Why can't you reach speed of light? (Intuitive explanation using time dilation)

Part 2 (Ship's perspective) - • Why can't you still re...
An intuitive explanation for why objects can never react the speed of light?
Chapters:
00:00 Introduction
00:10 The common "explanation" (Infinite energy)
00:37 Photon clock & time dilation
02:22 Do real clocks undergo time dilation?
03:59 Evidence for clocks slowing down (Atomic clocks)
04:39 Evidence for TIME slowing down (Muon Decay)
07:52 Deriving time dilation equation (Intuitively)
09:24 Summary of time dilation equation (The Lorentz factor & proper time)
10:40 Some values for the Lorentz factor
11:40 Why can't you reach speed of light?
14:11 Why it REALLY takes infinite energy?

[@Mahesh_Shenoy]

I heard you folks! What do we see from the ship’s perspective? Here you go - kzbin.info/www/bejne/bKi7qJmZe75-gqc Hint: We discover the second consequence of special relativity. (one more to go)

[@-_Nuke_-]

Yeah, this explanation that you give requires the establishment of an absolute reference frame. If we can do that, then time dilation and length contraction are real phenomena. Otherwise, if we can't define an absolute reference frame, and spacetime really is absolutely relative - then time dilation and length contraction are NOT real phenomena, but simply visual illusions like the ones we get when we put a spoon inside a glass of water... The spoon doesn't change shape... So yes, a lot can be said about this, and honestly, I don't think that a full explanation really exist. Not even Einstein was sure what to make of all that. As for someone who has read his actual books, along his life, he was constantly changing his mind about if an absolute reference frame really exists or not...

[@jonasnangolo-sc5wi]

I like this guys explaination it is superb. God bless you bro thank you .

[@timhartherz5652]

I guess you won't notice the dilation from inside the ship, since it affects you as well, ship keeps accelerating at a constant rate, getting you to Lightspeed eventually. But you might arrive a couple of million years late at your destination. Ooops

[@-_Nuke_-]

@Mahesh_Shenoy I think that you are trying to say that the speed of an object is an inherent attribute of that object - and its not. For example, a neutrino - ISNT traveling close to the speed of light. Its only traveling close to the speed of light RELATIVE to us here on Earth. There should exist, at least 1 observer out in the Universe that measures the speed of that same neutrino and finds it to be equal to that of a bike... So what is it? Is the neutrino traveling close to the speed of light or the speed of a bike? Neither. The ONLY way to know the speed of a neutrino is if we had a global refference frame, which is absolute, and then yes - then we would be able to assign "close to lightspeed" as an inherent ATTRIBUTE to that netutrino. We will know for sure its exact speed relative to that 1 absolute frame. So to ask "Why can't something travel at the speed of light" is a question that implies - that we can somehow measure the exact speed of an object... Which in turn implies that there is a global refference frame that will give us that knowledge. Neither of these are shown to be true; The speed of light being a speed limit CANT be explained using relativity - because its an AXIOM of relativity.

[@invisalats841]

Well, it's fine, but it's basically theoretical. We currently have a very surface level understanding of the universe and its physics. We know the results but not really the underlying structure that determines the results. It's like understanding a car's functions, what it can and can't do, but having no knowledge of the engine, drive train, suspension, cooling. You only see the results and don't actually understand how the car works. So you keep pushing to see if the car can, in fact, do things it's not supposed to be able to and accept the results even though your lack of understanding of the components that make up the car could be the reason you are getting the results and not that your results are definitive.

[@longnamesaredumb]

I’ve watched several MIT and Harvard lectures on special relativity and this is the clearest explanation of time dilation I’ve ever seen.

[@9028abhishek]

Because it's wrong to make it simple... Start from a equation and say that it's not intuitive and then arrive at same equation and accept that to be intuitive...

[@wingstrongwingstrong]

it's explained an obvious simple thing at a first grade level. And the obvious questions it should raise, no one discusses or answers

[@vishnupeketi7596]

​@@9028abhishekTbh this YT video is falsely titled. Instead of can't reach the speed of light it should have been not able to observe an object reach the speed of light. The cornerstone of this video is that which can't be observed or measured is not science, hence not possible.

[@wizarddoge4272]

@@vishnupeketi7596 yea that confused me as well, it's all about observing an object approaching the speed of light, but what about if you were on the spaceship itself?

[@billant2]

Well, in the beginning he mentioned that a common answer is that mass and consequently the energy required to accelerate a ship closer to the speed of light increases infinitely. And that's actually true, he just gave a more detailed explanation of why it's happening due to time dialation (transferring photons/energy from one atom to another more slowly).

[@Rosetulippp]

Who want Mahesh to infinitely keep making videos?

[@misterlau5246]

🥺 No way, that's too long, poor Mahe🥺

[@user-me7jb8dz3j]

✋️

[@brilanto]

That would need infinite time and/or energy...

[@sumibordoloi2000]

So easily explained....plz make such videos

[@lukecanavarro]

🖐🏼

[@jjones503]

2 AP classes in high-school, and 4 years of high level mathematics in college, but the random guy I find on youtube explains this better than any teacher or professor I've ever had.

