One of the most gifted physics educators of our time!! Keep up the outstanding work Dr. Lincoln!

I finally understood the barn paradox. Math and animations were easy to understand. Thanks for another great video

I've been trying to understand special relativity all my life (I'm 65). Now, in just a dozen videos, Dr. Don has finally gotten it through my thick head. Thank you! TRIPLE the Fermilab budget, please.

I love this guy, because he is not afraid to give the derivations and you know you can trust every word he says.

This channel has a strong PBS Space Time vibe and I love it, great video.

Mr Lincoln, please keep these videos coming!!!!!!!!

@iambiggus

6 жыл бұрын

constellationpegasus Dr. 😉👍

@paulmichaelson7203

6 жыл бұрын

Please, Doctor Lincoln! (He deserves it.)

@constpegasus

6 жыл бұрын

ScienceNinjaDude Then Zoltan it is.

Mind blown yet again. Thank you Dr. Lincoln for another great video explanation!!!!

You like a real serious professor one would expect in a university talking about dry topics, but your t-shirts and the prefessional nature of your presentation reveal someone with a superior sense of humor who mastered the true art of subtly delivering the punchlines. Keep those videos comming!

Great explanation! The basic math really helps a lot in understanding the relations there. Just please keep up making those awesome physics videos, I really love those.

Way cool, and the math isn't that tough. And you're definitely NOT wasting our time!

@Penguinz13989

5 жыл бұрын

it was a rhetorical question buddy

@tetsujin_144

4 жыл бұрын

I don't know, he's maybe wasting our time a little bit when he explains how to measure a stick a good two or three times before getting to the relativistic version.

@-danR

4 жыл бұрын

He's not wasting our time, but some of this presentation is _false_ . 8:56 What you would actually _see_ of the basketball is a spherical ball, albeit with the seams strangely reconfigured. This is Penrose-Terrell rotation, and he almost certainly would know of it, relativistic colliding nuclear particles notwithstanding. math.ucr.edu/home/baez/physics/Relativity/SR/penrose.html

@talhaehsan8096

3 жыл бұрын

@Kisa Vorobianinov if this was just optical effect you wouldn't be fittinv 20 meter stick in 10 metre.

This is the third video I see about this topic and this one is the most comprehensive! Thank you! I hope you take care of your gym time.

Love the barn example. Also, saying that these effects are measured during {X} experiment is really helpful. These series of videos are great!

I misunderstood length contraction until your caveat about the time of measurement in the primed frame. That, and the fact that if you take away the stick, you still have coordinates doing their thing, was super illuminating. Thank you for such a crispy clear explanation! I’m learning how current densities transform from one inertial frame to another and this was the missing piece. Many thanks! 😁☺️🙌🏽🎊

@zhinkunakur4751

Жыл бұрын

hey i am also confused about that , can you help me ? As of now I am confused why current densities remain constant in primed frame but not in the moving elctron's frame , since in the rest/prime frame the current densities should also be changed

