We made quiz questions to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: apple.co/3d4eyZo Download it here for Android Devices: bit.ly/3TW06aP
@TheSnakeboy115 жыл бұрын
"You already know that V x T = D" *you overestimate me*
@_zerofox4 жыл бұрын
This is too funny XD
@mrhatman6754 жыл бұрын
Sorry but that s as easy as a squack
@neetbucks5214 жыл бұрын
I think they are speaking to you as if you are watching each episode chronologically that concept was covered earlier in the series
@rld82584 жыл бұрын
No you underestimated yourself
@VyvienneEaux4 жыл бұрын
I’m pretty sure you did already know that one. I walked at a speed of 3 miles per hour for one hour. How far did I go?
@jessicaonymous43525 жыл бұрын
0:23 I love how Bob is flying backwards, presumably from air drag, even though he's in a vacuum
@dr.bipinmandar34586 жыл бұрын
After watching this, I realized why Einstien is regarded a genius.
@rh167 жыл бұрын
My mind is so fucked right now i forgot how to hold a spoon
@RatherBeEmbed5 жыл бұрын
There is no spoon lol
@ChimneyCrab7375 жыл бұрын
RatherBeEmbed is that a gamechild reference
@staubsauger23054 жыл бұрын
@@ChimneyCrab737 - is from the movie The Matrix.
@guigaingamkamei96544 жыл бұрын
I'm dead lil
@varinderarora32384 жыл бұрын
spoon!! how to breathe
@twentytwo12905 жыл бұрын
My bicycle can't travel faster than light, it's two-tired
@guigaingamkamei96544 жыл бұрын
I see the pun
@michelef4064 жыл бұрын
So underrated.
@taseenahnaf4 жыл бұрын
@Michael Terrell II tyre = tire xD
@randomstuffyouwontseeinyou87864 жыл бұрын
I don’t get it
@jeremyjohngraham4 жыл бұрын
😑🤣
@JugheadJones037 жыл бұрын
Dr. Somara, I cannot imagine how mindbogglingly hard it must have been to get through all of this in school and UNI. Thanks for trying to make this palatable for people like me who are fascinated by it, but just not driven enough to take it on! Really cool stuff.
@AndroxDpl7 жыл бұрын
Jughead Jones She said at the beginning of the course, she studied fluid dynamics. Which is still a bitch, because the math gets very complex.
@TheScientificCookie7 жыл бұрын
Special relativity can be taught at secondary school its quite simple. Fluid dynamics on the other hand...... oh dear god save us all.
@fossilfighters1017 жыл бұрын
+
@anirudhkrishnan17977 жыл бұрын
Wojciech Morawiec 😂😂😂😂
@mayankgupta73426 жыл бұрын
Jughead Jones yups I think the same!
@fernandes14316 жыл бұрын
How Einstein conjured this madness up. Wish I could :-D
@equivalenceprinciple19824 жыл бұрын
L F The speed of light in a vacuum being constant is actually a prediction of Maxwell’s equations, which describe electricity and magnetism. Einstein computed the effects of this in Special Relativity. In addition, there was experimental evidence at the time that seemed to indicate this fact about light. A famous example comes from the Michelson-Morley experiment, which tried and failed to detect the ‘aether’, a special medium in which it was thought light travelled. This in no way diminishes Einstein’s achievements, however! To paraphrase Newton, everyone stands on the shoulders of giants.
@rustysim6 жыл бұрын
English is my first language and she still spoke fast as hell...
@spookeymo6 жыл бұрын
that's the first video on spcial relativity that explained it so well i understood! most people don't include maths in their explanation because they think it'll make things more complicated but it actually made it so much easier to comprehend. thank you for your series!
@alekdaniels4 жыл бұрын
I just dropped by to tell you I'm only looking for a special recipie to cook for relatives and got subjected to a serious mental injury by clicking this video.
@swiftlymurmurs7 жыл бұрын
Man, that is... Mindbending. We're used to thinking time and space are constant, and can't be shaped to our will. But when you realise it's all conatantly warping and stretching it gets... a bit confusing
@TheDemisemismiles4 жыл бұрын
Subhobrata Chakravorti Einstein didn’t invent, he discovered.
@amosandrecantini34535 жыл бұрын
I'm the only one who's watched this video twice and lowered the speed to 0.5 to understand something??
@iaexo4 жыл бұрын
0.5c
@DavidGonzales-eq2oi4 жыл бұрын
Don't forget closed captions!
@erkive22014 жыл бұрын
I did and still didn't understand anything 😂
@katejohnson97374 жыл бұрын
But from the perspective of the video, it perceived you observing it twice as fast.
@manofcultura7 жыл бұрын
Is this real life or is this just fantasy? Caught in a land slide, no escape from reality.
@drg86877 жыл бұрын
Open your eyes, look up to the skies and see..............................
@Mr8lacklp7 жыл бұрын
Jebuslives mom's spaghetti
@vikneshmaniam56187 жыл бұрын
im just a poor boy i need no sympathy
@vikneshmaniam56187 жыл бұрын
brendon's version playing in my head
@afroman86267 жыл бұрын
Mr8lacklp- Nice, love the Queen ref destruction. Good old EMINEM
@matyourin7 жыл бұрын
nothing gets easier to understand by telling it faster... while I somehow enjoyed crash course history and philosophy, these physics crashes just seem to me like a futile attempt to reduce complex topics and speed them up to make them somehow fit this format - so that the result is only understood by those who alrdeady understood it in the first place. maybe that's just my impression as a physics teacher...but I would take a complete series of videos instead of one to get each of these topics.
