Spacetime Diagrams | Special Relativity Ch. 2
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- Опубліковано 20 вер 2024
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This video is chapter 2 in my series on special relativity, and it covers spacetime diagrams, rotational and translational symmetry of both time and space, how certain transformations preserve distances (measured in terms of a reference like a meter or second), and so on. We'll wait until the next video to talk about Lorentz transformations, relativity of velocity, minkowski diagrams, and the speed of light.
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Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute!
Created by Henry Reich
Fantastic! The animations were really well done and really helped to clarify the content matter. Looking forward to chapter 3.
Hey! My favorite math channel!!
Hi 3blue1brown!
Go viral Ɛ>
3Minute1Physics is real
@@Narutonokia4 lies! Deception!
Guys, I know it's early in the series. But if you're worried about this video not being 1 minute long I think you'll find that you simply aren't moving at the right speed relative to your screen ;)
Exactly. Your velocity should be something around 0.99739c if my calculation is correct.
Unfortunately time doesn't appear to contract in any reference frame.
cant wait to understand this skskks
i am watching it in quantum world so it does not matter
I know it's late, but I am watching it in a parallel dimension where all velocities are negative :D
3b1b really did inspire you, love it.
What did you find similar in them?
@@ShauriePvs 3b1b was the first one to make a series focused on explaining complex topics using geometric intuition. Minutephysic's series is similar to that of 3b1b because they both explain complex topic with geometric intuition. Although they may not have similar graphics or topics.
Why are so many of the comments about how long the video was and so few mentioning how awesome the animations in this video are? Thank you for your outstanding work, Henry.
The channels name
Fourteen MinutePhysics is always Welcome
always ace ii
Time is relative 😎
14 minutes still stays 14 minutes though. No matter how relative
Dries Borstlap actually not, time is relative, so if I was near a super massive star, my 14mins would be slower than yours.
always ace Thats certainly true. But still, your 14 minutes will seem as long to you as my 14 minutes will seem te me. Its only when you compare that you can tell there is a difference. And what I meant with my comment is that the 14 minutes may be different compared to something else, but still are 14 minutes, not more not less, for the person/thing experiencing it,
Dood, Henry, you've *really* stepped up your illustration and animation game since you first started doing these Minute Physics videos. That pseudo-3D orbit worldline animation was stunning.
+
Calyo Delphi also his voice recording quality and editing have really kicked it up a notch recently!
Imagine Henry brainstorming about this video.
"Thanks to brilliant.org, I'm getting better at drawing & animating. I also thought of making a longer video.
Animation… motion…
Video length… duration…
Drawing… graphs…
Let's talk about fucking space-time diagrams"
I would ask what you did to that cat to make it run away from you at 1m/s.
Probably tried to pet it.
Probably tried to teleport it to the moon, or turn it into a black hole
That's what happen when you try feeding your cat to a black hole.
That's actually sort of slow
He was bouncing the cat back and forth on a spring like 2 minutes before it ran away...
"my son is 18."
"really, does he have a driver's license?"
"wait...18-month-olds can drive now?
metre vs feet: the epic battle
i want to like it but it has 115 likes and because of an inside joke, i can't change it.
@@blauwbeer556 what do you mean by inside joke? Also, someone liked it beyond that, so you can like it now.
@@codinghub3759 just by you saying "what do you mean by inside joke" already tells me you are not inside... but fine, will like it now.
5:52 Cat on plane using X-Y Coordinates.
The cat is in in the back of the plane because people might have allergies in the cabin... Otherwise the cat would be with it's family. 😊
who said we could not overcomplicate things! lolol
I've always wondered about Henry's obsession with cats as examples.
How many cats have been lost to abstract space, Henry?
Approximately infinity. Poor schrodinger is searching for his cats
I think physicists and cats are like proton and electron. They attract each other to nullify each other
Schrodingers Cat still alive !!. or You may Kill it .? well its space and time, so correlative representing in mind is good instead of space
I am rewatching this video 10 months later, and I have no idea what my old comment meant. Can anyone explain it to me?
@@codinghub3759 I guess you were high
with physics
Road to hourphysics
This video is INSANELY well made. I feel I am really starting to understand what special relativity is about. Can't wait until the next video!
