General Relativity & Curved Spacetime Explained! | Space Time | PBS Digital Studios

The Final Installment of our General Relativity Series!!!

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We've been through the first few episodes of our crash course on general relativity, and came out alive! But it's officially "time" for CURVED spacetime. Join Gabe on this week’s episode of PBS Space Time as he discusses Newton and Einstein's dispute over inertial frames of reference. Is Einstein's theory inconsistent? Is gravity even a force??? Check out the episode to find out!

Previous Installments of the General Relativity Series:

"Are Space And Time An Illusion?":

"Is Gravity An Illusion?"

"Can A Circle Be A Straight Line?"

"Can You Trust Your Eyes In Spacetime?":

Let us know what topics you want to learn more about:

[MobiusCoin]

Ahh fuck, this is the one channel I'm subscribed to that actually makes me feel like I'm back in high school and I haven't been keeping up with the reading material. Even more than Numberphile and Veritasium, I saw this video in my subscription feed and thought "shit, I didn't fully grasp the final concept of the previous video and this one is out already?" You know when you go into a test knowing you are unprepared? Yeah, that feeling...

[gasdive]

Living proof that it's possible to provide an explanation of something that's *both* simple *and* correct. So many channels get stuff wrong and then the lame excuse is "well we know the real answer but it's too complex for your feeble brain and limited attention span (and this is only Youtube not college)". BULL SHIT. They're just lazy. This video was clearly very tightly worded and shot. The graphics were clear and the metaphors spare and not misleading. I can see the work that went into it and I can't tell you how impressed I am. I wish there was some way to like more than once.

BRAVO, well done! I'm sure I'll be linking to this video in during future discussions on popular science presentations.

[brainfragrances]

I'm not fat, my belly is just a geodesic line in a curved spacetime world

[EhPlusSimRacing]

I just binge watched 6 episodes of Space Time, my brain hurts.

[WaiGee_]

never ever have i been so confused in my life

[Douken]

Don't ever dumb down these videos. They promote that I use my brain and do research which is EXCELLENT

[jehnabaylon]

"This is a bit oversimplified..."
Uh...

[kcwidman]

Phew, I did it. I still feel like I have so much to learn. Every time I hear people talk about this stuff it seems like it's all so clear in their head. I understand that probably isn't the actual case, but it's a lot better of an understanding than what it is in my 17 year old mind. I cannot wait until I can become older, go to college, and learn about these things for no reason other than to satisfy my inquisitive mind. This stuff is so incredibly fascinating to me, and I want to be able to fully comprehend everything that is humanly comprehensible about this very in depth topic. Can't wait!

[shloktrivedi]

Slow down. Make it a 30min video if thats what it takes.

[thecodgamer]

Am I the only one that totally didn't understand this?

[hedderbunderna]

I almost cried. This conclusion made everything ever make sense. Thank you

[jonneysk]

every time he said "in other words" im like "cool im about to understand what this guy is talking about" theeen out comes other words and i still don't get it

[tmanmatt]

I've watched the whole series like 10 times, and I still don't understand how it's the Earth accelerating into the object. Can someone explain this to me?

[momusu]

I find this so amazing that i wish i had payed more attention in school instead of trying to understand it now when i'm 20 years out of school. Even though i don't understand everything i feel like i've learned so much from these videos.

[kbt]

MIND BLOWN!! I recently stumbled onto this channel a few weeks ago, and I'm hooked. You guys have done such a great job at explaining a complex subject matter and explaining it in a way that can be visualized. It definitely takes a few times to let it sink in, but I've read books and gone to numerous other sources to try and understand these principles better, without getting too much into the math—just to try and understand the basics better—and I'm convinced there is nothing I've found out there that explains it as well as this show. Watching this playlist makes me feel like a little kid again, helping me to see how Santa—'gravity'—isn't what I thought it was made out to be. Keep up the great work.

[philipstuckey]

We should replace "gravity" with "co4st" pronounced (coast) for "Curvature Of 4d Space-Time" or something

BTW, is the ant idea analogy for using a differential?

[jesscool]

GABE!! I GOT IT! I mean, seriously! I tried understanding why gravity is shown as a manifestation of spacetime in many videos before but never understood it(or never was satisfied). Its not that I'm dumb but at almost the end of the video, something inside me struck and everything became clear!! OMG!! I think I have a better way of visualization. Just take a piece of flat paper and draw any straight(to avoid confusion) line on it and a random point. Now, curve the paper about that point. The line, as seen from outside appears bent. If that line is extended along with the paper indefinitely, you could see a path which resembles objects under "gravity". Not just that, if you mark points on the line at regular intervals of time while drawing the line at constant speed, and then curve the paper as we did earlier, you can totally visualize gravitational time dilation as well.

[buddhapunch]

Man, I always thought I was pretty sharp until I started watching these. I can understand some of the pepperoni and mushrooms, but the pizza escapes me. I guess that's OK for having zero formal education in physics though.

[nichas]

Just found this series and watched it all twice. I think i somewhat get it and it was truly enjoyable. Eyeopening stuff. Thank you guys so much for doing this.

[ScienceAsylum]

Amazing as usual. Relativity is kinda my thing and you do a very good job with it. A couple (slightly off topic) questions though:

1) I always read that when you use quantum mechanics and general relativity together, you get unrealistic results like zero or infinity. However, I've never seen any of the math that shows this. I used them together in my masters thesis (about white dwarf stars) many years ago without much trouble. Do you know of any sources that run into this problem?

2) How did you get linked up with PBS before you even started making videos?