@oldcowbb7 жыл бұрын
i recommend drphysicsa, he explains really well, and i like his accent
@j-theorythequantummechanic60257 жыл бұрын
matyourin Or read The Elegant Universe..
@mfpope74316 жыл бұрын
j-theory the quantum mechanic I’m reading that right now and I just got done with the general relativity section, and still don’t understand it. I mean I understand that time changes according to the something is going, but I don’t understand why. Maybe my understanding of time is wrong or something. But I watched this video to get another point of view or explanation.
@davidscott59036 жыл бұрын
I fully agree with you. This covered the topic about as well as a Hollywood movie, but most likely just scared more people away from ever really learning about it. Most people are going to watch it and say to themselves, "Wow that was a lot, and I understand that time changes based on how fast you're going, but I don't understand the rest, so I guess I just can't understand that and I guess that I am just not smart enough to learn about that." And that's when they decide that they can't do it, and quit trying.
@paulpaul88615 жыл бұрын
I don't understand the need to speak so fast. It doesn't make it easier to learn, so not sure who it's benefiting.
@benhurston4 жыл бұрын
I've watched several videos in attempt to understand special relativity/time dilation, and either (a) all of the previous videos have been slowly adding to my understanding to the point where when I watched this video, it finally made sense, or (b) this video does the best job of explaining special relativity that I've found yet! It's probably a little of both, but either way, great job, and THANK YOU!
@Kithairon7 жыл бұрын
If Bob is moving at a constant speed through a vacuum, why are his arms draged behind him?
@Basilisk20776 жыл бұрын
Probably going insane due to the high g's he would be experiencing.
@charlesreisner66816 жыл бұрын
Warlord25100 that would assume that he is not moving at a constant speed. G-forces require change in velocity
@Basilisk20776 жыл бұрын
Charlie Reisner He had to get to that insane velocity somehow.
@o.p.rajput6555 жыл бұрын
Umm.... Why is no one mentioning inertia here ?
@abduljawwad16205 жыл бұрын
um inertia?
@luizbertoncini7 жыл бұрын
westworld anyone?
@JP-yl4ts7 жыл бұрын
Cole Sawyer same
@wmjessemiller7 жыл бұрын
yeah... i caught that too lol
@theazkii7 жыл бұрын
Luiz Bertoncini why?
@ThZuao7 жыл бұрын
Sort of. Not enough BOOBS.
@manojj8887 жыл бұрын
Luiz Bertoncini same thought
@oliverlovelltas4 жыл бұрын
Hi. I believe that one of your examples is incorrect. At 6:36 you say, ‘We already know that time moves faster for you than for Bob. Whilst 666 nS has passed for Bob, only 577 nS passed for you.’ These two sentences are contradictory. If ‘time moves faster for you than Bob’, then the amount of time elapsed for you (person on the platform) must be greater than for Bob. The time elapsed for the observer on the platform should be 769ns, not 577ns. This is also consistent with the twin’s paradox and the idea that ‘a moving clock runs slow’. From the twins paradox, we expect the observer on the fast moving object (in this case, the train) to age less than the stationary observer (person on platform). Thus, time elapsed for Bob on the train must be less than for the person on the platform. From, ‘a moving clock runs slow’, we also anticipate that Bob’s recorded time will be less than that recorded from the platform. To summarise, if Bob records 666 nS from the train, you record 769 on the platform. Happy to be corrected, but I believe that this is correct.
@bradyblake65737 жыл бұрын
been waiting on these types of vids for a while. I love this kind of advanced physics
@Teo-uw7mh7 жыл бұрын
Brady Blake this is as basic as it gets compared to generell relativety. But i guess you're not studying physics
@colbillington7 жыл бұрын
kevin randleman and I guess you're not studying grammar
@bradyblake65737 жыл бұрын
Thanks Was, also Kevin I'm graduating with a mech engineering degree in 8 months and I still find relativity goofy af
@IceMetalPunk7 жыл бұрын
+kevin randleman And general relativity is as basic as it gets when compared to quantum mechanics. Just because there's something more advanced out there doesn't mean everything else is basic.
@amritanshuray7 жыл бұрын
Yeah, but this is relatively more advanced than the previous episodes. Woohoo, hope you caught the pun. K bye.
@Donezekiele7 жыл бұрын
Did anyone else see a resemblance between the animation with the train and Westworld?
@dorkmax70737 жыл бұрын
Juan Vallejo Doesn't look like anything to me.
@atombaxter19757 жыл бұрын
Juan Vallejo Yes! That's what I thought when I saw the thumbnail!
@veggiekeef7 жыл бұрын
Dominic Sosa Perfect comment lol
@mihailung17207 жыл бұрын
Juan Vallejo How van you possibly believe that was not intentional? And yes, literally everyone saw it
@jeza81387 жыл бұрын
No. No one saw it. It's really hard to spot. You must be so clever to have spotted it.
@Worgak5 жыл бұрын
Oh my god, Special Relativity finally makes sense! I've tryed to wrap my head around it several times now, and had it explained to me in several diffrent matters. Yours is the one that finally made it click! Thank you so much! The world is confusig as ever, but at the same time, it makes just a little more sense to me.
