Can Space Be Infinitely Divided?

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How many times can I half the distance between my hands? Assume perfect coordination and the ability to localize my palms to the quantum level. 15 halvings gets them to within a cell’s width. 33 to within a single atom, 50 and they’re a proton’s width apart. Half the distance 115 times and they’re a single Planck-length apart - 1.6x10^-35 meters. Surely we can keep going - .8, .4, .2 x10^-35 m? Bizarrely, those distances might not even exist in any meaningful way.

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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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[gabrielpetre]

It was proven some time ago that the X to close an ad is indeed smaller than the planck scale

[edwardstiffler]

I'm continually disappointed that the Planck Length is never represented with a tiny wooden plank.

[TheRealBoof]

I'm an astrophysics PhD student and this YouTube channel teaches me new things. What an extraordinary time to be alive, when these kinds of resources are readily available and presented in such an engaging way!

[falco]

Physics: How small can we get?
Heisenberg: Maybe.

[TKSSLCHN]

Physicists in the 19th century: "It's basically solved, we already know everything"

Physicists in the 20th and 21st century: WE DONT EVEN KNOW WHERE THINGS ARE

[RR-qpkp]

Your contribution to communicating physics to the public is brilliant - always concise, but pitched at an intelligent level and understandable. I’m very grateful for what you do and thankful that you’ve been doing it for this long. Just wanted to say thanks to Matt and the team

[radishpineapple]

4:03 I burst out laughing at this animation, I couldn't help it. Video editor, whoever you are: you need a raise.

[klauskervin]

This is the best explanation of the Planck length I've ever heard. Bravo and thank you PBS!

[keonix]

10:22 "distances are *undefined* "

We are all doomed, universe is written in C++

[TKSSLCHN]

"You'll have to stay tuned to the future of physics" well damn that's a cliffhanger if I've ever seen one

[nopeno]

Planckstronaut 1: "Wait, it's all undefined?"
Planckstronaut 2: "Always has been."

[BrokenSymetry]

The amount of work this channel has done promoting science on this platform is just amazing

[ativjoshi]

This is the most intuitive explanation of plank length I've seen so far.

[crystaldazz]

"You may see where we're going with this"
Me: You vasssstly overestimate my brainpower.

[sionnach]

I've often heard this heisenberg principle mentioned
I'm just not certain about it

[XKloosyvv]

I'm loving this channel. Halving numbers to infinity is always a concept that fascinated me as a child. However, learning about Planck values has completely shifted my way of thinking about an infinite universe.

[dembro]

The Tortoise sure hopes space is infinitely divisible so Achilles can't ever catch up to him.

[djbslectures]

Space time tag line: "We need a theory of quantum gravity to answer that"

[davroscaan]

So, I'm going out on a limb here and guessing that shouting "I'm hung like a plank!" will get a different response at a party full of sawmill operators than one with physicists.

[Gnurklesquimp]

I remember this idea was very surprising to me when I first heard it, large and small scales have always been some of the most interesting concepts to me, easily in my top 10 of areas where I'd love to see major breakthroughs.