[@Famous_Mist]

Uau... That school was really bad.

[@wyattmurphy7153]

It’s all in the accent jjones503.

[@manan-543]

Let's be real. You never paid attention in school. U just wanted to get thru the exams. Even if u had a good teacher wouldn't care

[@jjones503]

@@manan-543 I tried to pay attention, but got tired of paying someone to tell me which page to read just for a piece of paper.

[@chiragarjun3270]

@@manan-543 yes never blame teachers, first of all today education is business

[@kenpaget2895]

this guy is THE BEST, MOST CLEAR EXPLAINER, after 50 years of attending lecttures, reading hundreds of books. the guy has a gift... thank you so much

[@TechnooRam]

You have no idea how good you are at explaining stuff. Genius!

[@Mahesh_Shenoy]

Super glad that you think so!!!!

[@ReneSookdeo]

Yes I agree he did an amazing job

[@itzakehrenberg3449]

Hi Mahesh!! Can you make a video about Cherenkov radiation? Why does a charged particle emit electromagnetic radiation when it is traveling through a medium at a speed greater than that of light through the medium? @@Mahesh_Shenoy

[@karllev8763]

Massive thanks for this video, I haven't heard anyone explain this as good as you before!

[@ChineduOpara]

He blew my mind

[@mehrdadhassanabadi3391]

After 38 years finally someone came along to explain this phenomenon in an intuitive and understandable way. Thank you for finally making me understand what is going on! 🙏

[@Zach-mi6to]

Well one thing always ruins the logic. He said the clocks time is affected when in motion. Motion however is relative, so you, observing the clock, are also moving sideways relative to the clock. So how does the universe decide which time frame slows in relation to the other? They cant both slow down.

[@BooleanDisorder]

​​@@Zach-mi6tobecause there is no universal frame of reference. This is all relative to something, a clock at rest compared to the moving object (relative to the resting clock). There is no universal frame or clock. Everything is relative to whatever resting object you measure from. In essence: you need to unthink the universal frame of the universe that feels intuitive. It doesn't exist.

[@Zach-mi6to]

@@BooleanDisorder u r missing your own point. There's no such thing as a "resting" reference point. There is no resting clock, bc as u mention, there's no universal reference. That's my point.

[@Zach-mi6to]

@@BooleanDisorder with acceleration yes, it then becomes an asymmetrical equation and dilates time just like a gravitational field. But two objects in uniform relative motion, for both to experience a slowing of time would suggest they are each creating a new version of reality. Or something like that. Doesn't make sense but maybe there's a consensus answer somewhere.

[@duxxxhm]

It is not a phenomenon it is a theory.

[@codelinx]

Why isn't your channel way more popular!? Holy crap. I literally understood everything... 🤯🤯 your video also clarified a lot of things "explained" by other videos and other people and other writings.

[@JohariW]

I've known about this since high school 20+ years ago, but this is actually the first time I've ever understood why. Thank you so much, you have truly enlightened me, and everything finally makes sense.

[@Major.Tom.1973]

😮 You taught me in 16 minutes something I wasn't able to understand after years of self-study! 👏👏👏🙌🙏

[@DanniDuck]

You might want to learn something a little easier if it took you years to not learn something.

[@Pommes736]

Don't worry you still haven't learned anything

[@99Gara99]

You still don't understand, you just think you do

[@helifynoe6956]

Sorry to hear that man. I dropped out of school due to the side effects of a nasty head injury that also left a ceramic plate on the left side of my head. But despite teachers thinking that I was just one step away from being labeled as "Mentally Challenged", I still managed to independently discover the special relativity(SR) phenomena, derive the SR mathematical equations, along with independently deriving the Lorentz transformation equations, and the method that I used to derive these equations has not even been thought of by others as of yet.

[@andyjones7121]

This thread cracks me up. A self deprecating post by a confident person and a bunch of low self esteem jackasses piling on. "Sorry you not smart. Me understand everything because ceramic brain." It's pretty hilarious to me.

[@Poodleballin]

Wow. I have read countless Quora posts/comments, watched many YT vids, read science mags, articles, etc. and this FINALLY explained it to me. Only took like 40 years! Thanks so much for what you do.

[@Mahesh_Shenoy]

Wow, thank you :)

[@czyprodigy2743]

It’s amazing how concisely you can explain things that took us thousands of years to figure out. Thank you

[@mojojo_san]

Finance and Data Analytics guy here, passionate about math and astrophysics just got the most clearest explanation of why we can't reach speed of light on a random Saturday at 2 AM. Thanks for dumbing it down for us, and your enthusiasm !!! You just gain a subscriber.

[@MouadhCosmic93]

Everybody who makes physics videos talk about time dilation and special relativity.. but no one explained it as intuitively and as simply as you did, I have stumbled upon time dilation equation many times and never seemed to understand where it came from... But now I can perfectly see it and make sense of it, keep up this beautiful work and I am deeply grateful for your efforts

[@johndow8725]

Agreed. Best layman’s terms breakdown while still utilizing the actual science involved.