@frankdimeglio8216

Жыл бұрын

@@zhinkunakur4751 In understanding SPACE, what is gravity, TIME, AND time dilation (ON BALANCE), it is important is it to understand what is a BALANCED displacement of what is SPACE. ELECTROMAGNETISM/energy is gravity ON/IN BALANCE. Consider what is E=MC2. TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE. Consider TIME AND time dilation ON BALANCE. (c squared CLEARLY represents a dimension of SPACE ON BALANCE.) Indeed, the stars are POINTS in the night sky ON BALANCE. The rotation of WHAT IS THE MOON matches the revolution. Consider what is THE EYE, AND notice what is the TRANSLUCENT AND BLUE sky ON BALANCE. NOW, consider what is the BALANCED MIDDLE DISTANCE in/of SPACE. CLEARLY, BALANCED inertia/INERTIAL RESISTANCE is fundamental (ON BALANCE). “Mass"/ENERGY IS GRAVITY. ON BALANCE, consider what is the orange (AND setting) Sun. “Mass"/ENERGY involves BALANCED inertia/INERTIAL RESISTANCE consistent WITH/as what is BALANCED electromagnetic/gravitational force/ENERGY, AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE); AS gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE (ON BALANCE) consistent WITH E=MC2, F=ma, TIME, AND time dilation ON BALANCE. This CLEARLY AND NECESSARILY represents, DESCRIBES, AND INVOLVES what is possible/potential AND actual ON/IN BALANCE, AS ELECTROMAGNETISM/energy is CLEARLY (AND NECESSARILY) proven to be gravity (ON/IN BALANCE). Notice what is the fully illuminated (AND setting/WHITE) MOON ON BALANCE. Great. TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE. Indeed, inertia/INERTIAL RESISTANCE is proportional to (or BALANCED with/AS) GRAVITATIONAL force/ENERGY; AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE). This CLEARLY explains what is E=MC2 AND F=ma ON BALANCE, AS TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE !! (Consider TIME AND time dilation ON BALANCE.) Great. Indeed, consider WHAT IS THE EARTH/ground ON BALANCE. I have mathematically proven why the rotation of WHAT IS THE MOON matches the revolution, AS ELECTROMAGNETISM/energy is CLEARLY (AND NECESSARILY) proven to be gravity (ON/IN BALANCE). Consider TIME AND time dilation ON BALANCE, AS the stars AND PLANETS are POINTS in the night sky ON BALANCE; AS c squared CLEARLY represents a dimension of SPACE ON BALANCE. (Consider what is THE EYE ON BALANCE.) I have mathematically proven what is the fourth dimension, AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE) !!! I have explained why what are OBJECTS may fall at the SAME RATE. By Frank Martin DiMeglio

@misterlau5246

4 ай бұрын

I think you are not considering the observer who Co-moves with the electron can't perceive that. The phenomenon in particle lab and acceleration of electrons is.. 🤔 Well. You get wavefronts, and the measurements at the first one, has more electric charge density, similar to the ambulance which has Doppler effect. Now, this is an effect that happens for real. It's odd of course. And the reference frames do work. I repeat. These phenomena occur, weird but real

It was an amazing,I hope it gets more views,it made it really clear

Dr Lincoln, you have a geology based doppelganger in Nick Zentner. You make incredibly complex subjects very accessible to laymen. AND, you have a way of communicating that is very enjoyable to watch and hear. You and Mr Zenter should be required subjects for people studying to become teachers.

You sir, you are that such a person! We study time dilation and length contraction in my modern physics course. I find this concept fascinating. You have explained it very well! Thank you.

Omfg I understood everything and I'm an idiot! Dropped out of high school and lost memory of most my childhood and schooling This guy is a science/maths god! I whole heartedly believe in the adage "The only good is knowledge and the only evil is ignorance" -Socrates. You sir are a champion of good! Thank you so much! Thanks to you I actually think I could do physics! Me of all people! Your so great at teaching! ❤

@macbewmagoo8616

4 жыл бұрын

💟

I like how you put the equations in there while you're talking about it even if I don't understand the math I still get the principal excellent videos

@Ragnarok540

5 жыл бұрын

All the math in this video is high school level, is just algebra.

@dreamdiction

4 жыл бұрын

hahahaha he's a con man and he got you.

@cosmoscomputers4920

4 жыл бұрын

Mate, why are you studying special relativity if you don't know high school Math?

@dinghanxue704

3 жыл бұрын

@@cosmoscomputers4920 I think maybe he means that he does not know where the equations are coming from. Solving these two equations is easy... but the problem is.... they are hard to imagine.

