Einstein's twin paradox explained - Amber Stuver
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- Опубліковано 6 чер 2024
- Follow two astronauts into outer space to explore time dilation and Einstein’s theory of relativity through the Twin Paradox thought experiment.
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On their 20th birthday, identical twin astronauts volunteer for an experiment. Terra will remain on Earth, while Stella will board a spaceship. Stella’s ship will travel to visit a star that is 10 light-years away, then return to Earth. As they prepare to part ways, the twins wonder what will happen when they’re reunited. Who will be older? Amber Stuver investigates the “Twin Paradox.”
Lesson by Amber Stuver, directed by Aim Creative Studios.
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I feel like this is the level of confusion that babies experience when looking at adults having a conversation
Same and so the first quote was an attack on us :(
@@shiningstar2843 so we are the cat ?
Hahahahah
😂😂😂
Wrong.....this is the look of adults listening to babies talk.
"Terra and Stella now both have a better understanding of how spacetime works"
Me : Ok, but I don't
Light-speed traveling equals Time-travel into future
Have in mind that Stella was already an astronaut to begin with. So they were a couple of steps ahead
Terra? Stella? Hey, I just got it!
"Terra and Stella now both have a better understanding of how spacetime works"
Me: "you'd think they'd have an understanding BEFORE becoming astronauts.
Bruh. Are children suposed to understand this it’s on ted ed
Thank you. You saved my life. I had no means to cook food this morning but after watching this video I was able to cook my breakfast on the top of my head as this video set my brain on fire.
🤣🤣🤣🤣🤣
This was a genuinely good joke lmao
that was genius
I was watching this at work (slow friday) and freakin laughed out loud. Goddammit. 10/10
😂😂😂👌
What I’ve learned: I’m as smart as a cat.
cats are smart
I would aim even lower.
Something like this
Assuming that your cat is good at sarcasm 😁
@@sandippaul468 (Thank you. You saved my life. I had no means to cook food this morning but after watching this video I was able to cook my breakfast on the top of my head as this video set my brain on fire ) this yours?
Imagine telling someone you're twins, and them saying, "oh, who's older," and you being like, "Terra, by 11 years."
Orange juice noise
Grucci _ *noice*
I was in a important lecture and out of no where I bust out
Ginny Potter wait the video is basically saying you age slower in space than in earth
Rest is history
Imagine not having contact for a year only to receive a message saying “your fish died”
Four years actually. You need to pay attention.
And you responding some 20 years later :" Oh no! I am coming back home right away "
Theres a famous story of a British Submarine in the war that used to tey to surface each week minimum to get the news on the BBC World service.
One week, they detected a German boat and had to delay their ascent.
When they did surface, they caught the very end of the broadcast which was "Arsenal, nil"
@@zachbailey457 Its a J O K E
@@havesomerubicon6097 jokes are funnier when they make sense
I love how they reunite and how surprised stella looks when an apple falls because it has been 11 years since she has experienced earth gravity
Wow. You have incredible observation skills.
This video reminds me of when I came back to class after missing a few important days.
If I ever have twin girls, I'm naming them terra and stella and telling them stella gets to be an astronaut but terra has fish to babysit
If you are unaware of this comment, I will tell you that this comment has blown up to over 1k likes.
This made my night thanks
I think she meant Tara not Terra
@@shahinazmeerriza5377 It's Terra. Terra means earth, while Estella means star. They are Spanish words derived from Latin words with the same meaning.
@@reinebautistamercado4286 Thanks for explaining ❤️
I knew terra was Italian for land but didn't think about Stella
Doctor: you have six months to live
Stella: lets make that a year
Let's make it infinite!
md ridoy that’s what I was going to say!
Thats not actually how it works, is it?Youre still going to die in 6 months, but if youre in space and travelling close to speed of light, youd still be dead in 6 months but a year would have passed only for non moving people on Earth.If i understood it correctly.
@@TheNighKnight yeah
Stella will be dead in 6 months but to everyone else she will die in a year
Special relativity is making a 6 minute video feel like an hour long
For reeaall
Exactly!!
