PBS Space Time - 2015-07-02
Want to ask some sort of crazy question about Space?: Tweet at us! @pbsspacetime Facebook: facebook.com/pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: http://www.reddit.com/r/pbsspacetime Support us on Patreon! http://www.patreon.com/pbsspacetime Help translate our videos! http://www.youtube.com/timedtext_cs_panel?tab=2&c=UC7_gcs09iThXybpVgjHZ_7g Let us know what topics you want to learn more about: http://bit.ly/spacetimepoll General Relativity! Spacetime! And... Curved Lines? On this week's episode of Spacetime, Gabe talks about what it actually means for a line to be straight so we can better understand what we mean by the idea of "curved Spacetime". This is Part One of our series on General relativity, so be sure to check it out! Links to Annotated Previous PBS Space Time Episodes: "Is Gravity an Illusion?" https://www.youtube.com/watch?v=NblR01hHK6U "Are Space and Time an Illusion?" https://www.youtube.com/watch?v=YycAzdtUIko Extra Credit: Visualizing parallel transport and geodesics on a sphere: http://www.applet-magic.com/paralleltransport.htm http://www.smith.edu/physics/felder/curvedland/tutlines.html More mathematical PDF about parallel transport and curvature: http://www.physics.ucc.ie/apeer/PY4112/Curvature.pdf ----------------------------------------------------------------------- Comments: Jordan Filipovski https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z125y1czyym1i12q204ccvn4fzvqhjg5uus0k MaybeFactor https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z13wyrlqivrwu34is04civgpczbztvcqg40 scharfy https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z13wtrl4xojqhx4pw04cfnig3tantf4hjdc ourpensareourlips https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z125it5y0mnetfcmo22ssvxamvelud4i004 JakeFace0 https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z12dhvjqmtqltxidj22zjlq5fsumsbib304 QuannanHade https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z12iildz2pacjfms122lspjglnudh1idf Ali Muzaffar https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z13ccvo5kw3cftgkf23htf45bxqiwxvph04 Marko Nara https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z133zfmhzyzezbxm523ayp2pxq35fbjbj04 Indigo https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z13pcbqphnvvtnspe04cdp4hstflxnwh5as Jose Catlett https://www.youtube.com/watch?v=bT3hBK6kAJQ&lc=z13wgfewdtmutxmrf04cj1aqhtzsft4h31g Music: u dont know im fadin Secret Society - Logical Disorder (http://logicaldisorder.bandcamp.com/) Movement 3 - Janne Hanhisuanto (https://soundcloud.com/jannehanhisuanto) Philly D Jr - Patternbased (https://soundcloud.com/patternbased) Earth Breath - Human Terminal (http://freemusicarchive.org/music/Hum...) Deep Blue - Janne Hanhisuanto (https://soundcloud.com/jannehanhisuanto) Saw Slicing - Patternbased (https://soundcloud.com/patternbased) Heisse Luft - Thompson and Kuhl (https://soundcloud.com/phlow/05-x-com) miracle - slow (http://www.restingbell.net/releases/r) Tropico de Tauro - Sr. Aye https://soundcloud.com/sr-aye) New SpaceTime episodes every Wednesday! Hosted by Gabe Perez-Giz Made by Kornhaber Brown (www.kornhaberbrown.com)
Very good video. Most discussions of this topic either lose their audience by going into tensor equations, or are completely oversimplified to the point of completely losing the essence of the topic. This video strikes a good balance between the two extremes.
PBS spacetime is a channel for those that know about the stuff since a while, and want a little more challenge, anyway most equation are just a way to explain things visually instead of verbally, i think that physic and philosophy are often intertwined
Omg !!!!!!! Funny seeing u here !!!!!
This may be the first time I've subbed someone without seeing a single video, per the respect shown here.
k
@PBS Space Time I have a question about the geometric shape of the universe
Like the flat universe or the closed universe and the open universe like a horse saddle
The question is, does the geometric shape of the universe explain the origin of the universe before the Big Bang?
Please send this question to cosmologists
I'm apparently as dumb as an ant!
You aren't its just that geeks like to explain things in a way overcomplicated way! Like if you got the job description for an administration clerk and didn't see the job title youbwould be like whaaaaat! But you actually do the job and realise how easy it is! Same shit basically!
but apparently you're NOT an ant! :-)
You and me both Bro!
i hate these kind of comments, you don't understand not because you're dumb it's just that you need more practice in the math behind it which is abstract but not hard, and general interest in the subject and it's details
@3li or as smart 😁
I am having flashbacks to the differential topology classes I took in grad school. It kind of hurts, but only locally.