@frankdimeglio8216

2 жыл бұрын

@@dreamdiction TIME DILATION IS FULLY EXPLAINED, AS THE ULTIMATE MATHEMATICAL UNIFICATION OF PHYSICS/PHYSICAL EXPERIENCE IS CLEARLY PROVEN: A PHOTON may be placed at the center of what is THE SUN (as A POINT, of course), AS the reduction of SPACE is offset by (or BALANCED with) the speed of light; AS ELECTROMAGNETISM/ENERGY IS GRAVITY; AS E=MC2 IS F=MA. Gravity IS ELECTROMAGNETISM/energy. (The stars AND PLANETS are POINTS in the night sky.) Time DILATION ULTIMATELY proves ON BALANCE that electromagnetism/ENERGY IS GRAVITY, as C4 is a POINT that is ELECTROMAGNETIC/GRAVITATIONAL (ON BALANCE) as SPACE; AS E=mc2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Time DILATION proves that electromagnetism/ENERGY IS GRAVITY, AS E=mc2 is DIRECTLY and fundamentally derived from F=ma. E=mc2 IS F=ma. A planet AND a star thus constitute what is A POINT in the night sky. It ALL CLEARLY makes perfect sense. Gravity IS ELECTROMAGNETISM/ENERGY. ACCORDINGLY, I have ALSO fully explained the MATHEMATICAL UNIFICATION of Einstein's equations and Maxwell's equations (GIVEN THE ADDITION OF A FOURTH SPATIAL DIMENSION); AS E=mc2 IS F=ma. The Sun AND the Earth are F=ma AND E=mc2. Great. SO, ultimately and truly, TIME is NECESSARILY possible/potential AND actual IN BALANCE; AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. AGAIN, time DILATION ULTIMATELY proves ON BALANCE that E=MC2 is F=ma; AS ELECTROMAGNETISM/energy is gravity. Great. Indeed, this NECESSARILY represents, INVOLVES, AND DESCRIBES what is possible/potential AND actual IN BALANCE. (E=mc2 IS F=ma.) Therefore, INSTANTANEITY is thus FUNDAMENTAL to what is the FULL and proper UNDERSTANDING of physics/physical experience; AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. SO, GRAVITATIONAL force/ENERGY IS proportional to (or BALANCED with/as) inertia/INERTIAL RESISTANCE; AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE, AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/energy is gravity. Accordingly, the rotation of WHAT IS THE MOON matches it's revolution. MOREOVER, a given PLANET (including WHAT IS THE EARTH) sweeps out equal areas in equal times consistent WITH/AS E=MC2, F=MA, AND what is perpetual motion; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. "Mass"/ENERGY IS GRAVITY. ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity AND ELECTROMAGNETISM/energy are linked AND BALANCED opposites, AS E=MC2 IS F=MA; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. GREAT !!! It ALL CLEARLY makes perfect sense. BALANCE and completeness go hand in hand. Very importantly, outer "space" involves full inertia; AND it is fully invisible AND black. E=mc2 IS F=ma. "Mass"/ENERGY involves BALANCED inertia/INERTIAL RESISTANCE consistent with/as what is BALANCED ELECTROMAGNETIC/gravitational force/ENERGY, AS E=mc2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. (Energy has/involves GRAVITY, AND ENERGY has/involves inertia/INERTIAL RESISTANCE.) E=MC2 IS F=ma. Objects fall at the SAME RATE (neglecting air resistance, of course), AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity IS ELECTROMAGNETISM/energy. E=MC2 IS F=ma. It ALL CLEARLY makes perfect sense. Magnificent !!! By Frank DiMeglio

One of the oldest but underrated channel , tho it has quality content 😟

Another awesome vid. Thanks, Dr Lincoln!

Professor Don I like your every videos it helps me a lot to understand physics again in an interesting manner. Thank you Sir. Sir kindly make a video on why scientists are facing difficulties in achieving superconductivity at room temperature.

Answer: This happens when a man enters into a cold pool of water. Question: What is Length Contraction?

@kseriousr

4 жыл бұрын

I understood that reference!

@SureshKumar-uz8ld

4 жыл бұрын

🤣🤣🤣🤣🤣🤣🤣🤣

@SureshKumar-uz8ld

4 жыл бұрын

Primed and unprimed both in the cold pool have length contraction

@1.4142

4 жыл бұрын

@@kseriousr I understood that reference

@sergiob8501

11 ай бұрын

typical comment coming from the back rank of basically any classes all around the world!😅

Your explanation is so cool! Thanks! Many textbooks contain mistakes and confusion! Thanks for this wonderful video!

Glad we have you, doc!

So..... the earth could be flat at high speed..... mmmhhhhhmmmmmmmmm.........

@ZeedijkMike

6 жыл бұрын

Oh - Don't you start with that. (-: (But it does kind of make sense though)

@magichands135

6 жыл бұрын

Gaspar Albertengo Not for the people ON the earth, for the observer. It's like saying a siren sounds distorted for the people in the car.

@thewormholetv7228

5 жыл бұрын

@@satunnainenkatselija4478 r u indian or Russia

@DoctorRocker66

5 жыл бұрын

We are not outside that frame of reference though.