[@chrisking6695]

I believe that’s because they don’t understand it either. They just regurgitate information. If one can break down information to an intuitive level then one has truly understood it.

[@jayuppercase3398]

Just remember there are 1000s of videos explaining why the earth is flat and the moon doesnt exist

[@Scritley]

With no exaggeration, this man and his videos should be in every high school and college classroom. I've struggled with this topic for years and in two 15-20 minute videos, he clearly and concisely explains time and distance dilation in a way that someone like me, with a great interest in astronomy/physics/special relativity but who does not possess a degree in these areas, can understand. Furthermore, the way he unfolds the narrative, like a building conversation with Einstein and with his contagious excitement of the topic and of finally understanding it sprinkled in, completely amplifies the greatness here. Well done! You've earned a life-long subscriber.

[@royfeigel2535]

If you think what he says makes sense you are still struggling

[@firstnamelastname4749]

​@@royfeigel2535 What this video does is explain time dilation in a way that can be easily understood. I now grasp the concept. I do not understand it, but If I were to learn the details I would be able to link the equations with my understanding of the concept to fully grasp it

[@ksalarang]

same!

[@sanjeev.101]

ahh! For years, now I have gotten the video which almost explains me why can't we reach the speed of light. Great one. And the best part is you are more excited to explain it.

[@martincostaaa32]

“The mewing twin will age slower”

[@stevenweller9413]

I’m 52 and have a college degree (granted in history) and am also a big sci fi guy. This is the first explanation I’ve heard that actually made sense, even in physics classes. Thank you.

[@redbean9410]

so essentially you don't have a college degree

[@teacher_fher]

​@redbean9410 ???? You do understand that history as a field of human knowledge is older than any natural science, right?

[@redbean9410]

@@teacher_fher lmao okay and? a history degree isn't gonna get you anything, except maybe a job as a history professor lmao

[@STho205]

Despite the rude jabs here..."Oh the Humanities!"....your statement is very common in our population. Many people highly educated or stopping at HS are highly specialized in education today. There are far fewer hard sciences students than non empirical students in most of society. However there are a great number of Sci Fi fans that have picked up science sounding terms but applied by fantasy writers as a vague technobabble. I (physical chemist) run into a lot of people that insist they understand and are experts on some material theory or another (astrophysics, medicine, chemistry, biology, geology, etc...). Yet in casual conversation I can often find out exactly where they picked up the idea. I'm sure you find the same is true when you meet someone that learned history at the box office. History is a fine and honorable degree and profession.

[@redbean9410]

@@STho205 there’s less hard science students because it’s not for everyone. Most people can’t obtain the degrees for those jobs

[@AdityaPatwardhanJ]

You, sir, are a gift to physics students everywhere!

[@chrisbarter7627]

I've been reading and discussing Sagan's "Cosmos" with my 9yo daughter for a little while, and I just found this video right around when we were talking about time dilation as it appears in the book. I just wanted to say that the video is great and you do wonderful work. I really appreciate your channel, as does my kiddo. Keep up the good work!

[@thomasdarscheid3665]

Just incredible. You have the very rare talent to explain these very complex issue to non physicists so they are actually getting it, only by use of a few graphs and your unique way of breaking the basics down. Never seen anything like this before. Greatest respect to you. And a huge THANKS.

[@Cryptic808]

My man. This was one of the most joyous videos I’ve ever watched on physics. Your joy is contagious and I love every second of it. Love the way you explain everything and your emotion behind it all.

[@derpataur1162]

It never once occurred to me, that because the speed of light is constant, when an object is moving it effectively means that light has to travel more distance... but it's not going any faster to compensate... and that is literally what time dilation spawns from. I love that. Thanks man.

[@seawaterjohnmiller7118]

speed of light is infinite

[@emerson3539]

@@seawaterjohnmiller7118huh

[@donaldslayer]

@@seawaterjohnmiller7118the slow mo guys disproved this

[@seawaterjohnmiller7118]

@@donaldslayer where? how do you test light in another universe when ur in this universe? can't be proven here.... light is a wave, it is slowed down when travelling through a medium, the vacuum of space is not empty..... ever heard of dark matter ? maybe that is what gives light its constant speed.... derrrr

[@darkracer1252]

@@donaldslayer the slomo guys only proved that light moving through a medium has a slower speed. (if you don't understand the subject it's generally a good idea to shut up untill you do understand it) light basicly has infinate speed. but only from it's own perspective. from our outside perspective there is still the speed of causality to take into account. the speed of information. if you were a light particle. a photon. you would basicly die as soon as you are born. not even any time to experiance anything. from the exact moment you are emitted. you smack into whatever surface you are shining on. doesn't matter if this is a flashlight shining at a wall. or the light of a star billions of lightyears away reaching your eye. it's in the same exact instant. from the outside looking in however. you move at nearly 300k kilometers per second. 299.792.458 km/s or almost 190k miles per second. 186.000 miles/sec and it's always that speed. no matter how fast you are moving. and no matter in what direction you are travelling. the only thing that can slow light down is it moving through something. like air. or a gel. or whatever. and that's how they slow light down enoegh that you can capture the propegation of reflections move through something with a camera. it's physicly impossible to make a camera fast enoegh to capture the speed of light in a vacuum. because it would take infinate energy.