Oh I get it now.
Terra -> means "earth" -> stays behind on earth.
and "Stella" -> stellar -> stars -> goes to space
That's all i understood though
Imagine sending a message into space, waiting 2 years to only get a "👍" back
That would be my dad
@@zuigeenlul lol
Or an “lol”
Ok
Or being left on read.
Imagine saying "Yeah she's my twin but she's 11 years older than me"
Fantastic thought 👏
how?? can you explain it?
"Yes, she's my mother, but I'm 20 years older than her"
@@bursendogan2338 Did you even watch the video?
@@cinegraphics 💀
"We`re twins!"
"Really? Who's the older twin?"
Terra: "Me, by 11 years."
lmaaao
For people who do not understand, basically the twin paradox is where the saying that time goes slower in space is challenged, when in reality it goes extremely slow in the beggining and extremely fast at the end, equalling it out.
thank you so much, so does that mean they are gonna be the same age biologically?? and those years lasted the same amount of time for both of them?]
@@Tolafasolaxd No. As the video explained, they are biologically going to be 11 years apart, when stella returns from her journey.
@ezmeeplays2125 is wrong in saying that it all 'equals out'
@@Tolafasolaxd no. only the perception equals out. the biological truth bears the difference, since the one on the ship would age slowly because time itself is moving slower on the ship. when i say time, i mean physical time, not just theoretical time.
think about it this way. Stella on the ship would have her cells divide more slowly. Terra on earth would have her cells dividing faster, which is why she is going to age more while Stella will be younger.
Why would stella still be younger by 11 years at end tho?
It doesn't equal out. Stella is more than 10 years younger than Terra because she flew at 86% of the speed of light. If Stella flew slower they'd be closer in age, except it would take so long that they would both die of old age before seeing each other again. The human lifespan is too short for space travel. If we can live longer then it can be possible but this doesn't refute the fact that faeter travel means slower motion. That's what it comes down to. Slower motion means slower cell turnover which means others will die before you because their cells moved more than yours. Less motion means less aging.
“Your fish died”
“1 year old, r.i.p”
how is the fish 1 year old if the message is after 1 year idu
GaBoX17 DA the text says "1 yr old rip" as in "this rip was sent 1 yr ago"
@@darkboy2216 but stella receive it many years later so yeah
@@farrel_ra ya so for terra 2 yrs had passed
1st yr - msg frm terra to Stella
2nd yr - msg frm Stella to terra.
Many year passed in earth where only 1 year passed for stella
Teacher: Don't worry class, the test is going to be easy.
The test:
yess
But this is easy
@@randomfacts9588 Well no it was quite confusing
The spelling test is fun
@@vedantsridhar8378 actually it's pretty simple
This is the best produced Ted-Ed animation I've seen. The music and the animation are beautiful.
Loved this! Thanks Amber for the amazing video
For everyone not getting it, we're the cat in the quote at the beginning of the video.
That's the only thing that I understood! LOL
I feel like the video is more about consequences of this not why this exists. I mean they talk about how the twin see the other one and where time goes slower but i didnt get why. Only this formula at the start saying that "faster u go, slower the time". Mayeb i missed sth or its just too complex to explain.
wise words!
I had an exam on general relativity and this is literally the topic that took the most for me to grasp
Meow?
Here I was thinking "Oh! So they'll both end up the same age when they're back together" and getting it completely wrong means I understood pretty much nothing
The same
*but both twins know that it’s not that simple*
No offense but that line was meant to be for you XD
its pretty simple she is traveling at 86.6% of the speed of light, thus due to special relativity she experiences time twice as fast. thus it will take 11.5 years 11 years* where for the other twin on earth the journey takes 23 years
@@Serquest how can you say Terra has zero inertial reference frame relative to the universe. There is no absolute zero velocity reference point in the universe that everything else is moving relative to.
So Terra and Stella from each persons perspective, Stella is moving at 86% C away from Terra or Terra is moving at 86% C away from Stella.
I don't understand the explanation of the paradox.
