Where Are The Worlds In Many Worlds?

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Many Worlds interpretation of quantum mechanics proposes that every time a quantum event gets decided, the universe splits so that every possible outcome really does occur. But where exactly are those worlds, and can we ever see them?

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria
GFX Visualizations: Katherine Kornei
Directed by Andrew Kornhaber
Assistant Producer: Setare Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber

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[stevenmellemans]

Stop performing these double slit experiments. We’re running out of space to store these universes.

[Jassbusters]

Damn, I ended up in the universe where this doesn’t make any sense

[matthewtopping]

How much of the viewership of this channel have absolutely no idea what he's talking about every time, but just listen anyway? Just curious.

[videosbymathew]

"At the risk of getting technical..." that's a big point of this channel! Don't hold back! :)

[colonelwest]

“Ahh yes, quantum” I nod at the screen like I actually understand any of this while stuffing Doritos into my mouth.

[SpydersByte]

definitely looking forward to the video on how we could communicate with the other worlds, that sounds interesting.

[harmonicpsyche]

"At the risk of getting too technical, "
-Dr. Matt O'Dowd, summarizing PBS Space Time

(edit: to clarify i still love pbs space time in all its technical jargony goodness)

[debrachambers]

It's interesting to me to imagine a universe where every double slit experiment gives results that don't show a wave nature of particles because of dumb luck, so scientists have a worse understanding of quantum mechanics.

[vampyricon]

Speaking of "splitting quantum spacetime", there is an interesting consequence of this:

We know there is no general way to say which two points are "the same event" in two different spacetime manifolds, and since this measurement would cause you to do something differently, that means the spacetime would warp differently in the two different branches as well. Which means the spacetime manifolds would have to be in superposition as well as decohered, and you can't really match up where you are in this branch with a location in the other precisely.

[Petergoforth]

In my other position wave function and phase relation measurement, I actually understand this.

[cherubinth]

Please, more about the recombining of wave functions?

[ardan]

This hits different after that Loki ending

[MichalGlowacz]

Wow, that was a great explanation! A pond analogy somehow feels much better to me than a branching tree. I'm not sure if I'm a fan of the many worlds interpretation, but I think after watching this video I understand it better (obviously on my very shallow, amateur level). Thank you!

[JoeBigBoi]

I just hope my other variants understand this episode better.

[thechickenduck]

I love that many topics like the double slit experiment are briefly explained again, to build refreshers for non-physicists like me. This helps me still get the most out of the video- thank you for the great content

[DanielZat]

I actually thought the whole universe splits at every wiggle. Recombination makes this far more confusing and even more interesting. It also makes me wonder if there could be something like a partial, local, or pocket-like split, where a split is still attached to or recombines with its origin.

[ExcretumTaurum]

Tbh I can’t really imagine there being any world where I would pick salad over pizza.

[NeutrinoParty]

"the entire world doesn't split with every atomic wiggle", only due to interactions.
Q: does wiggle refer to virtual particles popping in and out of existence? What is the shortest distance (volume) that could include an interaction?

[VoightComp]

My brain has just split into two migraines. This is heady stuff

[alexandermartin]

Great video. PBS Space Time, Isaac Arthur, John Godier, and The Exoplanets Channel are definitely my favourite channels!!