Guys, just think of this as 14 one-minute videos strung together.
I was expected that gorgeous hardware rig you showed off last time! :-(
Not understanding space-time diagrams, leads most people to not understand relativity and thus they give up. This is one of the easiest explanation I have seen. Amazing work Henry!
_"Say, we have a cat attached to a spring,"_ ...MUHAHAAAH :P
My spider senses tell me there's going to be a viral video on youtube about some russian attaching a cat to a giant spring in the not too distant future...
5:58 should have been
x_new = x*cos(θ) + y*sin(θ)
y_new = y*cos(θ) - x*sin(θ)
But anyway great video ! Waiting for the next chapters
For second, (after I looked up Wikipedia article) I thought Henry got it right, but eventually I realized you are right. You are truly a genius.
I triggered myself glimpsing over this comment and reading should "of". Damn...
Nice eye! It looks like Henry used the general rotation transform in the same reference plane. However, rotating the axes CCW is like rotating the world CW, or by the negative angle, which would naturally flip the sign of the sines.
Yep. Noticed the same mistake. It is even visually seen how x_new have to be greater than x which is not possible with formulas presented in the video.
Greninjash
I stopped and stared at that frame for 10min assuming by default that Henry was right and I was wrong, since I couldn’t find comments mentioning it
Thanks for saving my day
Best notification I’ve gotten all day 🙌🏼 I love these videos so much! 🤓
Me too!!!
I read your username as your comment at first and was like 😶
I just saw your comment on slo mo guys video too :3
Shreyansh Darshan haha we watch all the same stuff!
Science with Katie I didn't get a notification. 😵
As a physics teacher that has to explain special relativity each year to my students, I really look forward to how you are going to this story.
I wonder what my overall feeling in the end will be, I might completely remake the part of my course that on special relativity.
Thanks so much!
The long wait was totally worth it
at 5:57 there is an error in the rotation matrix, the signs should be inverted the minus should be a plus and viceversa. This is because we are not rotating the point itself but the point of view.
Mobiüs pathways
Yeah,noticed it.I couldn't figure how it would work because x' would be smaller than x
You actually could plot a four dimensional scenario onto a three dimensional grid. All you need is a fourth variable. It doesn't have to be a spacial variable. For example using color. Plotting a 3D system through time where blue represents early and red represents late.
EE Ehrenberg you would have to change colour at every point, and measurement of units smaller than 1 unit would be a drag
I was gonna write how in bounded motion (in particular oscillatory in a circle) it would not be possible to determine the angular velocity, but rescaling of colors fixes that.
Just use a computer program and it's no longer difficult :)
This is how I used to visualise 4 dimensions. You could also other sensory clues such as roughness (visual hashing) for 5D but it is quite difficult. We have many senses we could use but integrating them is problematic. Ugh. Best to just abstract them I suppose.
The757packerfan It would be difficult to read.
Great video, I was able to understand almost every part. Keep making more of these!
YAY I WAS SO EXCITED FOR THIS
Benjamin Vroman me too.
same!!!!!!
I'm really glad for channels like yours exist for those taking up physics :)
Wow, this video was awesome. Really, really well visualized and explained interestingly. And the whole time I was feeling like "But how about-" and then you answered exactly that. Very impressive, I'm now hyped for the next episode :D
Love the way you worked the art in this video! Kept the look and feel of the channel, but made everything clear and easy to understand!
Amazing first episode Henry! Keep up with the fantastic work. I'm looking forward for the next episodes! :)
I love this channel and it makes my day to see it pop up in my notifications
This is 3blue1brown level of quality.
I don't know about that, 3blue1brown is in a league of its own in terms of the quality of the animations and presentation. But I will give Minute Physics credit that it makes much better use of cats. :)
@@Bodyknock he just keeps sending them to space and killing them in a box or a bunker, or teleporting & assembling and reassembling them;with flees;to the moon;. Also not to mention to send them in a black hole
Thank you very much for doing this!
Now I feel as excited for every new episode as when this channel first started.
10:21 Is it not (x,t)?
came here to say this
The convention is (t,x)
Oh my god this was amazing. I got into your channel probably around a decade ago with your videos on Schrödinger's Cat and other things, but I have become kind of nonplussed at many of youtube's offerings as of late with simplified videos not covering complex topics enough because they have to fit inside of a scant few minutes. I lived all 14-and-change minutes of this because it wasn't just blowing through everything, you actually took the time to explain what all was being considered. Thank you so much for bringing us this and I hope for some more longer-form videos like this in the future.