@RonJohn63

5 жыл бұрын

@@DoctorRocker66 the Reptilians from Nibiru think the Earth is flat... :)

i bet no other video on youtube descibes relativity like this series here.congradulations.

Sir, I really love your videos. Thank you so much for sharing and please continue.

The way you shown things makes the math raiser. You get it to say what is needed for your explanation.

“Physics is Everything”

@sufsanin1917

3 жыл бұрын

Lol it feels like Trump is screaming this from his balcony. Instead of the world "everything" he prefers the world sh*t.

@stephenfiore9960

3 жыл бұрын

...Don’t know about that, but Solomon said “Vanity of vanities, saith the Preacher, vanity of vanities; all is vanity.” Ecclesiastes 1:2 - www.biblegateway.com/passage?search=Ecclesiastes%201:2&version=KJV

This was the best explanation of this I have seen using pre high school math! I wish there was something similar available way back when I was at University. When we got in to tensor algebra of relativity we had probably still a rather foggy picture of what was going on as explained here. Which is evidently still true since people still promote non existent paradoxes. Many courses on advanced subjects would benefit from starting with a simple explanation like this. Quite the opposite I remember the professor talk about achieving mathematical maturity first and then getting into applications later. I think this is the wrong approach, at least for applied math and physics. In my view math is a simplified language to describe reality, so it helps to have an idea of the what You try to describe in the physical world.It is like skimming a book helps to get an overview before getting into the details.

Thank you Don and team! You are awesome!

And thank you for taking the time to explain.

As always, Doc, spot on! I am re-teaching myself relativity from my university physics days, and your videos are always a great addition to my studies!

2:18 Actually, I tried to do that a few hours ago..... But somewhat, my derivation was: d’=t’•√(c²-v²)

@nikhilsomvanshi9960

3 жыл бұрын

Your derivation is correct!

Thank u Dr Don I certainly enjoy your demonstration ofknowledge

love the enthusiasm and really well explained!

What would happen if you put a length contracted stick into a barn, closed the doors, then it hits the door and decelerates (assume very strong door) The stick is longer than the barn, yet it is inside the barn and no longer subject to length contraction?

@ANGRYpooCHUCKER

5 жыл бұрын

The observer who sees the stick moving but the barn stationary, sees that the stick has shrunk and can fit in the barn. Then, the stick hits the right door. Assuming the observer could see inside the barn, of course (maybe there is a window or a larger door facing the observer that is open), then they would be amazed as they watched the stick suddenly grow rapidly and kick the other door back open. That's the primed observer. The unprimed observer would see that the barn is shrunk initially and moving, but that the stick was stationary and longer. But remember, events that are simultaneous for one observer are not simultaneous for another. So the unprimed observer would see the stick enter the barn, and then hit the right door. Immediately the unprimed observer would see that the stick is starting to shrink because it is now moving relative to the unprimed observer, since it is being accelerated to the left (hits the door and decelerates). The unprimed observer would then see the back door try to close but it would hit the stick and be pushed back. So both observers would agree that the back (left) door tried to close but hit the trailing end of the stick before it could close all the way, resulting in it being kicked back open.

@jeromedavies2408

4 жыл бұрын

Well, a stick hitting a barn door at 85% of the speed of light would be pretty spectacular as teh energy released would vaporise everything in a considerable radius.

01:19 I'm a musician, Don... I have to trust you! 🤯

I have to give to you. If I don't fully get the explanation of a physical phenomenon, I always turn to Fermilab to clear it out. Many thanks!

I'm so glad I found out about this channel. One should never judge a channel by its number of subscribers, or should do it the opposite way : the more subscribers, the more likely the content is for everyday people 😂

This might explain something I have observed on Grindr...

Great video, great explanation. Relativity is the second most weird thing in the universe. Guess what is the first.

@marechuber

6 жыл бұрын

Boaz Augusto Matos The solution to the Teleportation noncloning theorem ,which for now, has been hidden from human knowledge by our Creator, thats truly brilliant thinking !

@BoazAugustoMatos

6 жыл бұрын

ScienceNinjaDude it was meant to be Quantum Mechanics.... but I forgot women...

@vitakyo982

6 жыл бұрын

English food ...

