty principle; Bremermann's Limit
its 1.36 times ten to the fifty bits per second per kilogram
of material, now a high-end estimate for the total mass of the observable universe
is 3.4 times ten to the the 60 kilograms
which used exclusively for the best possible computing machine could altogether
process 4.624 times ten to the 110
bits per second. Now with 3.154 times 10 to the 116
seconds available from the beginning of time to the heat death of the universe
and an assumption that the average thought takes about a sentance worth
of information to describe
say about 800 bits we get a total
of 1.458 times
ten to the 227 things that could
ever be thought or imagined. That number
is huge. In the observable universe
the universe as we will ever know it the number of thoughts that can be thought
is so much larger than the number of physical things there can be with out
imagination and if you were to combine the two totals
the number of physical things would barely
make a difference. So, funny enough
when it comes to every thing in the universe
it really is the thought that counts.
And as always,
thanks for watching.