How do you find such compliant cats?
This is fantastic. I always knew the concepts of special relativity but this video brought everything together and suddenly made it click. You describe some difficult concepts in such a clear and concise fashion that even a child can understand. Keep up the great work!
After fully understanding special relativity, should we expect for general relativity on the list too?
mangesh burange general relativity would be awesome!
damn i love physics so much. Thanks for making the explanation easy
I feel like this should be the one video from MinutePhysics I was capable to understand and yet I'm still confused xD
Right now I am glad I took Physics and Maths as my most important courses! (However the school system is where you are.)
I really like that you took your time explaining things slowly with a lot more examples. The past few videos, I felt handled more complicated topics but rushed through them too fast for me to understand. This one is much much better.
World lines?
El Psy Congroo, my esteemed comrades.
Jordy3D it all the vision of steins gate assistant
Jordy3D Same
I'm commenting from the year 2036
Nice
xDDDDDDDDDDDDDDDd
I love that you are making longer videos on physics now. SR is a great place to start and everybody can learn it if they are proficient with high school math.
Another *minute* physics video
it is!!!
Thanks Captain Obvious!
I swear if u guys don’t get the joke I’m gonna internally die
Yep, fourteen of em
yeah not really a min
seems incredibly intuitive and self explanatory
unlike your usual videos
*great explanation*
Starting at 9:00 ... as a 3D animation hobbyist as well as an avid science enthusiast, the various timelines and diagrams are probably the one thing that is most intuitive for me 😁
Did mp forget the background music in this one?
This is hardly 14 minutes. This is about a one hour lecture in the subject as the speed goes. I like it. :)
What does the Earth Tellus?
I see what you did there. Latin nerds unite.
that you cant spell
carl scop
Whooooooooooooooosssssh! You know that sound?
carl scop r/whoosh
You clearly dont get it.
The build up to the most complicated theory of all time is absolutely superb !!!
Loved this series...
Minutephysics in this case is more quarterhourphysics
I like the way you really exactly point out the meaning of length ratios and the difference between numbers and physical quantities! This is really rarely done that deep, as it should be. I like the way, real understanding builds the foundation of your videos about relativity!
Excellently done. Although, once you get to using spacetime diagrams to solve actual problems, you realize how unintuitive it is because it's a non-Cartesian metric where a line segment can have zero length. I was hoping a clever mathematician could come up with a metric for it that's hopefully, more intuitive but I'm still waiting :(
Yes. I was looking for such a comment. Minkowski means you have to be careful when interpreting spacetime diagrams.
@@Overtime123 Nice usename
@@feynstein1004 thanks ;)
A 14 min video of MINUTE PHYSICS just made my day!! Eagerly waiting for next video. Plzzzzzzz bring it fasttt 😭😭💕💕
This some good stuff
MINUTE physics, uploads 14 minute physics video. Thank the lords
I use Spacetime whenever I want to video call my friends.
Continual Improvement lmao nice one!
When Kurzgesasgt and Minutephysics post a video the same day, you know it's going to be a good day
This has made my day
I don't think I've ever had a video make me think so much... I love this feeling of stepping into new concepts and ideas because I know there is so much more to learn, but it makes me sad because I still have to wait to learn this stuff at school. Welp, I hope my teacher does a good job at not making the subject frustrating. My friends always ask me why I learn this stuff and say I don't need to, and I know I don't need to, but for me it's the the best feeling to learn new stuff. Thank you for making these videos, Henry, and good luck with your projects :D
So ... I'm 5 Cats away from you!!
Schrodinger cats
Been patiently waiting for what feels like forever! Really excited for the rest of the series!
Alert: A complete neural rewiring is going to happen.
As a Physics major can I just say that you described the first few lectures of my relativity class (minus the math), in one video and made more intuitive sense while explaining this more easily than my professor ever did. Please keep these videos up, they're great (and great review for when I completely forgot my 8 Am relativity class--who schedules classes at 8 AM for such an intricate subject!?)