[@lotmyle5465]

This is probably the best simplified version which doesn't dumb it down so much as to strip the actual meaning. It information a layman is able to actually 'get' which was previously only acknowledged and understood as factual, but too big to truly 'put their thumb on' without occasionally pondering what exceptions could apply.

[@Braeden.F]

This is actually the best explanation I have ever and will ever hear about this topic ever. And I've watched probably hundreds of videos on this sorta thing over the course of several years. Well done 👏

[@GG-lp2ex]

This was the best explanation ever. You’ve asked the same questions I had, a real clock and now I understand why we simplify it. Thank you for this in depth answer. My physics professor just keeps saying well you can’t travel at the speed of light, you just can’t, doesn’t provide an answer. Now finally I understand why time dilation matters. ❤

[@AlbertTheGamer-gk7sn]

And because of time dilation combined with dividing by 0 to unleash the power of quantum effects, the light barrier can be broken, all we need is to make such machine that can divide by 0, a computer high-tech enough to program such machine, and fuel potent enough to allow the machine to use quantum effects. As long as we break away, everything becomes possible.

[@markiv2942]

@@AlbertTheGamer-gk7snThis is utter nonsense.

[@pythondrink]

Yes lmao ​@@markiv2942

[@MertKaanAkdag]

This video doesn't just explain why we can't reach speed of light. It explains much more than that. For example, it explains why time slows down when you move very fast, but the moment I felt like I was enlightened by this video was when I realized that this can also explain something that I never understood before. I am talking about how the concept of relative speed doesn't apply to light and we always see the light moving at light speed regardless of our own speed. I still don't understand it fully but I feel like this video gave me a big hint about why that's happening.

[@huskypup3489]

I find it useful to consider that ALL objects move at the same speed through spacetime at the rate of c. A stationary object is moving only through time and a photon is moving only through space. Other objects move at different ratios of space vs. time depending on their speed, but an object's speed through spacetime never changes.

[@Noblp]

So basically two photons are emitted from one source - a lightbulb on a moving spaceship. One hits the eye of a traveler onboard, the other hits yours (and you are outside the ship and at rest in space. Wearing a spacesuit, of course, cause you’re smart). Two possibilities exist: 1. The ship moves away from you. 2. Or towards. In first case photon “forced” to “move” more distance towards yourself than it would’ve if the ship was at rest same as you, in second vice versa. But! And it’s a big fundamental physic’s BUT(t) 😉 Photons always travel at the speed of light at all reference systems, no mater what, so it will reach both of you and the traveler all the same, however it travels as a wave not as particle. And since distance was increased or decreased wave gets “stretched” or “compressed” in spacetime, which means it will have lower frequency in first case and higher in second. So for the traveler it would be ordinary light - nothing’s changed, but for you it would be red-shifted or blue-shifted accordingly. To visualise it: imagine photon as a particle skipping on a bridge. The bridge represents the distance between point of emission(in our case lightbulb) and your eye. At rest everything is simple: photon happily skipped on the bridge towards you at the speed of light and smiles meeting you (because you have inquisitive mind and want to understand him) Now imagine the point of emission goes away from you. Photon looks at the bridge sighs quietly and starts it’s journey at the speed of light as usual. However every jump, the bridge gets stretched a little bit underneath him. So even though our little but very determined photon jumps as high as he can and travels at the same speed of light, he lands a little bit farther away from you and from where he should’ve landed if damn bridge just kept still. But it’s keeps stretching and stretching… Every single jump (how exhausting!) So no matter from what perspective we look at him now we still know it’s a photon because he jumps a photon high and travels at the speed of light. But remember he’s very determined to meet you(for reasons stated previously)! So finally he will reach you, tired and red from exhaustion (poor little fellow is completely red-shifted! now it’s easier to remember which way is which, right?), but of course the distance he traveled was bigger and because we know speed was the same, it means it took more time (v=d/t). In the other case bridge unexpectedly starting to shorten every time he jumps and although he’s very happy about meeting you sooner it’s still freaks him up a little bit too. So he jumps as high as photons should, but his jumps are just shorter this time because the part of the bridge he planed to jump over is became shorter instead (what a world! What a strange world we are all existing in! He probably thinks. Well of course. He doesn’t understand speed - he is born to know only one and never can accelerate or slow down). Nonetheless he reaches you very excited because it took so less time to get to you! He happily bounces around you, but unfortunately you can’t see him he was jumping so closely so short distance he accidentally blue-shifted into blue then violet, ultraviolet and finally into microwave range. But don’t worry science got you both covered. You can still meet with the help of radio-telescope. It will greet photon with it’s antennae and translates him into visible spectrum for you. Happy end. Hope it helps. It’s overly simplified, but at the core is correct. Just remember photons do not (under usual circumstances) propagate as particle in reality. The cake is a lie…. I mean the bridge! 😅 In this visualisation the bridge represents spacetime for the wave to propagate in and the photon represents every other characteristics of light (electromagnetic force). To understand it further we have to dive into wave functions and quantum theory which is beyond the scope of this explanation. Keep asking questions, reading science literature and watching educational videos. See you on the other side of electromagnetic spectrum!

