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Hey Vsauce, Michael here and Derek
generate
78 that's so random. Or is it?
what does it mean to be random?
can anything really be random what's the most random thing ever?
today let's stop being random and become ransmart
if something is unpredictable
and contains no recognizable patterns we call it random
So let's begin our hunt for the most random thing with a coin toss
the Australian 50 cent coin is one of the largest coins
currently in circulation
coin flips and rolling dice are not intrinsically random
they are only random because of our
ignorance if we could know every initial condition
the exact forces and properties that play for a particular flip or roll
we could theoretically calculate the result before it
even happened and sure enough researchers have built coin flipping robots
that can precisely control a flip to get the result they want
100 percent of the time
so here is our question. Is there anything you couldn't predict
even if you knew everything? A process determined
by nothing and how can you be sure they're
aren't any patterns in what you're looking at maybe you just haven't looked
for the right pattern yet
or maybe you have already seen true randomness
but didn't know it because you didn't look for long enough
as if protected by a sort of camouflage
a random process can and will occasionally produce patterns
YouTube URL's are pretty much
random a unique one is made for every uploaded video but sometimes
like the proverbial monkeys typing away on typewriters
YouTube generates a URL that contains by chance a word
the official music video for 50 cents
in da club contains a synonym for bottom
this video was assigned hello
there are some sexies and a sauce. If you want to find out if a particular word
has been randomly assigned to a video yet you can search for it
by using this string in Google
the point is, randomness is difficult to identify it is easier to be certain that something
is not random than that it is. But despite this elusiveness is something interesting
is going on right now increasingly we
especially young people are calling clearly predictable
things random
like randomly running into your best friend at a popular restaurant
or hilariously bizarre combinations of things that we call
totally random because they are seemingly unrelated
even though of course they were chosen not in random but in a very determined way
because they are all unrelated
those guys that showed up at the party last night you didn't know
the weren't randos in a mathematical sense
they knew about the party, we're in the mood to go to a party and we're in the area
pretty predictable actually
this non statistical use of the word random annoys
some people but it's not that far off from the original meaning
of the word. In the 1300's random
meant running or at great speed
later it would be used to describe things that have no definite purpose
it wasn't until the 1800's that random took on a particular mathematical definition
then in the 1970's MIT's student paper
popularized the use of the word random to simply mean strange
of course just because something is strange doesn't mean it has
no discoverable cause why if we started calling so many predictable things
random well many theories revolve around
the amount up information and new people we are confronted with
at an increasing rate now more than ever before
perhaps it's just easier almost a bit of a relief
to call things random so that we can move on
to synthesize other information take a look at this die
now as you can see it rolls a five most of the time
but not all the time overtime
a sequence of its results will contain less randomness
but it is still random any face is possible and I have no guarantee beforehand
of knowing which face will show up the outcomes I'm selecting from make the
resulting sequence less full of
randomness but the process is still random
even though a die and a coin are extremely sensitive to their initial conditions
and over the course of normal use are quite
unpredictable they do over time
exhibit certain biases. Biases that make them
a bit more predictable and a little less random
than you might think. First of all dice even precision dice are only quality
controlled within a few micrometers
you can check this out yourself make
two stacks of ten or more similar dice
now if you orient each die every which way you should pretty much get two equally sized stacks
but if you arrange each stack
along a shared axis so that every die faces the same way
any regular imperfections caused by the manufacturing process maybe come visible
but what about coins?
well some fantastic research has been done on what happens when they spin
and flip. For instance it has been found that US nickel is just the right diameter and
thickness to wind up landing
not heads up for tails up when flipped but on its
side, about once every six thousand times it's flipped
but what about the fairness of flipping a coin well if you flip a coin like
this or statistical and physical reasons the side facing up
before the flip begins, doesn't actually have a fifty percent chance of being the result
instead as researchers at Stanford have found it actually has
a fifty one percent chance in this case it was the other side though
still pretty random. If you want a coin flip to be as fair as possible
you should just catch it in your hand. Don't allow it to hit the ground, bounce, tumble
and spin. That's because researchers have found that when a coin spins
larger biases come into play. The shape of it's edge
it's center of gravity. The heavier side tends to go down
quite often in the case of some coins as often as
eighty percent of the time. It's been found that a one euro coin
will spin and land heads up more often than not
and a US penny will land tails up
more often than not when spun. But like I said
earlier theoretically if we knew everything about the initial conditions
of a coin flip or a die roll we could
calculate beforehand their outcome
why don't we do that more often?
well it's extremely difficult
insane amounts of precision would be required because the smallest
difference between two initial conditions can be magnified overtime
leading to chaotic extremely difficult to predict results
random.org the service Derek and I used
beginning at this video to generate a random number uses
atmospheric noise. It's extremely hard to predict
but technically still a deterministic system
all that noise came from somewhere and if we could just find out those initial
conditions we could
theoretically predict their outcomes
if we want a system more random
than that we will need to find one that is determined by nothing
and for that let's look closer. Quantumly close
quantum mechanics may have our answer
it describes the properties of quantumly sized things
as probabilities
just chances, not because we don't know enough yet to be certain
or predict but because, well the idea is
there's nothing there to predict
there is no beforehand we could know
whether or not a particular individual radioactive atom will decay or not
or whatever the spin of an electron is
is only knowable once we look. They're determined by a deep-seated
randomness woven into the universe itself
Einstein couldn't believe this he refused to accept as he said
that God played dice with the universe
but experiments
with entangled particles have shown
violations of Bell inequalities
entangled particles are particles that exhibit similar properties
even with separated by large distances
now if they agreed on those shared properties to have or are somehow
determined beforehand to have them their behaviors
should satisfy bells famous inequalities but experiments have found
that instead the likelihood of what a machine will see when measuring one particle
determines how the other machine will measure the other particle
it is here, when we look that the chance is determined. Explanations for this
are even weirder but what the results suggest is that
the chance of seeing particular quantum qualities
don't pre-exist
they happen when you look
so if you are ever feeling boring or
predictable just remember that you are made out of octillions
of quantum probabilities. Dice that don't tumble in any
analyzable way we could ever predict
they are the most random thing
God may play dice with the universe but they are
the best dice in the universe
and as always thanks for watching
but what does it all mean?
well true randomness doesn't mean anything I mean for us to have meaning we need
structure, predictability and that is what I'm exploring over on my channel, Veritasium
Wow okay so
let's go over there and take a look at what is
not random. Veritasium let's go
I'll see you guys over there. It's going to be awesome come with us
and as always
thanks for watching