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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

Hey Vsauce, Michael here and Derek

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B1 US random coin randomness predict flip predictable

What is Random?

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    Tu Howard posted on 2014/09/27
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