The Universe isn't Real??

On October 4th, our land aspect John

Clauser and Anton Zeilinger were awarded

the Nobel Prize in Physics for proving

that the Universe isn't locally real

what I love about this story is that

it's a story of quite literally some of

the most intelligent people who have ever lived

being confused and how, ultimately

Einstein was proven wrong, which doesn't

happen all that often. That idea

of locally authentic is made up of two

concepts locality is the idea that

things are only affected by their local

environment, you can't flick a switch in

another galaxy hundreds of light years

away and instantly see the results here

because nothing, not even information, can

travel faster than light realness though

is much harder to explain, and that is

the focus of the Nobel Prize

foreign

close to the beginning of the 1930s

where there were two paradigms, two ways

of thinking about the physics of small

things like particles, atoms electrons

photons Etc the view of Einstein, and

many others, was that the Universe is

real the particles, atoms, and electrons

have definite properties that are

inherent to them regardless of if they

are being measured essentially the if a

tree falls in the forest, and no one is

around to hear it, it does make a

noise, and then there was a counter group

The anti-realists championed by people

like Bohr, as well as many others the

particles have properties that haven't

made up their minds until you

go out and measure them that

they exist in a wave function of

possible States, and only when you

take a measurement. Do they

really make up their minds, the famous

example here is that of Schrodinger's

cat that is both alive and dead until

you look in the box and then, ultimately

you go to prison foreign

Culminated in a famous paper called the

EPR paper where Einstein, Podolsky and

Rosen put forward a thought experiment

that they thought perfectly highlighted

quantum mechanics, at best, was

incomplete and, at worst, may be totally

wrong their thought experiment focused

on an idea in quantum mechanics called

Entanglement that the property of two

particles can be inherently related

their line of reasoning for their

thought experiment started with well we

know that energy is conserved, things

don't suddenly start moving in a

direction unless someone or something

pushes or pulls them, neither also do

they suddenly start spinning rotating

jumping up and down or doing anything

else unless someone else is directly

affecting them number two if we start

with a small quantum mechanical particle

that isn't spinning, moving, or doing

anything else, let's imagine that

particle spontaneously breaks into two

if we look at one one of those pieces it

breaks into and finds that it's moving to

the right, we know instantly that the

other particles must be moving to the

left to conserve momentum, or if we had

looked at it and found that it was

spinning one way, maybe clockwise we

would know instantly that the other

the particle must be spinning

counterclockwise to conserve angular

momentum, you'd be confused if you looked

at this system and saw both particles

suddenly moving to the right, your

intuition would tell you that some

outside force maybe must have hit them

or for the same reason, though, maybe

less intuitively because most people

don't think about angular momentum or

spin, you'd be equally surprised if you

saw both particles rotating in the same

direction, you'd assume that something

must have hit them and caused them both

to start spinning step 3, quantum

mechanics here says these states are

impossible to know before you go out and

measure them if you separate these

particles light years apart and measured

one day and found that it was spinning

clockwise you'd know instantly, even if

that particle was a universal way a that

its counterpart must be spinning

counterclockwise, but how could this be

if they only take on a definite

value when you measure them and the

other one always needs to be the

opposite of what you've measured, then

the particle that you did measure would

need to communicate instantaneously

its partner and tell it to adopt the

opposite value permanently Einstein

argued that this was impossible because

it would have violated locality and

meant that information had travelled

instantly faster than the speed of light

to tell the other particle to collapse

its wave function and make up its mind

which way it was spinning, he instead

argued it must have made up his mind at

the very beginning when it was created

we didn't know it, or we weren't

smart enough yet to find a good way of

measuring it, he called this unknown

knowledge of hidden variables and said that

this was the piece in quantum mechanics

that was yet to be completed, and for

around 30 years, physicists really kind

of splitting into two groups, either they

sided with Einstein, or they sided with

cool, mainly because no one had really

come up with an excellent theoretical or

experimental counterargument to

Einstein's EPR paper

that was until about 1964, when John Bell

an Irish physicist on sabbatical from

working at CERN started to do some more

theoretical work of his own these Works

which were later called Bell's theorem

or Bell's inequalities which there

are many different forms but the

the underlying idea is to try and get the

universe to pick a side tell us whether

those hidden variables and Einstein's

right or tell us whether truly there is

a wave function, and that quantum

mechanics is real now. This hinges a lot

on what happens to Quantum objects when

you go out and measure them so

let me introduce you to the idea for a

a particle of light called a photon

photons have a property called

polarization which describes which way

the wave of light is oscillating through

space either vertically or horizontally

or potentially somewhere in between if

you wanted to measure which state a

photon was in, you would put it through a

polarizer that lets through either

vertical light in one orientation, or it