@Worgak5 жыл бұрын
No, seriously, yall are the best. Thank you so much. You're wonderful.
@anamwaseem66935 жыл бұрын
I still don't understand special relativity 😭😭
@asoor13 күн бұрын
This video is pure gold! Thanks for the clarity in the explanations and the amazing motion graphics that accompany them.
@dorkmax70737 жыл бұрын
Thought Bubble...doesn't look like anything to me.
@toffeesky62277 жыл бұрын
I see what you did there
@abandonedchannel89817 жыл бұрын
Thomas Binch I dont
@CthulhuFhtagn1387 жыл бұрын
nah its just a "WestWorld" reference
@benjaminazmon7 жыл бұрын
Dominic Sosa, what do you mean?
@abhinavajith927 жыл бұрын
Chris Todd aha thanks m8
@atombaxter19757 жыл бұрын
Westworld influence in the animation?
@Nablabla17 жыл бұрын
at 0:30, when the train is moving in a vacuum, why is Ford dancing so crazy?
@timothymclean7 жыл бұрын
Have _you_ ever ridden a relativistic train in a vacuum? That's not dancing, that's spasming.
@fossilfighters1017 жыл бұрын
+
@claudettedelafayette99794 жыл бұрын
Inertia The resistance to sudden changes in motion. Just like pulling a piece of paper below a glass of wine in a short amount of time.
@matthewdockter24247 жыл бұрын
You guys did a good job on explaining this. This and PBS Space Time are two great videos on the topic.
@GuyusSeralius4 жыл бұрын
Wow, she talks near the speed of light! If only she was traveling near the speed of light, relative to me, then I would observe her time dilate, which would cause her to speak much slower from my point-of-view, so I could more easily take in all that she is explaining.
@samjw19997 жыл бұрын
This stuff is fascinating, why my class chose to do astrophysics over this I'll never know.
@nasserderakhshan32116 ай бұрын
Why are you speaking at the speed of light?
@splitpitch5 жыл бұрын
i can't wait until they start mass producing these new hypothetical trains. It will cut travel time immensely.
@timwhite17837 жыл бұрын
This was perfectly timed. I just started special relativity in Year 12 physics yesterday.
@harry_page7 жыл бұрын
Year 12? Mate you're so lucky, I'm in year 13 and my physics class does its best to avoid even calculus for some reason, it's quite depressing.
@wackywally694206 жыл бұрын
Year twelve is I'm assuming like the year after senior year in high school? I'm only in my second year of high school/secondary school and I'm really hoping we do more than just Newtonan physics and math only relating to that.
@wackywally694206 жыл бұрын
Grade 10 I mean lol
@AbdulBasit-we9lf5 жыл бұрын
Einstein was, without a doubt, in a league of his own. The simple fact of light travelling in a constant speed was taken into consideration, yet he brilliantly revolutionized Newtonian physics by applying certain case scenarios which were, back then, impossible to allocate to. Pure genius!!!!!
@megametagrossard33424 жыл бұрын
@Justa Fool that is only if the speed of light were not constant ..... But it is ... And thats the hard part ... Why ?
@manu1434u4 жыл бұрын
@Justa Fool what do you mean "proven"? Gravitational waves were proven to exist which were predicted by general relativity, atomic clocks are proving special relativity..should it be something tangible to be considered as proof..no one has seen an atom..but it's existence is proven by experiments.. should I say it doesnt exist because it cant be seen by a microscope or my eye..
@manu1434u4 жыл бұрын
@Justa Fool yes Einstein made mistakes..his assertion that universe is static by cosmological constant is false, but the idea that speed of light is absolute is true..been proven again and again..if light speed is absolute, spacetime should be variable and it's a theory..and it has been proven correct..see the article above..how do you refute it? Or do you have any other theory to explain it?
@manu1434u4 жыл бұрын
@Justa Fool why is it not rational when it's explaining all the things it was supposed to do so? Black holes, gravitational waves, light bending around massive object's, time dilation, length contraction..all are out of relativity..and are proven correct..what evidence DO you have to prove it false?
@manu1434u4 жыл бұрын
@Justa Fool Either way..Prove it wrong then! Thinking it is wrong doesnt make it wrong..PROVE IT WRONG if you think so. Relativity hasnt been proven wrong yet, so come back when that happens.. or stop making assumptions of your own with no backing.. How is LIGO fraud when after it detects gravitational waves and then they focus the telescopes towards that location, they are able to find electromagnetic radiation coming from those events as EMR might travel a bit slower due to gas and dust present in between. You have literally got no footing..
@TheAbominableChappal7 жыл бұрын
this is by far the best explanation on this topic I've ever seen.
@AnthonySiarkiewicz7 жыл бұрын
Just just love when Bobs arms go up cause he's train has been hit by lighting.
@Pepperball9097 жыл бұрын
So Robert Ford was nicknamed Bob in his younger years?
@WhiteBudWidows5 жыл бұрын
5:23 when my boyfriend thinks i was hitting on someone but i was just being nice
@Soulofyoga7 жыл бұрын
regarding 4:42: if the distance in the moving reference frame is shorter, it should take the light a shorter period to travel up and down (what you also mention at 4:10). Why is it longer than in the stationary reference frame (according to the formula)? If gamma was 2, then if 10 seconds pass in the stationary rf, 20seconds would have passed in the moving rf. Should it not be the other way around?