5:01 Great video. But is distance absolute in all dimensions ?? Like 3d OR 4D?
Yes. You can do the math if you like. It's not as complicated as it seems at first.
Aye. Represent your points in vectorial notation, and do the math. For example, if it is a translation, then the points would be a1 + b1 + c1+d1 and a2 + b2 + c2 + d2. Distance = √((a1-a2)^2 + (b1-b2)^2 + (c1-c2)^2 + (d1-d2)^2) . Now, in a translated system, points would be a1 + b1 + c1 + d1 and a2 + b2 + c2 + d2. Still, Distance = √((a1-a2)^2 + (b1-b2)^2 + (c1-c2)^2 + (d1-d2)^2) . [∆'s get cancelled]. 👍
Distance is simply a 1d line if you may.2d is made of infinite 1d lines to make area.and infinte areas would make a 3 dimesional volumes and so on.The point is no matter how many dimensions you take it is still a 1d line and a fundamental of any dimension so it won't change.
In any n-dimensional Euclidean space, yes.
Phúc Minh Nguyễn Lê so you r saying it won't be so in curved spacetime which is non euclidean space.i think it is in that one too.or "eulidian" is something else.
Definitely like the longer, deeper format!
Longest minute of my life
87246305I First hand experiencie of time dilation.
All this time I thought I had a firm grasp on special relativity. But from this video, you have convinced me: Special Relativity is all about how many sticks I am away from any given cat. Thanks!
As I sit here and edit my videos, I wonder to myself if the speed of light in a vacuum is the same for all observers, regardless of the motion of the light source?
10/10 self promotion... 9.5/10 your content
yes it does
Hahahhahha uhmmm yes
It does remain the same, indeed. It's a consequence (or perhaps cause?) of time dilation. Time passes differently from different moving perspectives such that they always measure light to move at exactly c when in a vacuum. Vsauce (or maybe Vsacue3) did a video on using headlights at lightspeed which does a good job at explaining this. Also, little fun fact, if you were to hypothetically move at the speed of light, time would not pass from your perspective.
Blak I would say the cause of time dilation
I would just like a moment to thank you for keeping physics fun.
Wish our teachers could learn to teach this way.
Great video! who would ever dislike this??
trolls
a robot "who" dislikes every video with over 300 likes in 10 minutes
The Usenet newsgroup sci.physics.relativity (groups.google.com/forum/#!forum/sci.physics.relativity;context-place=overview) is full of people who refuse to accept relativity.
Relativity deniers are almost as bad as Creationists or Flat Earthers, they're so annoying. The Electric Universe crackpots in particular are the worst, no matter how much evidence is presented that they're wrong they're convinced the only reason relativity is accepted and their quack theory isn't is because of a massive scientific conspiracy against them.
Relativity deniers. I personally think they're more fun than creationists to argue with.
This intro to relativity is extremely awsome. Thanx for creating this video.
Is it true that the time-energy uncertainty principle can break conservation of energy?
It doesnt really break it, in a time scale of the planck time it happens so fast that it does not break conservation at all
You don't even need uncertainty to break conservation of energy, in an expanding universe energy isn't conserved.
Doug Rosengard uhm what....
It's true, while conservation of energy is still the case in Special Relativity for a given reference frame, with General Relativity you no longer have underlying features needed for a conservation of energy law to necessarily hold. It gets very technical but essentially you can think of it as whatever energy causes spacetime to expand is being added to the system as a whole without taking energy out of the universe in the process. A universe with constant energy density throughout its volume and whose volume is constantly expanding is constantly gaining energy without losing energy elsewhere.
So as mind-blowing as it sounds General Relativity allowing the universe to expand also means it allows it to gain energy seemingly from nothing. There are other possible values that can be conserved under General Relativity but "energy" itself isn't necessarily one of them.
Doug Rosengard So first conservation of mass, then conservation of energy, is there anything school taught me that is actually correct? XD
I’m just 13 years old and haven’t even touched stuff like ‘cos and ‘sin’ but still u explain it in such a way that even I can understand.i had alway had a Interest for maths and physics but the way teachers teach us at school is too confusing. So while the teacher keeps reading from the book (and not understanding the topic him/herself) we are just left confused and if we ask a question,the teacher gives such a answer that we still don’t understand.Thank you for covering this topic and Thank YOU for making very enjoyable and interesting videos
I'm not high enough for this
You need to be at least 1.20 m high to get it.