[@Noblp]

@@huskypup3489​​⁠I’m so sorry to shatter your understanding, but you’re wrong and Einstein is right. It’s all about reference frame. Objects do travel through spacetime at different speeds depending on point of reference, same as force carrier particles such as photon, we don’t know does the time goes “forward” “for them” or “standing still” or something else entirely, however the can observe and measure their speed, which is constant in any frame of reference, and means they do indeed travel in spacetime. Basically bosons except for mesons are incapable of slowing down beyond light speed in any reference frame, while aforementioned mesons and generally hadrons and fermions can, yet they have mass and are incapable of reaching speed of light instead. Your explanation fails at black holes for example. Gravity there is so strong it stretches spacetime so far that light needs infinite time to travel from source of emission beyond event horizon and since our universe have measurable time frame since the formation of a black hole to any point of time in the future (in our understanding of spacetime at the current state) we can observe no light escapes black holes, which in oneself reinforces our current models. Einstein’s theory explains it perfectly yours doesn’t, sorry. Mathematically speed, time and space come together in this formula v=dt. It’s been tested and always predicted results correctly to a certain degree, you can check yourself if needed. Now if you were right it would mean everything’s speed is c, which is kinda weird on it’s on but harder to debunk in simple terms. So lets look at photons in your model t=0 for them always hence for photon v=0 always 😮 according to your model photons are at perpetual rest to everything in the universe. Incapable of travailing any distance at all. No matter from which point of space or time you look at a photon it should always be at rest relative to you! So sorry again but it’s better to be mistaken and find out then believe in a wrong thing, you on the right trek just didn’t reached the destination yet. Be patient and eventually everything will click into places. By the way interesting thinking, never heard something like this, made me think for a second, thank you for what! I can recommend to start from understanding that space and time are kinda sorta the same thing like matter and energy is. Not exactly but it’s a good enough start, what is established for now is they are intrinsically connected and inseparable hence the actual name spacetime. It’s just describes four dimensions of the universe which we can confirm at the moment. Good luck, hope I’ve been helpful and didn’t dissuaded you from digging deeper, it’s crazy out there, but fun I promise.

[@Mavrik9000]

@@Noblp As @huskypup3489 said C is constant for everything, which means that speed through space and rate of time trade-off in a reciprocal relationship when comparing two frames of reference, otherwise known as relativity. For an excellent visual representation and explanation watch the video called "We all move at the Speed of Light."

[@speedforce8970]

The speed of light being constant is a convention though, it could just be that the speed really is different in different directions.

[@FrostyBiters]

I DONT' BELIEVE I ever saw physics concepts presented so brilliantly. I was a chem student at Mcgill U when KZbin appeared, and I saw them all. I'm also an amateur artist and I appreciate the Art in your video so much. You're very CHARMING also and you are gonna get so much @$$%&* with your channel!!

[@deeeeeeps]

I've watched SOOOO many videos on this and finally someone explained it on my level. Thank you!

[@ColeTrain94]

9:40 is where you earned my sub. The amazing complexities of the universe are astounding and our grasp on them is so awe inspiring. I can feel in your voice the passion for this! Keep producing content! The world needs this!

[@peterrauth118]

Me too, just now

[@the-dave-house-project]

Read your comment before reaching 9:40... so, of course, I had to keep watching to see what inspired you. Pretty cool stuff. :)

[@alicekibbe]

I love how you are asking common senses questions (and answering them). Questions most of us can't get answered by physicists because they are incapable of stepping out of their wrote explanations. Great job.

[@danielshults5243]

I've only seen a few of your videos but they are easily some of the best on youtube. You make these things so intuitive!

[@anoobfrancis6613]

This is the best explanation I had in my life for time dilation. Finally a perfect use of mic on KZbin. Thank you

[@ARCWoodCraft]

Only someone who REALLY understands this kind of stuff can explain it this well, while being this excited about it! 🥳

[@FilthyGreen]

No other video on this topic has explained it as well as you have. I suddenly am able to comprehend time dilation and why it actually happens. You are an awesome teacher!

[@denizozkus8507]

I wasn't able to truly understand why did this happen, now I do. It goes without saying that you brilliantly put it, but what's more brilliant is that now I understand why I wasn't able understand it. It was because nobody outlined the importance of force carriers. Thank you it feels amazing.

[@PrabhuRPR]

I have watched videos on this topic for years now, and now at this video, I finally have a grasp of what’s happening. Thank you for making this!

[@irenerosenberg3609]

Took me a second to realize that what Mahesh calls "t dash" is what I would call "t prime". This was a great video! First time I have ever seen a good explanation of why not just time slows down, but so do actual physical phenomena when approaching the speed of light.