@blownspeakersss7 жыл бұрын
Why does Crash Course insist on making its videos so short? It seems like a topic like this could benefit from a 20 or so minute video. 9 really is not enough, in my opinion.
@Nothing_serious7 жыл бұрын
blownspeakersss Because Crash Course really means fast or short lesson or something like that.
@Mr8lacklp7 жыл бұрын
blownspeakersss because animations are a metric shitton of work
@blownspeakersss7 жыл бұрын
Well, a 20 minute discussion of Special Relativity would inevitably still be a "crash course." And I get that animations require a lot of work to make, but then they could just use more footage of the host talking or whatever with simple animations (showing equations and so forth).
@arstgkneio7 жыл бұрын
20 minutes is running kind of long. ideally, this wouldn't be your only source for studying this material.
@mohangrewal14667 жыл бұрын
Because people would be bored out of their mind if the video went on longer.
@jonathanblackwell427 жыл бұрын
Thank you so much for this episode. Even in my college physics classes, we never got into anything relativistic so I never really understood it. This was much needed. Great work, y'all!
@McHaven077 жыл бұрын
This has always bugged me, and it still does.
@EdwinLuciano7 жыл бұрын
My preschoolers are going to love this video. Thanks for posting it.
@elmothemilkman997 жыл бұрын
I think you guys made a mistake with labelling the formula at 4:38. Tv is the reference frame of a stationary observer, and To should be the moving reference
@crossfire14035 жыл бұрын
That formular just tells how long the same time-duration of stationary frame needs in the moving frame to pass from the view of stationary frame (clock-ticks). E.g.: T0=1sec, v=0,5c, how long do you have to wait/measure, to be sure that T0=1sec has also passed in the moving frame? ==> from perspective of stationary frame it takes a duration of approx. 1,15sec to pass on the stationary clock, to be sure that the T0=1sec-duration in the moving frame has passed. It's a little missleading, but the formular does not mean, that if in stationary frame 1sec has passed, that in the moving frame already 1,15sec have passed...
@crossfire14035 жыл бұрын
Otherwise: while in stationary frame 1sec has passed, you know at 0.5c of moving frame, that in the moving frame only 0.86sec have passed...
@srdanmilic49525 жыл бұрын
@@crossfire1403 And everything she said is based on ASSUMPTIONS and therefore I must ASSUME that everything she said is true. Sorry but my world is based on facts not assumptions.
@coldfinger459sub07 жыл бұрын
Over the past couple years I've heard this and seeing this explained many different ways but with your visual effects and a combination of your method of explaining I just had that " Ah ha !" moment. The lightbulb has just been switched on I completely see and understand now it's so simple. Keep up the good videos
@pinco_pallo6 жыл бұрын
Thank you very much! I'm an Italian student and I can't find videos like his in my Country. The graphic of these videos is superb and the explanations are excellent. Well done!
@Snidebark7 жыл бұрын
I came to this video with a competent understanding of the subject, yet found the video hard to follow. It all makes sense because it's all correct and well-scripted, but the editing and fast speech make it difficult to take in what she's explaining. The 'breathing time' between utterances is removed, and that time that it takes to inhale, although short, is just enough to allow us to process each piece of information before the next piece comes. Without it, all of this correct, well-scripted information is a rush of sound. No documentary maker or teacher talks this fast and without pauses between pieces of information, so why do it here?
@atfchannel34257 жыл бұрын
Snidebark مقزميزثز ي عرمربنتؤخعؤ😈😈😴😆
@bouguezinemohamed7676 жыл бұрын
Snidebark I don't know but I just paused the video every now and then
@MegaLotusEater5 жыл бұрын
You couldn't have had a competent understanding of the subject, as this vid is really clear and easy to understand. I had a limited understanding of the subject and understood it perfectly
@FknAzzMuncher5 жыл бұрын
@Irritable Jon Syndrome lol yeah socialism is relevant here
@nawra775 жыл бұрын
Pause and replay button: AM I A JOKE TO YOU?
@pytle7 жыл бұрын
I love listening to these while at work, and I keep thinking Symmetra is teaching me this inbetwen matches.
@Unassuming_Gay7 жыл бұрын
Ah, Finally the interesting stuff.
@oldcowbb7 жыл бұрын
classical is also interesting, but modern physics is indeed more interesting
@harry_page7 жыл бұрын
Tell me about it. Mostly boring old classical theories in physics at sixth form, and what little of quantum mechanics that's touched upon is left horrendously unexplained ;-;
@yssacnton955 жыл бұрын
Rigid body rotations is interesting, how rotational bodies can do wonderful stuff, gyroscope etc...
@gyurmarajzfilm5 жыл бұрын
You explained this better than my physics teacher. Also: You helped me solve my homework 💚 Thanks!
@stasacvetkovic64644 жыл бұрын
It is fascinating how you can understand so much and don't understand a word at the same time.. but you are incredible teacher ❤
@Jaydoggy5317 жыл бұрын
You described this in a way my brain could finally wrap around. Thanks.
@anjulichaudhary13257 жыл бұрын
who feels this did a better job than pbs space time??