@markstanbrook5578

6 жыл бұрын

Belly button fluff?

@honved1

5 жыл бұрын

My mother

Well done. A good follow-on would be exploring how this is related to what happens to coordinate and proper distance in Schwarzschild geometry.

This sounds like the basis of most arguments, one person sees/perceives one thing that the other doesn't, all the while the truth is actually perpendicular to them. Lol. Thank you, Dr. Lincoln, for your insight as always, these are a pleasure to watch.

So wierd, it says 100+ comments but I can only see about 10 and no replies to comments. My internet speed must be approaching the speed of light and I am experiencing information contraction...

@derdagian1

4 жыл бұрын

I can give you a heads up, if you’re lost. Basically, I own the Universe, now.

so whats the physics of length contraction? proving it mathematically isn't saying why space time contracts. I get it mathematically ,but I still fail to see how space time contracts when a mass is moving at high speeds. how does space time contract? is it because the mass going at such speeds warps space time? if so does that mean it has a greater gravitational pull as there is more energy from the object.

@okuno54

6 жыл бұрын

Spacetime doesn't contract at all in these examples. It's just that different observers might have different perspectives on spacetime based on their relative speeds. In fact, near the end of the video, it's mentioned that you don't need a stick to derive the same effect, so mass is completely not involved. Remember: special relativity shares a lot in common with the idea that the world looks upside down if you stand on your head; it's just that instead of normal rotation, you need the math for hyperbolic rotations, which is pretty unintuitive. As for the why question, rephrased to "why do observer's perspectives on spacetime change with speed": well, that's just the way it looks if you look closely enough. I suppose it's a fruitful philosophical or religious question, but not a particularly scientific one.

@albirtarsha5370

6 жыл бұрын

I believe that all this is intimately connected with the relativity of simultaneity. I think that having a firm grasp of that helps to understand spacetime.

@MisakaMikotoDesu

6 жыл бұрын

The stick is made of particles. When a force acts on one end of the stick to begin moving it, the force can only be transmitted through each particle, at most, at the speed of light. If the stick is moving near the speed of light, the particles can still only interact with each other at the speed of light. This means it still takes time for one end to affect the other. Since the stick is going nearly the same speed as the particles can transmit the force, this means the particles will need more time to "catch up" with the particles ahead of them. Due to the fact they're moving, this also means the transmission of the force will need to happen over a greater distance in space, compared to the stationary stick. This is why time slows down as you move faster through space. It's also why you appear to turn into spaghetti to people who aren't moving; the particles literally need to cover more space to transmit the fact you're moving so fast. You can really think of time as being how fast your particles can interact with each other. That's why time isn't the same for everyone.

@IllidanS4

6 жыл бұрын

It all boils down to the fact that since photons cannot slow down, the universe must compensate for that.

@harlesbalanta2299

6 жыл бұрын

I can't even see the replies

Great video professor Don. I had to rewind it like 10 times but it was worth the effort. I still need to watch it a couple times. But now I understand for the first time the math it's all about.

Thank you for such a nice explanation.I always had a nagging feeling about "bookish" explanation of length contraction and knew that, there is a better explanation.Thanks for making it clear.

the term "simultaneous" should not be used to explain relativity

5 жыл бұрын

Isn't it that every observer can define and use the concept of simultaneously for events, but it may not be simultaneously for another observer?

@jacobm5167

4 жыл бұрын

Why? It's a relative notion.

Now when I see pancake I always ask myself - is it really flat or it is just moving on speed of light relative to me?

@BillAnt

5 жыл бұрын

As they say, everything is relative from the perspective of the observer. A perfect example is when you're standing on Earth you feel no motion at all while an observer from the space station can actually see the movement. Then of course things start getting weird at near the speed of light which is what this video is trying to tackle (among other things).

Nice explanation ! To understand, everyone must start somewhere.

I love the way you teach. Thank you

When an object travels at a high speed,does the plank length contract ?

@fool5541

5 жыл бұрын

Hamani Maka no

@hotelmike7722

5 жыл бұрын

@@fool5541 why?

@fool5541

5 жыл бұрын

Hamani Maka because universal constants don t change no matter what happens, the object’s length contracts, but it will never be shorter than Planck length.

