The Best Test of General Relativity Brian Greene Explains That 1 day ago   11:52

A launch mishap led to the best experimental confirmation of gravitational redshift. Get a free audiobook with a 30-day trial of Audible: or text VERITASIUM to 500500

Huge thanks to
Dr. Pacome Delva:
Dr. Sven Herrmann:
Gravitational Redshift Test Using Eccentric Galileo Satellites:

Disclaimer: It is arguable what is THE best test of general relativity because there are different ways to test the theory. This is the best confirmation of gravitational redshift, which is one of the three original tests proposed by Einstein.

Special thanks to Patreon supporters:
Donal Botkin, James M Nicholson, Michael Krugman, Nathan Hansen, Ron Neal, Stan Presolski, Terrance Shepherd

Animations and editing by Alan Chamberlain

Music from "Subtle Substitutes 2" "A sound Foundation 1" "Cell Research 1" "Particle Attraction 1"

Comments 1617 Comments

I’d be interested to know your thoughts on this format. Would you like to see more ‘Talking to scientists about their recent publications on Skype’? Maybe not on this channel but on Sciencium perhaps?
I dont´t understand. He says that they achived the goal but they say they didn´t. It´s confusing.
To illustrate how strong gravity is no matter the distance. I have a short mind game for ya'll. Lets say there is nothing else in the universe than you and a pack of cigarettes. If we were to place the pack of cigarette as far out away as the known universe horizon. The gravity will pull you closer to that pack no matter the distance if there is just you and a pack of cigarettes existing in the universe. So what is reaching out that far in an instant like that?
Hi, thank you for a great video. Just wondering, was it really the photons, or could it be the solar wind with some electrons and protons that affect the trajectory? thanks
Hardik Susara
Dear friend I dose not understand that
A maser clock Is not an atomic clock.
Sanny Devito Oof
I like to watch this while playing Minecraft
Conor Orion
when you say ''clocks tick slower in stronger gravity'' do you mean time itself or just clocks. i.e. would a digital clock run slower in stronger gravity
Fake it til you make it and trust in the ignorance of your audience.👍
Filip Penzar
@Veritasium; Could you actually fall into a black hole, or would the black hole 'die' before that happens?

So according to general relativity, time 'slows down' in areas with a big gravitational pull (such as black holes).
According to Hawking, black holes lose energy (thus mass) in the form of Hawking radiation but that proces is very slow, 10^70 years lets say (from our perspective).
But since time slows down the closer you are to the center of a black hole, time needed for a blavk hole to 'die' would greatly decrease.
My question is, by the time you get to the point of 'no return' or 'spaghettification' of the original black hole you were falling into, wouldn't that border move further towards the center of the black hole (from Hawking radiation), thus not killing you, and wouldn't this proces continue until the black hole evaporates, making you never able to fall passed a certain point?

Does anyone know anything about this? All the articles about 'falling into a black hole' just say that after you've passed event horizon nothing can escape... I would love to get an answer to this question.
Abishai Paul
And then the ghost of Einstein helped to prove his own theory. THE END.
Compte Random
I love the french accent of one of the guys
k and what if u are on a centrifuge? i mean it feels like increased gravity, so shouldnt that affect you aswell? if no then that would mean acceleration-force wouldn't affect time dilation which it allegedly does. so how does it work in a centrifuge? someone explain pls ty
Marco Maiocchi
He just showed a huge villa with pool and he still wants more money?^^
Annant Sharma
According to general theory of relativity, a body with mass stretches the space and thus making a wave to travel more on earth than a wave traveling in a space far away (time shift). If that is true, could we go far enough from celestial body that a wave travels no distance and time stops ultimately.
j. rodman
Seems weird not to mention Gravity Probe B in this video.
unknown mindyourown
Still beating on the dark matter and dark energy theory? Give it up you’ll never find it
It also kind of looks like the doppler effect
The trilogel !
So if I put two fly's on two different satellites both orbiting Earth, one much further out than the other, knowing that both fly's would normally live approximately one week (on the Earth's surface) would I expect the fly on the furthest orbit to die before the other one? If so, does that prove that time is not a human construct but is in fact a property of reality?
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Brian Greene Explains That The Best Test of General Relativity 1 day ago   07:55

Theoretical Physicist Brian Greene explains how the universe works using a water bottle and disco music.