What If Space is NOT Empty?

PBS Space Time reminds me how much I want to keep learning.

You know you've been watching spacetime for a while when you know who Wheeler, Feynman, Thorne and Everett are and what their contributions were to physics. 6 years ago, I would have had no clue.

PBS is one of the reasons I decided to study physics, currently struggling with classical mechanics, but I won’t give up, the goal is a PhD in physics, thank you for keeping up curious ❤️ Edit: I have passed the module, I’m now doing a physics and pure maths double major for my final year, next update will be graduation. Thank you for all the positive messages.❤️

This show is such a gift. It strikes that perfect balance of technical details and concepts while not totally abandoning those who don't work in the field.

The analogy of foamy spacetime also serves to explain what I mean when I answer with "nothing" to a "what are you thinking about?" question. A bunch of virtual thoughts and anti-thoughts, altering the geometry of my mindspace. The fluctuations are there if you look close enough, but from a broader perspective it looks perfectly level. In other words: no thoughts; head empty

I've known for a while that the Planck length is the shortest meaningful distance, but I never knew why. Finally being able to connect it to other physics concepts is like a lightbulb moment

I want to thank the writers for their efforts in making this an easy listen and Matt for his oratory skills! It's always a pleasure to tune in and learn about this fantastic cosmos we live in. You guys and gals ROCK!!!

Nothing makes me happier than finding a new episode while winding down body before sleep. This channel is pure bliss. Also Matt is a fantastic narrator ❤️

Great content on a very complicated subject. Matt is a fantastic communicator. thank you PBS for supporting and producing this content.

Man, the writing in these videos is INCREDIBLE. The way you explained the heisenberg uncertainty principle in combination with GR in such a easy to understand and logical way for people who dont have university level physics education is mind blowing. There's no where else on youtube where you get such easy to understand but in depth videos on such insanely complex topics :D

the animators are getting better and better, that's a real treat for the viewers. thanks to the team

that ocean surface analogy was fantastically presented.. thank you pbs space-time team ❤

I'm increasingly uncertain about the amount of beer I actually have under an alarmingly large expanse of foam. I guess only time will tell how much empty space I am left with once it settles.

Imagine sailing in a boat of size of a peanut through an ocean with waves higher than a skyscraper for 40 billion years. And then astronomers catch you and say aha, this fella must have been emitted by a helium atom from galaxy GE-5576 around a million years after the Big Bang.

Audio sounds more natural this time. Appreciate whatever the team has done to improve it. Great episode, too!

this show is such a great contribution to science education and humanity, you take us on the ride of modern physics without needing us to do the math I apprentice your choice of words that convey the innate uncertainty of all scientific theories while recognizing all the work that went into our current understandings It's just a perfect channel and I wanted to thank you for your service

5:00 Be mindful that the Heisenberg Microscope makes it easy to confuse the uncertainty principle with the observer effect. One can argue in this vein to show the trade-off in uncertainties, but it makes it easy to mistake any uncertainty for a product of a measurement, rather than an intrinsic property.

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Can you put up a 10 minute repeating video of that quantum foam? It was oddly satisfying and relaxing. Bonus points if the audio is Matt reading his favorite physics paper.

Quantum scientist here, love PBS Space Time, quick correction at 4:50: The Heisenberg uncertainty principle is not equivalent to the classical observer effect, where measuring a particle’s position disturbs its momentum. The quantum uncertainty principle tells us that the more well defined a particle’s position is, the less well-defined its momentum must be, and vice versa. It’s not that we can’t accurately measure both variables at the same time; the particle literally doesn’t have fully defined values for position and momentum at the same time (depending on your interpretation of Quantum Mechanics). This is unfortunately a common misconception, contributing to the general confusion as to how quantum and classical mechanics are different. For a clear explanation (and explicit confirmation that the two effects are not equivalent) I recommend your original video on the Uncertainty Principle!: https://www.youtube.com/watch?v=izqaWyZsEtY