@michaelsommers23567 жыл бұрын
Space Time hasn't covered special relativity.
@tahmidt7 жыл бұрын
They are catered for different audiences.
@bigdre90427 жыл бұрын
anjuli chaudhary for me VSauce is who usually makes me understand them
@isabellelindblad28356 жыл бұрын
Thank you! Im still confused but this is helping me dwell into the metaphysics of time.
@jeremymiller41897 жыл бұрын
This episode needs placed in your physics playlist.
@DaveGaming997 жыл бұрын
FINALLY! Only took 42 episodes to get to one of the most interesting parts of physics to me! :) Thank you!!!
@MusikCassette7 жыл бұрын
4:34 wait a minute, "stationary reference frame" "moving reference frame" ? I thought we established, that it is indistinguishable which one is moving. From the perspective of bob, the platform is moving. So from bobs perspective the time on the platform is dilated the same way. How can that be? That would mean that also t0=yt ( while still t=yt0) so t0=y²t. Something is wrong here. (I used y for /gamma to type it on a normal keybord)
@secondo927 жыл бұрын
It is indistinguishable because Bob sees the train station move past him. If he is not accelerating he would not be able to tell if it is himself moving or if the train station is moving(like when you're in the backseat of car next to another car moving at a constant speed, and the other car slowly decelerates, you can't tell if you're slowly speeding up or they are slowing down). So noone can actually prove who is moving unless one of them were to be accelerating, but then special relativity wouldn't hold. In Bobs' perspective he sees the world differently(everything has shrunk in size), but the train station sees Bob as if he shrunk in size. This gets more interesting once you investigate the twin paradox and that photons "experience" the world as if time had stopped entirely.
@MusikCassette7 жыл бұрын
I think you did not understand the question: bobs time is running slower that the stations time the stations time is running slower than bobs time ergo the stations time runs slower than the stations time ??? how does that work?
@secondo927 жыл бұрын
That is not the case. They perceive these things differently. Imagine that theres a clock on the train station and on the train where Bob is. Bob will see that clock is moving slower on the train station, while his own clock is running perfectly "normal". The train station sees that Bobs clock is running slower, while their own clock is running perfecly "normal".
@robertf78817 жыл бұрын
I am having the same problem. if t = yt0 where y is always positive then t > t0. According to the formula t = time in moving reference frame (clock in train) and t0= time at stationary reference frame (clock at train station) --> Then t>t0 means that more time will have elapsed on the moving train than at the stationary train station. In other words clocks are faster on the moving train... This cannot be true because the whole point is that clocks slow down as you approach the speed of light on a moving train. I suppose if you switched t and t0 like MusikCassette did then the formula would work out. Not sure if t and t0 are improperly labeled in the video or if I am misunderstanding the concept. Anyone help?
@MusikCassette7 жыл бұрын
Well, that does not help. you just repeaded the thought experiment, the question was a little more specific than that: Imagine the equation t=yt0 Imagine the equation t0=yt now Imagine the conclusion t=y²t and now Imagine me having a problem with that. The Problem is not, lack of imagination, but how to use those equations.
@doronbarzilay5904 жыл бұрын
Not stopping for even a second between sentences to give the viewer a moment to digest what you said while talking about one of the most complicated ideas in phisics is an excellent idea!
@NiknAknO4 жыл бұрын
If only there was a button to stop the video...
@doronbarzilay5904 жыл бұрын
@@NiknAknO a video that needs to be stopped every few seconds should not be an educational video.
@jamestaylor82176 ай бұрын
Best illustration of these concepts I've seen in 60 odd years. Thanks
@adamcampagnolo38967 жыл бұрын
Crash Course is my favorite thing on KZbin! Please fund this!
@Creamagination7 жыл бұрын
Love her British akcent, really good.
@yourfriendlyneighbourhoodh47007 жыл бұрын
Hidden driver no such thing as a British accent. What you're referring to is queen's English.
@afroman86267 жыл бұрын
What about Irish or Scottish, or Welsh? They're British too. I think that's what they may have been meaning.Cause I don't think she has an Irish accent
@Bugatti17 жыл бұрын
And this is why my major is computer science...
@IceMetalPunk7 жыл бұрын
I'm also a computer scientist, but I've always loved special relativity :)
@oldcowbb7 жыл бұрын
what if you have to programme a satellite
@IceMetalPunk7 жыл бұрын
+oldcowbb Then he'll use a relativity library to handle that part of the math :P
@theindianremix94045 жыл бұрын
I have to take this course for comp sci :(
@dphorgan5 жыл бұрын
Quantum computing?....
@benjaminazmon7 жыл бұрын
I love that spacetime is the 42nd episode. now we know the meaning of life the universe and everything
@sajadkhosravanis.82889 ай бұрын
Thank you so much for your ideal development of every aspect of the tutorial.
@Not_here12344 жыл бұрын
I'm sending this to my friends to mess with their heads :/
@nah77494 жыл бұрын
Brianna Amador huh, I’m sure you’ll stump em, I’m confused out of my mind! 🤣
@GeorgeCopperfield7 жыл бұрын
She's so cute !
@substitoad70697 жыл бұрын
Torin Webster cute
@rolandomarinhdez82626 жыл бұрын
Torin Webster she is...