[@Mahesh_Shenoy]

Ah yes! I could have used the same lingo! Prime would have made it that much easier. Great feedback to be mindful about using shared vocab!

[@chunkymonky5364]

Absolutely adore your excitement and the love that you put into the content you produce. Never understood time dilation until now, and your joy from physics is contagious :) Please continue with such a high quality content! :D

[@sameyebam797]

after watching a bunch of your videos in preperation for this one, youve quentched one of my greatest pains. It has always perplexed me why you cant just continue to accelerate an object. but the thing is you can, Its all about how time is manipluated when we observe that object. Before i was filled with dread over this, now the world is just more bizare. Thank you

[@cubrman]

Insane clarity, thanks for that. It's amazing how accessible physics seems when described by a passionate articulate person, who really thought his topic through.

[@Aditya2364]

Who noticed "Don't be a jerk" 😂

[@Mahesh_Shenoy]

Yay! :D

[@DavidBairdSailing]

I don't know whether to feel smart because I finally understand special relativity, or stupid because I still don't understand the t-shirt.

[@utgfy]

​@@DavidBairdSailing It's the formula for how acceleration changes per second, also called the "jerk" formula.

[@unhpsychology3909]

I consume quite a bit of physics content on KZbin, and this video truly stands out as one of the best I’ve seen. I’ve never seen any of your videos before, but I am looking forward to seeing more!!!

[@tamilbabu5290]

This is so far the best ever explanation for time dilation in my life. Man, how did i not know you before all these days. How did you do this. Mind blowingly simplest explanation for such a topic.

[@RadCommieGamer]

What a BEAUTIFUL explanation! I got ever confused reading about it, but when you SHOW it graphically I got it! Thank you very, very much!

[@simonkembo]

Your ability to explain complex physics in a way dummies like me can understand is amazing. Excellent 👌

[@Mahesh_Shenoy]

I made a boo boo. The formula for the relativistic kinetic energy is WRONG at 0:10! But the concept is accurate and this doesn't affect the rest of the video. Sorry! Thanks Adrian for pointing that out.

[@Adrian-Carstea]

Keep up the good job.

[@sureshkumarkp8802]

Sheldon Cooper said the same thing when he gave Dr Stephen Hawking his paper with a math error I believe 😅 Context: The big Bang theory

[@Mahesh_Shenoy]

@@sureshkumarkp8802 Oh really? :D Haha.

[@sureshkumarkp8802]

@@Mahesh_Shenoy To quote him, "Oh my gosh golly! I made a boo boo... And I gave it to Stephen Hawking" and then he faints...

[@hadigmail]

I like your videos. How can we explain the biological aging difference in the twin paradox ?

[@PaulThatcher-iu5in]

This is without doubt the best explanation of something which (I thought) I already understood, intuitively: the quick Lorentz calculation was highly effective, and should be graspable by anyone with school level maths (so that's me included). I'm a linguist and English teacher, and I often explain to students that grammar may be "simple, but not easy", and that is true to the nth degree of Special Relativity - 42 years after leaving school, I still am awed by the power and far-reaching weirdness of SR, which is, after all, simple, but not easy. Thanks for this.

[@spacetaco048]

You know? They say the better someone is at teaching something to normal people, the smarter and more understanding they are on the subject. You are smarter than literal college professors.

[@RedHammerBodyShop]

I finally understand it completely. Thank you sir. My logic and ignorance has had me fighting this theory for years, and my brain finally "clicked" and I now fully understand. Thank you.

[@dexv1707]

Your home security is great 4:46 :vsauce starts playing

[@Amidaegon]

They say there is always an Indian guy on KZbin with a tutorial for any topic. Now an Indian guy made the best tutorial for relativity. I guess we can see "how to build a time machine" tutorial soon from some Indian guy. Amazing job.

[@adrian.joker1338]

This is the most intuitive explanation of this I've ever heard, love your videos bro!

[@stevenk8189]

It's great to see someone explaining what he loves with so much passion.

[@nevonachmani5879]

Hi mahesh, i’ve wrote you this message on instagram but you didn’t saw it. So ill put it here. Hello dear mahesh! Im writing you from Israel. Im a physics student thats waiting to start his last year in the university towards getting my first degree in physics. Im sure you’ve heard about the war thats going on in here, and because of that the university keep on delaying the start of the semester, so i didn’t learn physics in the past 6 months :(. Thankfully, i’ve came across your great youtube videos, and even though i’ve already learned most of the topics that you are talking about, i’m having a great time watching them. It really makes me feel better in those tough days. So I just wanted to thank you personally, and tell you to keep up with those amazing videos. Thank you So much❤️

[@Mahesh_Shenoy]

Wow, thanks a lot for sharing. Made my day. I am not active on Instagram, sorry :(

[@christianmohr6138]

One of the funniest and at the same time most understandable explanations I have ever seen. Thank you 👍

[@mikn999]

I love this video because his own reactions makes it seem like he's learning along with us and he's genuinely having fun doing it🔥

[@jeffwilson3818]

Reading the chapter about atoms in Richard Feynman's Six Easy Pieces led to an epiphany and an entirely new view of nature for me. It was the moment that atomic theory finally really "clicked" for me. I think I've just experienced that feeling again for SR after watching your explanation! By far the best, most intuitive explanation I've seen.