I think you’re getting mixed up between velocity and acceleration she is in a non inertial reference frame relative to the universe that’s where the paradox comes in the part that’s overlooked is that when she changes directions she forgets to account for her new reference frame
Wait so Stella actually physically aged slower and is biologically 11 years younger than Terra ? Like in appearance and anatomy and all? That is absolutely mind blowing
Correct, it’s the poor man’s hyperdrive.
NASA already did this with the Kelly twins ( one now a senator ).
Same thing happened in the movie Flight of the Navigator. I loved that movie as a kid.
@@AMC2283 wait but in documents they are the same age??? Did they experience time differently? I dont get it:((( Lets say hypoteticly they both are gonna start playing guitar, one on the space ship and other on the earth, and lets say that learning it goes identically for both twins, so does that mean that tera is gonna be much better player then stella when they reunite??
@@Tolafasolaxd if you need a year of lessons to get good, terra will be better, since a year for terra could be a month for Stella
VERY WELL DONE. The graph made it so easy to understand.
Normal twins: oh let’s dress up alike and confuse everyone
Terra and Stella: hold my beer
😂
Underrated
Oooh blblblblblbl🧎♀️🧎♀️🙇♀️
🤣🤣
Terra and Stella : Hold our dress
@@pokechannel9758 ?
Don't worry if you can't understand anything in 6 minutes ,it took 23 years for terra and 11 years for stella to understand 😂
💀💀💀
Took me a year just to understand who was Terra and who was Stella 🤣
Terra is Latin for Earth, & Stella is Latin for Star. Their names correspond with their location
@@Caiyde 😯 oh nice
@@Caiyde yes, clever, but their names sounded very similarly and were mentioned very often. They should have gone with very different sounding names or label the little faces on the screen.
This was a fantastic refresher of my college quantum physics unit. Succinctly summarized a few weeks of lectures into a few minutes.
One thing that's subtle and may further make difficult to understand is the following fact: Stella is moving at the speed of 86% of the light you have to keep remembering that so by the time the light signal from terra covers a light year, Stella would have further moved and the distance between the signal and her would be 72 % of a light year and so on so forth. Hence in about 7 years the first light signal reaches her.
THANAAANK YOOOUUU
But isn’t the whole premise of c being constant that I can’t tell how fast I’m moving by how long it takes c to reach me? C moves towards all moving objects at c, no?
I didn't understand that until my cat explained it to me.
this should be top comment
Did you stole the cat from Schrodinger?
HAHAHHAHAHA
Damn that's a good weed indeed
is it dead
As a 42 year old, I'm slightly offended by how old you made 43-year-old Terra look.
42 likes damn
I think that's the result of pollution on Earth rather than her aging itself! So don't worry, if Earth stays greener, you stay younger!!
Hahaha right!
@@PingYJ7750 443 now loll
Ok boomers😂
This is a great explanation, it’s about as simple as it can be made to be!
I’m always so intrigued by relativity theory. I just can’t wrap my head about it… perhaps one day, technology will advance so much, that we can experience it in one lifetime. 😌
the key is the word itself- relativity i understand whats going on with relativity but what freaks me out is knowing that something out there is happening simultaneous to this exact moment but due to vast distances that the light reflected off it must travel for us to see it it hasnt happened yet
Meanwhile, I'm here confused about which one is Stella and Tera.
stella=star, terra=earth
@@aidenaune7008 Yeah, that's how I remembered
Same
yes same
@@aidenaune7008 en español: earth - tierra, star - estrella
I love how their names represent where they are! Stella (meaning star) for the astronaut and Terra (meaning earth) for the one at home :)
I couldn't even understand which one was on Earth and the one in space
underrated comment
wow
never thought of that.
you have a great mind
@@meshackmuli2809 Terra was the twin on earth and Stella was one in space
Im calling the fbi
One of the top 10 videos on UA-cam!
This is why I always accelerate when running. Start slow, accelerate constantly, and keep the warm-down short. You will age a little less.
Same with driving.
