Quantum Gravity and the Hardest Problem in Physics | Space Time

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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
Made by Kornhaber Brown (www.kornhaberbrown.com)

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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Keith Marcus says:

And I thought Vsauce and Veritasium were hard…

awsomeabacus says:

I have two physics degrees and I barely understand this.

Jon Bain says:

There are simpler ways of explaining the quantum-relativity catastrophe. Quantum time implicitly states that the smallest unit of time is a quantum of time. So how can relativity claim that this time unit can be altered? Also black-hole theory states that nothing moving at lightspeed escapes past the event horizon and yet it also implies gravity moving at lightspeed getting past the event horizon. 😕

Jaigeeshavya Kanuparthy says:

I know the universe is expanding and all that is present in universe has certain velocity… Is there anything in the universe which is always at state of rest with respect to a coordinate system outside universe.. if it exists what are it's quantum properties?

David Murphy says:

I'm too sober for this shit

Never Again says:

i cant go without cringing when some one mentions the Theory of everything.
Makes all scientists sound like noobs.

like "Dude we found God!"

Richard K DeLancey says:

Albert Einstein, The grand aim of all science is to cover the greatest number of empirical facts by logical deduction from the smallest number of hypotheses or axioms. Richard DeLancey

Richard K DeLancey says:

Max Planck's, A new scientific truth does not triumph by convincing it's opponents and making them see the light , but rather because …A new generation grows up that is familiar with it.

Richard K DeLancey says:

The answer your looking for is with Max Planck's Quantum Tunneling and Murray Gell Man's work! Richard DeLancey!

Danger Close says:

Fall into a black hole and just look behind you. You will see the universe move in fast motion, millions of years for each second you experience.

Danger Close says:

Einstein could never show what we all learn…..that time passes faster the older we get!

FalcoGer says:

We have measured time dilation due to velocity and lower gravity in orbit. have we similarly concrete evidence for quantum mechanics that can't be explained another way?
Certainly if the two conflict one of them is not right.

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