[@kfawell]

It has been so long since I read that book. I can say that I effectively remember nothing from the book. I have knowledge but by now at nearly 60 it is hard to keep track of where my knowledge came from . In short, would you mind offering a brief explanation of the epiphany?

[@jeffwilson3818]

@@kfawell It's been years since I read it and don't remember the specifics of what led to the epiphany, but I definitely remember the emotional feeling of that "aha!" moment. I think he was describing either evaporation or condensation, and how the normal interaction of atoms leads to these as emergent phenomena.

[@kfawell]

@@jeffwilson3818 thanks for telling me. I guess a good plan would be for me to read it again.

[@1conchitaloca]

After watching and reading so many explanations of time dilation, yours is by far the best, all others always left me with a "weird" feeling of just having to believe, but yours definitely didn't! Very well done! (I also had the question about the ship's perspective, but your second video solves that 🙂)

[@machineelf9459]

All my favorite teachers were just like you. Your enthusiasm and excitement is infectious and also leads to your presentation being very engaging.

[@Razuri_Zeev]

You are the only person I know who can perfectly explain relativity in simple way. Now I understand why. Thank you so much! There's no one I know who can explain this way. It's much better to understand.

[@ilin.andrii]

Man, you’re so good teacher! This content is definitely underrated. Wish you the best, man. Keep up a great work.

[@raffaelebernardo2801]

This was brilliant. Thank you. Mastering knowledge means being able to transfer it effectively within simple terms. Well done.

[@lande7510]

Hence the saying by Einstein, "If you can't explain it simply, you don't understand it". Thank you very much for this gem of a video Mahesh 🙏

[@rds1978]

Watching this 16:39 min video, I just spent about 15 min smiling nonstop. You made something I thought was so complex seem incredibly simple and beautiful. Thank you! I'm subscribing now and can't wait to learn more from your videos.

[@duckeydutch2088]

Best explanation I’ve ever seen. I actually understand this one 👍. Thanks!! What you could add is when you go faster and faster, de photons in the clock will describe flatter and flatter lines. At lightspeed they will go horizontal and don’t bounce anymore at all. Hence, time stands still.

[@AathielVaDaath]

I just got you channel in my suggestions yesterday and I've been binge watching you since then. You are a great science explainer and I love your willingness to look at the math- I appreciate the people who try to explain without the math, but it's such a crucial part... I look forward to your career taking off.

[@jimsmith9251]

Your explanation of time dilation is so easy to follow thank you so much. I'm going to be binge watching your videos as i have actually been able to follow you.

[@pm-px6pw]

Honestly, this is the best video on time dilation topic I've seen so far.

[@DJ_Force]

What I find interesting is how many different ways you can interpret Relativity and get the same outcome. You could also show that as velocity increases, length contracts along the direction of motion. As you accelerate, the apparent length shrinks so that the muon lives the same time, but the distance to Earth is shorter. Also, since length contractions is exponential, the faster you go, the more contracted the increase in distance the new velocity delivers. At c, the length is 0 so any increases in speed adds 0 more distance per time.

[@briandbeaudin9166]

Maybe I'm looking at it differently, but lengths (distances) obviously don't change, whereas the time changes can easily be measured. I see what you're getting at, the apparent distance is shorter because your speed is greater, so it takes less time to get there. That, however, is not what is actually happening. Time is the variable, not distance.

[@DJ_Force]

@@briandbeaudin9166 You say "apparent" distance, implying there is a universal distance all can agree upon. However, in Relativity, the only things all observers can agree upon are the speed of light and cause/effect. Distance and time are observer dependent.

[@johnmunton-G7SSE]

Agree with DJ_Force regarding distance & length being dependant on observer reference frame. Look-up "the ladder in the barn paradox" @@briandbeaudin9166

[@sattkrit_pathak]

the wavelength contract i guess ? red and blue shift. i might be wrong

[@Andrijko85]

This guy is my absolute favorite science communicator. Keep it up Mahesh! If we had more professors as excited as him, to teach their respective subjects, kids would definitely be doing better in school.

[@davidczajkowski5956]

Such an amazingly clear explanation and not one space-time diagram! Can’t wait to watch your other videos.

[@psfhellfire]

I got lots of classical textbook explanations throughout school, but this explanation,...mind blown...and subscribed

[@srinivasvellore447]

I am amazed how simplified explanations you come up with complex concepts. Hats off to you 👏 🙌 🙏

[@markchesnavsky3273]

Well, this video is worth more than all Instagram Reels and TikToks together that I have ever watched in my life.

[@CRU22]

I've watched other videos trying to explain time dilation and this is the first time it clicked for me.

[@Owen_loves_Butters]

Insanely intuitive. I just have one (admittedly technical) question. A function can have its rate of change approach zero as it approaches some limit value while still reaching it at a finite input. As an example, the slope of sin(x) approaches zero as the function approaches 1, but it still reaches 1 with a finite input (pi/2 units). How can we show that this isn't the case for the velocity function at a constant acceleration? (I'm ok with a non-intuitive answer).