@torpezaincreible86926 жыл бұрын
ikr😍😍😍😍😍😍❤️❤️❤️❤️❤️
@ashboon16257 жыл бұрын
Please do nuclear, atomic and quantum physics next!
@j-theorythequantummechanic60257 жыл бұрын
ash boon I think general relativity is next right? If they're going in order.. Then quantum mechanics..
@braddboy57 жыл бұрын
I don't understand the statement about simultaneity. I get that bob observes the lighting at two separate moments and the person on the platform sees the lightning at the same time. But that doesn't mean its isnt a simultaneous event. Since the person on the platform is equidistant from both bolts of lightning and the speed of light is constant, it happens at the same time. For bob the distance and time are different for each bolt. This doesn't mean that it wasn't a simultaneous event. If someone claps their hands right next to me and someone else does the same but further away and i observe the sound from the closer clap first it doesnt mean that the claps didnt happen simultaneously. This means that even though bob sees the lightning that is closer first, both bolts still strike simultaneously.
@p3nf9ld5 жыл бұрын
Everything depends on the frame of reference. Simultaneity can only be judged from the single reference point. That is, you observed the claps occurring at different times so not simultaneous to you. At least one of the people clapping heard non simultaneous claps. However, one of the clappers may have heard the claps at the same time so he correctly assessed them to be simultaneous to him. There is no such thing as describing an event as irrefutably simultaneous.
@harshgoyal70987 жыл бұрын
Hi Crash course team, at 4:38 she says that time in that moving reference frame = time in your reference frame * gamma, plz check it again because I feel there is some error in that equation. it should have been like: time in your reference frame = time in that moving reference frame * gamma
@ronblaess16 жыл бұрын
No, they are actually right. Time is dilated in the moving frame, so you have to multiply the time in your frame by gamma.
@Spartanruler7295 жыл бұрын
Raumzeit - Vlog der Zukunft time moves slower as you approach the speed of light
@crossfire14035 жыл бұрын
That formular just tells how long the same time-duration of stationary frame needs in the moving frame to pass from the view of stationary frame (clock-ticks). E.g.: T0=1sec, v=0,5c, how long do you have to wait/measure, to be sure that T0=1sec has also passed in the moving frame? ==> from perspective of stationary frame it takes a duration of approx. 1,15sec to pass on the stationary clock, to be sure that the T0=1sec-duration in the moving frame has passed. It's a little missleading, but the formular does not mean, that if in stationary frame 1sec has passed, that in the moving frame already 1,15sec have passed...
@crossfire14035 жыл бұрын
Otherwise: while in stationary frame 1sec has passed, you know at 0.5c of moving frame, that in the moving frame only 0.86sec have passed...
@TheRealFOSFOR7 жыл бұрын
They always talk about how things depends on the point of view. Everything is relative. Or something... But if I fly a rocket at the speed of light. Why is time slowing down for me? Why not the rest of the universe? Who chooses witch one of us is moving. Me in my rocket or everything around my rocket? I specifically remember reading somewhere that it is impossible to ever measure the absolute speed for anything because you don't have any reference point.
@alexneff35126 жыл бұрын
You can only measure things through what is called an inertial reference frame, or non accelerating point of view. If this is true, you can measure the other things acceleration, telling you that it moved, not you. This is actually the exact scenario that led Einstein to create general relativity, which takes acceleration into account
@ahmaquindi7 жыл бұрын
This video came out right when I needed. In a couple of hours my physics teacher is going to give a lecture on this and I'm so exciteddd physics is the best
@maksphoto787 жыл бұрын
I kinda had an epiphany myself about how the speed of light (in vacuum) remains constant no matter what. Speed is distance divided by time. The speed of light remains constant through the stretching of time (making the taveller's local time slow down).
@antoniobaker38287 жыл бұрын
I was so ready to pay attention and try to understand this then instantly got distracted on how beautiful she is
@kcwidman7 жыл бұрын
If I am in a spaceship flying to alpha Centauri, would the 4.1 light years I need to travel contract if I move at a significant fraction of C? So I would actually travel less distance on my way there from my perspective?
@DaveGaming997 жыл бұрын
The distance is always the same; the distance never changes, it is only the amount of time that you experience while traveling that distance at a certain speed.
@kcwidman7 жыл бұрын
Everyone experiences their OWN time to be normal. So if I were watching someone in a spaceship at 99% c I would see their clock tick slower. Since the people IN the ship are experiencing time normally, doesn't that mean that from their perspective they don't travel the distance they calculated at the start of the trip?
@secondo927 жыл бұрын
If someone was to be moving at 99% of the speed of light, the distance between the earth and alpha Centauri would be length contracted so much that it would seem only a foot length away in their frame of reference.
@kcwidman7 жыл бұрын
secondo92 but the thing is, it doesn't seem like it is 1 foot away. From the perspective of the spaceship, it is objectively, 100%, the actual distance, 1 foot away.
@secondo927 жыл бұрын
Yes to correct myself, it is 1 foot away. It's all about how you perceive things. That's why it is called relativity.
@samdaniel95957 жыл бұрын
From Hist to Philo. From Econ to Poli Sci. Now with theoretical physics!!! You guys are the best!