@michalchik

5 жыл бұрын

I really don't know but I would think it would have to otherwise you would start changing the physics observed between different inertial frames of reference. I think that Planck length is inextricably tie two things like electromagnetic force and gravitational force

@fritt_wastaken

5 жыл бұрын

@@hotelmike7722 Yes. You'd basically have "different" plank lengths for each observer. But it doesn't change physics, objects themselves are different when they're moving, and that cancels the change.

A sphere will never flattened to an ellipsoid.... Terrell Penrose effect... the misconception of length contraction must be removed from the vido.

@k6l2t

5 жыл бұрын

For the lazy~ Link: en.wikipedia.org/wiki/Terrell_rotation Relevant quote: "A previously popular description of special relativity's predictions, in which an observer sees a passing object to be contracted (for instance, from a sphere to a flattened ellipsoid), was wrong."

@henrykeplerIII

2 жыл бұрын

The Terrel Penrose effect was revisited by Robert J. Deissler in the 2005 paper "The appearance, apparent speed, and removal of optical effects for relativistically moving objects"

Everything just clicked in the last minute of this video. What an amazing explanation!

I like that Lincoln often sticks to the appropriate equation in his explanations, which is helpful in the education sector. But, for seasoned pros, we know that length is actually defined by the distance a beam of light travels. So, you have had enough of education already, you don't even need the equations any more. You know when someone is moving, the time he/she spent on moving while measuring the stick needs to be added to the equation of calculating the stick's length. Then, of course, the length of the stick will vary depending on the speed he/she travels.

And this person is Matt from PBS Space Time :D

A muon approching earth at almost speed of light, sees a flat earth. So , is earth flat ? According to the muon it is. Is length contraction a real effect, or a perspective effect? If 2 persons move away from each other, they see the other getting smaller and smaller. Nobody is getting realy smaller.

@mariodiaz3976

6 жыл бұрын

Yves Bulté a muon would decay faster than light is able to travel from the Earth to it's positon if It wants to see the whole Earth

@mariodiaz3976

6 жыл бұрын

Yves Bulté a muon can't even travel at the speed of light because it has masa

@albirtarsha5370

6 жыл бұрын

Yves Bulté Yes, someone IS really getting contracted. Who is getting contracted is relative. Each observer is correct in his own inertial frame of reference.

@awfuldynne

6 жыл бұрын

High-speed particles with short half-lives travel farther than they would be able to in their short lifetimes without relativistic effects. From an outside perspective, time is running slow for the particle. From the particle's perspective, the universe is "flattened", so the travel distance is shorter.

@AlipashaSadri

6 жыл бұрын

"From a certain point of view" yes, the Earth is flat. :) Vsauce has a video about it.

Great series, thank you.

Thank you for this explanation!

I wish too there would be such a person. But not found yet... jk

Next weak: "Length contraction: the imaginary explanation"

for me it is the best of Dr Lincoln so far (and I've seen them all) but what strikes me is the supreme role of algebra in reaching the conclusion and how Dr Lincoln surrendered his problem to it. you might think this is obvious and simple but i still see algebra as being on top of even Relativity. sheer magic.

I simply used the thought experiment from your Lorentz factor derivation. The equations in my derivation were: L₀=c•∆t L=∆t•√(c²-v²) So: ∆t=L₀/c And now if we do some simple algebra, we get: L=L₀•√[1-(v/c)²] L=L₀/γ

Took me a few times of watching the video to understand, but I got it eventually! Great video!

Dr Lincoln is back...with more Relativity matter! :) I have to say, I got lost daydreaming at the equations. I should have looked at them with the Length contraction framework in mind. Well, time to press replay...

Amazing video again! Thank you

Great video Dr Don. What about simple distance compression (i.e. perspective length compression ?) Does the perspective ratio change for off Earth satellite observations ?? Uncompressed for the immediate environment of the observer , observationally proportionately compressed for anything at a distance (i.e. unique to the observer) Time/Velocity moves slower observationally for the Observed yet both observed and observer are experiencing time at the same rate ? So no velocity required for x,y,z length compression only distance ? *;-))

Great video! First video on length contraction I actually understood

Good clear video as always.

Well done. Very clear.

Great video. Superb explanation!

thank you so much for making this video!!!!!