[@YanivGorali]

I cant recall the number of videos on the subject and i never quite felt like i got it. Thanks to you and your ability to communicate so well, i finally got it. Keep up the great work!

[@user-ok9ih5zh2c]

Best teacher we'll ever have Cheers for mahesh

[@vasilikonstan]

Bro I have no idea what you are talking about, but I am thoroughly amused by your enthusiasm and charm❤️

[@chrislackey]

You've finally communicated this in a way that I understand! THANK YOU!

[@jasonmoquin]

You did a pretty good job at explaining this. FAR better than the professors did back in the day when I was a college student.

[@ponchogutz]

You are brilliant, not only because you understand what you explain, but because you got the amazing talent to explain it to us.

[@mikeshoults4155]

This is probably the clearest I have ever heard this explained. The way you explain it, an 8 year old could understand. Amazing.

[@stringpluka]

You really are brilliant. You keep covering questions I struggle to comprehend

[@robmoffett2700]

This is probably the 20th video I have watched about time dilation and none of the other videos explained it this well. I’ve never felt closer to an understanding of the concept. THANK YOU!! This video (and you) are a pleasure to watch. I do have some questions. If you are inside the ship and in a room with no windows as the ship is nearing the speed of light, what would you see when you looked toward the front of the ship? What would you see when you looked toward the back of the ship? How would photons of light behave within that room? It seems that the room toward the back of the ship would be very dark because fewer photons per second were reaching your eyes. Conversely, the front would seem much brighter because you would be receiving an overdose of photons per second.

[@mor911]

Bro you learned me some stuff today. Keep this up, you’re good at it. Subbed

[@tomb5372]

Wow, such great explanation and animation. Finally, I understand this concept and why it is the way it is! Thank you! Amazing video!

[@mseiya_kitgaede-vl5yj]

You deserve a Nobel Peace price for this explanation. I have been listening to proclaimed scientists on KZbin trying to explain this phenomenon and none comes close. You are a hero. Keep'em coming baby

[@audiodead7302]

This is an excellent video. I finally get it. I guess the underlying mystery now is 'why does light (or any force carrier) travel at a constant speed?'. No slower and no faster than C.

[@PADARM]

Maybe because life could not exist in a universe where infinite speed exists. Therefore we could only be born in a universe where there is no infinite speed.

[@audiodead7302]

@@PADARM Could life not exist in a universe where light travels at C+1kph?

[@PADARM]

@@audiodead7302 yes, maybe there is another universe where C=C+1kph. and there is another kind of living creatures. but no life can exist in a universe where C=infinity

[@ziomudru]

THANK YOU. a lifetime working as engineer with newtonian phisics, never had the chance and capacity to understand relativity. Now i feel like i have a very fair idea

[@LegateMalpais]

This kind of stuff needs to be on YT front page instead of all the other trash.

[@jouhannaudjeanfrancois891]

I've been trying to understand special/general relativity, speed of light etc... forever! (not the sharpest tool in the shed) you helped me make more progress than any science youtuber. Not there yet, but i now have a bit of hope. i will watch your videos over and over and get a grip of it. Thank you!

[@RussellSivalingam]

The knowledge, the passion, You sir are a born a brilliant teacher. After years, someone finally explained it to me in a way it's intuitive. for me you won't the internet today!

[@bobstanley8376]

This is by far the clearest explanation I’ve heard. It seems the actual “problem” is that c is unchanged in all perspectives. The fact that photons travel different distances at a constant speed is what really makes all this happen (or, not happen I guess)

[@forceinfinity]

Fascinating video and probably the most understandable explanation I've heard to explain ti-di and why you need infinite energy. Never occurred to me that the whole ti-di equation boiled down to a triangle

[@boowiebear]

I had always heard about the infinite energy and kind of understood but now that I know that it is required to make up for the time dilation it makes total sense. …and for relativity that is saying something. Bravo!

[@MultiPrince70]

I am not a Math person and I can easily get lost in it but you just made this video very easy to understand the math here. Thank you and yes keep infinitely doing what you do👍🏼👍🏼👍🏼

[@l337g0g0]

You read your comment section I agree, I finally now understand why speed of light slows time down, this was PERFECTLY articulated. Now I discovered something more for myself here, you just helped me understand how we could travel great distances in our universe. The speed of light takes light years to travel, and our universe is to big for us to go anywhere under that basic understanding of time we generally know. NOW,,, this explains how we could reach great distances traveling at near the speed of light, time slows down so much that it's close to 70times shorter when traveling at near that speed. So traveling 100 light years would only take 7 years. and as you chart shows that you can probably make that number lager the closer you are traveling to the speed of light. The 99.99999999% speed of light slows time down so much that people on a ship traveling at that speed could travel the universe, this explains why light travels hundred's of billions of light years and we can see 100 billion light years away. Light traveling has no time...

[@Laidtorest69]

I’ve never seen anyone explain it this way and now it completely makes sense thanks