Being high is relative.
+ Carlos Park
Wrong.
A person's height is defined as the distance from the person's bottom point (feet) to its top point (top of the head) in upright, erect position. And distance is absolute.
+Libor Kundrát He meant high as in under the influence of drugs....
+HeyWelcomeToMyWorld
It's just one of the two interpretations, and I was obviously referring to the other one. Wanna discuss and break down the joke further, so we can look more ridicilous in this comment chain?
Henry, you are amazing. I'm so glad you are a creator. Thank you so much!
Why go to college when you have this channel?
So you can put to test what you learn.
he just keeps sending them to space and killing them in a box or a bunker or trapping them in super position, or teleporting & assembling and reassembling them;with flees;to the moon;. Also not to mention to send them in a black hole
This is the best explanation about spacetime I have ever seen .
Linear algebra 💪
Amazing video! I loved the format, please do more of those ❤️
10:08 Steins;Gate anyone?
BenOfficial El Psy Congroo
weeb
I love how high quality your videos are. Keep up the amazing work!
EARTH IS FLAT! 10:42 - proof
You have done the work for future generations to simply and easily understand these concepts! Wow, thank you for this great effort, i mean i know you get compensated, but this is just elegant
Length contraction
This can make this video a big wrong in terms of physics
The video is correct in terms of relative distances on a graph remaining unchanged due to translation and rotation and scaling the axis. Bear in mind that 'length contraction" refers just to the spatial portion of a distance in spacetime (ie the x-axis) changing due to the transformation of the axes, but the overall relative spacetime distance between two points remains the same (ie the temporal y-axis distance is changing as well and the combined relative space-time length remains constant between two points.)
It's true for reference frames that aren't moving relative to eachother.
This video series is one I can really look forward to.
Ahh your series is a life savior for me! 😭😭😭 I've a physics test tomorrow, and I'm gonna sure answering relativity related questions. 😤😤
We perceive 'synchronized' time, which doesn't mean it isn't : 1st dimension + time + 2nd dimension + time + 3rd dimension + time, only, we perceive it as 'intersynchronized' depending on our relative position between any gravitational field and anti matter clusters, because there might have been multiple temporal dimensions before the big bang, which got structured into an interlinked 3D+ time within the electric perceived coherence on this level in our spacetime fabric orientation. And measuring 'time' is always done on this side of the atom, therefore it is presented to us as 'intersynchronized', once you break molecules down to a subatomic level, you can either measure 'position' or 'fraction', but that might just be due to this intersync breaking down of course. That's the reason why light has been more likely to have slipped between the second and the first dimension, rather than the first and the second, I guess.
This channel is to youtube what the "brief history of time" book is to science literature. Lots of important and sometimes complex concepts so easily explained.
Finally.
14 minutes was worth the wait.
Thanks for taking the time to do this series!
"Relativity is about understanding how changes in perspective do or don't affect motion." I love that.
The editing of this video must have been very very challenging. Really appreciate the effort. Also, plz do more of these series please
This project will be very helpful to everyone. Keep it up Minutephysics
Can you accelerate sound? Like is sound one set speed or does the speed of sound add to the speed of wind for example? And if yes, why doesn't this apply for light in a vacuum or a material, or even does it in material?
Nils Man the speed of sound is a variable - firstly due to the difference in density, i.e through water Vs gas or ice. Doppler shift is an interesting effect where the sound becomes stretched/compressed when coming from a moving object. I'm not sure how Wind speed would effect it though!
Wow, you guys just stepped up your game immensely. These videos are amazing and we’re learning so much! Keep up the great work!
You really get me into physics physics. Im procrastinating my physics engineering assignment a lot.
Finally. It's been over a month since chapter one! What have you been up to with Mark?
SUCH A GOOOOOOD Video. Probably the best special relativity video on the internet!!
At 10:20, the coordinates should be (x,t) as conventionally the x coordinated is written followed by the y coordinate.
5:58
Shouldn't that be the reverse?
Man, I teach conceptual physics as a course, and I'm very tempted to just play this video (and then the rest that come) when the chapters on relativity come about