Quantum Gravity and the Hardest Problem in Physics | Space Time

Between them, general relativity and quantum mechanics seem to describe all of observable reality.

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Luke Maroldi
Assistant Editing and Sound Design by Mike Petrow

The first few decades of the 20th century was a time of miracles for physics. First, Einstein’s relativity utterly changed the way we think about space, time, motion and gravity. Then the quantum revolution of the 20s and 30s overturned all of our intuitions about the subatomic world. Together, general relativity and quantum mechanics have allowed us to explain nearly every fundamental phenomenon observed, and have predicted many unexpected phenomena that have since been verified. And yet the two theories contradict each other in fundamental ways. In the century since that golden era of physics, we’ve been trying to reconcile the two … without success. But today on space-time I’m going to begin our discussion of the great quest for this union – the quest for a theory of quantum gravity, and for a theory of everything.

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سلطان الخليفي

[freddanfly]

Police man : You were speeding, do you know how fast you were driving?
Heisenberg: No but I know exactly where I am
Police man: You were driving 100mph
Heisenberg: Great, now I am lost.

[PlebstersPictionary]

You know an equation is hard when it includes pitchforks and sweating letters

[anushkagupta]

Beginning: cool i understand
Middle: hold on-
End: what is an e l e c t r o n?

[gacha]

"The non-renormalizability of quantized general relativity is connected to the idea that precisely localised particles produce black holes."
That's a great pickup line

[cineblazer]

I can't even put into words how high quality this content is. Or how amazed I am that I'm learning it for free. You guys are absolutely incredible.

[ernestolombardo]

Well that was bloody spectacular. As a layman who has been avidly reading content on the subject for almost four decades, this is the first time I have ever caught a true, clear glimpse of some of the finer details in the incompatibility problem between General Relativity and Quantum Mechanics, and this is making me feel all warm and fuzzy inside, like I have just gained a bit of super cool insight.
Thank you.

[ptimal]

This guy is a terrific host. He explains/behaves in a way that keeps you interested and understanding. Charisma. Lots of other people would be robotic and boring reading the script.

[TheTMFD]

Every other sentence has me daydreaming about something new. Very thought provoking and I end up missing something else. I gotta keep rewinding to catch what I miss. So much information at a high speed. Fantastic!

[sebastianelytron]

The hardest problem in physics is why gravity acts 10x stronger when your alarm goes off at 7am🤔

[dann]

Don’t take this the wrong way but these are really the best videos on youtube to fall asleep too. Matt has such a nice and easy way of talking that it’s really calming. Thanks for the many well rested nights.

[benkao]

It is so fascinating that, with measurement and mathematical logic, humans are able to access the nature of our universe.

[atlas]

"How much information does the universe contain?" I'm still trying to figure out how much information this video contains. I'm sure both figures are far beyond my standard measurements.

[lorenzodaidone]

This channel has taught and motivated me more than my 12 yrs of school. I appreciate it a lot.

[maccharcosplaycatalogueceo]

I love this. It isn't just rehashing general relativity, but going on the edge of the mysteries. The way you explain it doesn't assume no one watching is a scientist!

[Tricosis.]

mmhmm ... ... yeah ... mhmm ... I know some of these words.

[MasterDJRenn]

I understood about a planck length worth of this stuff.

[SahilAsterix]

Y'all sleeping on the fact that this man spoke for 16 continuous minutes about quantum mechanics and general relativity without stuttering.

[AZZKlKR]

10:22 "Brought back to reality, " oh there goes gravity.

[lllll]

6:28 finally i understand the planck length

[papaclanc]

My parents told me if I studied perturbation I'd go blind.