+n124lp haha :D
What he's saying here, if I understand correctly, is that, in a manifold (I hope I'm using that correctly) you take the local Euclidean approximation, and use it's definitions of parallelism and stuff to parallel transport vectors. Please correct me if I'm wrong
@n124lp lol "but only locally" ahhahaha
🤣🤣
I love how Einstein said "F-you" to all our beliefs about physics
And got it right.
"To all our beliefs" you mean to all newtonian beliefs, because obviously we live in a post-einstein world
For every point of view there is at least one fan at YouTube. That's why all these reactions are useless. People only want confirmation. Poor things.
Thank you.
Request: please, slow down at important parts to give viewers few second to digest idea. Thanks!
Settings Playback Speed .75 or less. :)
This is the first time a Youtube educational video has ever truly stumped me. Wow.
@Rockerchavnerdemo there is a lot of good channels education wise out there on the big interwebs. numberphile is quite interesting, but not so much of educational
@Munchausenification It's onyl educational if already understand how crazy math and numbers are
@Munchausenification I think numberphile does a good job in raising peoples curiosity about math. After school, people usually don't want anything to do with math as it's explained horribly there. I think numberphile made a lot of people think "that's interesting, I wanna know more", which is great when it comes to maths.
Yes, the things they bring up is not something you might be able to use in your everyday life for example Zeno's paradox is more of a philosophical question than actual learning about math. If Rockerchavnerdemo is reading this comment section still then i would suggest the site TED. interesting, fun and educational.
There's just a lot of words to know to understand it quickly
6:52 "Connectedness and Topology are global. Curvature and Geometry are local." In one sentence, I suddenly understand topology. WHY DOESN'T ANYONE EVER SAY THAT?!?! Thank you so much for simplifying (but not oversimplifying) difficult topics.
I try to do this on my channel a lot, but sometimes I fail because I only give myself about 4 minutes. Sometimes you just need more time and you do a good job with it in 10-12 minutes.
@bossoholic I agree, that "ridiculous comedy" is actually fun
@Graig Simmonette -- The topological equivalence of a doughnut and a coffee cup is not discussed in a first semester course on point set topology. It's discussed in algebraic topology when discussing homotopy theory.
I still don't get it lol. my brain cannot find logical connections from these words.
@PBS Space Time I have a question about the geometric shape of the universe
Like the flat universe or the closed universe and the open universe like a horse saddle
The question is, does the geometric shape of the universe explain the origin of the universe before the Big Bang?
Please send this question to cosmologists
A topology and geometry lecture playlist https://www.youtube.com/playlist?list=PLTBqohhFNBE_09L0i-lf3fYXF5woAbrzJ
0:27 everyone knows that the coolest person in the party talk about physics
it's hard to follow your speaking to get a good understanding of this video
Yeah he v is speaking extremely fast
Under 301 club!
+John Bell Right. The problem is the intuition, which we have built up working with vectors and directions in general in flat spaces, mainly the plane. Like so many concepts in science and mathematics, when you generalize them beyond the environment in which we have developed our intuition, the intuition breaks, and we have to learn new strategies for thinking of things under the newly defined conditions.
ElectroBlood
PBS Space Yu
PBS Space Time do circles excist
This is a better explanation of parallel transport ----> https://youtu.be/jNQCOknMZKg
"Otherwise what I'm about to say will make no sense" funny.
its not the spoon that bends...
Literally lold at dat; have a like
+C Martinez lol sorry, but you aren't "the one"
its your mind that bends
OMG I GET IT NOW *brain explodes
but... there is no spoon...
"Read gravitation book" -> googles read gravitation online -> Ohno.jpg
These are EXCELLENT videos! Often this stuff is "dumbed" so much that all the videos dealing with this topic are essentially the same and really teach nothing....or at least nothing new. I find your approach to be much more robust while taking into account that many people who come here probably have an interest in this subject to begin with.
I really understand nothing unless I can visualize it and those who claim to understand pure mathematics......well good for them, but I do not. I think these are things that will draw more and more interest over time. The internet culture is in its infancy and as time passes I am sure parents who have learned new things online will pass this along to their children. Clear, intelligent and concise descriptions in physics or any topic for that matter are very important to society as a whole. There is a reason people still enjoy lectures by Feynman and others. Too often is it the case that things are basically "dumbed" down because people who work in media fear their audiences are too stupid to understand these things. Everything is based upon selling to the widest swath possible. The problem more often is in the way things are presented rather than the material itself.
