The Many Worlds of the Quantum Multiverse

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The Copenhagen interpretation of quantum mechanics tells us that observation collapses a probability wave into a single definitive outcome, but this isn’t the only interpretation of quantum mechanics. The many worlds theory proposes that the wavefunction never actually collapses. The observer simply follows one of those many possible paths into their present reality while all the other paths continue on independent of the observer. Each of these paths branches off into an entirely different reality. In this episode Matt discusses the details of the many worlds theory and why it’s not so far-fetched to think that our reality is simply one of an infinite number of realities existing within space time.

Links to sources:

The Quantum Experiment that Broke Reality

Hugh Everett's Ph.D. Dissertation

Crazy Pool Vortex

Previous Episode

Written and hosted by Matt O’Dowd
Produced by Rusty Ward

[Agent.Logic_]

Good to know that there's another me out there in another multiverse who fully understands this video.

[PunkMonster]

One highly confused physicist out there in the multiverse who did the double-split experiment and got a smiley face on the wall.

[theCodyReeder]

Insane way to win the lottery: buy a ticket, plug the number into a computer that compares the winning number when it comes out, hook that up so it sets off a very powerful bomb if the numbers do not match, and then stand next to it during the drawing. From your point of view the bomb would never go off and you would win the lottery! or the bomb malfunctions somehow... but from our point of view you almost certainly die spectacularly. I'd prove it (to myself) by trying myself, but unfortunately I live in the universe where me not doing it was a far more likely way of continuing to observe the universe. :(

[Dankdalorde]

I hope my dad is happy and living out there in a different timeline-in fact I hope that everyone who has and will ever have lived is out there in eternal happiness. RIP to everyone.

[Valdagast]

This is why I don't let physicists near my cats.

[daggerdan]

Does that mean there is a timeline where every single particle in the double slit experiment happens to land in the spot predicted by scientists, stopping them from ever discovering the wave function?

[samg]

You explain rather complex stuff in a brilliant way. Well done.

[ericpowell]

"Choose your own adventure, and steer this version of you towards one of the more awesome many world branches of space time"

[edit]

building an entirely new house to escape washing the dishes LOL.

[rajdeeppatel]

you might not realized that this channel will be one of those few reasons which led any future Einstein to continue studying physics..

[Aweshniap]

Shout out to the version of me that's a millionaire

[thiesenf]

Sir Isaac Newtron: For every action there is an equal and opposite reaction.

Quantum Mechanics: For every action there is an infinite number of reactions.

It's kind of terrifying to know that there is an entire universe filled with nothing but my dopplegangers...

[douglasmcneil]

So, he wrote the paper and then "disappeared into military research". Hmmmm.

[mattscatterty]

Regarding the issue of the lack of free will in the many worlds interpretation, I would argue that even in a purely random universe, one could argue that there is still no free will. Look at it this way: pure determinism offers us no choice/freedom. We are enslaved to the pre-determined physics of our particular timeline/world. But with pure randomness, we are still without free will as we are enslaved to the pure randomness of the physics of our universe. We would never argue that a game of Russian Roulette offers us the free will to choose the outcome, so why would physics be any different. If it's just the randomness of quantum mechanics that determines my "choices", how is that different from my choices being determined by the rolling of dice? Does anyone have an idea of a third option that could involve free will?

[MaxArceus]

I build houses all the time to avoid doing the dishes :o

[MrPINKFLYD]

GOD I LOVE THIS SUBJECT. I'VE SPENT 40 YEARS, LOOKING INTO IT AND IT NEVER GETS BORING AND ITS IMPLICATIONS FOR REALITY IS THAT I'M FASCINATED BY

[agustinvenegas]

"building a new house to avoid doing the dishes"

Yeah, that sounds like something I would do

[deepampurkayastha]

DR. Strange must have watched this video before calculating the 14 million outcomes

[cclifford]

I know this was a physics video, but I saw a lot of good chemistry at the end.

[TimothyBrake]

It comforts me to realize that when I buy a lottery ticket, one of me actually wins it and can do what he wants like study this in more detail 😀