Great job, applications in speed of light and fiber optics as well-which is my business!

Thank you for the great video

The math is easy enough that any high schooler who does their homework could keep up with this video. Please keep doing videos with math in it like this. People need to understand that math allows us to understand things even if we can't directly observe them.

You have never wasted my time! I was learning!🤓😁

I always think of it this way. Distance per unit time = speed. If we both agree that light travels at the same speed, then we must disagree on how long something took or how much distance was covered in order to get the same answer for the speed of light. The very definition of speed connects time and space and Relativity show us how.

Man, i love You Fermilab Guys

An excellent channel, keep the physics coming

Good stuff. Keep 'em comin'.

Nicely presented! 😊

I watched this video last night and I'm reviewing it again this morning. I've been slowly trying to wrap my head around these concepts for a while now and truthfully many explanations, such as the rubber sheet explaining gravity, don't really help much because they oversimplify. I especially like Dr. Lincoln's explanations because they are easy to follow yet don't approach things at the "rubber sheet" level. Pondering length contraction and some other aspects of GR and other such subjects has raised questions in my mind about what is the underlying physical reality. The video begins with Dr. Lincoln saying that we "see" a length contraction. That's the observation. Understood. But supposing that there were a way to physically measure another object as I pass it at relativistic speeds would that observation be the same as the observation from photons. Is space actually contracting or does it just appear that way?

Great explanation, Thanks! Imagine the accretion disk of a black hole. Incoming matter moving faster and faster, getting flatter and flatter, packing immeasurable density into the disk.

Thank you Sir, you are simply great , visionary too deep and clear so well in the labyrinth of physics. Regards BKJ

Could you explain to me why a wire with current on it is still neutral charged for a not moving charge next to it even though that charge sees the electrons including the gabs between them moving and this contracting?

Awesome video!!

Great explanation. I have a slight issue with saying this is what you would "see" rather than this is what you would "measure". In fact a moving sphere does not look flattened. When we talk about seeing we are talking about the light rays entering the eye. Roger Penrose showed in the1950s that a sphere does not look contracted (See the wikipedia page for the Terrel rotation - also from the 1950s). What happens is that the celestial sphere centred at the observer is transformed by a Möbius map (when considered as the Riemann sphere using stereographic projection) (Note that the proper orthochronous Lorentz transformations are isomorphic to the Möbius group). Möbius maps preserve circles-and-straight-lines and stereographic projection also preserves circles, so the sphere does not seem distorted.

@bobjones7908

2 ай бұрын

You are right, I called it Lorentz rotation, and it is obvious. As the ball passes, you still see a round ball, but it is rotated so you see its backside. consider th e light entering your eyes as forming what you see, not what is.

Could there be an objective understanding of this with space and time being emergent properties relative to the energy and momentum of our actions?

That was GREAT! Thanks man!

great teatching easy to understand

I do like how this all makes sense in a nerdy kind of way, and if I study it enough I may end up thinking I understand it. At least I will be confident enough so Dunning Kruger will get the best of me ;)

Great explanation. Makes me wonder how this relates to the wavelengths of light itself.

Very cool way to teach sir👍🏼👍🏼

Dr Lincoln, please make video about general relativity. I think you are good at explaining complicated things

Thank you Dr!

Make videos on as high level of physics as you can, please. I love it so much. Has string theory failed us, even with ADS/QCD? Does the weak force break CPT? How can cold Fermions turn into Bosons? What the hell do Vector bosons do? Always MORE!!!

Very interesting video. I have one question: suppose that I move towards Alpha Centauri at such a high speed that the distance dilates to 7 light minutes. Then I (as the primed observer) will see that star at a distance of 8 light minutes. Does that mean that I will also feel its heat? After all, our Sun is at that distance from Earth and we can feel its heat.

My question regards the path of travel from the frame of reference of the moving object, or one of a comoving observer. Does the observer see the path ahead contract? If so is it an illusory effect caused by time dialation, and even if so, wouldnt this still mean that assuming it's possible, a traveler could reach almost anywhere in the observable universe in a couple of years from their perspective with a 1g constant acceleration capable ship?

frame jumping requires acceleration, but the magnitude of the time-shift depends on the delta velocity and position where the change in velocity happened.