The Maths of General Relativity (2/8) - Spacetime velocity

In this series, we build together the theory of general relativity. This second video focuses on the notions of velocity, vector components, and we write down our very first equation.

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Alessandro Roussel,

[Pidrittel]

“The maths of General Relativity” or “How Physics actually should be taught”. Simply brilliant.

[fyu]

This channel might probably my greatest Discovery since 3Blue1Brown. Just wanted to say I am absolutely astounded by your content!

[Pidrittel]

How good can the visualization get?

Alessandro Roussel: “Relatively good.” (pun intended)

[elpak]

I project that, by the time you are finished, this will be the best explanation of general relativity available in the entire world for a low-level audience. Congratulations, it is looking fantastic. I am a Senior Lecturer at King's College London Physics Department, and look forward to the rest of this series.

[ClemensAlive]

Policeman: "You know you were speeding, right?"
Me: "No. I just had a different vector through space time."

[onicalcron]

I am excited so much I want to go orbit a black hole so I can come back with all videos uploaded

[particularminer]

1:11 “More generally, all objects in the universe move with exactly the same speed ... the speed of light”
Perhaps this statement is intended to grab the attention of the listener.
But while that’s true in the context of spacetime, our everyday use of the term “speed” is quite different.
“Spacetime speed” is probably a better moniker.

[jiriverkijk]

Ngl I’m pretty excited, 10/10 best channel for relativity out there!

[archishmannag]

These 6 minutes feel like 6 days before premiere!

From Einstein's theory of relativity!

[Sasukej]

This channel slowly gaining popularity is the best thing ever!

[PoseidonWasTaken]

I like that these videos are so short. The math is kinda hard to fully wrap your head around and these small segments gives me time to absorb the info between videos

[imagine.o.universo]

Hello I am a bachelor and this was the first time I formally study general relativity. I can say that your work helped me a lot! It was brilliant! I believe this is the best material on the internet to explore the concepts behind this subject.

[nero]

I really hope this channel gets the recognition it deserves

[LagAttacktoSlay]

I really can't wait for someone to comment about their moment when it all clicked. It's really a joy seeing someone enjoy such topics, and you make it easier for us!

[enotdetcelfer]

Between this channel for relativity, and Atoms and Sporks for quantum mechanics, I'm loving all the "let's get a better intuition" stuff recently. I wish I had learned this in school first... it's sad we're still taught the old stuff first and then have to unlearn it in a sense. Can't wait for more vids to get translated!

[mikemironov]

I just want to appreciate the production quality of animation!
Whoever done this - great job!

[Alex-bwyd]

This series is god damn good. Literally the best way to understand Relativity. I had a pretty good grasp before but it was difficult, but the first video (and I'm sure the subsequent videos) was so good at breaking it down and really explaining how truly bizzare and amazing Relativity actually is.

[anywallsocket]

These explanations are not only logically and visually very palatable, they are like music for the coherence of my soul <3

[NeedsEvidence]

1:45 Small technicality: If you measure time in *seconds*, and distances in *light seconds*, then the speed of light is not 1 but 1 *light second per second* (a *light second* is NOT a *second* ). You could, however, define the unit of distance as *1 second* (the _time_ representing the _distance_ light travels in 1 second). In this case, the speed of light is 1.

[ayushmaanyadav]

Thank you so much for doing this series in english. You guys have the best animation! Please do other topics too. Like coriolis force.