will only let through Horizon's gentle

light in another orientation but then at

At least your detector, which you place

behind that, polarizer knows what sort of

light, it detects if you fired in

randomly polarized light, some of it

vertical, some of it horizontal, some of

it in between by placing a vertical

polarizer first, then a horizontal

polarizer after you would expect

correctly to see that no light reached

your detector because all polarization

angles had been blocked. You can see this

effect when using polarizing films which

are the same stuff you find on a pair of

polarizing Sunglasses by orienting two

polarizing films at 90 degrees to each

other you see no light emerges through

them. What is interesting here is that if

you place a third polarizer between

these two you suddenly and I think, quite

counter-intuitively start to see more

light this is because fundamentally

measuring a particle changes its state

allowing light to slip through the final

polarizer where usually it wouldn't be

able to so you start to see more light

than you would otherwise expect, so let's

jump back through into the story at this

point in history, Belle's work was still

more Theory and thought experiments than

anything else, and that classically is

the problem with theoreticians is that if you

look at them from a distance. It just

It looks like a wizard trying to have an

argument with you

physicists needed to find a way

of actually completing an experimental

measurement

one of the early and most elegant and

now heavily evidenced extensions of

Belle's theorem work is the CHSH

inequality by John Clauser, the Nobel

Prize winner that we're talking about

here Michael Horn Abner shimini and

Richard Holt and their work here makes

this theorem that Bell developed

actually experimentally testable the

scenario they describe is similar to what

we've talked about two entangled

photons are sent in opposite directions

to Two observers, Alice and Bob. Both Bob

and Alice gets a polarizer to play with

into their setup that helps them

determine which polarization the light

is actually in, and finally, Alice and or

Bob, at random, is told to rotate their

polarizers over time and record where

the photons arrive successfully or not

at their detectors, what we're interested

in doing here is counting how frequently

that Alice and Bob agree on whether

they've seen or not seen a photon

if Alice and Bob perfectly anti-aligned

their polarizers, then they should always

both either see a photon or neither one

should see a photon, they should always

agree on whether photons arrived or

photons didn't arrive

if, however, Alice and Bob both align

their polarizers either Alice should see

a photon, and Bob shouldn't see one or

Bob should see a photon, and Alice

shouldn't see. The interesting parts

happens at angles between these

positions if the Universe is real and

photons are truly independent Alice and

Bob's rate of agreement should linearly

move between full agreement and full

disagreement

If, however, the Universe is not real we

should expect to see a higher rate of

coincidence than otherwise expected, just

like in our three polarizer setups, except

now our polarizers are on the other side

of the Universe from each other and the

same Photon isn't going through both or

is it this can only be true if the

particles are really still connected to

let each other know which polarization

state to be in so that measurement on

one indeed does affect the measure on the

other, and in 1972, it was John Clauser

who built the first experimental setup

capable of conducting this measurement

in the paper that he released that year

this was the figure that he displayed

exactly matching the prediction of

quantum mechanics proving that the Universe isn't locally real that

Einstein's deterministic view was

incorrect, and a story from this point

goes, I'm not sure if it happened

or not that excited by proving the

result clause runs into Richard

feynman's office to tell him the news

and in classic Feynman fashion Feynman

throws him out of his office forever

doubting quantum mechanics and tells him

good, now get on with some real physics

the other Nobel Prize recipient, Elaine

aspect, and Anton Zollinger closed

significant loopholes that remained within

this experiment as well as showing that

quantum entanglement can be transferred

to other particles in a process called

quantum teleportation, all this to say

that without a doubt, the Universe showed

itself to be Stranger Than even Einstein

had imagined

All of these phenomena are the

backbone of what is driving the modern

Quantum Computing Revolution is the idea

that at some point in the hopefully near

future quantum computers will outperform

classical computers because they have

this inherent baked-in advantage that

down at their core, the particles that

run them are communicating with each other

while this doesn't prove and I can

forgive anyone for on first

hearing thinking that people can now

communicate faster than light although

it would be possible to derive some fast

and light Communication that

unfortunately is where the field pretty

unanimously says no, this is ultimately

because the core of this phenomenon is

inherent Randomness at the source of

that Photon or entangled particle

generation and then also at those

measurement Points, each Photon will

either make it or not make it through a

polarizer, each Photon will either be

created in some combination of states

that ultimately those combinations of

conditions will be impossible to know until

measured, there's no way of loading

information onto that Communication

channel, and as a result, there is no way

of violating Einstein's fundamental

contribution, which is that the speed of

light is a fundamental limit in the

universe that stands correct

and I think Keith and Einstein would be

reasonably happy about that

REFERENCES:

Donald DeMarco. "Fetal Pain: Real or Relative?" 2007, https://www.lifeissues.net/writers/dem/dem_06fetalpain.html.