quantum physics, reality, and you

8/8/2019 Quantum Physics, Reality, And You

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Jenny Nielsen

UMKC

2009


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Intro

Quantum means tiny piece. Quantum

physics is the study of the little pieces of

matter you andI

and everything else ismade of. It is the study of reality at its most

basic level.


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Quantum Bi-Location

First off, an electron is a little piece of matter

like the tiniest baseball you can think of.

Lets aim a tiny baseball at two holes so

The ball will go through one hole or the other.

The ball will leave a bullet hole mark

on a screen on the other side of the holes

to show us which hole it went through.

But wait. The baseball is creating a strange

pattern, as if the ball has gone through

both holes at once HUH?


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Wait just a second, here.

Wait how does THAT work?

Lets put a detector at each hole so

we can watch how this is happening,

While its happening.

Oh dear!

Now the electron only goes through one hole at a time.

No interference pattern shows up. Each ball leaves one

bullet hole in the screen.

They behave differently when we are

watching, folks. And by the way, this works with photons, atoms, and large molecules, too.


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http://abyss.uoregon.edu/~js/21st_century_science/lectures/lec13.html

W

atched (one hole at a time)

Not Watched (both holes at once)

Double Slit Experiment


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Delayed Choice Experiment What if someone sets up detectors to check

JUST AFTER the particle decides which holeto go through, but before it makes the bulletpattern on the other end? Can we watch the

bilocation now?


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Delayed Choice Experiment

The particle will still go through only one

door when were watching live, even if we

turn on the cameras just after it makes its

choice. It is as if the electron knows we

are going to look.

But, if we dont turn the detector on, they

still leave the interference pattern on the

bullet screen as if they went through both

paths at once.


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Schrdingers Cat* What if we rigged up an experiment so that a cat dies if the particle

goes through one hole and lives if the particle goes through the

other hole? If were not looking, is the cat be both alive and dead at

the same time?

*Note: This is not standard Schrodingers Cat, but gives the basic idea.


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Quantum tunneling

In the atom, electrons exist as

probabilities. The electron pops up at

different places in the atom each time you

look. Electrons can even jump through

solid walls every now and then just

because there is a chance they will do it.


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Wait. It gets weirder.

Particles in close contact often become

entangled.

For example: take two electrons from thesame orbital in the same atom. These

electrons are entangled in their spins.


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When one spin-entangled particle is spin

up, the other entangled particle is spin

down. Always. Like a really bad marriage.


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If an electron falls in the forest

But particles dont seem to take on solid properties until

you look at them. When youre not looking, they seem to

change their properties randomly back and forth at all

times. Its as if they are in two states at once.


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More Entanglement

Lets call two particles Mrs. Pacman and

Mrs. Kirby. Theyre best friends, from the

same atom house, and entangled.

When we look at Mrs. Kirby, she will

decide if she is spin up, or spin down.

Lets check on her now.


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Entanglement


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When Mrs. Kirby is spin up, Mrs.

Pacman IMMEDIATELY becomes spin

down.

Instantaneously.

NO MATTER HOW FAR AWAY

PACMAN IS FROM KIRBY.

We can separate them by miles and

miles and the experiment comes out

the same.

They must be connected outside of

time and space.


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Still weirder.

Particles at one time can be entangled with particles at

another time. We can show this in a lab.

We cant use this behavior to send instant signals, or

signals back in time, because quantum messages arealways random. If we force particles to be spin up or

down, the entanglement goes away.

We can use it to enhance regular communication, but

thats another story.


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Quantum Physics, Reality, and

YOU Everything in the universe is connected instantaneously witheverything else.

Your brain runs on electrons hopping through pathways.

Your brain might run on quantum physics.

Particles in your brain might be entangled with other particles in yourbrain.

Particles in your brain might be entangled with particles in other

brains.

We might all behave like quantum particles and be biochemically

programmed not to realize it. We might exist in more than one universe at a time.

At least on a teeny tiny level, the past might be affected by the

future, or cause and effect doesnt matter at all.

At its most basic level, reality changes when you look at it.

Our bodies are made out of these things.

quantum physics, reality, and you

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