I didnt know Einstein had a twin named Paradox
You don't know the great Paradox Einstein? He had the famous math formula E= MC² ≠E
😑
Hi, i like ur profile picture, its the same as mine, god loves you😊
Ya he was the old guy in ben 10 that learned how to travel through time
If Einstein will see you comment he will die again
"Stella" means 'star'
"Terra" means 'Earth'
Well that's one easy way to distinguish them! I forgot which is which along the video
Is it Spanish or Latin @Yan Wong
Perfect, as everything should be.
@@princezhedricksilvestre8168 latin. In Spanish star is "Estrella" and earth is "Tierra"
Thought it was pretty obvious...
While reading my Physics textbook,I had this exact confusion,now I am clear.Though I dont understand it deeply,you guys has solved my confusion❤
For anyone who doesn’t understand the graphics. Remember that Speed = Distance / Time and in this instance, the speed of the light-message will be constant.
Huh?
Watching this and I was like..
"Damn, I'm dumber than I actually thought I was"
Same
i already knew this...i watched because i'm bored
too many distractions to think this one through
It reminds me of this conversation from one of the Discworld books:
-He was a good, clever kid. To be honest, before his lectures I never really understood magic
-Me neither. But do you now?
-Well...no. But at least I know how much I don't know now
The two mages then felt a surge of pride from their ignorance being superior to the average person
Nope, the video just didn’t explain it properly
“Terra and Stella now both have a better understanding of how spacetime works.”
Good for them because now even the only functioning brain cell I have is malfunctioning.
😂😂
Whenever I get this feeling that I might be good at physics, I watch this video to humble myself
Really helps
Thank you.
I can still never wrap my head around this concept.
Noone:
Absolutely none:
Terra: i BoUghT yOu a fIsH
very funny right?
hahahah i died laughing
@@HeLow005 R.I.P. only 1 year old
“Your fish died :( “
LMFAO 💀💀
POOR GUY just like the fish
Everything was alright untill stela left the Earth 😵
She should never have left. lol 😂
**returned** to Earth. It's the change in reference frame and bringing the two twins back together that makes one definitively older than the other.
:D
😂😂😂
That's quite... Well... Stella(r) ;)
It took me over half the video to realize their names helped you know which one was in space and which one was at home because Stella=star and Terra=earth.
This just makes me believe even more that I have already lived this life, but only now I am experiencing it in Earth time.
smart of you to name them "terra" and "stella" for "earth" and "star" so we can easily remember which is which
I def didnt remember either ones name when i made a terrible comment about earth being flat lol
It took me half the video to realize it and I am fricking italian
And you're still beautiful...😍
Yea im able to tell them apart because they have completely different names
They (Ted Ed) always do this. Specially if you check the Riddles, they have names starting with A, B, C... like typical math variables.
5:47 "Terra and Stella now have a better understanding of how spacetime works"
oh good that makes one of us
two*
Honestly i think i understand it less. I'd heard that time changes speed when in space. Fine i don't get it but it's none of my business
Now theres all the details that i'm not going to remember the order in but i'll still try to spit it out as a thing i know and get it super wrong.
Ikr
I'm a physics teacher now and I can't believe how few years ago I passed the subject special relativity at university lol.😂 I understood half of it but now after teaching, I understand it all.
I don't understand what happened in this video but I'm glad those twins are happy and learning things :)
"Wibby wobbly timey wimey stuff"
I see the writers are people of culture
@Manan Karnik it's from doctor who
Naw that’s just how British people really actually speak
@@BusterDarcy Indeed it is how we speak
Whovianssss
Where in the video?
Still very confused, but on a much higher level now. Thanks.
@Belial Made it confusing on purpose? They're _"Explaining"_ it in a more detailed, technical way. Why? Well because as you already said, you already knew the answer. But then, _how can it be the answer?_ That's is what they're on about. Also no, it's not really that confusing - I suggest you to give it another try.
same
Loool saaammmeee
they dont understand the root of the peoblem themselves
lmao my name is stella so I'm even more confused, dude
This is best twin paradox explanation on youTube.
But it's wrong.
Great Scott!!
