What If Gravity is NOT Quantum?

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The holy grail of theoretical physics is to come up with a quantum theory of gravity. But after a century of trying we really have no idea how close we are, or it it's even possible. But we shouldn't feel bad because it turns out that the universe is doing everything it its power to make this as difficult as possible. Or it's telling us that it isn't. Should we take the hint?

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Hosted by Matt O'Dowd
Written by Christopher Pollack & Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini & Stephanie Faria
Directed by Andrew Kornhaber
Associate Producer: Bahar Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
Executive in Charge for PBS: Maribel Lopez
Director of Programming for PBS: Gabrielle Ewing
Assistant Director of Programming for PBS: John Campbell

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This program is produced by Kornhaber Brown, which is solely responsible for its content.
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[mkst]

That bit with the equations ending up with the Schwarzschild radius is like the universe is doing stand-up comedy and going “thank you, I’m here all week”

[evolancer]

My favorite channel where I don't understand 90% of what's going on but still continue to watch lol

[JackDespero]

The fact that from quantum definitions, such as the uncertainty principle and Planck's distance, one can derive a relativistic concept such as the Schwarzchild radius, seems to indicate to me that there might be something there that connect both.

[stordarth]

The fact that the graviton detector model maths spat out the Schwarzchild radius and so would prevent any confirmation of the existence of the graviton made me laugh more than it should have. The irony is amazing.

"We did it! We made a graviton detector!"

"Awesome! Where is it?"

"In that Planck-sized black hole in the cor..." <black hole evapourates and explodes>

[ravenragnar]

This is what S tier quality content looks like Youtube. Promote more of THIS and less REACTIONS/PUNDITS/CLIP CHANNELS to the world. Signed the Internet.

[agett]

Us: what's gravity really?
Universe: Shhh don't worry about it

[JosePineda-cyom]

The more i become convinced Emergent Gravity proponents are onto something... gravity doesn't act at all like the other forces, most likely becouse it's not a fundamental force but rather an emergent one, like pressure

[TazTalksYouListen]

11:51 - Thank you for clearing up what a kilohertz was. Everything else in this video is easily understood, but without knowing what this strange kilohertz thing was, none of it would have made any sense whatsoever. So, thank you again.

[Gnomaana]

This always confused me. Doesn’t Einstein’s theory mean that gravity is NOT a force but the curvature of Spacetime? If so, why would it act the same as the other “forces” and have any need to be quantized?

[Nonamelol.]

It’s crazy how literally the most recorded/observed universal force still remains a mystery.

[TharunAshKetchum]

Matt I did the survey, just for you!
To show my gratitude towards you.

So kind of you for posting videos that helps me to increase my knowledge and intelligence time to time!

I eagerly look forward to more videos from
SpaceTime!
❤

[davecool]

The way the slowly zooming stars do a parallax scroll when Matt is moved around the frame is just perfect.

[SuperLoops]

15:05 I literally got chills when that equation appeared. is that as weird/spooky as it feels?

[PlanetXMysteries-pjnm]

"Your videos always leave me in awe and eager to learn more about the mysteries of the universe. Thank you for fueling my curiosity.
"

[gray]

You know one thing that Matt said in an earlier video that I'm going to keep with me for the rest of my life. There really aren't any singularities. A singularity points to a gap in our understanding. Solving the singularity leads to new knowledge.

[tomblaise]

This gives me a good enough reason to live the next few trillion years. Who can be done with life when we still don’t know if gravity is quantized?

[Ruprict]

I always wondered: why would it be quantum if gravity is just curvature of space?

[marius]

If gravitons indeed existed and were emitted by mass, wouldn't that mean that mass would have to be diminishing over time, equivalent to the energy emitted through gravitons?

[themagiccookie]

I love the fact I just begin theorising and mindstroming as soon as we started the questioning!

[chriswhite]

I hope someday all of humanity understands how important these videos are. Incredible work by Matt and the rest of the team; truly a gift to humanity