@masterhidsert10437 жыл бұрын
Cool! I'm more of a chemist but physics is phenomenal
@Oliver-fu1go7 жыл бұрын
AHHHHHHHHHHHHHHHHHHHHHHHH! Interesting... brain dead... but interesting
@pietrocelano237 жыл бұрын
watch the "would headlight work at lightspeed?" video by vsauce
@torpezaincreible86926 жыл бұрын
that's so relatable hehe😂😂😂😂😂😂😂
@zes38135 жыл бұрын
wrg
@netahamiel43044 жыл бұрын
we just gonna forget about how mass increases as you get close to the speed of light? fine
@science-y92094 жыл бұрын
Mass increases? ??
@daena92894 жыл бұрын
Yes, because according to Einstein’s famous equation, E=mc^2. (Where E is energy, m is mass, and c is the speed of light.) Because of the equivalence of energy and mass, the more energy an object has due to its motion would add up to the mass. (Therefore, as the energy required for motion increases, so does mass.) And that is why mass would increase as you approach the speed of light.
@eliirrii4 жыл бұрын
This is actually considered to be incorrect now. According to the OpenStax text book (Volume three, section 5.8), it says under relativistic momentum: "The relativistically correct definition of momentum as p=γmu is sometimes taken to imply that mass varies with velocity: mvar=γm, particularly in older textbooks. However, note that m is the mass of the object as measured by a person at rest relative to the object. Thus, m is defined to be the rest mass, which could be measured at rest, perhaps using gravity. When a mass is moving relative to an observer, the only way that its mass can be determined is through collisions or other means involving momentum. Because the mass of a moving object cannot be determined independently of momentum, the only meaningful mass is rest mass. Therefore, when we use the term 'mass,' assume it to be identical to 'rest mass.' "
@talalzero14184 жыл бұрын
I’ve watched 10s of videos explaining/mentioning time dialation and this video was the only one my brain was able to digest. Thank you
@littlepix1017 жыл бұрын
You guys might have saved my life. I'm in the middle of my first exam period of my degree (biomedical engineering), I failed my first physics exam- and need to retake it, on Tuesday. I have seen the two theorems for the time/length thing, and was never sure which was for the stationary system... Your explanations were very clear and helped my understand why I kept getting these questions wrong... I think I love you
@cuzco087 жыл бұрын
Explained as beautifully as she is.
@j-theorythequantummechanic60257 жыл бұрын
Marcus Taylor She's mine!
@pet35907 жыл бұрын
I don't think I need to start saving for retirement, I'm still in school.
@pet35907 жыл бұрын
I like this series but please don't advertise insurance companies, do charities or something education related like the great courses
@skrenos7 жыл бұрын
First off, it's never too early to start saving for retirement. Second, content creators don't always get to choose who sponsors them. If it's a choice between an insurance company and no sponsorship, you bet your sweet bippy they'll pick the insurance company.
@ajeuscher79887 жыл бұрын
somebodys gotta pay the bills right? At least its at the end and doesnt impact the rest of the episode at all
@marrs10137 жыл бұрын
Sameopet I guess it depends on who is actually willing to pay for the slot. Just becouse you are not paying for it, it doesn't mean it's free. But I'm sure there are ways to support the show...
@marrs10137 жыл бұрын
Sameopet By the way, the later you start to save the harder it gets, as you need to put aside more and more to make an actual difference by the time you retire. So do yourself a favoure, and start saving the first day you start to work. You can't imagine how happy and grateful you will be later. This should be part of curriculum, so in a sense it IS educational.
@kattyseraphin38125 жыл бұрын
Shouldn't time and distance be directly proportional? I mean if "v*t=d" when time increases, the distance should also increase right? Why is it inversely proportional now? Can someone please explain
@LudusYT5 жыл бұрын
Ann-K Seraphin - I cover this in chapter 2 of my special relativity series. Feel free to take a look if you want a more in-depth understanding of SR. Here's the short version to hopefully clear things up for you. If you stand still and measure the speed of a light pulse, you would get the speed of light "c". Let's now say that another observer is moving in the direction of that light pulse , at a velocity v, and also measuring it's speed. Intuitively, you would assume that they measure the speed of the pulse to be c-v relative to them. The problem is that, in reality, they also measure the speed of light to be moving at c. So how do you account for this? Since v=d/t, you could accuse them of measuring either distance or time incorrectly. In order for them to increase the velocity from c-v to c, they must have either measured a longer distance or a shorter time... or maybe both. In my chapter 2 video, we find out that the answer is both, and that is the roots of length contraction and time dilation. I hope this helped! Let me know if you are still confused.
@shehryarzia96614 жыл бұрын
Time dilation is just like our teacher lecture. For us it is of 45 minutes but for him it is only 5 minutes.
@Robert-qw9hp7 жыл бұрын
6:33 "Time goes faster for you than for Bob", but later less time passes for you than for Bob, what??
@TheRandomEnthusiast7 жыл бұрын
Robert Vincent Struggling with the exact same thing here!
@alexneff35126 жыл бұрын
Allen Dowe I thought the same thing. Not completely sure but I think the logic in relating time dilation to length contraction is flawed, or at least i don’t understand it. How can you maintain that the stationary perspective measured longer in the time dilation example, if in the length contraction example you say that in d = v * t, the moving observer measures longer?
@extizt66776 жыл бұрын
If time is passing faster for you than bob then the same event should take less time to occur for you while it takes more time for bob
@hartog23326 жыл бұрын
then if you take this scenario to like a year long journey Bob would have aged more than you? as it seems more time has passed for him so he would have thus aged more?? This is not the standard answer to the scenario, where fast movement= less fast ageing.