@Mark G That should be - "dumbed" down - in the second sentence. I erased the word on accident.
@Mark G Right on. Gabe really manages to visualize these concepts, without over-simplifying it. I'm currently an engineering student, but I'll most likely never touch on these specific subjects, so it's nice to just learn abut them, without meddling too much with the actual physics.
you can only say that if you're already familiar with the topic to some depth, this video is really not meant to convey these ideas to the "large audience", this is meant for people with background in the topic of differential geometry.
If you listen carefully, you can hear his mouth sticking together making a moist sound.
Lol
Beautiful observed sir. Well done, well done.
For the record, this topic has a tendency to confuse the brightest of people. Don't be surprised if you get a little lost. I personally have self-studied everything from string theory to quantum physics, and back when I was on this topic was when I got stuck the most, it's just hard to grasp.
If grasping this topic is hard enough think about how hard coming up with this would be, einstein was truly a genius
0:16 You would not sound cool at all if you said that at a party.
+Archie Dodge Maybe if you were at a college party at MIT lol
Take a shot every time he says "space time". JUST KIDDING. Don't do it. You'll die.
Just ask a line what he thinks about home-decorating to see if it's straight.
+Peter Timowreef Holy crap, I literally laughed out loud on that one.
Boring pun zZZ zZZ
lmfaoooooooo i'm gay and this is funny
@Blueis Notgreen u will be ok.
1:02 Can anyone tell me how to draw that Geodesic? I have to use it on my project.
You're talking way to fast :(
Settings Playback Speed .75 or less. :)
It's not often that an educational program manages to thoroughly challenge my brain without completely alienating me from its content. Programs like these are usually either so over-simplified as to be meaningless, or so esoteric as to be inaccessible to the uninitiated. This video, and this entire channel, hits the bullseye between the two every time. Keep it up!
“Go watch this video now, otherwise what I’m about to say will make no sense.”
It still doesn’t lol
I'd love a series on Maxwell's equations and EM. waves explained so well!
"Anyone can say those words at a party to sound cool."
Those are not the words I use to sound cool.
I love this channel, it tickles my brain in just the right ways :')
"You can slide the tangent along the line, while keeping the tangent parallel to its original direction"
That's fine, but if you can do this, then you already know what a straight line between these two points is. If not, you wouldn't have enough information to know if you were keeping the tangent parallel or not
Isn't a vector a form of straight line? So would that definition be circular in its reasoning? (no pun intended).
Amazing high quality vid about space time :) recommended
I'm really impressed by the quality of these videos. Keep up the great work! I like how these are a bit more technical than the other channels I follow.
I have been watching these episodes for the last two weeks and feel like my head is going to explode
You're missing a ' in "straight."
This is QUALITY content. Hands down, one of the best channels on Youtube.
Love the Star Trek sound effects! :)
You lost me at "Buckle Up" 2:15
I'm so in love with your channel! Keep up the good work!
If the curve is big enough and the viewer is small enough, yes. Hear that, Flerfs?
This is a really great video. Thanks for taking the time to explain it, especially considering how confusing this can be at times :)
You videos really blow my mind but I enjoy watch these as they helped me understand some complex concepts. Thanks again!
Great episode episode on relativity Gabe! Looking forward to the next. 👍
Awesome as always! Best YouTube channel ever!
One question: I was told a long time ago that the shorted distance in a curved space is not the "straight" line (understanding the classic plain definition). Then the shortest distance is the geodesic? Or is it a different one? I mean, these would explain a lot of the weird plains paths!
Thanks a lot!
@jasc14 The shortest distance is the length of the minor arc of a geodesic.
Ha I was thinking about watching multiple times and different videos before he/you even said.
Of course my statement is relative to the person reading it. Had to make a relative statement for a relative video
OMG that guy talks fast.
This video and authour could easily have million views/subscribers if all went in a bit lower tempo
really intriguing question here: if space is stretching (expanding) and accelerating, should we not be able to see F=m.a working at all?
Could you elaborate on what you mean by 'seeing F=m.a working'?
Talk slower Cuz!!!!
Can we just refer to the revent vifeos as the "Is my life a lie?" saga.
good stuff, can't w8 for part 2 and 3 ^^
onlyonewhyphy - 2015-07-02
"Anyone could say those words at a party and sound cool..."
I wish! What party's this?