Me: Lets watch this video to understand the Twin Paradox
Brain: Error 404 - explanation not found
Catastrophic error
🤣🤣🤣
Bruh same, i even bought a comic kid about this thing and still confused
Normie
@@ohcool8314 bassicly the faster you move the slower you age Terra was not moving but Stella was (relatively) and because time slows down the faster you move Stella is younger
Moving = younger
Stationary = older
1:18 -> me trying to understand this Ted Ed video
#relatable
im screaming 💀💀💀
Yup
"Uh huh, oh yes of course, makes perfect sense ... wtf is she even saying!"
@LagiNaLangAko23 same po, 😂
Love the choices of names
Best explanation I found!
has that one opportunity to send one message per year to twin: "I bought you a fish"
theEXOaudio genius
114 years today since The Theory of Special Relatively was published!
114 years? ... Or is it?
**Vsauce theme plays**
Its 100 years older than me
115th like
Depending on your frame of reference
@@night_mare_1172 same
amazingly explained
Loved the doctor who reference at the end!
"They both have a better understanding of how spacetime works"
Good for them. Meanwhile me...
Copied😒😏
Correction "us"
This was the most confusing 6 minutes and 15 seconds of my life.
Really? It was only about 3 minutes and 7 seconds for me.
@@weckar are you watching this from space then?😂
@@Ariadne4 no they just watched it at 2.0x speed
ON GOD 😂😂
Im like half asleep rn so it makes even less sense
A beautiful animation again.
Good morning . Waking up to this in your recommendation after a super typhoon is....
I'll pretend I understood everything
this, lmao
Swastik Sahu. Same
Honestly, this is a mood whenever I watch a Ted-Ed video
lol
@@sarahnunez318 me too
All I got from this was a prime example of sibling rivalry.
Like, who tf goes to space just to prove a point
That's the exact reason the U.S. went to the moon :)
Teacup _ ikr it’s not like it’s an example or anything
@@okas425 its not like it's a joke or anything either right? 😂
I’d totally do that to my sister. Since she thinks she’s soooo much better. I went to space!!! I’d rub it in her smug face!
Teacup _ It was more of a hypothetical statement but if it’s intended use was a joke then sure why not
This is mindblowing
And the fun part about all of this, is that all of this can be logically concluded simply from the fact that the speed of light is constant. (Which we found out basically by seeing that no matter how we measure light in vacuum it's speed is constant.)
The cure to anti-aging: live in space and never come back
Actually you age at the same rate for you but slowly for others...
@@vandanaasthana1216 Yeah, but from the perspective of someone on Earth, you'd be much longer lived.
@@Lord_Of_Night and how does that matter to you?
@@ni3070 It doesn't. I was just pointing it out.
But why you didn't have boyfriend/girlfriend in space?
Whew, the relief I feel reading the comments and realizing I’m not the only one that gets everything and nothing all at the same time. Thanks guys!!
Lori Williams I don’t get any of it.
I won't push the like button cause the number is nice
@@nurindahsaloka9491 i missed it what was it at😂
@@adambaker4581 123 😂
Yeah like you got the ideia, but have no understanding of the science behind it XD like spaceship goes swooooch very fast and then very slow and batabi batabo they are 11 years apart
I was confused about all this before watching this, and now I am way more and more confused. Thanks!
Okay but a book about some twin sisters separated one in space one one land and having an emotional scene of one sister seeing each other at the end at different ages at the end would be amazing
Wibbly wobbly timey wimey like.
David tennant just sneezed
Whovians are everywhere 👀, even in TED-ED
Allons-y Alonzo!!
I read your comment right at the moment she said it. XD
GERONEMOOOOOOOOOOOOOOOOOOOO
I’ve just realized that this could be a time machine. Go into space for 10 years, see the earth 20 years later.
That's the general outline of time travel
You can't go back tho
depresso
thats basically the movie interstellar lol
That's absolutely correct. In fact, even people who spend a lot of time traveling at a high rate of speed, such as flight attendants, do in fact experience a slower rate of time than others. But that's only as a miniscule rate, adding up to a fraction of a fraction of a second even over the course of a lifetime.
modern rocketry is faster but (I think) still wouldn't cause more than a few minutes of "time travel" after a journey of years.