@MalakTumeh5 жыл бұрын
Hello Robert, I've taken time to calculate this, and the video is, indeed, wrong. If 667 nanoseconds pass for Bob, 770 nanoseconds should have passed for the still reference frame. I believe they have made a mistake when defining t and t0. It should be as followed: t= Time for still reference frame t0= time for moving reference frame
@abrahamlincoln98696 жыл бұрын
I'm in love with her..
@RockRita094 жыл бұрын
Right! Smart and pretty!
@audreykea77714 жыл бұрын
@@RockRita09 yea well im in love with barack obama
@katerinavachova62176 жыл бұрын
My brain is crying but I’m loving it
@cough54316 жыл бұрын
i’d just like to point out the irony in that last comment... “that’s because we’re used to seeing the world at much much slower speeds than light” 😂😂😂 great vid btw
@bianca-jj4mc4 жыл бұрын
i did not understand fiskskxkd
@jadonbertholf5477 жыл бұрын
My brain hurts
@IceMetalPunk7 жыл бұрын
The short and simple version: you know distance = speed x time, yes? And you know that in a right triangle, the hypotenuse length C is longer than the base length B, right? So if light travels the same speed in a vacuum no matter what (which it does), then if someone shines a light as they're moving past you, they'll only see the light form a straight baseline, while you'll see it trace out the hypotenuse of a triangle. So if speed is constant and the distance is longer, then time must be changing between you and them--specifically, since you see the light moving a longer distance, it'll seem like their time is slower than yours (since it takes longer to travel). Similarly, if the time something takes to pass you is longer, but it's moving at the same speed for both of you, then it will seem to that object that it's longer than it seems to you--which means from your perspective, it's "shrunk" or contracted.
@o.p.rajput6555 жыл бұрын
@@IceMetalPunk dude. Cheers for the effort
@nimrod96407 жыл бұрын
You are becoming a famous yt channel, and I think that a lot of people from different nationalities are watching you interesting videos. So it could be realy amazing if you give us some french, spanish, german, or italian subtitles. Thanks for reading !
@tiborcongo6 жыл бұрын
awesome, ads suck, but this is our world so if it's what it takes to get this content out, I'm in! What's killing me though is the Hafele-Keating experiment, cannot get past the paradox of the clocks not having the same change relative to each other (I'll keep reading)
@310iq67 жыл бұрын
Brain.exe has stopped responding.
@alexneff35126 жыл бұрын
Not completely sure but I think the logic in relating time dilation to length contraction is flawed, or at least i don’t understand it. How can you maintain that the stationary perspective measured longer in the time dilation example, if in the length contraction example you say that in d = v * t, the moving observer measures longer? Time should be longer for the stationary perspective, hence the twins paradox, so how is the distance for stationary measured shorter if d = v * t? That would imply that the time multiplier is shorter, but it’s not. An solution to my confusion would be greatly appreciated
@alexneff35126 жыл бұрын
Also this video gets the lack of simultaneity wrong. That example simply demonstrates light being the fastest means of communication. With telescopes, we can see the early universe because the light has taken that long to reach us, but we still know it happened billions of years ago; it is not out present, we are just seeing it now.
@davezimmer90536 жыл бұрын
Yeah I was also confused by that.... I tried to put that calculation into the equation but couldn't get that right.
@ronblaess16 жыл бұрын
What she failed to mention is that the clocks used for measuring the time it takes the train to pass are BOTH with the stationary observer. Bob sees a certain time pass on a clock at the train station (he concludes that his train is 100 meters long) yet Sarah? measures less time on the same clock as for her Bob's train is length contracted. That really was an oversight in an otherwise pretty good video.
@crossfire14035 жыл бұрын
@@ronblaess1 but why does the "moving-frame-observer" measure its own "plattform-pass-by-duration" by using a relative to him moving clock? This outer clock-readout therefore will result in a wrong "time-duration-measurement", because the outer clock is in a different reference-frame from the perspective of the "moving-frame-observer". How can it be right to make time-measurement by using an "outside-the-own-referene-system-clock"?
@chickenbro80867 жыл бұрын
would this mean when we run this happens? and does your math consider how fast we blink to capture light?
@SSGranor7 жыл бұрын
Sure, it happens when you run; but, the gamma factor in that case is about 1.0000000000000002. And, blinking is irrelevant. All these effects are measurable with instruments that have no need to blink.
@KevlarSammy9 ай бұрын
PBS was there when I was a kid and is still there when I’m an adult.
@thomasrivera86267 жыл бұрын
She is Beautiful and I like her but what happened to John Green?
@recklessroges7 жыл бұрын
I don't think Physics is John's strong suit. He does books n' stuff. Hank could probably do Physics, but I really like Dr Shini Somara
@thomasrivera86267 жыл бұрын
LOL Ohh thanks.
@kudos42017 жыл бұрын
id' rather have someone who has a doctorate in physics to explain. even if it is scripted.
@NateManPro7 жыл бұрын
First ha ha what a meme
@Nana-kw2qo4 жыл бұрын
Correct me if I’m wrong but special relativity is when time warps to accommodate the speed of light since usually we live at a rate slower than the speed of light