Yes but to truly travel time you need to get time to go backwards too
I couldn’t imagine being away for that long
God the concept of time is so fascinating
*me 2 minutes into the video*
"so which is stella again?"
Stella = stellar = relating to stars = in space
Terra = terrestrial = relating to earth = on earth
Lol hahahha
@@donkberg fascinating
"Terra" meaning Earth stayed on Earth, wheras "Stella" relating to stars went to space. Love that clever addition!
finally someone noticed that!
The only thing I completely understood in the entire video
Smart you are!!!!!
this was the only thing thst made me feel smart in this video
Stella in my country is a beer
This is a very complicated explanation of this paradox.. The paradox is actually very easily understandable
I didn't even notice when the video ended !
Them: Her journey should take 23 years
Me: Great! That seems pretty straightforward.
Them: Pulls out the real science
Me: Brain no work
Aaron L. I thought planet of the apes was about the Simian Flu and it’s infection of humanity in an attempt to cure Alzheimer’s. Are we thinking of the Dawn/Rise/War of the Planet of the Apes? Or something else entirely?
So if you travel faster than light... would that mean you are able to upend time backwards?
@@lued123 Does antimatter contain negative mass?
@@lued123 so why is antimatter anti?
“Let’s pick the most convoluted way of explaining time dilation with the cutest animations.” Them, probably.
@@erikchristian3894 I also thought the graph was excellent. I do see why many people struggle understanding this video though because it doesn’t actually explain what special relativity is and how it works in much detail at all. This video is great though once you come back to it after understanding SR.
It even gets the answer wrong after all that ....
Yeah, this was pretty rough. I'm still struggling with accepting that it's at all okay to directly correlate the time between light pulses with the speed of aging since we're accepting that it's artificially changed by whether you're coming or going.
Maybe that was the point, but if you're using faulty data why should I trust a conclusion reached from it? I don't know, something feels off with this explanation. I probably just need to research the subject more prior.
Somewhere in this video my mind when somewhere else but i still watch to the end
Finally! I almost understand it!
Came to feel smarter....went away feeling like the cat they talk about at the start...😂😂😂😂
Underrated comment
i swear i actually restarted this to see the cat
Ikrrr
Same lol
😂😂
I felt like Chidi trying to understand the dot in the “i” of Jeremy Bearimy while watching this
Jo Roz I love how I instantly got this reference
the good place fans unite :)
perfect example
What's chidi
this was the perfect reference, i just finished the last season today
Their faces are hilarious. 😸 A good explanation.
I didn't realize that directionality of motion affected the lorentz transformation and that a different reference frame moving at high velocity could see the other reference frame's timing passing faster. Now I'll have to study this again.
Whenever I have trouble sleeping , I watch this video and fall asleep halfway through it
Genius. I will do the same from now on
🤣🤣🤣
Saving it for that
@@vedantsridhar8378 Bruh why you be stating the obvious ?
Whenever I have trouble sleeping, I watch this video only to realize I'm 3 days awake just by understanding this
*Terra:* I'm feeling sad, I'm not sure I can do this anymore.
*Stella:* Apologies for the delay are you still there?
i actually laughed out loud at this
Oh my
This one got dark...still funny though
Wonder what that says about us....
lmaoo these comments are gold
I studied all that in high school it was easy to solve on papers but hard to explain orally!
this animation is beautiful
I like the names terra and stella, makes it easy to remember which is which.
Oh I just realized. Stella went into space and terra stayed on the ground. Huh. I found it super confusing cuz I couldn't keep track and kept forgetting which was which. But now that I see this it makes it so much easier to understand
is noone talking about how the fish died
Because time flows too fast
Oh 2:43 🤣😂🤣😂
Rip fish
it was a car accident
drunk driver. they say he drank like a fish
I always thought that the light clocked worked like this. The first half second is the up path and the second bounce back is the second half of the second to equal one second. Shouldn't Stella's round thing in the graph be a mirror to to mimic Terra's mirror?
Interesting theory video on time travel